Home » Plastic Injection Molding in China
Plastic molds should not only emphasize product design and price, but also plastic mold manufacturing, quality, cycle, and service.
Injection mold is an indispensable tool for producing plastic products in the process of industrial development and mass production. It affects the complete structure and precise size of plastic products. Injection molding is used in mass production of plastic products. The processing method specifically refers to that the material that is melted by heat is injected into the mold cavity by high pressure, and after cooling and solidifying, the molded product is obtained.
Injection molding can realize one-time molding of plastic products with complex shapes. It is a high-efficiency, high-volume production method. The advantages and disadvantages of injection molds directly affect the quality of injection molding. In the mold industry, to produce high-precision, high-quality, complex-faced injection molds, it is necessary to use advanced computer-aided design and manufacturing software to compile a reasonable process specification, which is to ensure the processing quality, improve production efficiency, reduce The effective way of labor intensity.
The mold is the mother of industry. The mold makes it possible for goods to be produced in large quantities. Various kinds of precision equipments are needed in the process of producing injection mould in injection molding factory. What equipment does the injection molding factory have?
Shenzhen: The machinery industry has always been a traditional advantage industry in Shenzhen. At present, there are more than 12,000 mechanical production and operation companies in the city and nearly 850,000 employees. The annual output value of the mold industry in Shenzhen accounts for about 25% of the country's total. Stamping die and die casting die are known at home and abroad for their high precision, good quality and fast delivery. In 2007, the Shenzhen mold industry base covering an area of 1.6 million square meters has made breakthrough progress. The first-phase settled enterprises have started production in succession. A batch of digital versatile and specialized equipment manufacturers have developed well, the Shenzhen brand for mechanical equipment manufacturing has been launched in the market. Shenzhen is also the world's largest micro-motor production and export base, and the machinery industry has become the second pillar industry second only to the electronic information industry.
It is very important to choose a good mold manufacturer, because they not only can provide you with satisfactory molds, but also can make the after-sales easy. When the customer encounters a production problem, they can also consult these professional mold manufacturer, they will provide good advice to customers in many aspects such as design, production, etc., can save costs, improve efficiency, let customers sell products with better reputation and price during the use of customers. And that's a good business cycle what I've been looking forward to in the mold manufacturing industry. 
As having been the Asian tooling manager for a prominent US company for the past 15 years I can attest to numerous hot runner problems. Most hot runner problems resulted from the hot runner/injection mold system going through revisions in material (resin) changes which had significant effects on the basic design of the hot runner delivery system and components. This is why I suggest that in a high volume application, it is wise to validate a part design using a conventional drop mold before diving into a costly hot runner manifold. There are dozens of hot runner manufacturers in China alone, the Good, Bad and the Ugly. If the cost is the main driver of supplier selection----Good Luck !!! If however you have a part/program that deserves a quality hot runner system, which affords you the technical and field service support, your choices are few, and this would be based on the injection molding location. Sure there are single "Hot Drop" components that fill the need of many applications and are quality products, but I don't consider these products to be a substitute for multi-gate hot runner manifolds, nor do they serve the same purpose.
In my opinion, there are several reasons for Chinese mold makers like to use fake material to make molds:
  • No industrial standard for mold. The governments have no interesting to improve mold industry, just care about their tax income.
  • The cost of punishment is too low to mold supplier to use fake material. In China, this situation is very bad. Even the foods are made from bad or fake raw material. The governments few punish the fake things maker, if the bad thing not threaten the social stable. They do not concern that if the fake material mold damage abroad clients' interest. On the mold maker side, what their lost is only a client, no body to punish them. It seems like Zero risk to use fake material to make fake material mold. It is luck to meet a serious mold maker in China.
  • The buyer should believe that what you get is what you pay. Sometimes lower price is unreal.
We paid high school fees as you call it for faulty/inferior molds from China. The only way to deal with a Chinese mold maker is to specify the grade of material you want, shore hardness, heat treatment and certification on the quality of steel on the molds. The guarantee from any company in China is not worth the paper it is written on, unless you are willing to ship any product back and forth to China at your own cost for repairs.

Get tool drawings first and get a qualified designer to check them and accept. On completion of mold do a minimum production run of 3 days and see the quality of the product. If you are happy with what you have then get them to strip the mold and check for any wear and tear on mating surfaces. If this is ok then purchase it and the production run. Trust me this is the only way as I am still recovering from the financial loss from 10 years ago. This is what we do now and it seems to work.
