Among several main electroplating processes, chromium plating process is wear-resistant and low-cost, but it has serious environmental pollution and is not resistant to chloride ion corrosion. Electroless nickel-phosphorus plating process is corrosion-resistant but not wear-resistant, with high cost; Thermal spraying technology has good technical indexes, but the production cost is high, so it is difficult to popularize it on a large scale.
According to Professor He, a famous young chemical expert in China, a postdoctoral fellow at the University of California and a doctoral supervisor at Hunan University, "The research on the failure of parts caused by wear and corrosion shows that most of these failures occur on the surface of materials. Using surface engineering technology to treat the surface of materials to improve the surface properties of materials will effectively extend the service life of parts. Therefore, surface engineering plays an important role in the petroleum and petrochemical industry. "
"From the current point of view, only the technical performance of tungsten alloy electroplating has been greatly improved, and the hardness is equivalent to wear resistance and chromium plating, but it is acid and alkali resistant and has low production cost. Moreover, the electroplating solution can be prepared according to the specific operating conditions of the oil well, and the corresponding electroplating process can be implemented to meet its operating requirements. Now in the same environment, the service life of equipment for electroplating tungsten alloy is several times higher. " Professor He explained, "The reason why the electroplating performance of tungsten alloy is so superior is that the coating obtained by electroplating tungsten alloy is a new alloy material with amorphous structure. After different heat treatment processes, it can be transformed into amorphous mixed nanocrystals or nanocrystalline structure. The alloy has good wear resistance, acid resistance, alkali resistance, salt spray resistance and excellent high temperature oxidation resistance, which is very good with the base material.
Tungsten alloy electroplating technology has solved the two major problems of corrosion and wear in one fell swoop. According to statistics, there are more than 3 million tons of oil well pipes in China every year, and almost all high-end oil well pipes with high technology content and high added value, such as H2S-resistant and Cl- resistant oil pipes, are imported, and 600,000 tons of oil pipes are imported every year, worth more than 30 billion yuan. This achievement has been authorized by 8 patents, won the first prize of National Machinery Industry Science and Technology Award, and won the national key new product certificate. What makes Professor He even more happy is that the State Environmental Protection Administration has listed this technology as a key practical technology for national environmental protection (Class A) and an environmental protection technology encouraged by the state for resource conservation and comprehensive utilization.
The application of tungsten alloy electroplating technology in petroleum machinery industry can not only solve the pollution problem caused by chromium plating, but also improve the performance of various key parts of China petroleum machinery manufacturing industry, bring changes to the whole petroleum machinery manufacturing industry and promote the overall upgrading of the industrial chain. In particular, anti-corrosion and sulfur-resistant booms and sulfur-resistant drill pipes are suitable for H2S content greater than or equal to 1.5 million PPM. The extremely corrosive environment with CL- content 1.50g/L has enabled China to reach the international leading level in this industry, and solved the current situation that China's high-end drilling and production equipment depends on imports.