GEAR AND EQUIPMENT
SHIP'S GEAR AND RIGGING PROCEDURES
3-1. INTRODUCTION. This chapter covers various types of ship's gear and discusses its safe operation. Terminal operations personnel must know the proper terms and concepts in order to understand this chapter.
3-2. CHAINS, HOOKS, AND SHACKLES. Information on chains, hooks, and shackles is as follows:
- Make sure pins are straight.
- Make sure that screw pins are screwed in all the way.
- Make sure that nuts on safety pins are snug against the eye of the shackle and cotter pins are inserted before the shackle is used.
- Make sure widths between the eyes are not greater than they were originally. Excessive widths indicate that the shackle had been strained and should not be used.
- Make sure, when shackles are placed under strain, the bearing surface of the sling or fitting being used covers the entire bearing surface of the shackle pin. If the size of the sling or the size of design of the fitting makes this impossible, then another size shackle should be used.
a. Chains. Chains are used in cargo-handling operations for slinging loads and lashing cargo and as part of the ship's rigging.
(1) Chains are made up of a series of metal links formed into oval shapes and connected through each other. The chain size refers to the diameter of the metal link. Chains will stretch due to overloading and the individual links will bend slightly. Bent links are a warning that the chain has been overload. Overloading could cause the chain to fail. If a chain is equipped with the proper book, the hook should start to fail first, indicating that the chain is overloaded.
(2) Chains are much more resistant to abrasion and corrosion than wire rope; therefore, chains are used where this type of deterioration is a problem. For example, chains are used for anchor gear in marine work where the chains must withstand the corrosive effects of seawater. They are also used as slings to lift heavy objects with sharp edges which would cut wire. A number of grades and types of chains are available.
b. Hooks. There are various types of hooks. The types are as follows:
(1) Cargo hooks. Chains, fiber rope, or wire rope can be tied directly to the load. However, for speed and convenience it is much better to fasten a hook to the lifting line. Cargo hooks are shackled to the cargo runners for lifting and lowering drafts of cargo. The hooks most frequently used in cargo-handling operations are the new york cargo hook, the liverpool hook, and the seattle hook. Figure 3-1 shows these three types of hooks.
(a) The new york cargo hook is a dropforged steel, natural-colored hook, fitted with a jaw-and-eye swivel.
(b) The liverpool hook is a dropforged, natural-colored steel hook, fitted with a double-eye swivel. This hook is included in the general-hatch set and has a safe working load of 11, 200 pounds.
(c) The seattle cargo hook is a dropforged steel, natural-colored hook, fitted with one jaw-and-eye swivel, two double-eye swivels, and a ring. It may also have a double-eye swivel in lieu of the jaw-and-eye swivel. This hook is included in the general-hatch cargo set and has a safe working load of 11,200 pounds.
(2) Sling hooks. Hooks can be used in conjunction with slings in many different ways. They can be shackled, moused or spliced into an eye, placed on the sling before the eyes have been spliced to permit the hook to slide, or used with chain slings. Four general types of hooks available for slings are the slip hook, grab hook, box hook, and the chime or drum hook. (See Figure 3-2).
(a) Slip hooks are made so that the inside curve of the hook is an arc of a circle. Cargo handlers may use slip hooks with wire rope, chains, and fiber rope. Chain links can slip through a slip hook so the loop formed in the chain will tighten under a load.
(b) Grab hooks have an inside curve which is nearly U-shaped so the hook will slip over a link of chain edgeways but will not permit the next link to slip through. Grab hooks have a more limited range of use than slip hooks. They are used when the loop formed with the hook is not intended to close up around the load.
(c) Box hooks are heavy steel hooks with a studded steel plate on one end and an opening on the other end through which a sling can pass. Cargo handlers should use box hooks in pairs by attaching them to the sling in such a way that the studded plates are facing each other. When the hooks are positioned on a case or a box and the ends of the sling are placed on the cargo hook, the sling draws the studded plates tightly against the case as it is lifted. Box hooks are designed to lift heavy cases high enough to permit easy slinging. Cargo handlers should never use box hooks on fragile cases.
(d) Chime or drum hooks are forged steel flat hooks with an opening in one end through which a sling may pass. The hooks are used in pairs and placed on the sling so that they face each other. The hook end is designed so that it fits the chimes of barrels or drums. Cargo handlers usually attach the hooks to endless chain slings. Several slings are then shackled into a spreader to form a bridle which will accommodate several drums at one time.
c. Shackles. Anchor, antitoppling, and chain shackles are the principal types of shackles. Round, screw, and safety pins are the principal types of shackles pin (Figure 3-3). When using shackles, personnel should-
Figure 3-3. Shackles and safety pins
d. Safety and Inspection. There are safety and inspection procedures for chains and hooks. These procedures are as follows:
(1) Responsible personnel should inspect chains, including the hooks, at least once a month. Chains that are used for heavy and continuous loading require more frequent inspections. Personnel must pay particular attention to the small radius fillets at the neck of hooks for any deviation from the original inner arc. Each link and hook must be examined for small dents, cracks, sharp nicks or cuts, worn surfaces, and distortions. Those that show any of these weaknesses must be replaced.
(2) When hoisting heavy metal objects using chains for slings, insert padding around the sharp corners of the load to protect the chain links from being cut. The padding may be either planks or heavy fabric. Do not let chains twist or kink when under strain or connect them with bolts or wire; such connections weaken the chain and limit its safe working capacity. Cut worn or damaged links from the chain and replace them with a cold shut link. The cold shut link must be closed and welded to equal the strength of the other links. Small chain links can be cut with a bolt cutter. Large chain links must be cut with a hacksaw or oxyacetylene torch. Inspect chains frequently. Apply a light coat of lubricant to prevent rusting and store chains in a dry and well-ventilated place.
(3) Hooks usually fail by straightening. Any deviation from the original inner arc indicated that the hook has been overloaded. Since evidence of overloading the hook is easily detected, it is customary to use a hook weaker than the chain to which it is attached. With this system, distortion of the hook will occur before the chain is overloaded. Severely distorted, cracked, or badly worn hooks are dangerous and should be discarded.
(4) Sling hooks should always be "moused" as a safety measure to prevent slings or ropes from slipping off. Mousing, the binding of hemp or wire across the opening of a hook to prevent it clearing itself, also helps prevent straightening of the hook but does not strengthen it materially. To mouse a hook (Figure 3-4) after the sling is on the hook, wrap wire or heavy twine eight or ten turns around the two sides of the hook. Complete the process by winding several turns of the wire or twine around the sides of the mousing and tying the ends securely.
3-3. RIGGINGS AND DECK FITTINGS. There are two types of riggings: standing and running. Information on both riggings and deck fittings is as follows:
a. Standing Rigging. Standing rigging includes permanent and semipermanent structures and gear (Figure 3-5).
(1) The principal function of masts is to support cargo booms. Masts also support signal lights, antennas, and crow's nests. On most modern ships, each mast is fitted with a crosstree to which the topping lift blocks are secured, and a mast house, which supports the heel of the boom.
(2) King posts are two vertical supports, usually steel, one each side of the centerline of the ship used to support booms. King posts are also called Samson posts.
(3) Shrouds provide athwartship support for the mast or king posts. Two or more shrouds are used on either side of a mast or king post and are secured to the deck or bulwark in a fore and aft direction to provide maximum support.
Figure 3-5. Standing rigging
(4) Stays and backstays are heavy wire ropes similar to shrouds, found at the mast where the jumbo boom is located. When they support the mast or king posts from a forward direction, they are called stays; when they support from an aft direction, they are called backstays. Additional stays and backstays may have to be rigged when unusually heavy lifts are being loaded and discharged.
(5) Turnbuckles are internally threaded collars turning on two screws threaded in opposite directions. Turnbuckles are used to take up slack in the shrouds and stays.
b. Running Rigging. Running rigging (Figure 3-6) includes the moving parts of the ship's gear.
(1) A cargo boom is a spar extending from a mast or a king post. It is used as a derrick arm to handle cargo. Booms are sometimes referred to as derricks.
(2) The cargo hoisting wire rope or line reeved through the boom blocks and used for working cargo is the cargo runner. The runner is also called the cargo fall or whip.
Figure 3-6. Running rigging
(3) The tackle that raises and lowers the boom is the topping lift. Single and multiple topping lifts are used aboard ships.
(a). The single topping lift is a single wire rope 1 1/4 inches or larger running through a single-sheave topping-lift block at the crosstree on the mast or at the top of the king post. One end of the lift is shackled to the head of the boom and the other end to the bail.
(b) The multiple topping lift is a single wire rope reeved through a block at the head of the boom and a block at the masthead and made fast on the topping-lift cleat. The size of the wire depends on the safe working load of the boom, but 5/8- to 7/8-inch wire rope is usually used.
(4) The lines or tackle used to steady or swing booms are usually known as guys. When led to a source of power, however, guys are called vangs. Guys may be outboard, inboard, or amidship. An amidships is sometimes called the lay guy or the schooner guy.
