... dump valves. Parameters Technical support Shanghai Zhengyuan Powder R&D Co., Ltd.Add:No.533, Yuanzhong Road, Industrial Park of Nanhui District ... )21-68015751 / 68015651 Fax:(086)21-68015117Weifang Zhengyuan Powder Engineering Equipment Co., Ltd.Add:No.169,Yuqing Street,Weifang,Shandong,ChinaTel:(086)536 ...