Cooling water leakage of injection mold often occurs for many reasons, mainly in the following aspects. ① Most of them occur at the joint of mold cooling water pipe. If water leakage is found, a sealing tape should be wound on the thread of the pipe joint and then tightened. ② Under the condition of long-term molding, the waterproof ring in the mold will be damaged, and the O-shaped waterproof rubber ring is easy to harden and crack, resulting in water leakage. Poor installation of some waterproof rings will also cause seal failure. Generally, it is necessary to regularly check the installation position and sealing performance of the sealing ring.

③ the wall of the cooling water hole is damaged. This often happens when trying out new dies. The designed wall thickness is sufficient, but the hole wall is broken due to machining errors or post-machining. In most cases, the leaking water hole can't be used again. ④ Maintenance of cooling water holes. It is easy to scale in the cooling water hole, which hinders heat transfer, and when it is serious, it makes the waterway impassable and needs regular maintenance. For the straight water hole, a steel bar .5mm smaller than the diameter of the cooling water hole can be inserted and hammered to remove scale and rust. For the cooling water pipes buried in the mold, the mold should be decomposed to remove rust. After maintenance, a water leakage test should be carried out, and the water hole should be filled with water by a hand pump, and kept at a pressure of 2MPa for 5 minutes, and whether the water hole leaks can be judged by observing whether the water pressure decreases. The water leakage can be blocked by mechanical fastening with elastic materials such as rubber and cork, and the normal temperature curing silica gel can also be tried as the plugging material. ⑤ Regular maintenance and utilization of heating pipes and decompression pumps. Heating pipe is an effective heat transfer element, which is very effective for cooling the core of thin and deep structure. One-way heating pipes can reduce water leakage in the parts where cooling water is easy to pass. In addition, using decompression pump to suck cooling water is also a method to prevent cooling water from leaking.