(a) Outboard guys are made fast to the outboard side of the head of the booms and to fittings on the deck or bulwark. These guys are often referred to as the working guys because they are under greatest stress. The stress on the guys occurs when the load is being transferred athwartship or when it is being supported anywhere between the two boom heads.
(b) Inboard guys are made fast to the inboard side of the head of the booms and to fittings on the deck or bulwark. Since the load on the cargo hook is always between the heads of the two booms or directly under one of them, there is little or no stress on inboard guys.
(c) Amidship guys serve the same purpose as inboard guys -- they hold the booms together. They have the advantage of being up and out of the way when both booms are being worked together. Amidship guys consist of a light tackle between the heads of the two booms. The hauling part of the tackle is usually led through a lead block on the mast or king post and made fast to a cleat.
(5) The preventer is a wire rope used in addition to the guys to reinforce against additional strain. The preventer is usually made of 5/8- or 3/4-inch wire rope.
(6) The bail plate (topping lift) is a triangular steel plate with a hole in each corner to which are attached to the topping-lift wire, the bull chain, and the bull rope on a single topping lift.
(7) The bull chain is a heavy-duty chain having links 1 1/4 inches in diameter or larger. It is used on a single topping lift to hold the boom in its vertical working position.
(8) The bull rope is a wire rope used on a single topping lift to top and lower the boom.
(9) The topping-lift cleat is attached to the mast house or king post and is used for securing the multiple-topping lift wire.
(10) The head block is the block at the head of the boom through which the cargo runner is led to the cargo hook.
(11) The heel block is the block at the heel of the boom through which the cargo runner is led to the winch.
(12) The guy tackle consists of the blocks and tackle used on guys.
(13) The guy pendant is a short wire rope with a thimble or socket on each end. Guy pendants are used to attach the guy tackle to the head of the boom and to the deck or bulwark.
(14) The gooseneck is a metallic swivel joint that connects the heel of the boom with the mast or the mast house.
(15) Topping-lift blocks are blocks at the head of the boom, the crosstree on the mast, or the top of the king posts through which the topping-lift wire is reeved.
(16) A fairlead is a block, ring, or strip of plank with holds, serving as a guide for the running rigging or any rope to keep it from chafing and as a direct line to a source of power.
(17) The link band is a band around the head of the boom to which the topping-lift guys and headblocks are secured.
(18) The stopper chain is a piece of close-link chain about six feet long composed of links 1/4 to 1/2 inch in diameter. It is used to stop off the multitopping-lift wire when transferring the wire from the cleat to the winch and vice versa.
c. Deck Fittings. Deck Fittings (Figure 3-7) include the devices used to secure standard and running rigging.
(1) Bitts are used on ship for securing mooring or towing lines.
(2) Chocks are heavy fittings secured to the deck, used for the lead of lines. Types of chocks are closed, open, and roller.
(3) Cleats are metal fittings having two projecting horns welded to a vessel's deck and used for securing lines.
(4) Pad eyes are fixtures attached to a deck or bulkhead, having an integral baseplate and an eye to which lines or tackle may be fastened for securing or hauling cargo.
(5) Cleat and pad eyes are often attached to the bulwark. The bulwark consists of a raised plating along each side of the vessel above the weather deck. The plating is covered by a bulwark rail, which serves as a stiffener for the upper edge of the plating.
a. Electric Winches. An electric winch has a steel base on which the winch drum, motor, gears, shafts, and brakes are mounted. The drum is usually smooth with flanged ends and revolves on a horizontal axis. The drum is driven through single or double reduction gears by an electric motor (usually direct current). A solenoid brake and a mechanical brake are fitted to the motor shaft. The winch may be located on deck or on a deckhouse, and the cargo runner is wound on the drum.
b. Hydraulic Winches. The hydraulic winch has the advantage of smoother operation due to less jerky starts and stops and none of the overheating worries encountered in electric winch operations.
(1) Similar to the electric winch, hydraulic winch control handles are located on pedestals near the square of the hatch. From this position, operators can control the rotation and speed of cargo.
(2) The drive equipment of the hydraulic winch consists of an electric motor driving a variable displacement pump and a hydraulic motor that, through reduction gears, drives the shaft of the winch.
- Inspect the winch.
- Open control equipment ventilator covers.
- Turn the switch on the control box to the ON position. Before leaving the winch, the operator must make sure the switch is turned off to prevent accidental starting.
- Move the control handle forward to pay out cable and backward to haul it back in.
- Avoid swinging the draft. Swinging can be prevented in the hold or on the pier by plumbing the draft directly under the head of the boom before hoisting. Swinging in midair can be controlled by waiting until the draft is at the highest point of its outboard swing and then slacking the cargo runner on the hatch winch quickly so that the draft is directly under the head of the boom (Figure 3-8). Tag lines are used on long or oversize drafts for additional control.
- Avoid rapid starts and stops or sudden stresses. Sudden starts or stops may break a cargo runner, part guys or topping lifts, or carry away a block.
- Keep the right amount of slack in a cargo runner which is not under stress. Insufficient slack will cause the draft to strike against the side of the ship or the hatch coaming. Too much slack will allow loose turns to pile up on the drum.
- Keep the hook as close to the junction of the falls as possible.
- Keep the loads as close to the rail or deck as possible. Also, keep loads as low to the coaming as possible.
- Avoid severe tightlining of even very light loads, as a difference of only a foot or two in the height of the load may increase the stress tremendously.
- Keep the heads of the two booms as close together and as high as possible to reduce the tension on the falls and the guys. This procedure is effective at any given height in the junction of married falls.
- Turn off an electric winch if it becomes necessary to walk away from the controls.
- Ensure slings are as short as the draft permits. Slings that are too long permit excessive swinging of a draft resulting in a fiddlestring or tightline pull. This in turn causes excessive strain on the cargo falls and guys as the two winches pull against each other; it also causes a torque or twisting effect on the boom. If the fiddlestring pull is unavoidable because of the type of cargo being handled, a single swinging boom rigging should be considered.
a. Present cargo-handling methods require two winches for discharging or loading cargo. The winches or winch controls may be located in such a way that one winch operator can operate both, or the location may require two winch operators.
(1) The winch controls consist of a master controller or switchbox located on a pedestal near the end of the hatch square and a group of relays, contactors, switches, and resistors located near the winch motor.
(2) The control equipment regulates speed in both directions. The master controller is normally a five-speed, drum-type, reversing switch commonly found on modern cargo ships. An additional ON-OFF power switch is located on the controller box.
(3) The size of the winch motor depends on the maximum load to be handled on the booms and rigging. Heavier loads normally require changes in rigging and slower speeds. Although boom capacity may range from 5 to 60 tons, a 50-horsepower motor is commonly used on all winches. Since most lifts are 1 to 5 tons, the winches and the rigging are designed to handle these loads at the highest speed practicable. Because the winch motor is a series motor, increasing torque will reduce the speed for heavier loads up to the maximum load for the rigging arrangement.
(4) Most winches are equipped with a solenoid brake on the motor shaft. The brake is set by heavy springs and released by energizing the solenoid coil. When the master controller is moved through the various speed positions to the OFF position, relays are so arranged that dynamic braking occurs for short intervals and then, when the solenoid coil is de-energized, total braking occurs. At least once during every lowering operation, a load going downward at full speed must be retarded and brought to a halt, either when it reaches the deck or when held in the air. Although the speed could be retarded by the friction brake, the frequent wear and tear would require the excessive replacement of brake lining and could necessitate an oversize brake. Dynamic braking on the other hand slows down speed without causing wear on the brake lining and requires the magnetic brake only for final slowing or stopping of the load. For emergency use, a foot-operated brake or other mechanical brake is usually included.
(5) The operation of an electric winch is simple. The speed is determined by the position of the control handle, the amount of runner on the drum, the weight of the load, and the line voltage. In case of an overload, the circuit breaker turns off the electricity, but when the control handle is returned to the OFF position, power is immediately turned on again.
(6) Running an electric winch at slow speed over a long period of time causes the resistors to overheat and eventually burn out. By running the winches at a faster rate, the winch operator can avert such breakdowns.
(7) When preparing electric winches for operation, winch operators will-
b. Winch operators must also follow safe operating procedures. These procedures are an important part of winch operation. Operators must-
3-6. SIGNALS USED IN WINCH OPERATIONS. The winch operator cannot see the draft at all times; therefore, he must depend on the signalman for instruction. The safety and smoothness of the operation depend on the judgment of the signalman and the skill of the winch operator to respond; a team effort is essential.
a. Every member of the hatch section must be familiar with the signals used in cargo handling. Each signalman must know the safe methods of slinging cargo and must satisfy himself that the draft is slung properly before giving the winch operator a signal to move it. The signalman must learn to judge the few seconds that elapse between the time the signal is given and the actual stopping of the winch. If allowance is not made for this, accidents may results.
b. The signalman and the winch operator must clearly understand the signals in order to prevent accidents, confusion, and damage to the cargo or the cargo gear. The signalman must place himself in such a position that he can see the draft at all times and ensure that his signals can be clearly seen by the winch operator. Both the signalman and winch operator should continually observe the rigging, paying particular attention to slack guys, chaffing runners, loose pins in shackles, strained hooks, and any condition of slings and bridle which could be unsafe.
c. To signal for two winches, both hands are used. There must be a clear understanding between the winch operator and the signalman concerning which hand controls each winch. Figure 3-9 shows the standard hand signals for winch operations.
