The main pipeline for connecting tubes and maintain sealing performance, easy to replace certain pipeline to facilitate open Check lines, the ease of closing certain pipeline. Huff section: straight for Gas (socket) parts occurs trachoma, crack, fracture repair. Mainly used in drinking water and the temperature is not high 135 ℃ of hot water, boiler heat exchanger pipe network, drinking water delivery, the higher requirements of high decorative cold water, heating, oil pipeline network and water quality requirements of food, medicine , and other chemical and electronics industry, and so on low pressure fluid pipeline network industries