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Plastic Injection Mold Making Process



As a good reputation manufacturer in China, we here share the basic injection mold making process in our company:
1. Products design department provides product information to injection mold design department, injection mold designers complete cost analysis in two working days, and provide to R&D manager.

2. R&D department release "Mold Making Apply" to plastic injection mold design department after confirmed the project.

3. Injection mold designers organize relevant personnel to review the project base on the product information, including product structure, mold structure, cooling system, runner, slag, venting, etc.Mold Making Process

4. After evaluation, injection mold designers begin to design the plastic injection mold, including 3D drawing correction, 3D parting, mold parts assembly drawing, EDM drawing, electrode drawing etc., and organize relevant personnel to evaluate those drawings, then issue to plastic injection mold making department.

5. Injection mold makers evaluate and study the drawings, and order mold materials if there is no objection, otherwise, communicate with the plastic injection mold designers.

6. Injection mold makers inspect the mold materials in time after the materials arrive to factory, and arrange technicians to do locksmith works, include turning, grinding, milling, screw holes, water carrying hole, center hole, CNC roughing, etc. The technicians should pay attention to the precision of each right-angle sides, avoid empty of the center hole and each production base, roughing margin etc. Then outsource each mold part to heat treatment promptly.

7. After heat processing, plastic injection mold maker must detect its hardness and metallurgical analysis. Generally, the core hardness 46-50HRC, for uniform distribution of 9 points, requiring its hardness differ is less than 1HRC. Metallurgical analysis should be done for the injection mold core prior to processing to make sure there is no segregation, scars, etc.

8. Electrode processing, there are fine and rough processing, fine male spark is 0.08, rough male spark is 0.2 (subject to the actual situation). Be sure to pay attention to each processing benchmarks, and detect electrodes after processing finished.

9. Before finishing, must make right angle for the mold core, the vertical degree should less than 0.02 mm, finish degree 1.6.

10. For line cutting, please note that all parts' base, enlarge 0.02mm for the insert hole and center hole as tolerance clearance, for non-standard thimble, the tolerance clearance is 0.04mm of the actual thimble size.

11. Mold core finishing, shall base on the benchmarks after making right-angles, typically leaving 0.02 mm die as a margin (without considering tool wearing).

12. EDM processing, process according to the drawings' size, fine 0.08, rough 0.2 (subject to the actual situation), pay attention to the benchmarks in processing, for sparks processing, the leave a margin of 0.03-0.05 mm.

13. The runner surface must be polished to achieve ▽6 or ▽7 finishing, the surface does not allow spark or knife pattern exists.

14. Before assembling the plastic injection mold, the mold maker must do a comprehensive inspection for all related parts to make sure everything is in a good condition, and do cleaning and anti-rust treatment. Then fill "Mold Inspection Summary" form.

15. In tryout, injection mold designers, plastic mold makers and die casting workshop personal should go to the site, making analysis and solution of abnormal in casting tryout, improving the plastic injection mold and die casting process according to the results, and fill "Mold Tryout Report".

16. By 100-150 cycle time, the tryout products are defect-free, the production department make production schedule, the technicians track the production processes, and feedback yield to the plastic injection mold making department.

17. After tryout, plastic injection mold making department apply for storage with the forms of "Mold Making Apply" and "Mold Making Inspection".

