Cangzhou Duda Pipe Fittings Co., Ltd locates in Yanshan County of Hebei Province , congregating of manufacture , sale and export of steel pipes and fittings . Nearby Tianjin and Beijing City , we are of convenient transportation . The factory covers about an area of 100,000 square meters , with the 30,000 square meters workshop . There we have a very strong staff team , over 500 employees , including 3 senior engineers , 12 engineers and 150 technicians . Our leading products are steel ...