1. steel pipe factory 2.ISO 9001 standards 3.min order 1 ... q235 etc material 5.used for gas oil etc precision steel pipe factoryISO9001 standardMaterial: Q 195,Q235,2#,45#,45mn 65mn ... components, oil cylinder, boiler equipment, medical equipment, fitness equipment, etc. steel pipe production linessteel pipe factory photossteel pipe stock productsteel pipe ...