... materials are supplied by Chinalco Luoyang Copper Co., Ltd. that is the best copper supplier in China,all the copper purity is 99 ... Industries (CFHI),China National Erzhong Group Co.,Dongbei Special Steel Group Co., Ltd.,Daye Special Steel Co.,Ltd.,Xining Special Steel Co., Ltd.,Tiangong International Co., Ltd., etc.,and Tiangong International Co., Ltd. always ...