Post-processing technology of injection products

 

Post-processing technology of injection products

For printing on the surface of the plastic products, printing or when the pattern. there are several methods.

1, Stencil printing of this method is the most common and also the most one method; they are generally suitable for flat or curvature of the small print.

2, The principle of curved surface printing flexography printing ink is first placed within the text or logo engraved gravure, then copy the text or images onto a surface. The surface will re-use the text or pattern is transferred to the surface of the molded product. And finally through an ultraviolet light irradiation heat treatment or the like so that the ink is cured.

 

injection parts processing-Surface printing process:

Skim A. molded products

1. molded product surface treatment (when necessary)
2. Printing
3. curing inks
4. applying post-processing such as excessive (if necessary)

injection parts processing-Printing Process

1. Gravure ink into the.
2. Scrape off the excess ink.
3. Extruded surfaces are made of ink.
4. The surface of the ink transferred to the surface of the molded article.
5. Cleaning surfaces, layout (if necessary), and printing will start with version patterns or patterns printed on the plastic sheet or rubber roller. The rubber roller will no longer sheet or pattern or pattern onto the surface of the beer.

Pros: Several colors can be applied in a single operation.

Disadvantages: lower productivity and not getting opacity strong prints. How to choose a suitable plastic sheet or rubber roller and oil, and so on.

1， The use of hot stamping foil and the color pattern engraved or font of the hot mold. Under controlled temperature and pressure. The surface of the emboss pattern of manufacturing color package or method of beer font member. Which is mounted on the operation only by fixing the press hot mold foil color on regional products across the pressure needed to be applied.

2, The paint surface treatment of plastic products (color) of the most commonly used techniques,

Can be divided into:

A general coloring, that this spray paints mostly by hand, do not have strong abrasion, easy to paint chips.

B, PU grade varnish this method is finished after the spray drying primer, then spray on the surface layer of the PU varnish method to achieve abrasion and gloss. General home appliances or many everyday items are through PU surface treatment.

C, UV grade varnish finish this method after spray primer and then sprayed with a layer of surface UV varnish, gloss, feel, rubbing can achieve very good results. General phone mold products and communications products die with such an approach.

 The use of the electrolytic plating method is electroplating the metal or alloy deposited on the surface, to form a uniform, dense and good adhesion of metal layers, called plating. Simple to understand, the physical and chemical changes, or in combination.

Purposes: a. Corrosion b. Protective decorative c. Anti-wear d. Electrical properties: According to parts work requirements, providing conductive or insulating coating performance e. Process requirements

The surface of the article by electrolytic uniform, dense, with good metal or alloy deposited layer forming process. The process is a relatively complicated process, but it has many advantages. Such as many types of deposited metal can be obtained in various colors, with Compare similar process being relatively cheaper than in terms of prices.

What is Custom Plastic Injection Molding

 Most Chinese injection mold manufacturers complete international trade by providing customized services, but lack of real understanding of the real meaning of customers’ need for customized services, resulting in some mold manufacturers can not accurately complete the highly specialized manufacturing after signing contracts.

Just because a mold maker can facilitate the development of the original mold does not constitute real customer service (or ensure an ideal result). These mold manufacturers lack the ability to export complex injection molded parts for experienced reasons to complete with standardized specifications and tight tolerances.

How to evaluate injection molds consistent with your project needs is a critical criterion for project success. For example, components used in medical or aviation, automotive applications need to be truly sophisticated in design, engineering, and equipment use, compared to common civilian products.

Experience has the rich injection mold division’s concentration and the actual field ability. plastic molded parts used in such applications must comply with strict inspection specifications and compliance assembly instructions.

CNmoulding Industries specializes in plastic injection molding in China to produce a wide variety of products from high-tech parts with very tight tolerances to consumer products, lawns, and gardens as well as entrepreneur’s inventions. We provide custom plastic injection molding for customers worldwide, in a variety of industries. We are the low-cost leader for high-quality injection molded plastics with a fast turnaround. Some examples of these products are pictured on our web.

We manufacture large and small moldings. we can manufacture almost any plastic part for any of your needs.

High volume custom injection molding capabilities

 Precision tool makers in our Factory allow us to provide quick-turn service on medium to high volume orders, where we build dedicated long-run production molds. We specialize in high-volume custom plastic injection molding projects. High-end second-op machining is also available. Our plastic injection factories in China manufacture very high-quality products that are extremely cost-effective. Custom injection molding in China is especially effective when the plastics require secondary operations for completion. These secondary operations include anything from cleaning parts, overmolding, painting, drilling holes, pad printing, screen printing, or partial sub-assemblies.

