Beijing TOPENSEA International Trade Co., Ltd. covers 86,580 square meters and has more than 600 employees, of which there are about 100 technical staff. With more than 30 sets of high-precision equipment in more than 80 sets of machines and monitoring equipments, the annual production capacity of our company reach 300,000 metric tons and the output value is up to RMB1.8 billion. Main products of our company include structural pipe, fluid pipe, petroleum casing pipe, oil pipe, line pipe, middle and low-pressure boiler tube, high-pressure boiler tube, hydrostatic pressure supporting tube,...