In this article, we aim to help you in your molding supplier search, we have compiled information on the top custom plastic injection molding companies in CHINA. Domestic Custom Plastic Injection Molding Companies We have compiled a list of plastic injection molding companies and mold manufacturers with information on all the CHINA providers of custom injection molding services. Companies are ranked in descending order of company size in number of employees.   Company Headquarters Number of Employees HS MOLD COMPANY Dongguan 100-199 WENYI THINITY CO. LTD. Tonglin 100-199 Changhong Technology Company ShenZhen 100-199 Shanghai Kroning Technology Equipment Co., Ltd. (Kroning) ShangHai 100-199 Sichuan Yibin Push Mold Co., Ltd. (Push) SiChuan 100-199 Shenzhen Xubang Manufacturing Technology Co., Ltd. (Xubang) ShenZhen 100-199 Himile Group Co., Ltd. (Haomai) Gaomi 100-199 Kunshan Daliang Plastic Mould Co., Ltd. (Daliang) KunShang 100-199 Weihai Youshan Precision Mould Co., Ltd. (Youshan) WeiHai 100-199 Shenzhen Jinggongda Plastic Mould Co., Ltd. (Jigongda) ShenZhen 100-199 Table 1: Top Domestic…

Here are some steps you can follow to find a reliable mold maker in China: 1.Research: Start by researching different mold makers in China and make a list of the ones that seem promising. Look for reviews from previous customers, and check if they have a website with detailed information about their products and services.Ask for referrals: Ask other manufacturers, industry associations, or trade organizations if they can recommend a mold maker they have worked with in the past and trust. 2.Check their experience: Look for mold makers with a good track record and a substantial amount of experience. It’s also important to verify that the mold maker has experience working with the type of mold you need.Review their facilities and equipment: Make sure the mold maker has the necessary equipment and facilities to manufacture the mold to your specifications. 3.Good communication is key to a successful collaboration, so it’s…

China’s automobile production and sales volume has ranked first in the world for 11 consecutive years. China ‘s market share in the global automobile manufacturing industry had increased from 13.78% in 2008 to 28.23% in 2019. Affected by the COVID-19 epidemic, China’ s automobile production was affected to some extent from 2019  to 2022. Statistic data shows that in 2019 China’s automobile output was 255.3 million units down 8% year on year, and from January to June 2020 was 99.7 million vehicles, down 16.5% year on year. The continuous development of the automobile industry has driven the growth of the auto mold market demand. Update new model will bring new market opportunity With the intensified competition in the automobile industry, the OEMs will choose to upgrade new models to attract consumers and maintain their brand influence among the consumers.  Therefore, auto makers in many cases have chopped the time it takes to develop a…

Are you trying to find a plastic injection mold manufacturer in China who is well-suited to your needs and can also deliver on their promises?And if you are new to sourcing from China, the first thing you should do is to overview the internal characteristics of tooling companies for better understanding and support of proposed business models. Here are the questions you should ask before asking quote from a tooling shop in China. Is the tooling shops foreign invested or Taiwan/HK Invested or Private ? This is an important question as the type of the company may impact your mold cost greatly. In general, there are 3 types of mold companies and each has their advantage and disadvantages. A. Starting from 1990s, many US and European plastic tooling companies started building their own facility in China according to their industry standard. In early stage, larger plastic factories were mostly founded by entrepreneurs from Western countries. In terms…

Plastic injection molding is the process using polymers or plastic resins that when heated, melted and injected under high pressure into a custom injection mold, will produce plastic parts to be utilized in product manufacturing. The manufacturing process can be a complicated one and there are many factors such as industry needs, specifications, end-users time/budget constrains to consider when choosing a plastic injection molder in China that best suits your production requirements. Volume Specialization & Capacity: With more than10000 injection molders of different size all over China, selecting the best injection company for your project can be a chanllenging task. The best is to start with narrowing down your options according to your volume and size requirements. High volume molders specialize in project requiring over 500,000 parts and typically produce parts requiring small-sized molds and press under 350 Ton. Usually the injection machines are equipped with robot systems to increase efficiency while saving more pennies. Low to moderate volume molders…

A client who just start s up his new injection molding company recently inquired me about how to qualify Chinese supply chain for injection molds.  It is said that choice is more important than effort. Yes, choice is more important, choose correctly is far more important. Only by going in the right direction, your road will be smoother, otherwise, no matter how much effort you put in, all will be wasted. This is very true for selecting a qualified mold maker from China . A good mould manufacturer  save you a tremendous amount of time, money, and headache without sacrificing quality. In this article I’ll explain how we could go from having no contacts in China to successfully complete audit on injection mold manufacturers.   1 Start building a list of 5 suppliers with whom you can communicate directly.Comb through the different resources to search and identify the appropriate manufacturers for your injection…

