/How to design and make molds for plastic crates

How to design and make molds for plastic crates

Mold design requirements, characteristics for production of plastic crate

Mold plastic parts used in the production of plastic crate belongs to medium and large plastic parts. Plastic crate mould of various specifications generally have many similarities in their structure among home appliance mold, which is determined by similar appearance of designed plastic crate.

When designing crate mould, flow analysis software can be used for calculation and analysis to improve success probability of mold design and quality of plastic moulds. If hot runner technology is adopted, mold plastic part structure can be optimized, molding cycle can be shortened, and advanced mechanical ejection mode can be adopted in design and processing, which can improve reliability of mold plastic part movement.

Quality of plastic crate mould has a very large impact on quality of box products. When designing and processing an ideal quality and reliable plastic crate mould, mold and process should have following requirements:

  1. Weight and volume of designed mold plastic parts are required. In order to make mold small in weight and volume, it is only one-third of volume of mold using ordinary flow path and mechanical lateral parting structure.
  2. Requirements in terms of structure and operation. Plastic crate mould structure should be compact, and operation requirements should be high. If it is a lateral split structure, type of reset time should be flexible.
  3. It can reduce amount of raw materials, improve quality of raw materials, and improve utilization rate of materials.
  4. Processing time requirements. It can reduce cooling time of plastic crate to shorten molding cycle.
  5. This design approach requires a reduction in the overall cost of mold and production.

Some suggestions for treatment of steel in processing of plastic crates: At beginning, structure must be designed first, and choose a material formula according to designed structure, to ensure mold base, mold core cavity, slider section can be used scientifically. Mold steel used is recommended to be treated three times. Firstly it is quenching and tempering treatment; then it is vacuum treatment with a vacuum of 42-46 degrees; Finally ensure temperature is tempered for 48 hours. It is very important to control distance between mold steel in furnace to ensure that each treatment is uniform. If treatment is not proper, uneven hardness will easily cause mold steel to rupture.

Plastic crate mould materials are selected according to specific conditions and customer requirements. Suggestions here: If our mold usage rate is relatively high, 45# steel is generally used. Core, cavity and slider of mold are nitrided 718H. This mold can be used to at least 1 million times. If mold is not used too much, mold frame material is 45# steel, core, cavity and slider on mold are nitrided P20 steel. Mold can be used at least 500,000 times. If number of molds required is only within 200,000, we can completely use ordinary steel heating treatment to meet needs of production and processing plastic crate.

Under normal circumstances, if enterprises that purchase plastic turnover boxes have special requirements, but purchase volume is not large and it is required to customize non-standard plastic crate, then we can open molds. Since cost of plastic crate mould will be higher than total cost, it is recommended to purchase standard plastic crate mould for sale with the closest requirement specification. If order quantity is very large and it is a long-term order, it is still cost-effective to make a special plastic crate mould.

Speciality and uniqueness of plastic crate mould structure design

Mold structure adopts four-way mold opening, two-stage top-out structure, strength and stiffness of large mold for calculation.

(1) Structural requirements for plastic turnover box products. Large-scale plastic turnover box products are used for transportation of canned food, other industrial enterprise products, semi-finished products. That means home appliance mold such as fish crate mould/vegetable crate mould/bread crate mould/beer crate mould are required. So it requires to be shipped in a large volume but light weight, so design weight of turnover box is 2~2.1kg. A single tote is loaded with 65kg and can stack up to 7 layers. Therefore, bearing strength is above 50MPa. At the same time, it is required that turnover box products fall from a height of 20m without being damaged. Therefore, structure of the turnover box product is designed to have five sides (four sides and a bottom surface) all having reinforcing ribs.

(2) Large turnover box injection mold design.

(3) Evaluation of effect of production completion quality inspection. Through more than ten years of injection molding production practice, from 4000g to 10,000g large injection molding machine production, turnover box production has formed serialization and standardization. Through years of production practice, above-mentioned design concept of turnover box mold have been widely accepted by several plastic injection mold maker and have produced good economic efficiency also.

For a long time, Hafo Mould Industry Limited, as a professional plastic injection mold maker for home appliance mold, has always adhered to principle of “independent research and development, continuous innovation, quality first, customer first”, taking road of product diversification, continuously integrating modern technology production, design technology, and developing new products . Customers all over the world more than 50 countries, our company’s products in plastic turnover box, plastic trays, plastic turnover basket industry has been widely used, won industry’s unanimous praise.