3-7. RIGGING STANDARD CARGO BOOMS. Before a ship may be worked, the booms must be topped (raised), guyed, and properly spotted. Each man in the hatch section should understand the procedures for topping, spotting, and lowering the booms.
- Ensure that the deck is well policed before rigging begins.
- Assign the necessary number of men to specific jobs and have all men stand clear of the deck under the booms.
- Require personnel to wear gloves.
- Inspect rigging and deck fittings.
- Supervise the placement of guy tackles.
a. Most of the newer cargo ships are equipped with separate topping-lift winches. Booms can be topped or lowered simply by operating the topping-lift winch. When topping and lowering booms, the hatch foreman must-
Figure 3-9. Signals used in winch operation
- Require nonessential personnel to stand clear when booms are being topped or lowered.
- Ensure that no personnel are standing where they could become entangled in lines about the deck.
- Inspect booms before starting work. Before applying power to a guy, be sure that the gooseneck is free to turn by heaving on the guy by hand.
- Not run cargo runners across the hatch coaming.
- Not handle drafts that exceed the safe working load of the rigging.
- Instruct military cargo handlers to take sufficient turns on a cleat or cathead while the boom is high to ensure having control of it when it reaches a low position.
- Avoid overloading or putting shock loads on the cargo gear when the boom is at a low angle.
- Avoid letting a loaded boom rest against a stay, shroud, or other fixed object as the resultant bending may cause the bottom to fail.
- Keep tension on married falls as low as possible during a lift.
b. When using cargo booms, operators will-
a. Multiple-Topping Lift (Booms in Cradles). The procedure for topping booms with multiple-topping lifts when the booms are in cradles is as follows:
(1) When topping booms with multiple-topping lifts, the hatch foreman will assign men to winches, guys, runners, topping-lift wire, and cathead. He will also assign one person to overhaul the runner as the boom is topped and assign persons to the outboard and inboard guy.
(2) The hatch gang will lay out guys to proper fittings and lay topping-lift wire along the deck or over the rail. The hatch gang will then place the hauling part of topping-lift wire in a wire rope snatch block and take five turns with topping-lift wire around the cathead in the direction opposite the cargo runner (underneath the cathead). Persons are assigned to clear the topping-lift wire and attend the cathead.
(3) The winch operator will raise the boom to the desired height by putting the control lever of the winch in position for lowering and take in the hauling end of the topping-lift wire which is wound around the cathead.
(4) To secure the topping-lift, the hatch gang will apply the stopper chain using the following procedure:
(a) With the stopper chain secured to a pad eye on deck, pass the running end of the chain around the topping-lift wire, making sure that at the completion of the turn, the running end of the chain passes under the standing end of the chain (Figure 3-10, 1).
(b) Run the running end of the stopper chain around the topping-lift wire again, making sure that this turn passes over the first turn (Figure 3-10, 2). The chain's running end should again go under the standing end at completion of the turn. This completes a double half hitch, rolling hitch, or stopper hitch (Figure 3-10, 3). Holding the stopper hitch tightly in place, take two half hitches above the stopper hitch.
(c) Wind the remainder of the chain around the topping-lift wire so as to bind the half hitches. Have one man hold the chain in this position (Figure 3-10, 4).
Figure 3-10. Steps in applying stopper chain
(d) With the turns still on the cathead, slack off the topping-lift wire slowly until the weight of the topping-lift is transferred from the cathead to the stopper chain.
(e) When the chain has the weight of the topping-lift, remove the turns from the cathead and secure the topping-lift wire to the topping-lift cleat by taking three round turns on the cleats followed by three figure eights.
(f) Tie or mouse the figure eights with a piece of rope yarn or wire. The remainder of the topping-lift wire can be coiled loosely around the cleat to keep it off the deck and out of the way.
(g) Remove the stopper chain.
(5) The winch operator will swing the booms to working position by hauling on the guys and spotting them according to the type of rigging desired.
(6) The hatch gang equalizes guys and preventers.
b. Single Topping Lift (Booms in Cradles). The procedure for topping booms with a single-topping lift when the booms are in cradles is identical to that for multiple-topping lifts with two exceptions:
(1) On vessels rigged with single-topping lifts, the catheads are equipped with a fitting to which the bull rope can be made fast. When this fitting is available, the bull rope is secured to it instead of five turns being taken around the cathead.
(2) The stopper chain is not used; instead, the topping lift is secured as follows:
(b) Slack off the bull line slowly until the chain supports the weight of the boom.
(c) Remove the bull line from the cathead and coil it around the cleat. It is only necessary to get the bull line off the deck and out of the way since it does not support the topping lift unless the boom is being topped or lowered.
c. Topping-Lift Winches. Most of the newer cargo ships are equipped with separate topping-lift winches. Booms can be topped or lowered simply by operating the topping-lift winch.
- Rewind runners smoothly on the drum of the winch and secure the cargo hook to a ring or a pad eye with a slight strain.
- Secure guys to the heel block or fittings on the mast table and pull them taut.
- Coil the hauling parts of outboard and inboard guys over the guy tackles and tie off the guys. Make amidship guys fast to the cleat on the mast.
- Secure topping-lift wires to the topping-lift cleat.
- Step 1. Swing booms slightly beyond the spotting position (approximately 2 to 4 feet).
- Step 2. Secure the preventer to a pad eye on deck.
- Step 3. Secure the outboard guy to a cleat on deck by making one figure eight with one hatch member remaining to hold the guy tightly.
- Step 4. Take all slack out of the amidship or inboard guys. The booms will swing inboard to the desired position. This action should nearly equalize the strain between the outboard guys and preventers, depending on how close together the guys and preventers are secured.
- Step 5. Place a strain on the outboard guys and preventers by lifting a light draft centered between the two booms.
- Step 6. Equalize the outboard guys and preventers by surging, or slacking off slowly, on the outboard guy until desired tension is obtained. Then secure the outboard guy.
- Step 7. Take out all slack in the amidship or inboard guys and secure them.
a. Multiple-Topping Lifts. The procedures for lowering booms with a multiple-topping lift are as follows:
(1) When lowering booms with a multiple-topping lift, the hatch foreman will assign persons to winches, guys, runners, topping lift, wire, cathead, and stopper chain.
(2) A member of the hatch gang will apply the stopper chain and transfer the wire from the cleat to the cathead, taking five turns in the same direction as the cargo runner (over the cathead).
(3) The hatch gang will remove all the topping-lift wire from the topping-lift cleat, except the three round turns, and carefully surge the topping-lift wire until the stopper chain supports the weight of the boom.
(4) The winch operator takes up on the winch until the strain is transferred from the stopper chain to the cathead. The hatch gang member removes the stopper chain, and the winch operator lowers the boom using the winch.
(a) While the booms are being lowered, men assigned to tend guys take in on the guy tackles and those assigned to tend the runner overhaul it to prevent turns from piling upon the winch.
(b) The ship's master may direct that booms be lowered into cradles and secured upon completion of the operation, or that they be secured in any other manner he mandates.
(5) When booms are down, responsible personnel will secure all gear as follows:
b. Single-Topping Lift. The procedure for lowering booms with a single-topping lift is identical to that for multiple-topping lifts except for the procedures listed below.
(1) Cargo handlers will transfer the weight of the boom to the cathead as follows:
(a) Remove the bull line from the cleat and secure it to the fitting on the cathead, if available, making sure that the bull line is led through a snatch block to the cathead and not directly to the cathead. If there is no such fitting, take five turns around the cathead in the same direction as the cargo runner (over the cathead).
(b) Raise the boom slightly to remove the weight from the bull chain and remove the shackle that secured the bull chain to the deck.
(c) Lower the boom by depressing the control handle of the winch.
(2) After the booms are down, secure the gear. The bull chains are then shackled to pad eyes, and bull ropes are hung over the topping-lift cleat.
c. Guying Booms. The procedures for guying booms are as follows:
(1) Methods of guying. There are two methods of guying the fixed booms of the yard-and-stay type of rigging. Operators may use outboard and inboard guys or outboard and amidship guys. The outboard and amidship guys are used more frequently. If the inboard guy is used, members of the crew must find a place on the deck or bulwark to secure it. Since the load on the cargo hook is always between the heads of the booms or directly under one of them, there is always less stress on the inboard or amidship guys than on the outboard guys. The lightweight amidship guy is sufficient to carry the stress and is raised aloft out of the way.
(2) Equalizing guys and preventers. Besides the regular outboard guy on the fixed boom, an additional wire is attached to the head of the boom and led to the deck to act as a preventer. Crews must avoid rigging the preventer so that the guy takes all the stress and the preventer takes stress only if the guy parts.
