The latest Russian nuclear submarines of projects 955A (codename Borei-A) and 885M (codename Yasen-M) will be practically undetectable for hydro-acoustic stations which are the main means to expose a submarine. The advantage will be provided by the latest noiseless domestically produced leak-proof pumps. Previously all Soviet and Russian-made submarines were equipped with pumps produced by the Gidrotekhnika scientific and technical center in Moldavia, the Izvestia daily reported.
The K-535 Yuriy Dolgorukiy, first Project 955 Borey-class SSBN
Each submarine has ten pumps which circulate liquid in the reactor, ensure submersion and surfacing, fill torpedo launches with water before engagement, cool the systems and equipment of the submarine. However their noisy operation is the main revealing problem of a nuclear submarine as hydro-acoustic stations of the adversary can hear it.
The unique Russian pumps were designed and are serially produced by the Blade Hydraulic Machines (LGM) enterprise. The Main Navy command told Izvestia the new sealless leak-proof electric pumps passed a full test trial cycle and were introduced into the technical projects of perspective nuclear submarines and those under construction.
The enterprise confirmed the creation of the pumps had been completed and supplies to the customer began. "The items and the production line have been fully created at the expense of the enterprise," LGM Executive Director Roman Pykhtin told Izvestia.
Russian Navy First Project 885 Yasen-class Submarine Severodvinsk (K-560) underway
"All pumps meet category 4 requirements for vibrating hydraulic equipment. It is the top product category. A few companies produce such units in the world. Their characteristics are super secret as they determine the physical portrait of each specific submarine. If they are known it is easy to detect it on the background of natural ocean noise," he said.
The Gidrotekhnika in Chisinau supplied pumps for the Soviet and Russian Navy since 1962. Until recently the Moldavian products were purchased for all Russian warships under construction. The LGM pumps are a fully Russian product. They have a simple construction, small size and upgraded vibration and noise insulation. A pump operating at full swing can keep on its cap a five-ruble coin standing on its edge.
Expert Vladimir Shcherbakov told Izvestia the decreased noise of submarine systems and mechanisms is one of the major problems. "The noisiness of a submarine is caused by numerous factors. It is mostly the operation of the main power plant - the nuclear reactor, pumps, diesel engines, shafts, screws, water jets. In case of propellers and water jets the noise is decreased by the upgrade of the mechanisms. It is possible to decrease the noise of an operating diesel engine or auxiliary mechanisms by suspensions and rubber mats on which they are placed. It is more difficult with the reactor as it could not be installed on a vibration platform and covered by rugs. It is possible to decrease the noise by upgrading its pumps. The noise produced by constantly circulating liquid is the loudest on a nuclear submarine," he said.
At present nuclear submarines of projects 995A (five units) and 885M (6 boats) are being built for the Russian Navy. Only domestically-made equipment is used in construction. In future modular fifth-generation Husky-class submarines have to be laid and built with exclusively Russian-made systems and mechanisms, Izvestia said.
https://navyrecognition.com/index.php/news/defence-news/2017/august-2017-navy-naval-forces-defense-industry-technology-maritime-security-global-news/5481-russian-project-955a-and-885m-submarines-to-get-noiseless-leak-proof-pumps.html