... -1/2”, Casing coupling from 4-1/2” to 13-3/8”TYPE: NUE, EUE (tubing coupling), STC, LC, BTC ( ... Steel Tube Co., Ltd.)YingKou OuYang Metal Manufacturing Co., Ltd. is one leading manufacturer in the oil field .Our company is specializing in the process of oil casing ... oilfield and other oilfields. Until now, we have established a stable supply relationships with them. For overseas market, our products ...