(a) The preventer is usually a single heavy wire while the guy has a manila or synthetic fiber purchase; therefore, the preventer and the guy will not share all loads equally. If the guy and preventer have equal tension under a light load, the guy stretches much more than the preventer under heavy loads so that the preventer has to take most of the increase. Crews can avoid this situation by adjusting the guy under a light load so that there will be a little more tension on it than on the preventer. Under a heavy load, then, the guy will stretch and let the preventer have its share.
(b) Crews should also secure the guy and preventer as close together as possible without fastening them to the same fitting. This is done because if the guy is in one place and the preventer in another, the desired equalization of tension between the two will not be achieved; under different degrees of tension the stress on one will increase more rapidly than on the other. Once the guys and preventers have been secured as close together as possible, the crew will equalize the guys and preventers using the following steps:
(c) If the guys and preventers are constructed of the same materials, they react to heavy and light loads equally. Therefore, when the guys and preventers are of identical material, the crew must slack off slightly on the outboard guys to equalize the strain, even with a light load. Slack off the outboard guys after the booms have swung inboard and nearly equalized the strain between the outboard guys and preventers. When the guy and preventer cannot be nearly parallel, the guy should be placed in the position of greater stress (more nearly in line with the fall) under most conditions.
(d) The crew must avoid slack in both the preventer and the guy. Otherwise, if one fails, the other fetches up with a jerk after the slack is taken out. Also, if unnecessary slack is allowed to develop in guys, booms map slap about.
(e) While there have been a few instances in which either the guy or preventer parted and the other held, the proper use of preventers has saved many a weak guy. Preventers should be considered useful only in keeping the guy from parting, not in holding the boom after the guy parts. A few vessels have heavy preventers (which are intended to carry the guy load) and very light guys (which are intended only for trimming the booms). Since these guys provide little additional strength, they should not be left slack. The crew should check manila guy purchases regularly since it shrinks when wet and stretches when dry; synthetic fiber lines are not affected by moisture.
(3) Positioning guys. The importance of properly guying booms with respect to the angles of stress cannot be overemphasized, particularly when using married falls. Overstressed guys could result in loss of time, cargo, cargo gear, and lift. Figure 3-12 illustrates three positions of the guy and boom, and Table 3-1 shows how strains vary with these positions. In Figure 3-12, "A" denotes that the guy is in line with the fall, "B" that the guy is at a right angle to the boom, and "C" that the guy is behind the heel as far as it is possible to place it without topping.
(a) The greatest drift and the lowest possible strain result when the amidship boom is angled far inboard and the guy is placed at a right angle to the boom (Figure 3-12, boom position 3, guy B).
(b) With the amidship boom head over the coaming (Figure 3-12, boom position 2) or outboard of it (Figure 3-12, boom position 1), the guy should be led as far back of the heel as possible without topping (Figure 3-12, boom position 2, guy C, and Figure 3-12, boom position 1, guy C).
(c) The greatest strain results when the amidship boom angles outboard and the guy is in line with the fall (Figure 3-12, boom position 1, guy A).
Table 3-1. Strains on cargo gear at various guy positions
(Load, 1 short ton; falls, 30 degrees from horizontal)
(d) Figures 3-13 through 3-16 show the after end of number 4 hatch on a C3 cargo vessel. The gear has been trimmed to work the near end of the hatch with the up-and-down boom in a fore-and-aft line through its heel and the guy in line with the fall. The figures and paragraphs following deal mainly with the swinging boom and outboard guys and only briefly with the inboard gear, since experience shows that it is with the first two outboard guys that failure in capacity usually occur.
(e) Figures 3-13 through 3-16 also show a 1-ton load suspended at various load positions using two booms and married falls. The weight of the load is given next to the amidship boom in each figure. This weight, when lifted on a single swinging boom, would produce approximately the same strain (compression) as the 1-ton load shown in that figure.
(f) Even with a fall angle of only 90 degrees, occurring where the junction of the falls is about 20 feet above the deck (Figure 3-13), the tension on the outboard guy of the stay boom is 1.6 tons, and the swinging boom supports the equivalent of 2.1 tons. The stresses go up (Figures 3-14 and 3-15) as the 1-ton load is raised until the angle between the falls reaches 150 degrees (Figure 3-16), when the tension on the outboard guy of the stay boom is 6.2 tons and the equivalent load on the swinging booms is 6.4 tons. The principle explains why a boom which has been tested with a swinging load of 7 tons will sometimes fail under a load of only 3 or 4 tons which is being supported by two booms. Unless otherwise stated, "5-ton SWL" stenciled on the heel of a boom refers to a load on a swing boom, not one being lifted by using married falls.
(g) The strain on the falls in Figures 3-13 through 3-16 varies with the angle between them produced by each load position. Figure 3-17 shows this principle in more detail. As the angle between the falls increases, the strain on each fall increases according to the percentages shown. Once the angle between them increases beyond 120 degrees, just a small change in the angle causes a massive increase in the strain exerted on each fall. For example, Figure 3-17, D, shows only a 20-degree increase in angle (from 120 degrees to 140 degrees) which causes a 41 percent increase in the strain exerted on each fall. In Figure 3-17, F, a 10-degree increase in angle (from 150 degrees to 160 degrees) causes a 94 percent increase in the strain exerted on each fall. Finally, in Figure 3-17, H, a 5-degree increase in angle (from 170 degrees to 175 degrees) causes a 576 percent increase in the amount of strain exerted on each fall. A load held with a 175 degree angle between falls exerts a strain equivalent to 1,146 percent or 11 1/2 times the weight of the original load on each fall. The terminal operations specialist can use the figures given here by multiplying the weight of a particular load by the percentage shown, and multiplying that figure with the approximate angle at which the load is suspended.
(h) The additional pull exerted on the falls as the angle increases is mainly a horizontal pull that tends to move the two supporting booms toward each other. Table 3-2 lists the tension on each fall at various fall angles, both as a percentage of the weight of the load (column b) and in pounds (column c), and shows how much of that tension is a horizontal pull tending to bring the boom heads together (column d). With a heavy load, the final angle of the falls will be smaller than in the case of a light load, since the winch can more easily "tightline" a light load (Figure 3-17, H) than a heavy load. Tightlining occurs when the angle between the falls approaches 180 degrees. A lighter load suspended at a higher height will produce a greater horizontal pull than the heavier load which stalls a winch at a lower height.
(i) Table 3-2 and Figures 3-12 through 3-17 illustrate that severe tightlining of even very light loads between two booms is dangerous because a difference of only a foot or two in the height of the load (increase in the fall angle) may increase strain tremendously. Use the following techniques to minimize the degree of angle between married falls:
- Use slings which are no longer than necessary.
- Keep the hook as close to the junction of the falls as possible. If chain is used for additional weight, hang it in a bight beside the hook rather than between the hook and the junction of the falls.
- Keep loads as low as possible, but maintain sufficient height for them to clear the ship's rail.
(4) Topping or jackknifing of booms. Topping occurs when strain is placed on a boom resulting from incorrectly positioned guys. A topping or jackknifing boom can cause considerable damage to the ship's gear and result in loss of life. Responsible personnel should determine whether or not the guys are properly placed to prevent topping of a boom. Figure 3-18 shows the visual test personnel should use to help determine if booms will top.
(a) To determine if the outboard boom can top, sight from the pad eye (Figure 3-18, A) where the lower end of the outboard boom's outboard guy is secured, to the head of the amidship boom (Figure 3-18, B); if the line of sight passes behind the heel of the outboard boom (Figure 3-18, C) the boom can top. If the line of sight is ahead of the heel and below the outboard boom, it will not top. If the line of sight is ahead of the heel but above the boom, it will top only until it reaches the line of sight.
Figure 3-18. Determining if outboard boom can top completely
(b) To determine if the amidship boom can top, stand at a point near the ship's rail where the distance from the heel of the amidship boom to the head of the outboard boom can be sighted. If the outboard guy of the amidship boom passes above the line of sight, the boom will top (Figure 3-19). If the outboard guy of the amidship boom passes below the line of sight, the boom will not top.
NOTE: There is one exception to the rules in paragraph (b) above. When the heels of the booms are far outboard from the centerline, placing the guy in the manner just described to prevent the outboard boom from topping all the way will result in the guy being nearly parallel to the boom. This puts the guy under extreme tension and may result in the failure of either the guy or the boom. In this case the guy should be left well back of the heel of the boom where the stresses are minimal, and the preventer should be placed well ahead of the heel, with a foot or so of slack. This slack is an exception to the general rule for preventers. When the boom tops up, which is likely, the preventer will limit the amount of rise.
a. Yard-and-Stay Rig. The yard-and-stay system (Figure 3-20) is used for loading and discharging cargo, particularly when a new winch operator or heavy drafts are involved. This rig is sometimes referred to as the union, married falls, or burton system.