China has started ban of the production and sale of cars using traditional fuels. At present, Nissan, BAIC, Volvo, Changan Automobile and other car companies have announced their schedule of phasing out fuel vehicles and move towards of development of new electric vehicle.  However, subjected to the mileage of electric vehicles, lightweight issue has become one of the tops ones that needs to be addressed urgently by vehicle manufacturers. Therefore, Micro-foam injection molding technology technology is more and more widely used.     What is Foam Injection Molding? Injection Foam Molding is a low-pressure process where molten resin is injected with nitrogen gas or a chemical blowing agent. The resin is then shot into the cavity, without overfilling or packing it out. The blowing agent or gas then expands to push the molten resin to the extremities of the cavities. As the part cools, the internal pressure of the foaming action takes up the internal shrinkage and reduces sinks over ribs or heavy cross-sections.  …

Have you ever met the case when the cavity steel has been polished as high as possible but the ABS molded part is still not at the gloss needed? The problem may be related to mould, material, processing, or combinations thereof. Look at below information to find the root cause.   Plastic injection Mold   Surface of cavity steel is not clean Oil or water stain on the surface of cavity steel, and too much release agent applied during the process of abs injection molding, all this create a dull appreance. In this case, clean the mould and control the use of mold release agents.   Mold or Part design   When the wall stock varies, it is very difficult to maintain consistent gloss on the part. Depending on the flow pattern, thinner wall sections may not be exposed to as much plastic pressure, and the result is excess gloss in that area. The same effect can happen when the…

Thermoplastics shrink as they cool and solidify during the plastic injection molding process and after part ejection.   The plastic injection mold cavity is machined larger than the final desired molded plastic part size in order to compensate for part shrinkage as the part cools.   Mold shrinkage data for the specific plastic material can be used to calculate the amount of mold expansion needed.     Shrinkage in mould units are expressed as length-per unit-length, or as a percentage, and is calculated using the following mould shrinkage calculation formula :     (mold dimension – part size) / mold dimension  = Mold Making Shrink Factor   We could alse use a simplied formula as below.   S={(D－M)/D}×100%(1)   Shrinkage； D-Mold Size； M-Molded part size   However, since the actual shrinkage is influenced by many factors, only the approximate value can be used,When building the mould, the cavity should be machined according to the lower deviation while the core be machined according to the upper deviation to leave…

What is delamination/Peeling? Delamination is thed detached, slate-like surface layering of the polymer as it fills and packs the plastic injection mould tools. With this defect, different unconnected layers of plastic develop and form within the plastic injection molded parts. , e.g. due to cross cutting. usually not easy to identify since the surface is flawless; a “skin” can often be pulled off when the surface is scratched with a blade. The molded plastic product exhibits bubbling after warm storage. The cause of delamination High shear stresses result in the formation of layerseven in compatible multiphase systems during injection molding process. Contamination with an incompatible thermoplastic or master batch Sharp Corner around the injection gate and runner in the plastic injection mold Correction Increase the melt temperature and reduce the injection speed. Avoid contamination due to extraneous material or due to an unsuitable master batch (specifically the carrier) Channge all shapr corners to be round corner….

What is weld lines in injection molding  During the manufacturing of injection molding process , the Weld lines , also calles as Knit lines or Meld lines are present on the surface of plastic molded parts where two flow fronts meet and when they are not able to to “knit” together, or “weld” together .These harilines or dark lines usually occur around holes or obstructions and cause locally weak areas in the molded resin part. Appearance of weld lines in injection moulding  Notches, hairlines Change in apparent color; especially when inorganic decorative effect pigments are used the weld line appears as a dark line; conspicuous in dark, brilliant or transparent moldings having smooth surfaces polished to a high gloss. Cause of weld lines injection molding Appear in multiphase systems such as ABS or ASA. Flow fronts having an already cooled peripheral layer encounter one another and no longer allow fusion without marks. Decorative effect pigments and, e.g., glass fibers tend to straighten up in the…

As known, the manufacturing of plastic injection mold determines the quality of plastic molded parts, production effieciency and cost of finished products.Mold trial is run to solve any problems with the design, resin, tooling,machine. Thus procedures of mold trial is very important for a injection molder. Be sure to follow this nine-step process to make sure you’ll be making good parts through a successful trial.   Firstly, Keep the  injection mold run on the press without any resin to verify the function of  the mold    A. Check mold opening and closing condition at low pressure:   Mold should beopened and closed by 3 times at fast, medium and slow speed. During the process, there should be no abnormal sound nor block phenomenon;   Mold opening and closingshould go smooth  without any interference.   B.Checkejection system of the injection mold (at low pressure)   1.Check the ejection action at  fast, medium and slow speed.   2.Check whether ejector pins  or sleeves on the…

