Different types of plastic molds, different types of molded plastics (the same type of mold), due to different starting and precision requirements, assembly methods are not the same. Therefore, the assembly drawing and part drawing should be carefully studied before assembly. The assembly basis is determined by understanding the function, characteristics, and technical requirements of each part. After careful assembly, the product's various quality indicators, including mold movement accuracy and other technical requirements during use, are achieved.

1, assembly benchmark

Assembly basis is the benchmark used to determine the relative position of a part or part in a product during assembly. It can be broadly divided into:

(1) The main working parts such as cores, cavities and inserts are used as reference parts for assembly;

(2) Use the guide bushing or the template side base of the mold as the mounting reference surface.

2, assembly accuracy

Assembly accuracy refers to geometric accuracy, machining accuracy, motion accuracy, etc. after assembly. The assembly accuracy of plastic molds includes:

(1) The mutual precision of each component, such as distance dimension accuracy, coaxiality, equality, verticality, etc.;

(2) Relative motion accuracy, such as transmission accuracy linear motion and rotary motion accuracy;

(3) Matching accuracy and contact accuracy, such as matching clearance, interference contact status, etc.;

(4) The wall thickness of the plastic molded part. When the new mold is made, the wall thickness of the formed part should be biased to the lower limit of the size.

3, the principle of repair:

(1) Repair the draft angle. In principle, the cavity should ensure that the large end size is within the tolerance range of the part. The core should ensure that the small end size is within the tolerance of the part size;

(2) The fillet radius at the corner, the cavity should be small, and the core should be too large;

(3) When the mold has both a horizontal parting surface and a vertical parting surface, the correction should be such that the horizontal parting surface is slightly left with a gap when the vertical parting surface is in contact, and the small molds need only be painted with red and then contact each other. Yes, the large mold gap is about 0.02mm;

(4) For molds that are clamped with a bevel, after the slope is tightly closed, a gap of 0.02-0.03 mm should be left at the parting surface;

(5) The arc of the repair surface should be smoothed to the straight line, the surface should not be dented, and the ridged line should be consistent with the mold opening direction.