(1) Using the yard-and-stay method of rigging, the operator spots one boom over the center of the hatch (referred to as the amidship boom, the stay boom, or the hatch boom) and the other boom over the side of the vessel (referred to as the outboard boom, the yard boom, or the burton boom). The ends of the cargo runners are shackled or married to a single cargo hook.
(2) In discharge operations, responsible personnel attach the cargo to the cargo hook in the center of the hatch. The draft is lifted directly up by the cargo fall of the boom spotted over the hatch. At the same time, the slack in the other fall is taken up. As the draft reaches the desired height above the coaming, the lifting cargo fall is stopped and then slacked off while the fall on the outboard winch continues the lifting operation. This action carries the draft of cargo over the side of the vessel. The outboard winch then lowers the draft to the pier. In loading cargo, the operation is reversed.
b. Farrel Rig. A major improvement in the yard-and-stay method of rigging the ship's gear for burtoning cargo had been made in recent years. This method involves using the farrel rig (Figure 3-21). The procedure consists of placing the heels of the outboard guys (vangs) on a common axis or making them coaxial. Topping-lift winches are installed and the hauling part of the topping list is reeved through lead blocks secured near the ship's centerline.
(1) Once the guys have been secured to the short vang posts and pulled tight, there is no need to tend guys. The boom head moves vertically along a straight line parallel to the centerline of the ship. With this setup, all that must be done to top or lower the boom is to press the button controlling the topping-lift winch.
(2) The addition of topping-lift winches makes this rig more useful. With the guys led to power, it is possible to swing the boom in either direction under power, thus providing complete power positioning of the unloaded boom.
c. Ebel Rig. The ebel rig (Figure 3-22) was designed to handle loads up to the full capacity of 5- and 10-ton booms by the burton system, provide for complete power positioning of the unloaded booms, eliminate manual handling of lines, and increase safety. Figure 3-23 shows the arrangement of the topping lift on the 5- and 10-ton booms. The topping lift is offset inboard near the centerline of the ship to control the swinging of the boom in the outboard direction. The hauling part of the topping lift is led down the inboard side of the king post through a lead block to the drum of one of the topping-lift winches mounted on the king post.
(1) Figure 3-23 shows the arrangement of the mechanical guys on the 5- and 10-ton booms. When rigging the 5-ton boom, the standing part of the guy is secured to the extreme outboard end of the crosstree and runs over a sheave at the head of the boom, down to a sheave at the bulwark, back around the second sheave at the head of the boom, through a lead block, and then down the outboard side of the king post to the drum of the electric guy winch mounted on the king post. No vang posts are necessary because the guy is secured to the deck or bulwark.
(2) The ebel rig is designed so that the effective guy resultant force keeps the stresses moderate, even when 5- and 10-ton loads are being handled. If the draft is hoisted to excessive heights, the outboard boom head rises by riding up the bight of the guy tackle until it reaches a position of equilibrium with the load. While the boom head rises, the draft remains almost stationary. The angle between the two falls is thus limited to a fixed predetermined maximum, and no part is overloaded. When the draft is lowered by slacking off on the falls, the boom resumes its normal position by riding down the bight of the guy. Since the boom is never free from the tensioned guy, it cannot drop freely. When moving (burtoning) 5 tons, the minimum height of the married fall above the deck at which the outboard boom will ride up is about 30 feet. For lighter loads, it is higher. The drift is ample to handle almost any draft.
d. West Coast Rig. The west coast method of rigging (Figure 3-24) is a modified form of the yard-and-stay method and is the most common rig used by the military. This operation differs from the yard-and-stay method only in the way the amidship boom is spotted and the winches are operated. The amidship boom is spotted approximately halfway between the hatch coaming and the ship's side. The particular advantages of the west coast rig are the speed and ease with which the draft can be landed on either side of the hold or between deck close to the point of stowage. Operators must be skillful in winch operation because the draft is raised from the hold or lowered into the hold, supported equally by both runners. Normally, this type of operation requires only one winch operation, but two operators may be needed depending on the location of the winch controls.
e. Wing-and-Wing Rig. Another modification of the yard-and-stay method of rigging is the wing-and-wing method (Figure 3-25) which differs in the way the booms are spotted and the winches are operated. Both booms are spotted over the side of the ship, one boom on each side. Operators then equalize the booms in the same manner as the outboard boom in the yard-and-stay rig. The load is lifted from the hatch supported equally by both runners. Operators must use winches skillfully to avoid tightlining.
(1) The wing-and-wing method is especially useful when it is necessary to handle loads on both sides of the ship while loading or discharging. It is used mainly in LOTS operation.
(2) This rig can be used to work cargo in the hatch, but unless the coaming is equipped with rollers, the cargo runners will chafe against the coaming wearing out the wire and butting grooves into the coaming.
- Reeve the gantlines (a length of rope, 3 1/2 inches in circumference) through the 10-inch wooden block secured to the link bank at the head of each boom.
- Hoist the tent aboard ship using the ship's fall.
- Tie the hatch boom gantline to the large shackle attached to the metal shoe in the rear peak of the tent. Operators will spread out the tent while it is being raised. The hatch runner is inserted in the opening between the ridges of the tent and then the hatch gantline is heaved up until the bottom of the tent is above the deck. The heavy backstay of the tent is pulled taut, and the gantline is secured.
- Spread the tent over the hatch opening. The guy lines on the corners and center of the sides and back are tightened and secured. The intermediate lanyards are adjusted to keep the tent straight and to prevent sagging.
a. Hatch tents are large canvas shelters suspended from the heads of the booms to protect cargo and personnel during inclement weather. Hatch tents are frequently used in areas which have a rainy climate. They may also be used for shade during extreme heat, especially when discharging refrigerated cargo. Hatch tents give only particle protection, so when work is discontinued, responsible personnel should ensure that the hatch is closed and battened to give the cargo better protection. The seattle hatch tent is the best all-purpose hatch tent because it completely covers the hatch and is designed with reeve points and laced-up flaps. Before rigging the seattle hatch tent, the booms must be lowered. Operators will then attach a 10-inch wooden block to the head of each boom on the offshore sides of the link band. From the pier, the blocks will appear on the sides of the booms away from the pier.
b. To rig a seattle hatch tent, the rigging crew will-
3-12. RIGGING SAVE-ALLS. Save-alls prevent the loss of cargo overboard during loading and discharging. The rigging crew should rig save-alls at each working hatch and beneath each gangplank, skid or conveyor. The most common type of save-all is a rope net. The type save-all used in the general hatch set is made of manila rope and is 20 by 40 feet, with 8-inch square meshes. If a standard save-all is not available, substitutions may be made. For instance, wire or rope cargo nets may be lashed together or wooden platforms can be constructed and made fast between the ship and the pier under the working area.
- Attach the cargo hook approximately 3 to 4 feet below the top center of the save-all net. Hoist the save-all net over to, slightly above, and then over the ship's railing.
- Secure the lanyards and lashings of the save-all net to the cleats or pad eyes on board ship.
- Lower the net, release the cargo hook, and secure the bottom of the save-all to the stringer on the pier.
a. Responsible crew will rig a save-all using the ship's falls as follows:
b. Riggers should leave enough slack in the save-all to prevent it from being carried away when the tide or current moves the ship higher, lower or away from the pier. Where extremely high tides are common, the lashings should be slacked off or tightened frequently during the change of tide.
a. Most ships are equipped with booms having a safe working load of at least 5 tons. The capacity of cargo booms is usually marked on the boom heel. If the safe working load is not marked on the boom, the ship's officers on watch should have this information.
b. Winches vary in capacity. The exact capacity (leadline pull) is found on the manufacturer's nameplate on the machine. Otherwise, a ship's officer should know this capacity.
c. Whenever the load to be hoisted by the yard-and-stay rig exceeds the safe working load of the rigging, use an alternative rig that will increase the safe working load.
d. Wire rope of 5/8-inch and 3/4-inch diameter is most commonly used for cargo runners, but some vessels are equipped with 7/8-inch runners. The safe working load of 5/8-inch, new improved plow-steel wire rope is slightly more than 3 tons; 3/4-inch wire, slightly more than 4 tons; and 7/8-inch wire, slightly more than 6 tons. These safe working loads are for new wire. If the wire has been in use for some time or shows signs of wear, the safe working load must be reduced accordingly.
e. There are many methods of rigging standard booms for heavy lifts. Almost all methods involve doubling up the cargo runner. This process not only doubles the safe working load that is picked up by the cargo runner, but it also decreases the strain on each winch by half. For a lift over 3 tons, 5/8-inch wire is doubled up. Although it is not necessary to double up a 7/8-inch runner to lift a 5-ton load safely, it is necessary to double it up so that the winch will pull the load.
f. Operators must use skill, judgment, and common sense in operating cargo booms rigged for heavy lifts. Signalmen and winch operators must understand that the load should be plumbed underneath the boom before it is picked up. They must know the importance of tag lines in checking the swing of heavy drafts and must be familiar with the safe working load of all types of rigging and slings.
g. In working heavy lifts, responsible personnel must check all standing and running rigging and deck fittings frequently to detect unusual wear or chafing. Operators must ensure the safety of their equipment.
