Loosening Korea's three newest submarines is banned from navigation

According to South Korea's "Korean Daily" reported on the 18th, the Korean Navy's three new 214 (1800 tons) submarines were all ordered to suspend operations due to hull deficiencies early last year.

It is reported that the Korea Auditorate detected the issue in December last year. Song Yongxian, a member of the National Assembly, said that the 214-class submarine is required to withstand huge water pressure operations in the deep sea with a maximum depth of 400 meters. If the important part of the fixed screw is loose during navigation, it can easily cause major accidents. It is reported that the South Korean navy explained that the screws will be repaired whenever there is a problem, so the war will not be affected.

According to a survey conducted by the South Korean Navy, the first reason is that the product delivered by the manufacturer of the screw, South Korea W, did not meet the HDW company's design requirements for bite strength. The South Korean Navy and Hyundai Heavy Industries changed all the screws of the fixed deck according to HDW's specifications. However, the screws still appeared loose. HDW's technicians personally went to South Korea. From June last year to February of this year, another layer of steel plate was added inside the deck and fixed with supporting bolts.

Some officials revealed that during the period from 2006 to 2009, the 214-class submarine No. 1 Sun Yuanyi had more than 20 fixed-deck screws loosening six times during navigation. The No. 2 boat “Zheng Di” had also experienced loosening or breaking of screws in 2009 from 2009 to 2010. During the period from 2009 to 2010, the No. 3 boat “Ansonggen” had problems with three screws, two of which were loose and two were broken.

The reason is that the screws on the deck of the fixed bridge (projecting part above the hull of the submarine) are poorly engaged and the screws often loosen or break during navigation. The 214-class submarine was designed by the German HDW shipyard. The South Korean Navy’s main submarine was built by Hyundai Heavy Industries. The three ships built from 2007 to 2009 have all been listed as troops. It is currently planned to install six more.