For large molds, due to the different filling rates in all directions, and the influence of the self-weight of the mold when the mold is installed, the moving and fixed molds are offset.

The lateral deflection force will be applied to the guide pillar during injection. When the mold is opened, the surface of the guide pillar will be rough and damaged. In severe cases, the guide pillar will be bent or cut off, and even the mold cannot be opened.

In order to solve the above problems, a high-strength positioning lock is needed on each of the four sides of the mold parting surface. The most convenient and effective way is to use a cylindrical lock. The verticality of the guide hole and the parting surface is very important. In the process, when the movable and fixed plates are clamped at the position, then use boring machine to ensure the holes concentricity. Minimize verticality error. In addition, the heat treatment hardness of the guide pillar and guide bush must meet the design requirements.