Tianjin Jinggong Petroleum Pipe Fittings Co., Ltd., located in Tianjin City, is an experienced joint-venture petroleum pipe and fitting manufacturer. We enjoy convenient transportation access and lower material cost. We have 10 modes of tubing couplings and 37 modes of casing couplings, which have 6 steel levels. Main kinds of thread are long round thread casing (LC), short round thread casing (STC) and buttress thread casing (BC). Special-bevel couplings have non-upset tubing (NU)) and extend-upset tubing EU. NU has a mode of special-clearance coupling. EU has two modes of special -clearance...