Before releasing it, we will make a packing inspection to ensure all the components, accessories, and documents have been enclosed.

Documents enclosed:

• Inspection Check for Shipping
• material Certification if need
• Latest Injection Report
• Drawing for Components of Mould
• Final Mold Layout
• Share Components List
• Feedback Form of Mould Quality

Custom Injection Molding Actual Performance

Rapid Turnaround: We offer the most efficient, safe, and affordable transportation

the method, our special channel shipping price is cheaper than any customer’s own forwarder price to suit your time and budget requirement.

Online Quotation: We provide a standard quotation for custom injection molding 24 hours in time through EMAIL, WECHAT, WHATSAPP, and SKYPE interactive online quotation system, also including mold and rapid prototyping parts processing.

Low Cost:  20 years complete supply production chain layout, so that we really complete each link of high efficiency, fully reflect the offshore manufacturing industry with a lower cost structure of facilities, in order to provide prices below our pure domestic competitors.

High Quality:  We are ISO9001：2015 certified, use CMS digital system so that the full qualified rate of mass product manufacturing is possible. The whole process of digital management makes the traditional manual single-piece measurement method can not compete.

A real example of custom molding TESLA Motor parts

CNMOULDING customers come from a variety of world-renowned automotive industries, such as electric car industry leader Tesla Motors. Electric cars have a large number of electronic parts to replace traditional car hydraulic parts, plastic shells need to protect the subtle automotive electronics parts, safely consistent with the brand established by Tesla. this is a high order for an offshore Chinese supplier, but we consistently produce and deliver quality parts that meet the required specifications. The injection mold is perfect for an enviable position.

The customer takes the initiative to cooperate with us. because producing specialized, complex solutions is commonplace. These include all kinds of car buckle, protective cover, decorative panel. produce $3 million of molds and automotive products annually.

our technical department works closely with the engineers of the customer to optimize the component design to reduce the development cost, introduce Moldflow analysis, identify and correct the problems that will be in molding and materials in advance before production. Custom features also allow medium-term production adjustments, including components modifications after assembly. The result of custom injection molding is quite different from that of the traditional mould.

 

5 types of mold surface treatment

 

5 types of mold surface treatment

 

The application of surface treatment in the mold is the most effective way to provide mold quality and service life and reduce cost.

By adopting different surface treatment technologies, only the composition, organization, and performance of the surface layer of the mold can be changed. Thus greatly improving and improving the surface performance of the mold. Such as hardness, wear resistance, friction performance, stripping performance, heat insulation performance, corrosion resistance. And high-temperature oxidation performance. The special properties of the cavity surface, such as anti-scratch ability, release ability, anti - bite, etc. Several times, dozens of times to improve the service life of the mold.

It is of great significance to improve mold quality, reduce the production cost, improve production efficiency. And give full play to the potential of mold materials. What methods of injection mold parts surface treatment in China?

The effect of injection mold surface treatment

1，Plastic Mold Parts

In-mold processing, the surface treatment can make the parts for the following properties: Increasing surface hardness, increase the compressive strength, abrasion resistance, improve corrosion resistance, and improve sliding, etc.

2, Plastic Molding parts surface treatment methods.

3, The injection mold Surface treatment method is many in China. But for the injection molded parts, the main methods of surface treatment are the following.

 

1，Carburizing

Carburizing is to the steel surface infiltration carbon atoms. It is to put the parts into can release the active carbon atom medium, heat insulation, make activated carbon atoms permeability and the surface of the steel. Its purpose is to improve the surface of the carbon content, the subsequent heat treatment, the surface hardness increased, While the core remains resilient. Therefore, carburizing steel must be 0.15% ~ 0.25% (mass fraction), the carbon content of mild steel. Methods include solid carburizing, carburizing liquid carburizing. And gas carburizing, which is a widely used gas carburizing.

