The first thing to look at is the complexity of the structure of the mold. Generally speaking, it takes about a month to open a plastic mold. The time required for a mold with a complex process is more durable.
Usually, a plastic mold is opened, it is necessary to do a detailed review, and the mold can only be opened after the review is completed. A plastic mold is opened and it is required to test the mold for inspection.
What should I pay attention to in the production of plastic Molds?
Here are 19 items to share with you the needs of plastic mold making.
- The shrinkage coefficient of each material is different, and the plastic mold must have a reasonable shrinkage rate.
- The plastic mold must have sufficient rigidity, otherwise, it will be deformed when the mold is held under pressure, causing burrs.
- If the product is ejected while opening the mold, the ejector pin page of the injection molding machine can be set (but some injection molding machines do not have this function).
- Choose a reasonable demoulding method, choose a reasonable jack position and quantity to ensure that the product is not damaged during the jacking process.
- The cooling (water passage) in the plastic mold is related to the product size, shape, plastic properties, pressure holding time, and other factors.
- The plastic mold should choose a reasonable exhaust position and its volume control. Otherwise, it will cause dissatisfaction with plastic injection and product shortage.
- The fixing method of the plastic mold and the injection molding machine should be reasonable, reliable, and firm, and prevent accidents caused by the displacement of the mold when closing. And it is easy to disassemble.
- The plastic mold moves with the injection molding machine together with the moving mold part without the return spring. The mold thimble plate and the machine thimble bar are connected together.
- The injection molding channel should be selected reasonably so that the material can reach every place uniformly (the flow paths are equal), and there must be enough storage capacity to ensure that the plastic replenishes the plastic during the shrinking process.
- Post-processing of plastic mold materials is not required, because plastics are soft and do not require any special requirements such as hardness, and the heat treatment process may cause mold deformation.
- The roughness level of the plastic mold cavity should reach the mirror level, otherwise, the product will be difficult to demold, and the product will be damaged due to excessive force when the product is ejected. The roughness of the positioning pin, the clamping surface, and other parts are all stipulated by the standard.
- The wall thickness should be as uniform as possible, and the draft angle should be large enough.
- The transition part is gradually transitioned to a smooth transition to prevent sharp corners.
- Gate. The flow channel should be as wide and thick as possible, and the gate position should be set according to the shrinking and condensing process. If necessary, a cold material well should be added.
- The surface of the injection mold is smooth and the roughness is low (preferably 0.8)
- Exhaust holes and grooves must be sufficient to exhaust air and melt gas in a timely manner.
- In addition to PET, the wall thickness should not be too thin, generally not less than 1mm.
- The cooling (water passage) in the injection mold is related to the product size, shape, plastic properties, pressure holding time, and other factors.
- The fixing method of the injection mold and the injection molding machine should be reasonable, be firm and strong, and avoid the accident caused by the displacement when the mold is closed. And it must be easy to disassemble, and also, choose a reasonable demoulding method, choose a reasonable pin position and number, to ensure that the product is not damaged during the ejection process.