... for fluid transportStructure pipe10# 20# 45# 27SiMnASTM A53A,B16MnB,C,D,E> 20Cr 40Cr 20CrMo 30-35CrMo 42CrMo40Mn2 35Cr ... -100apply to oil, gas, water, oxygen transport in oil and gas industry ERW steel pipe20# Q195 Q215A,BQ235A,B Q345A,B,C,D,EGB ... to structure support, low pressure fluid transportSpiral steel pipe Q235A-B Q345A-ESY/T5037-2000219-2820*4-20apply to low pressure ...