A task book for the maintenance and modification of minesweepers signed by the N fleet was sent to the Endeavor factory a week after Dong Yimin investigated the Endeavor Factory.

The converted target ship is a Type 389 minesweeper with a board number of 6610, built in 1963, with a standard displacement of 520 tons and a full load displacement of 590 tons.

This type of ship is the first generation of minesweepers copied by China on the basis of the Soviet Union's Type 254M (also known as T43 class) minesweepers, and the first eight ships were assembled in China by the Soviet Union in accordance with the technical drawings and technical materials provided by the Soviet Union in accordance with the Sino-Soviet "June Fourth Agreement".

Project 389 is the 8th of these.

However, unlike the previous ships, the No. 389 ship did not blindly copy the Soviet 254M prototype, but made improvements according to the actual situation in China, such as adding a refrigeration system, comprehensively revising the ventilation system, canceling the boiler and heating system, replacing the air-conditioning system, and increasing the power of the moored diesel engine generator unit.

At the same time, it also strengthened its armament, the most notable of which was the change from the original twin-mounted 37mm naval gun to the more powerful 85mm naval gun, and the change of the original manual lifting machine to an electric chain lifting machine, thus increasing the firepower intensity of a single ship.

The main reason for the improvement of these equipment was to adapt to the operational environment of the N Fleet, and as for the effect, the Battle of the Paracels with South Vietnam in 1974 speaks for itself.

During the current service, the No. 389 ships of the N Fleet and the 396 ships of the same type formed a blocking formation, and a naval battle broke out with the South Vietnamese Navy's "Nu Tao" and "Li Changjie" in the northwest sea of Quang Kim Island.

After four hours of fierce fighting, the South Vietnamese Navy's escort gunboat "Nu Tao" was sunk and the destroyer "Li Changjie" was severely damaged, while the Chinese side paid the price of serious damage to ship No. 389 and ship 396 to minor injuries.

From this, we can see the excellent performance of the Project 6610 minesweeper, which has been specially improved.

However, the victory in the Battle of Xisha not only allowed the No. 389 ship to win the title of "Meritorious Ship", but also greatly reduced its performance, after all, it suffered heavy losses during the battle and was dragged by friendly ships before reluctantly returning to port.

Although the combat capability was later restored after repairs, the chronic diseases left on the battlefield were not completely eliminated, and more than ten years of service career also allowed the No. 389 ship to enter the middle and late stages of the ship's life.

Therefore, the 389th ship is like a wounded veteran, although it can still exert its residual heat, but it can no longer be the main force in the N fleet.

In the eighties, the state of the 389 ship became even worse, although the basic navigation ability was not a problem, but the nearly twenty years of age still made the N fleet use this meritorious ship as a second-tier ship, because of this, the 389 ship left the port very little, and therefore the technical state became very unstable.

The N fleet handed over such an old ship that was close to retirement to the Endeavor Factory for refit, in fact, it was also very helpless, they wanted to take other ships over for refit, but under the eyes of the Soviet Union and Vietnam, those ships in good condition could not move at all.

So they picked and chosen, and only the 389 ship had the potential to be refitted, and it would not weaken the main force of the N fleet, and the N fleet looked at it horizontally and vertically, so it sent the 389 ship to the slipway of the Endeavor Factory.

However, the decision of the N fleet made it difficult for Endeavour, and except for the two Soviet-original D-80 1100 horsepower diesel engines on the No. 389 ship, which were still in good condition, the other equipment was more or less damaged and malfunctioned.

For example, the power supply unit, not only the rated power is seriously inconsistent with the actual power, but the noise of operation is also very large, this is still a low-load operation, if it is running at full load, you can hear the roar of the ship from afar.

So much so that when the No. 389 ship went to sea, it did not dare to start the power supply unit, and could only bring a few sets of batteries as a backup power supply, but there was no way, the noise was too loud, and the officers and men on board could not stand it at all.

There are also two three-bladed propellers, because the imitation of the Soviet 254M minesweeper was improved by the Soviet Union according to the German minesweeper technology during World War II, so its technology stayed at the level of the mid-40s of the 20th century.

At that time, neither hydroacoustics nor hydrodynamics were very developed, so the configuration of the propellers also appeared very rough, and the overall technical level of the 389 ship was not substantially improved because it was an imitation of the Soviet minesweeper.

Therefore, the cavitation phenomenon and cavitation erosion of the propeller configured are very serious, especially the cavitation erosion, which has caused obvious pits of different sizes on the leaf surface of the two propellers of the No. 389 ship, which causes the No. 389 ship not only to make huge underwater noise, but also to cause the hull to vibrate violently from time to time.

As for cable damage, instrument failure and other minor problems, there are countless problems.

However, this is not the main reason for the headache of Endeavor Factory, no matter how bad the condition of the ship is, no matter how difficult the maintenance is, as long as there is enough time and materials, Endeavor Factory can repair it by gritting its teeth.

But the problem is that the N Fleet only gave Endeavor two and a half months to let the 389 ship, which was in a very poor state, return to the N Fleet as the capital ship.

Seeing this time limit, the factory director Jiao Dalin and the secretary Shen Damin almost didn't scold their mother on the spot.

That's right, two and a half months Endeavor Factory can build an inland river cruise ship, but it is only a civilian ship with very low technical standards, but the No. 389 ship is a military ship, even if it has been in service for 20 years, and the state is extremely poor, but a military ship is a military ship, and the standards applied and the technical level used are not at all comparable to civilian ships.

In other words, Endeavour can build a cruise ship in two and a half months, but it may not be able to repair a warship in the same amount of time.

What's more, the N fleet not only asked Endeavor to repair the No. 389 ship, but also required Endeavor to use its own noise reduction and shock absorption technology to make targeted improvements to the No. 389 ship.

Combined with the maintenance and improvement, combined with the displacement of more than 500 tons of the No. 389 ship, the entire project volume is larger than the construction of two cruise ships, and how can it be completed in two and a half months?

Therefore, Jiao Dalin and Shen Damin immediately poured bitter water like Zhang Bing, commander of the Kandong Marine Police District, and Lu Bin, chief of staff, who came to inspect, hoping that these two could react to the N fleet and see if they could delay the time for another two months.

Zhang Bing and Lu Bin also felt that the time of the N fleet was too stuck, so they reported the appeal of the Endeavor Factory, and the N fleet replied quickly, just one sentence: "The fleet is urgent, and there are no conditions!"

When it came to this, Jiao Dalin had to hold back even if he had a stomach full of bitterness, because he knew very well the weight of the fleet's urgency, and he also understood what it meant to Endeavor Factory to complete the maintenance and modification task of the No. 389 ship with quality and quantity, so he recruited Meng Jianye, who was in charge of technology, to the office overnight, and the two talked for three hours.

Meng Jianye finally came to the conclusion that as long as the scheduling is reasonable, the materials are sufficient, and the help of the 600-ton floating dock professional platform, it is still possible for the Endeavor Factory to win the maintenance and modification task of the No. 389 ship in two and a half months.

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