Installation method and precautions of large diameter welding ball valve and electric welding ball valve welding ball valve ,electric welding ball valve,jinketongli ball valve DESCRIPTION:HEBEI TONGLI AUTOMATIC CONTROL VALVE MANUFACTURING CO.,LTD.was founded in 1995 which headquarter is located in township of casting the fourth development zone of Botou city of Hebei province.The company is a professional manufacturer which can research, produce and sale. Meanwhile, we focus on researching, producing and saling of heating valves after nearly 20 years of development and innovation. The company can provide projects of designing, installating and adjusting of HVAC (heati