Refrigerated Cargo Ships / Reefers
Refrigerated cargo ships are basically fast general cargo ships with extensive refrigerated spaces for the transport of meat, fruit, and dairy products. They may several 'tween decks. Cargo may be carried frozen or chilled. Hold volume is less than an equivalent sized cargo ship because of the space taken by insulation-about 25 percent less for chilled cargo and about 35 percent less for frozen cargo. If all cargo spaces are refrigerated, the ship is called a fully refrigerated ship, or reefer. If only some of the holds are refrigerated, the ship is a partial reefer; the refrigerated holds are generally those closest to the machinery spaces.
Some sources report that the designation "AKF" is Auxiliary Cargo Float-On/Float-Off Ship, while others report the designation "AKF" for Refrigerated Cargo Ship.
Cargo volume is an important factor since refrigerated cargo has a fairly high stowage rate: chilled beef stows at about 127 cubic feet per ton, frozen beef at about 94 cubic feet, and bananas at about 157 cubic feet. Chilled beef is hung from hooks and chains, with approximately one foot clearance between the meat and the deck for air circulation; the effective KG of the hung meat is thus at the overhead of the storeroom, rather than near mid-height. Frozen meat is usually stacked; storage height is usually less than 20 feet to avoid crushing the lower tiers. Cargo spaces may be divided into bins for the stowage of fruit; permanent uprights, slotted to accept removable battens, are fitted at about 10 foot intervals.
Reefers are so called because they are refrigerated ships designed to carry frozen or chilled cargo, such as bananas, various types of fruit, orange concentrate, meat and fish. Since their cargo is perishable, these ships are designed to be fast, and often will have white painted hulls to reflect the suns heat, helping to keep the cargo cool. They are most notably used in the trade between Europe and the West Indies - it could be said that Reefers are the modern equivalent of the famous 'Banana Boat'.
Reefer ships are effectively large refrigerators, heavily insulated and shuttered with bright metal that prevents taint and is easy to clean. They are ships that tend to be divided into many more spaces than conventional dry cargo ships, with several decks and even locker spaces, so that different commodities can be separated and carried, if required, at different temperatures. Below the decks a reefer ship resembles a large modern warehouse, and cargo is usually carried and handled in palletized form, moved about on conveyors or by electric fork lift trucks. Some cargo, such as bananas, is often handled through doors in the ship's side. Cleanliness and the maintenance of optimum temperatures are the pre-requisites.
Modern refrigeration plant works with environmentally kind refrigerants, is largely automated. They can usually carry refrigerated containers on deck . A large reefer ship might typically offer about 500,000 cubic feet ( 14200 Cubic meters)of refrigerated space, and be capable of loading 250 containers on deck. Some Reefer ships carry as little as 90,000 cubic feet (about 2550 cubic meters). In simple terms a Reefer ship, depending on its size can accommodate the cargo of about 40 to 250 trucks.
Reefer ships operate seasonally, but because there is a heavy trade between the hemispheres, can remain active throughout the year. In recent years, too much new construction has led to over tonnage. The specialist Reefer ships, which are generally operated as tramps rather than in the liner trades, are seeing their cargo base increasingly attacked by large container ships, which are offering more slots for refrigerated boxes. Indeed the largest reefer capacity in a single ship is not on a "traditional" reefer, but aboard a large container ship.
Reefer containers are either fitted with their individual refrigeration units which can be plugged in to the ship's electrical power source. With the increase in exotic food cargoes, special containers have been devised that can tailor the internal atmosphere to the precise requirement of the foodstuffs.
The tentative U.S. standards for the Grades of dressed beef were formulated in 1916. They provided the basis of uniformly reporting the dressed beef markets according to grades, which work was inaugurated as a national service early in 1917. The grade specifications were improved from time to time as experience gained through their use indicated what changes were necessary.
The tentative standards, although designed primarily for meat market reporting purposes, were put to practical test in numerous ways. During World War I they were used in the selection of beef for the Army, Navy, and Allies. Later they were included in the specifications of the Emergency Fleet Corporation for the purchase of its beef supplies. Soon thereafter they were incorporated in the specifications of many commercial concerns, including steamship lines, restaurants, hotels, dining car services, and hospitals.
They were published first in mimeograph form in June 1923. After slight changes they were included in the Department Bulletin No. 1246 "Market Classes and Grades of Dressed Beef" which was published in August 1924. Public hearings were held at Portland, OR, Chicago, IL, and New York, NY, in 1925 to give producers, slaughterers, wholesale and retail meat dealers, agricultural college workers and others interested in the marketing of livestock and meat an opportunity to make suggestions for improving the standards. The sentiment registered at those meetings was overwhelmingly in favor of the grades as presented. The few suggestions and criticisms offered were carefully considered in subsequent revisions of the standards. The revised grade descriptions were promulgated by the Secretary of Agriculture, June 3, 1926, as the Official United States Standards for the Grades of Carcass Beef and published in Service and Regulatory Announcements No. 99 (B.A.E.). These standards provided the basis for grading when the voluntary beef grading and stamping service was begun in May 1927.
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