Want to know how to optimize your plastic part design for manufacturing with uniform wall thickness?   Wall thickness is one of the most important rules of injection molding part design that you should treat it as an essential part of your overall part design This is especially important as wall thickness is considered as one of the most importnat factors that determin the success or failure of the plastic product. In this article we will explore  the importance of maintaining uniform wall thickness to get your project going successfully Why maintain uniform wall thickness?   Metal parts are often designed with thick walls, while plastic products should ideally maintain uniform wall thickness for uniform flow and less shrinkage as illustrated as below. For plastic parts, a gradual change in wall thickness or uniform wall thickness is recommended to reduce stress concentration and other potential issues. Why do we attach so much attention…

What is double ejection? Some complex plastic parts often have undercuts that are too deep to be ejected directly by neither lifters nor slides.  After ejection, the molding parts may still rest on top of the ejector pins,so another stage of ejection is needed to clear the parts. This typical solution is called double ejection system which  s can be a mechanical system driven or supplemented by air or hydraulics.   Second ejection mechanism： Add an extra set of ejector plate. The first set of ejector plate that is attached to the A plate(referred as Ejector Assembly A) is to complete the first stage of ejection while the ejector plate attached to B plate (referred as Ejector Assembly B)  is to complete the second stage of ejection as shown in Figure1. Figure 1 Add series of springs or nylon plugs to make sure that both ejector assembly A and B are attached…

 Basic function of gate   The gate is the bridge of runner and the cavity, and also the last stage of injection system of injection mold.   1) Enforce the molten plastic from the runner to enter each cavity at the fastest speed.   2)Once the cavity is fully filled, the gate can be quickly cooled and sealed to prevent the uncooled plastic in the cavity from returning.     How to design gate   There are no set rules to flollow on how to design the injection gate. It is done mostly based on experience, but there are two basic elements that must be considered:   The larger the cross-sectional area of the gate, the better, and the shorter the length of the gate, the better to reduce the pressure loss when the molten plastic passes through.   The gate must be narrow in order tomake the gate cool down easilyand…

This is a set of high precision plastic mould for Portable Vacuum Cleaner  It is Vacuum Inlet Elbow. This type of plastic tooling is usually structured with oil cylinder core pulling or arc core pulling, which is a typical structure of automotive vacuum cleaner molds. The product has 3 undercuts. This is how we solve the undercut：The undercut 1 and undercut 2 use cylinder core pulling , and undercut 3 uses Angular pin  + spring core pulling.   The mold injection system adopts nozzle, cold runner and edge gate, 1*2   The undercut 1 adopts a built-in slide structure, and dovetail groove is used to guide the silde and retract from the undercut.   Mold ejection   Mold cooling     Mold overall structure   CAV We are a mold company based in that manufacturing Custom Molded Prototypes and Production Parts with Fast Lead Times

What proper gate design is important? The gate serves as the entrance to the mould cavity and should be designed to permit the injection mold to fill easily. It is very important to follow below gate considerations while picking gate location at the early stage of plastic mould design. Gates should not be placed where part-bonding or impact will take place in use. The gate area will usually have higher residual stresses than the rest of the part due to the packing that takes place. Therefore, it will be weaker than the rest of the part. Position the gate to minimize trimming problems. Scissor-type gate cutters, kept sharp, will work smoothly and leave no “blemish” marks. If possible, gate into the thickest section to avoid incomplete fill or sink marks. This will also minimize flow marks and distortion associated with setting into a thick section from a thin one. Position the gate so that venting…

It is rare to see the structure of slide coming out of lifter in plastic injection molds. We are not experts, but we just design a typical mechanism that works quite well based on our experience.  Hope that it helps you. Mold Design Concept If we use common mold slide, the steel circled in red get stuck. And the undercut could not be released with this. How to design lifter head?   Green block is lifter with a prominent tail while the purple block is slide which is to release undercut and drive lifter to release undercut downwards. Further explanation on slide out of lifter in plastic injection mold Mold lifter needs a limit screw to limit the stroke of lifter travelling down while the spring is to prevent lifter from moving right with slide The science of structure of slide from lifter   Angel lifter drive slide to move right And…

