| 摘要 |
PURPOSE:To prevent corrosion by cooling water and prolong the lives of a mold base and a cooling box by forming protective metallic coating layers on the lower end surface of the mold base and that of the cooling box. CONSTITUTION:In the junction surface between a copper-made mold base 1 and a cooling box 3, an O ring 3 is fitted. On the internal surface of the mold base 1, a plating layer 4 is provided; the layer 4 consists of an Ni internal layer, a P intermediate layer, and a Cr surface layer. A protective metallic coating layer 9 covers the lower end surfaces 5 and 5' of the mold base 5 and cooling box 2. In coating the lowr end surface 5' of the cooling box 2, it is unnecessary to coat the entire surface all the time, and the coating of the part behind a spray nozzle 8 is not necessary. Thus, the corrosion of the cooling box 2 is effectively prevented as well as that of the mold base 1. |
