Xia Xiaojian

During the 13th Five-Year Plan period， in order to implement the maritime power strategy， China launched the ocean survey core equipment “Da Yang Hao” and other engineering projects， CSSC Huangpu Wenchong Shipbuilding Co.， Ltd. was selected as the “Da Yang Hao” construction unit.This is the first time that the company has undertaken the task of building a modern scientific research vessel.

China first ship to adopt the world's most advanced “integration scheme of variable speed diesel generator -- BPC DC busbar electric propulsion system and double straight blade propeller”， the Underwater Noise 3+1 additional symbol issued by CCS for the first time， double flipper and air guide sleeve sonar cabin，and more than 70 kinds of international cutting-edge marine survey equipment...“Da Yang Hao” fills in many gaps in the construction of scientific research ship in China， which means that the construction of “Da Yang Hao” is by no means easy. Huangpu Wenchong and all parties involved in the construction are united， gather wisdom and work together to solve key problems， the vast number of participants carry forward the tenacious military industry style of daring to fight hard battles and being capable to win the battle， experience 667 struggling days and nights from August 30， 2017 for kickoff to June 28， 2019 when the completion agreement was signed， successfully fulfilling the solemn promise of building a fine scientific research ship.

“Da Yang Hao” heart is made up of four sets of variable speed diesel generators， which are the main source of vibration noise for the whole ship. The four generators are installed on an 8m ×6m pedestal through shock absorbers. In order to ensure that the compression error of each of 32 shock absorbers does not exceed 1 mm， Cheng Kun， an experienced loading operator， puts forward the method of combining ordinary milling machine with laser tracker to make the machining flatness of the base not more than 0.5mm/m. But this is not enough. How to minimize the vibration and noise of the generator is the key for “Da Yang Hao” to obtain underwater radiation noise and comfort symbol， which allows designers to scratch their heads. In the end， the company creatively adopted double-layer floating raft technology， and under the combined action of multi-layer shock absorbers and blimps， the tsundere engine was finally“tamed”.

“Da Yang Hao” cabin is 17 meters long and 13.55 meters wide. Aside from the generator sets， 1262 pipes should be installed. In order to reduce vibration and noise， the gap between these pipes must exceed 20mm. Wu Jian， from the loading operation area， climbed all over the cabin with steel ruler and feeler gauge，sometimes even stuck by pipe， and was only able to get out with the help of his colleagues. Thanks to the joint efforts of technical and construction personnel，the “Da Yang Hao” cabin became the quietest cabin that the builders had ever heard. Lu Xiaoko， the general craftsman of the ship， said proudly， “When moored，you can hardly hear any noise in the cabin except the fan， it is definitely one of the quietest cabins on board a ship.”

“Da Yang Hao” has a large number of advanced， cutting-edge equipment which participants have never even heard of before. In order to be independent and controllable， all professional supervisors， debugging personnel are still buried in referring to all kinds of information after work of the equipment service provider， tirelessly studying the principles and technology，continuing to break with convention and solve difficult problems with the hardworking wisdom， one after another letting the equipment service provider sincerely convinced， so that the “Da Yang Hao”really won credits.

Inaddition to the main power system， the installation and commissioning of the scientific research system is also the key to the construction of “Da Yang Hao”. Under the condition of late arrival of scientific research equipment， tight project cycle and high installation requirements， the participants innovate the process and work hard to complete the installation of scientific research equipment successfully. In the construction of multi-beam horizontal pedestal， the ship loading operation area processes first and then positions， resulting in more than 10 days saving compared with the plan. In the installation of the seismic air pressure regulator， the construction staff work 24 hours and change shifts a week in a row.Due to the lag of delivery period， 6 sets of 17 scientific research winch equipment can only permit entrance by opening the process hole. Crane masters perform“stunt”， moving equipment with chain block and iron chains one by one onto board. In the tense construction， the participants bear in mind the requirements of building a “fine scientific research ship” and do a good job of equipment protection. None of the equipment in the whole ship is damaged or quality problem is caused by Huangpu Wenchong.

In order to improve the adaptability of the work environment of the scientific survey equipment and the comfort of the crew， Huangpu Wenchong carefully constructed， and the unique construction characteristics were embodied everywhere.Because the straight blade paddle device purchased by the “Da Yang Hao”does not meet the design requirement of ultra-low underwater noise requirements，in order to finally meet the design requirements， in addition to the cabin vibration reduction， the company also takes various measures such as installation of shock absorber， damper plate， fiber wall， vibration damping pipe code， flexible hose， etc. to make the “Da Yang Hao”meet the highest standards of C3 and V3 of China Classification Society in terms of noise and vibration.

The built-in design of the “Da Yang Hao” is operated by Tsinghua Academy of Fine Arts， which is famous in China. How to change the artist's beautiful image from blueprint to reality can best reflect Huangpu Wenchong's ingenuity and construction level. Before the construction of the ship， the project team built the cabin model room in proportion to 1:1， all the arrangements，facilities and homes were designed according to ergonomic principles; the conference room and restaurant adopted mobile separation， some furniture could be split and combined to meet the needs of different scenes; the apartment fourperson suite design was adopted， and two indoor and outdoor leisure areas were set up in the public area， which expanded the social space of scientists.Different decks use different main colors of decoration. The illuminance and color temperature of lighting in working area and living area are also different， the interior decoration of the whole ship is beautiful， practical and warm; the entrance guard of important cabin adopts face recognition， and the cabin adopts intelligent door lock; the working wooden deck of stern is equipped with container interface and anchor bolts， which can expand the function of scientific research in a modularization manner.

The Da Yang Hao's builders built fine ships for the country one after another and created a gold standard for Huangpu Wenchong: “The quality is excellent， reliable and serves the purpose， and the guarantee is in place”.It is believed that with the Da Yang Hao as a new starting point， Huangpu Wenchong will keep in mind the initial intention and the mission of “serving the country with military industry” and“building an ocean power”， and write a more wonderful chapter for Chinese marine cause.