        Every mold maker knows that proper mold venting is crucial for manufacturing quality plastic injection molded parts. During the injection molding process, the air existing in the mold needs to be released, otherwise the melt will compress and trap that air in the cavity, causing burnings,short shots, bubbles, welding lines or cracks in the molded plastic part. How do you vent the mold? There are a few nonstandard venting solutions that can be added to cavity venting to improve mold performance as below: Open vent groove directly Usually the vent groove, or vent channel are machined on the flat surface in either peripheral or direct way. There are primary and secondary venting channels.          Use clearance of ejector pins and ejector sleeve.       There is clearance of around 0.01-0.02mm between ejector pins & ejector sleeves and core/cavity. This could be used…

As COVID-19 pandemic continues to impact every part of our lives, the usual routes of travelling to China and visiting tooling shops are not accessible during this time of social distancing..Meanwhile, the number of mold makers in China grows exponentially every year. Now you can use the internet to search for the right molding company,but the stream of websites will be overwhelming for you to narrow down. How can you separate the reliable ones from those who are not up to the standard? These are the things you need to consider when you’re looking for a good mold maker in China. Check if mold makers offerPrototyping Services A good mold maker respects your idea and turns it into reality. Request prototypes to test your product’s feasibility or if you just want to see how the part will look. Prototyping is a way of making a finished product without building a tool by means of CNC machining ,3D printing or…

This is a cut in solid injection mold for auto part mold and the materiaL is PA66+30%GF.This big guy have 4 big slides and one smail inside the big one. HSmold can guarantee a mold life of at least 50,000 PCS. Our factory is equipped with various size of injection machine ranging in tonnage from 55 tons to 610 tons and shot capacities ranging from 1.3 oz to 80 oz. We can meet any of your custom injection molding needs using different types of plastics including ABS, PC, PP, Nylong and so on. We produce custom injection molded finished products and parts for direct shipment to oversea end customers  We produce standard and custom plastic products for various industries including Automotive, House hold application, Medical and more.  HS MOLD is a manufacturer of thermoplastic injection molding services including new product development, plastic mold design, mold making, custom injection molding, final product assembly, mold making, and prototype…

The PVC Pipe Fitting Elbow are mainly used  as structural parts in automotive and home appliances, such as  Elbow Auto Parts , Vacuum Cleaner Hose Elbow Handle etc. Relatively speaking, vacuum cleaner products are second only to OA office supplies and auto parts in complexity. The following is a set of elbow mold that we have designed and made in house. HS Mold is a leading manufacturer for PVC pipe fitting mold, pipe fitting mould, pvc ball valve mold and pvc pipe fitting mold manufacturers ,pvc plastic pipe fitting mold, pvc pipe fitting injection molding, PP-R molds in house in Dongguan.

Shrinkage is a characteristic of resin which occurs during plastic injection molding process. Different resins have different mold shrinkages. Crystalline and semi-crystalline materials exhibit higher shrinkage than amorphous materials. Unreinforced plastics have higher shrinkage than reinforced grades. It is important that the grade of material be selected before the injection mold tooling is constructed and that the proper mold shrinkage be specified.   Mold shrinkage rate can vary with part and tool design: thick walls will have higher shrinkage rates than thin, variation in section thickness can cause differential shrinkage and warpage;flow direction will effect shrinkage,particularly with glass fiber-reinforced grades       Shrinkage in mould is also influenced by process conditions. As cavity pressure increases,shrinkage typically will decrease. The plastic injection mold and melt temperature will also influence shrinkage. Cooler molds will reduce shrinkage while hotter melt temperatures will increase shrinkage especially with semi-crystalline materials.   Contact HS Mold Company for shrinkage recommendations on any of plastic injection molded products. We…

Glass fiber reinforced plastic are composite materials made of polyester, usually thermoset resin,glass fiber and filler in custom fiberglass molding  process. Generally speaking, most of the glass fiber reinforced materials can be used to create large, complex structures in any number of geometric shapes, including contoured and rounded FRP Molded Products.  Thermoset polymers used as resins in the manufacture of reinforced plastic includes PP, ABS, PA66, PA6, PC, POM, PPO, PET, PBT, PPS, etc.. Fiber reinforced plastics are overall a highly advantageous material providing a number of benefits in a wide variety of areas from physical properties to resistances to aesthetics.   Advantage of glass fiber reinforced plastic 1.Glass fiber reinforced plastic is a high-temperature resistant material, therefore, the heat-resistant temperature of reinforced plastics is much higher than that non-reinforced polymers, especially nylon plastics.  FRP is a durable material which can last years in extreme hot weathers and temperatures with minimal wear. With theaddition of glass fiber,the reinforced plastic restricts the plastic movement between the…