Abstract: The underground gas storage in salt caverns is an important gas storage and peak shaving facility. However,the saturated salt halides remaining in the salt caverns have a strong corrosive effect on metal materials. This requires good corrosion resistance of the inner wall of the injection and production pipe used for salt cavern gas storage. The linkage control equipment system for laser cladding on the inner wall of long steel pipes was developed and built. The quality and performance of the inner wall laser cladding nickel-based alloy pipes were inspected and tested. The test results show that the cladding layer has no defects such as crack and non-fusion;The thickness of the laser cladding layer is greater than 0.6 mm;The laser cladding layer has a good metallurgical bond with the pipe base material;The alloy composition of the cladding layer is consistent with that of Inconel 625 nickel-based alloy;According to the method of full immersion test for uniform corrosion in metal materials laboratory,the uniform corrosion rate of laser cladding alloys is 0.0018 mm/year without pitting,and all mechanical properties meet the index requirements.

Key words: compressed air energy storage, salt caverns, high-speed laser cladding, injection production pipes, laser cladding on inner wall of long pipes, corrosion resistance