Not being in the injection molding industry, I was looking for tips on how to judge a company or factory on their capability or capacity to do a particular job. In China, everyone is a molder. However, I have noticed that if you ask people as to their ability to hold certain tolerances, they will be truthful about it.Injection molding factory I am not saying that they will be able to produce plastic parts even to tolerance levels they clam, but I think that eliminates probably 90% of people who may respond. I still have to go into it deeper, obviously, but it is a start. So visit to a factory is an absolute necessity. My problem is that my plastic parts are very thin, with a profile on o.d. and I don't know many plastic molders, and certainly any capable of doing these plastic parts. In addition, these are reverse engineered parts, and not being able to lay my hands on spares I am trying to keep my tolerances as close as possible to avoid problems with tolerances. So at this time I am just trying to develop a list of companies that think they can make my custom plastic parts by sending them drawings. If they say can do this and provide tolerance level they feel comfortable with, I ask them for an RFQ. I will then follow up with a tour.
But I believe the best way might be to make a small injection mold to test their ability, just to keep my exposure as low as possible and test the plastic molder.
Current situation live in China...US plastic injection molding company scheduled staff in China for 6 days of mold trials beginning February 4. Tooling fixtures and components necessary to run the plastic injection mold trials are stuck in customs and customs is demanding >25% of value of these components to release them. My previous experience has been 17% import duties/taxes (regardless, delays are not uncommon if you are not familiar with the paperwork necessary to make a successful clearance).

This is only one example of hidden costs, more obscure than some mentioned above. If I was managing a plastic injection mold build project, I would have to take a look at the big picture regarding China or America. If it was a one-time deal, I would manage the plastic injection mold project through a reputable broker in the US. In this way I can be confident with TOTAL costs up front and avoid the agony of putting up a number to my customer for the price of the plastic injection mold project and then watching my margin slowly erode as the build progresses.
Many companies I deal with see a plastic injection mold tooling quote and never add in the "extras".
I have been sourcing plastic injection molds from China for over 15 years and here is my list of concerns buyers have mentioned.
  1. What is the real landed price to my factory.
  2. Understanding that the PO is for good parts/tool to run to EAU for X years not just samples.
  3. Who covers all the freight cost for samples sent from China.
  4. Are components used in injection mold tooling available in US.
  5. Does PO for tooling include all CAD files required to make domestic plastic injection mold changes.
  6. Are CAD files updated to reflect the actually injection mold tooling being shipped.
  7. Was the plastic mold tooling sampled in an equivalent machine to the one it will run in in the US.
  8. Did the plastic injection mold run for 24 hours or just long enough to get enough samples.
  9. Did you receive parts on the runner and not groomed, that will tell you a lot about what injection mold is being shipped to you.
I have met so much the plastic injection mold manufacturers in South and East China. But the problems are following:
1) In China the workers want to earn the money and the owner want also earn the money in the short time. So you could not easy to find some good worker, who could do the job for many years. If the owner find out they could not earn so much money, they could invest in other area.
2) There are really the different culture between China and West. If you find in other country, you will find such different in India, which make also injection mold business, and South Korea. I think the reason is, how long the injection mold industry could be developing in the country. If the total mold industry would be developed so good, you will find actually there are no so much different.
3) About the price. Why the customer in EU and USA buy injection molds in China or India, South Korea. Only because the price. The most of them do not calculate what behind such low price. If you only want to buy such mold with low price, you must accept the quality. Just like you in EU and USA.
4) Some company could also make very good plastic injection molds, but the price for some companies from EU and USA could not accept them. And the owner would also like to get big order.
1 2
Featured Articles
Plastic Injection Molding Process ... Plastic Injection Molding Process SimulationThe propositions behind injection molding process simulation are very basic. First, that although our plastic materials and ...
Visit injection molding factory in ... Visit injection molding factory in China before closing the dealNot being in the injection molding industry, I was looking for tips on how to judge a company or factory on their capability or ...
Injection Mold Cooling Design Injection Mold Cooling DesignThe design of the injection mold cooling system is very important. The cooling time takes up 70% to 80% of injection molding ...
Plastic injection molding hot runner ... Plastic injection molding hot runner systemHot runner is a set of temperature control heating-device, installed in the plastic injection mold, it is part of the mold. A Hot ...
How to choose plastic injection mold ... How to choose plastic injection mold steel?Hardness and wear resistance Surface roughness, dimensional accuracy of plastic parts and injection mold life heavily rely on the ...