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BMP-40A Atomic Reactor, Submarine

Since the late 1950s, intensive research had been conducted at the research institutes and design bureaus of the Minsredmash and the Ministry of Industry and Industry on the development of a nuclear missile launcher for an automated high-speed small displacement submarine with a crew of up to 15-20 people (fighter boats of surface ships and nuclear submarines of a probable enemy), which received the project design index 705.

In the early 1960s, in connection with the creation and launch of combat patrols into the ocean of US submarine missile carriers, which were called “city killers” in the Western world (according to the type of target selection — their missiles were aimed at Soviet cities), a decision was made in the USSR on the creation of special anti-submarine submarines. One of the points of the program was the task to build a small high-speed automated boat - a submarine fighter, i.e. fighter of "city killers."

The idea of creating such a boat belonged to Academician A.P. Alexandrov and chief designer of the first domestic nuclear submarine, pr. 627 V.N. Peregudov. They were supported by D.F. Ustinov (at that time the chairman of the military-industrial complex under the Council of Ministers of the USSR) and a number of ministers who, in May 1960, sent a corresponding letter to the Central Committee of the CPSU. As a result, by a special resolution of the CPSU Central Committee in June 1960, this proposal and the direction of the relevant work were approved.

The design of the nuclear submarine of project 705 (Soviet code “Lira”) began after the decision of the Central Committee of the CPSU and the Council of Ministers of the USSR in the summer of 1960. The main task is to create a highly maneuverable, high-speed, small displacement of a submarine with a nuclear power plant, with a titanium hull, with a sharp reduction in numbers crew, with the introduction of new weapons and equipment.

Later, the initiative team of the IPPE and OKB Gidropress came up with the initiative to develop their own version of PPU with a liquid metal coolant for the nuclear submarines of project 705, which proposed a different circuit design solution for the PPU - in block design and with a symmetrical scheme (two loops instead of three), which simplified the composition installation and reduced the amount of installation work on the slipway. By the decision of the military-industrial complex commission in October 1962, this version of the control unit was legalized under the BM-40A index, and the project number 705K was assigned to the boats. The construction of the nuclear submarine of project 705K was entrusted to the Sevmash enterprise (Severodvinsk).

The most important element of the steam generating installation of the new boat was a lead-bismuth coolant reactor developed under the scientific supervision of the IPPE. Heavy biological protection and low steam parameters of nuclear power plants with a water-water reactor (for that period) led to a large specific gravity of the reactor installation. The new reactor with a liquid metal coolant made it possible to reduce the displacement, the diameter of the robust hull and the length of the submarine, and increase the speed of the underwater course. Due to this, the principal difference between the new steam generating unit was compactness, block layout, a high degree of automation and maneuverability, good economic and overall dimensions.

A special place in the development of reactors with lead-bismuth coolant was occupied by the problem of the technology of this coolant. This phrase refers to methods of monitoring and maintaining the required quality of the coolant and the purity of the primary circuit during the operation of the reactor installation. The importance of this problem was recognized after the accident at the K-27 boat in May 1968. Corresponding methods and devices for maintaining the quality of the coolant were developed when the construction of the planned series of submarines of projects 705 and 705K was completed.

Outline designs of both PPU (OK-550 and BM-40A) were approved in 1963, technical projects in 1965. However, due to the apparent advantage of BMP-40A PPU (approximately 100 tons), this project was revised and re-approved only in 1968. The thermal power of the reactors of both PPU (OK-550 and BM-40A) was the same - 155 MW, which provided a nuclear power of 40,000 hp. In the reactors, rod-type fuel elements with a diameter of 12 mm were used, assembled in fuel assemblies. Metallic beryllium was used as a neutron moderator in the reactor.

Project 705 and 705K submarines had record high underwater speed (more than 40 knots) and maneuverability, they successfully completed several long autonomous trips. It took them about 1 minute to accelerate to full speed, and it took 42 seconds to circulate with a 180° turn. For speed, the submarine of project 705 was even listed in the Guinness Book of Records.

At the same time, even with good PPU, the operation of the boats of projects 705 and 705K with LMT had certain difficulties, such as the difficulty of eliminating malfunctions due to the tightness of the reactor compartment, the need for an external energy source when being at the base with the reactor shut off, the need for regular regeneration of the coolant ... for these problems in the early 90s, when the submarine fleet began to decline, they began to be decommissioned. The K-705 submarines were decommissioned in 1990, and the 705K submarines in 1996.

The commanders and officers of submarines with reactor facilities developed at the IPPE gave a very high rating to the submarine itself and its nuclear power plant, calling it a “miracle boat” that was far ahead of its time.

Today it can be considered universally recognized that in the IPPE under the direction of A.I. Leypunsky laid the foundations for a new direction in nuclear energy, and a unique reactor technology was demonstrated on an industrial scale. This made it possible to ensure the compactness of the reactor installation, which is important when creating submarines of limited displacement, to ensure high maneuverability, and to increase the reliability and safety of the reactor installation.

A great contribution to the development of this direction was made by A.A. Bakulevsky, B.F. Gromov , K.I. Karikh, V.A. Kuznetsov, I.M. Kurbatov, V.A. Malykh , G.I. Marchuk , D.M. Ovechkin , Yu.I. Orlov, D.V. Pankratov, Yu.A. Prokhorov, V.N. Stepanov, V.I. Subbotin , G.I. Toshinsky, A.P. Trifonov, V.V. Chekunov and many others.

With the withdrawal of the last submarine from the Navy from the Navy, a certain stage in the development of ship nuclear energy was completed. The use of liquid metal coolant reactors in nuclear submarines has two opposing views. Some, and most of them, considered this a mistake due to the accident rate and low reliability of the equipment. Others pointed to the high combat qualities of the nuclear submarines: project 705 and 705K boats could successfully evade enemy torpedoes precisely at the expense of speed and maneuverability, short time to bring the reactor out of a subcritical state into energy mode, and ease of control.

These and other arguments prove the promise of this direction. In addition, over time, scientists and designers solved the problem of “freezing” and “thawing” the alloy in the installation, however, ships with liquid metal coolant are not currently being built.

The lead nuclear submarine of project 705K with BM-40A PPU, which received the K-123 code, was completed by mid-1977. In June, the Interagency Commission conducted comprehensive mooring tests of the nuclear power plant, in August-November 1977 the nuclear submarine underwent factory and state sea trials and was handed over to the fleet (the acceptance certificate was signed in December 1977). In total, until 1981 two more submarines of project 705K were built: K-432 and K-493.

In April 1982, during a cruise of the K-123 nuclear submarine, a PPU accident occurred - due to improper crew actions, the alloy was thrown into the compartment through the impulse pipe of the gas system. PPU had to be taken out of action and “frozen”. The subsequent revision of the PUF also revealed irreparable great corrosion damage to the steam generator pipe systems from the side of the secondary circuit, which required a complete replacement of the PPU compartment (there was a replacement BM-40A installation kit).

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Page last modified: 13-08-2019 10:24:45 ZULU