(1) The main oil casing pipe importing countries are: Germany, Japan, Romania, Czech Republic, Italy, United Kingdom, Austria, Switzerland, United States, Argentina, Singapore also have imports. The import standards mostly refer to the American Petroleum Institute standards API5A, 5AX, 5AC. Steel grades are H-40, J-55, N-80, P-110, C-75, C-95, etc. The specifications...