(1) The cargo runner is firmly secured to the drum of the winch. This can be done by reeving the end of the runner through the hole in the drum of the winch, out through the opening in the side of the drum, and twice around the shaft. The runner may be secured either with a rope yarn or wire clamps, but the latter method is recommended. As an additional precaution, winchmen should never operate with less than three turns around the drum of the winch.
(2) Shackles, hooks, and gates of snatch blocks used in rigging are secured with wire or rope before operation. These items should be checked during operation to ensure that they remain in safe condition. In mousing a shackle, operators will tighten and secure the pin with rope or wire.
(a) In all cases where rigging is aloft, wire should be used for mousing. Responsible personnel should use care in not placing mousing where it may be cut by the wire rope as it passes the shackle.
(b) Operators should mouse hooks to prevent slings from slipping off the hook and to prevent hooks from slipping off rings and other fittings. Hooks may be moused with rope or wire, and shackles may be used on certain types of hooks.
(c) Operators should be aware that, unless firmly moused, the gates of snatch blocks may open, allowing the wire to jump out. Many snatch blocks are fitted with a locking pin which, if available, should be used.
h. In making a heavy lift, all personnel in the hatch section must be alert for failures in the gear and other possible hazards. Bridles, slings, and other lifting devices must be thoroughly inspected. The safe working load of any rigging is limited by the safe working load of the weakest part of the rigging; this includes the slinging or lifting devices. The time and effort spent to rig booms for a safe working load of 10 tons would be wasted if an attempt were made to pick up a 10-ton lift using a 5/8-inch wire rope sling.
i. Operators should pick up a few inches of a heavy lift and inspect it before it is hoisted. The slings should also be checked and, if necessary, the draft should be lowered and the slings adjusted or blocked off with dunnage to prevent chafing of the wire or damage to the lift. While the load is suspended off the deck, operators should observe the rigging (including the booms, topping lift, runners, and guys) for indication of unusual strain.
j. After operators find everything in order, they should hoist the draft slowly in one continuous operation. All blocks should be running free. Operators should listen to the gear while the lift is being made. A faulty block, wire, or rope under strain sometimes squeaks and groans enough to give warning.
k. When using the jumbo booms, operators will lower the boom to the lowest position, enabling it and any draft to safely clear all obstacles. Operators should avoid swinging the boom at a near vertical angle.
l. Guy winch operators and personnel handling the guys on a jumbo boom should have the signalman in clear sight at all times and should be instructed to stop heaving if at any time the stress on the hauling part appears to be excessive.
m. Operators should check with the mate before making a heavy lift with the jumbo boom to find out whether auxiliary stays need to be set up.
3-14. HEAVY-LIFT BOOMS. Tanks, landing craft, tugs, picket and patrol boats, and other extremely heavy cargo required by the Armed Forces in the field present complex problems in cargo-handling operations. At loading terminals in the Unites States, operators may find loading a heavy lift to be fairly simple. However, at overseas bases, shoreside equipment or floating cranes are not always available. Often the ship's gear must be used for discharging heavy lifts. Many modern ships are equipped with one or two jumbo booms having capacities of 50 to 120 tons. These booms are generally located at the larger hatches of the vessel. Many ships used in task-force operations, particularly in securing beachheads, are equipped with heavy lift gear at practically all hatches for quick discharge of heavy equipment such as landing craft, tanks and bulldozers. A few American ships specially fitted for heavy lifts have jumbo booms with capacities up to 240 tons. All terminal operations personnel operating in the field will have occasion to operate heavy lifts. For this reason, the rigging and operation of the jumbo boom must be understood.
- Lead the cargo runner through a heel block to one winch at the hatch being worked.
- Lead the topping lift through another heel block to the second winch at the hatch being worked.
- Shackle the two guys to pad eyes, and lead the hauling parts of the guys through a series of snatch blocks to the additional sources of power.
- Making the breasting-up line fast to the boom, either by passing it around the boom or shackling it into a pad eye that may be on the boom for this purpose. Users should then pass the line through a snatch block on the mast and fairlead it to the cathead on the winch.
- Taking a strain on the breasting-up line and releasing the collar or lashing that holds the jumbo boom in place.
- Slacking off the line slowly until the weight of the boom is on the topping lift.
- Removing the breasting-line and lowering the boom into position with the topping lift.
a. Most heavy lift booms are full rigged with topping lifts, purchases, and guy tackles already secure. In order to save space on deck for cargo, the jumbo boom is generally carried in an upright position against the mast (Figure 3-26).
b. The first step for operators rigging the jumbo boom is to lead all purchases to power. Sources of power are required for the cargo fall to raise and lower the cargo hook, the topping lift to raise and lower the boom, for each guy tackle to swing the boom from the hatch opening to the pier and return.
(1) If only two winches are located at a hatch, operators may obtain the two additional sources of power from the warping winch, or winches, at an adjacent hatch. On double-rigged hatches, the winches on the opposite end of the hatch are used.
(2) When using sources of power, operators will-
c. At this point users should have led all purchases to power and made the guys fast; however, the boom is still held fast to the mast. Users should check, secure and tighten the shrouds and stays if necessary.
d. Users should them remove the collar or lashing that holds the boom to the mast by taking a strain, if possible, on the topping-lift wire to release the pressure on the collar or lashing. In vessels where this is not possible, users may employ breasting-up line by-
NOTE: Personnel must be sent aloft to release the boom.
- Blocks are running free.
- No lines are chaffing.
- The turns on the winches lie evenly.
- Snatch-block gates are securely moused to prevent opening.
- Guy tackles are free of twists and are guided through fairleads to sources of power.
- Stays are secured and tightened.
e. Users should be familiar with the following procedures for guying heavy-lift booms. The rated capacity of a boom is the safe load that it will lift when it is properly rigged, guyed, and operated and when the stays are properly placed. Responsible personnel should use care in rigging to prevent undue strain on the boom and the guys.
(1) On single-rigged hatches, personnel should use the anchor windlass for the forward jumbo boom and the mooring or warping winch for the after jumbo boom. They may do this by leading one guy over the top of one cathead and the other guy underneath the other cathead so that one guy is pulling while the other is slacking off. Experienced personnel should tend the guys. All personnel should understand the direction of rotation of the winch or windlass so that when the proper signals are given, a slow, smooth operation will result with minimum strain on the take-up guy. On double-rigged hatches, personnel may lead the guys to the winches on the opposite end of the hatch.
(2) As the guys approach the vertical, the strain on the guys and the boom increase while the angles between the guys and the boom decrease. To place the guys properly, operators should give the guy with the greatest strain the largest angle between the guy and the boom. Figure 3-27 shows the horizontal strains involved when the guys are placed on a heavy-lift boom for loading from or discharging to a pier. In this figure, users may assume that the ship is being unloaded. The outboard guy has been so placed that the angle between the guy and the boom is 15 degrees. A 3,000-pound pull is placed on the inboard guy while the brakes are applied on the outboard winch. The strain would be of about 4,230 pounds on the inboard guy and 11,580 pounds on the outboard guy. Decreasing the angle between the outboard guy and the boom by 10 degrees triples the strain. Shifting the outboard guy too far forward will cause too steep an angle with the boom, particularly if the boom has to be raised to handle cargo in the after part of the hatch.
f. Before operating the jumbo boom, users should familiarize themselves with jumbo boom operations by swinging the standard hatch booms clear of the working area. Generally, it is sufficient to swing these booms against the shrouds and secure them with their guys or it may be necessary to top them when working deck cargo. Users should also check gear thoroughly to ensure that--
g. Operators should ensure that signalmen, winchmen, and personnel tending guys clearly understand all signals. Additional signalmen may be needed to relay signals to personnel tending guys at the windlass or warping winches. However, the number of signalmen should be kept to a minimum.
h. Operators should sling the draft carefully and shackle the slings into the traveling block on the cargo runner. After a final check to see that everything is secure, they will then hoist the draft a few inches off the deck and recheck all rigging.
i. Operators should avoid faulty winch operations, sudden stops, and quick starts. Properly planned heavy-lift operations move slowly and smoothly.
j. Operators will carefully hoist the draft until it clears the hatch coaming and rail.
k. Operators will adjust the angle of the boom by taking up or slacking the topping lift.
l. Every change in direction of the boom requires an adjustment of the guys. As the boom is raised, responsible personnel should slack off the guys; as it is lowered, these personnel should tighten the guys.
m. The boom is swung by taking up one guy and slacking the other. When working a jumbo boom, operators should give close attention to handling the guys. When a boom is swung either inboard or outboard, one guy is the hauling guy and the other is the following guy. Operators should maintain the right amount of slack in the following guy to prevent undue strain on the hauling guy. Too much slack in the following guy might allow the draft to get away.
n. The uniform system of signals recommended for use in directing jumbo boom operations is shown in Figure 3-28. The signals in use should be posted at the operator's position at the signal control points and at such other points as necessary to properly inform those concerned. When hand signals are used, only one person should be designated to give the signals to the operator. The signalman must be located so as to be clearly visible to the operator at all times. Only persons who are dependable and full qualified by experience with the operation being directed should be used as signalman. A warning device or signalman should be provided wherever there is danger to persons from moving equipment.
