Drill String Cross-over Sub uses AISI4145H chromium-molybdenum steel, execute API specification.We can produce the same-dia type, reducers type and L-type three types, the screw can be cold thread rolling, copper or phosphate treatment.
KUNFENG will take strict quality supervision of steel products, provide qualified API 5L X42(L290)PSL1steel plate with the best quality and reasonable price for our customers.