Injection mold cooling water leakage is a frequent occurrence, for many reasons, mainly in the following aspects:
The most occurs at the joint of the mold cooling water pipe. If water leakage is found, the sealing tape should be wound around the thread of the pipe joint and then tightened.
2, Due to long-term molding conditions, the waterproof ring inside the mold will be damaged, and the O-shaped waterproof rubber ring will easily harden and crack, resulting in water leakage. Some poorly installed waterproof rings can also cause seal failure. It is generally necessary to regularly check the installation position and sealing performance of the seal.
3, The hole wall of the cooling water hole is broken. This often happens when a new mold is tried. The wall thickness of the design is sufficient, but the hole wall is broken due to machining errors or post-processing. In most cases, leaking water holes can no longer be used.
4, Regularly repair the heating pipe and decompression pump and use. The heating tube is an effective heat transfer element and is very effective for core cooling of deep and deep structures. In the area where the cooling water is easy to pass, a one-way heating pipe is provided to reduce water leakage. In addition, the use of a vacuum pump to pump cooling water is also a method to prevent leakage of cooling water.
5, maintenance of the cooling water hole. It is easy to form scale in the cooling water hole, which hinders heat transfer. In severe cases, the water path is blocked and needs regular maintenance. For straight water holes, an iron bar that is 0.5 mm smaller than the diameter of the cooling water hole can be inserted and tapped with a hammer to remove scale and rust. For the cooling water pipe buried in the mold, the mold should be disassembled to remove rust.
After the inspection, the water leakage test should be carried out. The hand pressure pump is used to fill the water hole with water, and it is kept at a pressure of 2 MPa for 5 minutes. It is judged whether the water hole leaks by observing whether the water pressure is lowered. The water leakage can be blocked by mechanical fastening using elastic materials such as rubber and cork, and the room temperature curing type silica gel can be tried as a sealing material.