Seamless steel pipe Size:OD:20. ... ,45# ,Q345, Q235 , standard:API,ASTM,GB Seamless steel pipe1Type: seamless pipes, welded pipes, welded pipes, rectangular pipes, square ... pipes, polished pipes, seamless tubes.2 Process methods: cold draw and cold ... , Q235,Q345 ,etc.6 Applications: Chemical Industry, Petroleum, Medicine, Food, Machinery, Construction, etc. seamless steel pipe