Welcome to visit our company in Shenzhen China, you will be much happier to discuss technical questions with our experienced mold professionals and manufacture injection molds in our factory.
Injection mold making cost refers to the production cost directly related to the mold making process. There are too many mold types, and there will be differences in cost accounting. But the factors affecting mold making cost are basically the same. Taking the plastic injection mold as an example, to briefly introduce the injection mold making cost:
1. Injection mold base cost
The materials for mold base are usually S45C or S50C. The common mold base is standard parts. Injection molding factory in China generally order mold base of LKM. The standard mold base price is relatively cheap. But for the plastic products with too large size, which exceeds the size range of the standard mold base, requiring customizing the mold base. For example, the size of the commonly used large gate mold base ranges from 150mm x 150mm (referred to as 1515 series) to 600mm x 800mm (referred to as 6080 series). If the injection mold base size exceeds 600mm x 800mm, the injection mold base is required to be customized. The price of customized mold base is 2-3 times that of the standard mold base.
2. The material cost of the injection mold cavity and injection mold core are different depending on the characteristics of the injection molding materials and the mold service life. The commonly used mold steels for cavity and core are P20, 738, 738H, 718, 718H, NAK80, 2316, 2316A, S136 etc. The materials used for the harden mold are 2344, 8407, SKD11, SKD61etc.
ACO Mold is injection molding company located in Shenzhen China. We provide one-stop injection molding mold making service. We have more than 10 years experience in plastic manufacturing industry. In order to provide high-quality injection mold, we equipped advanced a series of equipment such as CNC machining center, engraving machine, spark machine, wire cutting, grinding machine, milling machine, drilling machine and lathe etc. Below is something you need to know about ACO Mold injection molding mold making.
We are a one-stop injection moulding factory that provides injection mould design manufacturing, injection moulding, surface coating, electroplating and product assembly. We have more than 9,000 square meters of standard manufacturing plant, equipped with a full set of precision mould processing workshops and ordinary mould processing workshops, measuring instrument testing laboratory, injection moulding workshop, providing customers with one-stop high, medium and low-end injection moulds manufacturing Injection Moulding Product Assembly Services to meet customer product development needs. The factory is equipped with a series of equipment such as CNC machining center, engraving machine, spark machine, wire cutting, grinding machine, milling machine, drilling machine and lathe etc.

We are ready and looking forward to cooperate with your next project, Contact Us Now, you will be satisfied to choose us as your partner in injection mould manufacturing injection moulding processing.

This injection mold making project is a protective casing for electronic products, the material is ABS.
Analyze the entire process of mold production, establish quality assurance system, and control the key factors that affect the quality of the mold, so as to improve the quality of the mold.
Medical devices usually make direct or indirect contact with human body, it has high standard requirements on mold design and mold making, typical characters of medical parts are high required finish surface, particular structure design, tight tolerance, and food safe material, it is a challenge to the mold makers and injection molding companies.

70% injection molds made by ACO MOLD are exported to US or European companies, these injection molds are usually required to be SPI Class 101, guaranteed 1 million cycles or more, mold standard apply to US or Euro local standard so it can be easily operated and maintained.
Custom plastic parts design sketch
Comparing with stay-in-house-molding mold, the export mold requires a higher capability to mold maker on not just how to make the injection molds but also how to work with US companies. Here we share with you a custom mold making project we have done in our factory, we are sure there would be much more on somewhere we can do much better and achieve much more satisfaction, we summarize it, look back and move forward for better and better customized mold projects made in China by ACO MOLD.


As a custom injection molder in China, we consider first, the requirements of and the complexity of the plastic part that the customer needs. Second, the quality class of the injection mold the customer is paying to have built, quite often the customer will balk at the price paid to get the part that they need, so sometimes there needs to be added language to the quote indemnifying us against the customer rejecting our professional assessment. Third, the type of material that will be run. Fourth, the "production irritation" factor caused by anticipated fill problems and the attendant loss of productivity owing troubleshooting and scrap.

After consideration of the above, we generally use resin makers guidelines for mold vent depths and styles, or our own internally documented design guide based upon experience.
Many Chinese injection mold making companies has also made significant progress in the CAE application, and achieved good results. CAE technology can greatly save the cost of test mode, shorten the development cycle, and has become an important means to ensure injection mold quality. CAE technology is gradually changing the mold design from experience to scientific.
Auto parts
At present, the China auto parts of high strength steel plate is also limited to structural parts and beam parts, the tensile strength of materials used in the 500MPa or less, therefore, quickly master the high-strength steel stamping technology is Chinese automotive mold industry to be resolved important questions.