- Swinging the boom to the centerline of the ship.
- Raising the boom until it is nearly vertical (about 85 degrees), and at the centerline of the ship. A limit switch is used to cut off topping winches when the boom is raised to 85 degrees above horizontal.
- Suspending the lower cargo hoist block to a position that is easy to reach from the winch house.
- Securing the handling pendant to the lower cargo hoist block and raising the lower block to about 10 feet from the upper cargo block, then passing the pendant through the opening in the king posts and outboard to portside of the cargo hoist hauling part.
- Hauling in on cargo falls until the boom head cargo blocks rotate and the boom passes through the opening of the king post to reposition itself at 85 degrees toward the adjacent hold.
- Reversing this procedure to move the boom back from the adjacent hold to the original hold.
o. When the unloading of one hatch is complete, responsible personnel should shift the jumbo boom to the next hatch by-
3-15. MODERN JUMBO BOOMS. Technological advances have increased the ability of a single jumbo boom to handle heavy cargo loads at either of two adjacent holds. These booms have been put on a limited number of new ships; they may also be installed on ships already in operation.
- Swinging the boom to the centerline of the ship.
- Raising the boom until it is nearly vertical (about 85 degrees), keeping the boom at the centerline of the ship. A limit switch can be set to cut off topping winches when the boom is raised to 85 degrees above horizontal.
- Suspending the lower cargo hoist block to a position accessible from the winch house.
- Securing the handling pendant to the lower cargo hoist block and raising the lower block to about 10 feet from the upper cargo block; then passing the pendant through the opening in the king post and outboard to portside of the cargo hoist hauling part.
- Hauling in on cargo falls until the boom head and cargo blocks rotate and the boom passes through the opening of the king post to reposition itself at 85 degrees toward the adjacent hold.
- Reversing this procedure to move the boom back from the adjacent hold to the original hold.
a. Operators may accomplish the adjacent hold operation with one boom and related gear located between the two hatches. The boom is stepped on a ball-and-socket heel assembly and is supported at its upper end by twin topping lifts from rotating heads on two unstayed king posts. The boom heel has a ball pivot fitting which permits a 3 degree port or starboard tilt of the boom head when being passed between king posts to the opposite hatch. Each of the two topping lifts has a winch. The split topping arrangement provides quick and accurate positioning of the boom throughout its travel of the vessel, either inboard or outboard. The upper block of the cargo falls is supported from a rotating sleeve near the base of the boom. The lower block of the cargo falls is weighted and fitted with a hook or other attachment, as desired.
b. Operators position the boom by operating the topping lifts. The desired position of the boom may be reached by operating the topping-lift winches so as to properly take in or pay out on the topping lifts.
c. Operators will shift the boom from one hold to another by-
- When only a single boom is rigged at a hatch,
- When one boom is damaged and cannot be used.
- When it is necessary to load or discharge oversize light drafts.
- When one of the ship's winches needs repairs.
- The cargo runner on the boom not being used is run off the drum of the winch, and the boom is swung out of the way. The topping-lift wire of the working boom is fastened to the drum of the winch after the cargo runner is removed.
- The winch serving the working boom is used to raise and lower the cargo runner on the working boom.
- Two guys are used to swing the boom from side to side. Both guys are secured at the head of the boom leading to the pad eye ring on deck or on the rail. Power to move the boom from side to side is furnished by using another set of winches, one for each guy. If power is not available, the boom is swung by hauling on the guy tackle by hand.
a. To rig a single swinging boom on a standard vessel so that the boom is raised or lowered during the operation, the operator must ensure that-
b. A single swinging boom is rigged to handle loads within the safe working load of the cargo runner, but it is often necessary to lift loads that exceed the safe working load of the cargo runner. Loads that are within the safe working load of the boom, but which exceed the safe working load of the cargo runner, may be safety lifted by rigging the boom as follows:
(1) Top the amidship boom and swing it out of the way, and lower the outboard boom to the boom rest.
(2) Fasten the topping-lift wire and the guys.
(3) Equip the outboard boom with a runner long enough to permit doubling up. An additional 14-inch block is required.
(4) Reeve the end of the cargo runner through the 14-inch block and secure the block by either of the following methods:
(a) Using a boom with a doubling-up pad eye. Some booms are equipped with this type of pad eye (Figure 3-29) about 4 feet from the head of the boom in line with the pad eye splice in the cargo runner is shackled into the doubling-up pad eye. If available, a swivel may be made fast to the doubling-up pad eye, and the end of the cargo runner may be shackled into the swivel. This reduces the tendency of the wire to twist by taking the turns out of the wire at the swivel.
Figure 3-29. Doubling-up cargo runner
using doubling-up pad eye
Figure 3-30. Doubling-up cargo
runner using bottom of the block
(b) Using double becket blocks when available. Most cargo blocks used aboard vessels are double becket blocks. These blocks are constructed so that shackles and swivels can be attached to both the top and bottom of the blocks. Where these blocks are in use and there is no doubling-up pad eye on the boom, the eye splice in the cargo runner can be shackled into the bottom of the cargo block (Figure 3-30) or into a swivel attached to the block. It must be remembered that the shackled or swivel at the bottom of the block must have a safe working load of at least half the weight to be lifted. A 5-ton lift would require a shackle 3/4-inch or larger.
(5) Operate the boom in the same manner as the single swinging boom, single-rigged.
(6) If it is not impossible to double up the rigging using either of the methods described in paragraph (4)(a) and (b), secure the runner to the boom by taking two complete turns on the boom about 4 feet from the head and securing the eye splice to the link band (Figure 3-31).
3-17. YARD-AND-STAY RIG WITH DOUBLE PURCHASE. Doubling up with a swinging boom (Figure 3-32) greatly increases the time required to transfer the load from the pier to the ship or vice versa. Operators can save time by using fixed booms rather than changing to a swinging-boom operation. This is especially important when many loads just over the safe limit are to be handled. These loads can be handled at about half the rate of ordinary 1- or 1 1/2-ton drafts; light filler cargo can be handled without stopping the operation to single up the rigging. One of the easiest methods of augmenting the load limits is to rig both booms with a double purchase. This step requires two additional 14-inch blocks. In working this rig, guys and preventers must be in excellent condition and equalized as nearly as possible.
Figure 3-32. Yard-and-stay rig with a double purchase
a. The cargo runner of each boom is double up using either of the methods mentioned previously. If the doubling-up pad eye or the boom is used, the hauling part of the cargo runner must be on the inside. If the cargo runner is secured to the boom by turns, the turns must be started on the inside of the boom so that the hauling part of the runner is on the inside. These precautions prevent the hauling part from chafing against the standing part because the hauling part leads from the heel block to the head block.
b. When both booms have been doubled up, the two traveling blocks are married by shackling in a standard cargo hook assembly. The booms are topped, spotted, and worked as in a regular yard-and-stay operation.
a. Operators can handle heavy lifts at a hatch rigged with two pairs of standard cargo booms by rigging all four booms as shown in Figure 3-33, and performing the following steps:
(1) Lower the cargo hook on the nonworking set of gear and remove the cargo hook assembly.
NOTE: In this chapter, nonworking means not being used in the operation only. Gear in all other senses is operational.
Figure 3-33. Block-in-bight method of rigging four booms
(2) Place two additional 14-inch deep-throat blocks on deck and attach them to the cargo hook assembly.
(3) Lower the cargo hook of the working set of gear and remove the cargo hook assembly.
(4) Reeve the hatch runner of the working set of gear through a 14-inch deep-throat block and shackle the eye to the hatch runner of the nonworking set of gear.
(5) Reeve the outboard runner of the working set of gear through the other 14-inch deep-throat block. Then shackle the eye to the eye of the outboard runner of the nonworking set of gear.
(6) Raise the runner on the nonworking set of gear until the shackles (where the eyes are attached) are 3 to 4 feet from the head of the booms. (This step requires two winch operators.)
(7) Shut down and secure the winches on the nonworking set of gear.
NOTE: While the winch operator of the nonworking set of gear raises the runner, the winch operator of the working set of gear must slack off on his runner.
(8) Be sure that booms are properly spotted and guys and preventers are equalized.
b. Operators may now load and discharge heavy lifts not exceeding the safe working load of two parts of the cargo runner, the guys and preventers or the combined safe working load of two booms using the usual yard-and-stay method. This type of rigging has the advantage of being quickly rigged without the necessity of lowering booms. Only two winches are required, and the gear may be readily singled up for ordinary light drafts.
c. Many modern vessels are equipped with topping-lift winches which are used only for topping or lowering the booms. When the operator spots the boom, he shuts off the winch with the topping-lift wire remaining on the winch. This action permits the booms to be raised or lowered rapidly simply by operating the topping-lift winches. Almost all heavy-lift operations require a dragline operation. If topping-lift winches are available, double-rigged hatches may be rigged with the block-in-bight method as follows:
(1) Lower the booms in the after end of the hatch and remove the runners and headblocks from the booms.
