... firms namely Qingdao Wefsun Metal Material Co., Ltd, Qingdao Sanshan Metal Material Co., Ltd, Qingdao Kaimingyuan International Trading Co., Ltd, Qingdao Wofeiteng Steel Pipe Co., Ltd and Qingdao Woming Steel Pipe Co.,Ltd,were established ... collection of manufacture, trade, processing and distribution for one integrated company, which is the most resourceful company in Qingdao. Our company trades ...