... a new steel valve seat on the basis of original foundry material QZ1-QZ6ZBJ93002-87 Our company relying on military technology ... -Wuling Automobile Co., Ltd,Beijing Foton Automobile Co., Ltd., Mianyang Xinchen Co., Ltd, Xinguang huachen Co., Ltd,Yuchai Machine. Weichai Diesel engine Co., Ltd, Tianjing Perkins , Briggs & Stratton Co., Ltd and so ...