(2) Reeve the cargo runners of the forward booms through 14-inch blocks, and shackle the runners to the link band of the opposing booms.
(3) Marry the two doubling-up blocks for regular yard-and-stay operations and raise the after booms to the desired height.
(4) Spot the booms and make certain that guys and preventers are equalized.
(5) Work heavy lifts as described in paragraph 3-19a using the winches at the forward end of the hatch. The winches at the after end are available for dragline operation only.
d. Operators can rig using the method described in paragraph 3-19a much faster than that described in paragraph 3-19b, but this method is for emergency use only. The time lost in lowering and raising the booms by using the topping-lift winch will be more than made up by having two winches available for dragline operation. Operators can move lifts landed in the hold to their stowage place in the ends or wings of the hold during loading or into the square of the hatch during discharge. Operators can proceed with the dragline operation while the previous load is moving to or from the ship and while the crew are hooking on the next load or unhooking the previous load.
a. Winch operators must be highly skilled to rig four booms with a double purchase (Figure 3-34). This method should not be used except in case of emergency.
b. Operators may use the method of rigging on a double-rigged hatch to handle loads up to the combined safe working load of two booms, provided the safe working load of two parts of the cargo runner equals or exceeds the combined safe working load of two booms. To lift a load of 9 long tons on a double-rigged hatch using the block-in-bight method, operators must use 7/8-inch cargo runners. The safe working load of two parts would be approximately 10 tons. It is also possible to handle a 9-ton lift on a double-rigged hatch using small cargo runners by doubling up all four booms. Operators should use the following method:
(1) Place four 14-inch deep-throat blocks, two standard 14-inch blocks, two 1-inch wire rope slings, and four shackles, 1 1/4-inch or larger, on the deck.
(2) Insert the 1-inch wire rope slings through the standard 14-inch blocks and shackle eyes to the bottom of 14-inch deep-throat blocks.
(3) Lower the aft booms, lead the cargo runners through 14-inch deep-throat blocks, and attach them to the head of the booms (as described earlier). Then raise the aft booms.
(4) Lower the forward boom and repeat the previous step.
NOTE: Two winch operators are now required.
3-20. HAGGLUNDS CRANE. The electric-hydraulic (el-hydr) Hagglunds twin crane consists of two single cranes placed on a common platform. One of the single cranes in each twin crane set is the master and the other is the slave crane. Each single crane is dimensioned according to its specification and has a slewing platform, jib, pulley block (fastened to the column mast), hoist rope with load hook, driver's cabin with control panel, and pump unit. The pump unit is driven by an electric motor via a distribution gear to which the pumps (of hydraulic variable axial piston type) are directly connected. For each of the movements hoist, slewing, and luffing, there will be a hydraulic pump. Each of the pumps delivers oil to hydraulic motors (of radial piston type) fitted on the hoisting, winch, the luffing winch, and the slewing gear (see Figure 3-35).
a. Theory of Operation. The theory of operation for the Hagglunds crane is listed below.
(1) The Hagglunds crane can hoist, luff, and slew cargo within its rated load capacities and physical operation parameter in the single or twin mode. The Hagglunds crane has control features allowing single mode operation from one cab (master cab only). Twin cranes are used for teamed operation with heavy lifts. During a single mode operation, each crane is independently operated. The Hagglunds crane is capable of auto spotting during crane operation (see Figure 3-36).
Figure 3-36. Various crane layouts for operations
(2) For twin operation purposes, each twin crane is delivered with a 60-ton (32-ton) traverse. For container operations the cranes are fully quipped with automatic spotting devices and spreader control equipment.
b. Craneman's Cab. The craneman's cab affords an excellent all-around view of the entire work area and ready access to the two control levers. One lever controls the hoisting winch, the other controls the luffing and slewing movements. The cab also contains control panels with various switches, control buttons, and signal lamps.
c. Jib/Boom. The jib is made up of two box girders, jointed by transverse tubular steel struts. The foot of the jib mounts on two trunnion journals at sides of the crane house skirt. On the inside of one of the longitudinal members is a dial with a balanced pointer that continually indicates the actual jib point radius in meters. A mercury lamp floodlight is also mounted on the jib. The jibs are 81 feet in length.
d. Crane House. The crane house encloses all mechanical and hydraulic machinery and associated electric equipment. The crane house protects this machinery and equipment against rain, sleet, and waves breaking over the ship. Two large-size doors in the crane house give access to the enclosed machinery for ease of inspection and maintenance.
e. Emergency Shutdown Switches. The Hagglunds crane has four emergency shutdown switches. One switch is located at the base of the crane house to shut down both cranes, one is located in the center of the engine room, and one each is located in the master crane engine room and the slave crane engine room.
f. Single/Twin Platform. A Hagglunds hydraulic twin crane set consists of two single cranes mounted on a common platform. The cranes may be operated independently or interconnected for twin operation. When operated independently, these cranes function the same as ordinary angle cranes.
g. Hoisting/Luffing Winch. The hoisting and luffing winch are mounted on the base of the crosstree. The drum and hydraulic motors are flange-connected and equipped with spring-loaded band brakes (hydraulic lifted, which means if power or pressure failure occurs the drum will stop). The drum is grooved for accepting the wire and dimensioned for having only one layer of wire. A sensing device will stop hoisting when wire tends to form a second layer; also the sensing device for an empty drum will stop when two turns are left on the drum.
h. Slewing Lock. The slewing locks (Figure 3-37) are located on the platform of each crane. The purpose of the slewing lock is to lock or unlock the platform so that the crane can operate in the single or twin mode.
i. Single Mode Operation. Each crane (master/slave) can be operated in a single configuration by unclamping the slewing locks and making arrangements for single operation. In the single mode, each crane can lift a maximum of 35 long tons at a 105-foot radius and 50 long tons at an 85-foot radius.
Figure 3-37. Slewing locks
- Shackle the ring of eyes of the lifting sling to a short wire bridle that has eyes at each end. Place the two eyes of the bridle over the two horns of the cane hook.
- Use 2 two-legged slings per lift, and place the rings of each sling over separate horns of the hook.
j. Twin Mode Operation. The Hagglunds crane can be operated in the twin mode and lift a maximum of 200 long tons at an 85-foot radius and 70 long tons at 105 feet. To operate in the twin mode, the selector switch in the master crane must be placed in twin position and the slewing platforms must be locked. To operate in the twin mode, only one operator is needed.
k. Rider Block Assembly. The rider block frame is a fabricated steel structure that contains a wire rope sheave with a lifting capacity of 20 tons. The rider block "rides" on the main hoist wire rope falls and allows positioning of the load and prevents excessive swaying.
l. Equalizing Bar. The equalizing bar is a fabricated steel beam containing a single swivel hook. The bar is attached to the rider block assembly of each crane for load equalization in the twin mode. The bar allows positioning of the load and prevents excessive swaying.
m. Sling and Bridle Rigging. The crane blocks are fitted with "ram's horn" type double hooks. Two methods of attaching ram's horn (Figure 3-38) are as follows:
n. Cargo Spotting Device. The cargo spotting device is used to position the load in a hold or on the quay. The cargo spotting device has a swivel housing with built-in machinery and one lifting eye in the upper part and one clevis in the lower part (Figure 3-39).
Figure 3-39. Cargo spotting device with container spreader
o. Container Spreader Device. The Hagglunds hydraulic spreader is designed to handle 20- and 40-foot containers according to ISO specifications. With this in mind, Hagglunds has designed a compact, low profile device providing mechanical connection of the spreader directly to a cargo spotting unit. The spreader is equipped with an automatic tilt corrector for longitudinal axis of the containers. The tilt corrector ensures that the container will be kept in the horizontal position. The spreader is controlled entirely from the driver's cab and is equipped with guide arms and remote-controlled retractable twist locks. This makes it necessary to station men on the dock or in the ship for location and securing.
(1) The spreader has a built-in, self-leveling device which can compensate for center of gravity displacement. Compensation is automatic but can be overridden by manual control. The spreader is remote-controlled from a panel located in the driver's cab. In case of cranes operated from a portable black box, the spreader controls will be in the same assembly.
(2) In order to avoid puncturing or damaging the container, the underside of the spreader is completely flush as the twist locks are retracted. This means that the spreader can be dropped onto the container top, eliminating counterswing. When the spreader is then lifted slightly, it can easily be positioned so that the retractable guides locate the corners of the container and adjust the relative position correctly.
3-21. HAND SIGNALS FOR HAGGLUNDS CRANE OPERATION. Crane hand signals are needed for a successful loading operation. Due to the size and depth of the ship, it is extremely important that hand signals are given correctly. When giving these signals, the signalman must be in clear view of the crane operator. The Hagglunds crane signals are shown in Figure 3-40.
Figure 3-40. Signals for Hagglunds crane operation
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