... Donghai Steel Pipe Co., Ltd. name seamless steel pipe for oil fieldBrand namedonghai steel pipeStandardAPI 5CT ,API 5L,ASTM A53, ... -2006 Material St35.8, St44 ,St52, 20Mn2 ,10, 20,35,45, 16Mn,Q345,20G,20MnG, 25MnG,15CrMoG,12Cr1MoVG, ... -30days for an order less than 1000 tonsSurface treatmentBlack paint, yellow/transparent an-ti rust oil, galvanizedUsagePetroleum, chemical, power, gas, industrial ...