These engineers who have changed the appearance of China have a "big iron ox" that can dive into the seabed of the South China Sea. It is 7.6 meters tall, has a waist circumference of 10 meters, and weighs 12 tons. Don't be fooled by its large arms and round waist, it has extraordinary skills - landing on the seabed of the South China Sea at a depth of 2000 meters, successfully driving the drill bit into a depth of 231 meters, setting a world record in one fell swoop! This "Big Iron Bull" is called "Manatee II", and the chief scientist who created it is Professor Wan Buyan from Hunan University of Science and Technology. "Only by holding the 'diamond' in hand can one not be constrained by others." From refusing high paying jobs abroad and resolutely returning to China, to leading a team to independently develop key technologies from scratch, Wan Buyan's belief has always been simple and firm. "Drilling over 200 meters in the deep sea seabed means that China theoretically has the ability to fully cover marine mineral resources for exploration." This is the deepest gift that Wan Buyan has given to our country... To tackle the most difficult situation - "the more difficulties we encounter, the more we need to 'drill through' all difficulties." Time has been set back to April 7, 2021. In the water! Lower it down! Get in! As drilling deeper and deeper, the numbers on the display screen kept jumping, from 0 to 3, 3 to 6, 6 to 9... until 231 meters! Wan Buyan in the control room breathed a long sigh of relief, his eyes turning red. "Great, we succeeded!" cheers erupted from the crowd. At a depth of 2000 meters underwater in the South China Sea, successfully drilled 231 meters and obtained natural gas hydrates (combustible ice) while maintaining pressure. "Hainiu II" achieved this! This not only fills the gap in China's deep-sea drilling rig equipment with a depth greater than 100 meters and pressure holding and core taking functions, but also sets a new record for the world's deep-sea drilling rig depth. How can drilling machines withstand high pressure in the vast deep sea? How to safely put it down and retrieve it? How to supply power, communicate, and operate? How to ensure the accuracy and reliability of core sampling... Speaking of that unforgettable experience, Wan Buyan deeply felt that there is nothing that cannot be solved by hard work. The seabed terrain is complex and the environment is diverse. Conducting exploration of marine mineral resources and seabed engineering geological exploration cannot be separated from deep-sea drilling rig equipment. "It can be said that the development level of deep-sea drilling equipment directly determines the breadth, depth, and accuracy of deep-sea mineral resource exploration and development," said Wan Buyan. The "Manatee II" may seem like a behemoth, but when it reaches the seabed, it is as flexible as a loach, easy to operate, multifunctional, efficient, and low-cost. It has created a unique principle, technology, and process for sealing and pressure maintaining the entire length of the rock core tube, resulting in a combustible ice preservation rate of over 80%, leading relevant foreign technologies. "After years of struggling at sea, the most fearless thing is difficulty. The more difficulties we encounter, the more we must 'drill through' all difficulties," said Wan Buyan. During a sea trial, the supporting winch system of "Hainiu II" malfunctioned. The drilling rig is suspended 1000 meters underwater and cannot be retracted or lowered. The team urgently contacted the Danish manufacturer and sought help from domestic agents, but the response they received was "powerless.". "We have experienced many storms and waves, and we must not be intimidated by this difficulty. We will fix it ourselves!" Wan Buyan led the team members to try various methods, and finally decided to build a temporary hydraulic system. After nearly 3 years