... , construction, engineering, power station, cylinder, automobile. Used in oil and gas industry, construction, engineering, power station, cylinder, automobile. Standard: GB/T3087,3639,5310 ... .6 √√√√√√√√√√√406.4 √√√√√√√√√√√457.2 √√√√√√√√√√508 √√√√√√√√√√558.9 √√√√√√√√√√609.6 √√√√√√√√√√ Seamless Steel Pipe