Shanghai Tianzuo Oil Equipment Grou is an internationalenterprise specialized in manufacturing and distributingprofessional petroleum equipments and accessories. Withheadquarter located in Shanghai and production based in Tianjin,the most important seamless carbon steel and alloy steel tubesdistribution center in China. Our annual output are over100,000MT, annual sales revenue 650 million. Complying withthe specifications GB, ASTM, ASME, API, JIS, DIN, and BS, and have obtained theAmerican Petroleum Institute&＃39;s certificate and API certificate for API 5CT, API 5Land API 5D, and our products has been exported to more then 56 countries in theworld