2，Nitriding (also called nitride)

Nitriding is to the steel surface infiltration nitrogen atoms. Its purpose is to improve the parts table surface hardness, wear resistance, corrosion resistance, and fatigue strength. At present, the most widely used method of nitriding is gas nitriding. It is to put the parts into the airtight furnace, the ventilation with NH3, heating to 500 ~ 600 ℃, the ammonia decomposition of reactive nitrogen atoms. The nitrogen atom is easy to be absorbed by the workpiece surface and spreading inside, forming a nitride layer. The nitriding layer is 0.1 ~ 0.6 mm. The nitriding layer has high hardness and excellent dimensional stability. And can noticeably improve wear resistance and fatigue strength, corrosion resistance has greatly improved. In the mold processing, almost all steel nitriding processing. But it's a longer production cycle, high cost.

3，Hard chromium plating

Hard chrome plating is will adopt the method of plating chromium plating on the surface of parts. Thereby gaining the surface of the hard and wear-resistant. It contains the abrasive plastic molding parts, the hard chromium plating layer is very effective. In addition, the hard chromium layer can not only reduce the wear and tear, and can significantly improve the corrosion resistance of parts. It can also be used when repairing the wear surface hard chromium plating method processing.

4，Hard nickel plating

Hard nickel plating is to use the chemical method will nickel the plating layer on the surface of parts. In the process, the deposition of the nickel layer does not use imposed by the electron flow. so you don't happen like electroplating on the edge, especially along the edge to form the different thickness of electroplating film formation (edge) of the phenomenon. This method of nickel plating in the hole, opening, and the place such as contour surface defects will not appear. The nickel plating layer often about 40 microns thick. It can form has good corrosion and wear resistance of the surface.

5，Coated hard layer

In order to make the part surface with high wear resistance and corrosion resistance. There is new technology is in the surface coated with titanium nitride and similar material for the grass-roots approach. It is easy to operate, and the effect is very good.

Do you have a project need to find china injection mold company today, contact us now

We can give you a good solution for your mold making.

How about plastic injection molding china

 Product Name: transparent products, clear parts,

Transparent plastic material: PC, ABS, SAN, ACRYLIC

Description of products: these are clear products for new medicine and machine, with transparent covers. And supporter, these clear parts are used in America, Europe, Canada, and Australia industrial.

We make the mold in our mold manufacturer factory and then test it in our china plastic injection molding factory.
Plastic Injection molding in China is considered one of the most common plastic part manufacturing
processes. It can be used for producing parts from both thermoplastic and thermoset polymers. The process usually begins with taking the polymers in the form of pellets. Or granules and heating them to the molten state.
The melt is then injected/forced into a chamber formed by a split-die mold. The melt remains in the mold and is either chilled down to solidify (thermoplastics) or heated up to cure (thermosets). The mold is then opened and the part is ejected.

A Typical Plastic Injection Molding Process.
In spite of the relatively expensive tooling cost. Injection molding remains the most popular manufacturing process for plastic materials in mass production. Thanks to its low operational cost, high throughput, and the flexibility to make parts with complex shapes.

Polymers commonly used for injection molding include

• Polystyrene (PS)
• Acrylonitrile Butadiene Styrene (ABS)
• Polyamide (PA)
• Polypropylene (PP)
• Polyethylene (PE)
• Polyvinylchloride (PVC)
• Other short fiber reinforced plastics

General injection molding china  plastics making process

Plastic Injection molding china is used to produce thin-walled plastic parts for a wide variety of applications.
One of the most common is plastic housing. The plastic housing is a thin-walled enclosure. Often requiring
many ribs and bosses on the interior. These housings are used in a variety of products including household
appliances, consumer electronics, and power tools. And automotive dashboards. Other common thin-walled
products include different types of open containers. Such as buckets. Plastic Injection molding china is
also used to produce several everyday items. Such as toothbrushes or small plastic toys. Many medical devices,
including valves and syringes. Are manufactured using plastic injection molding china as well.

The characteristics of precision injection molding

The characteristics of precision injection molding are the size of the injection molded parts with high precision and small tolerance. To achieve the requirements of precision injection conditions must be met:

(1) The mold material is better, rigid, and with cavity dimension precision. And template between positioning accuracy is higher, with lower surface roughness.

(2) To adopt a precision injection molding machine.

(3) To adopt the precision molding process.

(4) To choose suitable for the precision injection molding process of the material. Commonly used precision injection molding materials have several: POM, POM = CF (carbon fiber), PNM = GF (glass fiber), PA \ FRPA66 (enhanced PA), PC, etc.
 
The precision injection process can ensure the size of precision injection molding. Is an important way to control the shrinkage of injection molded parts. Including thermal contraction. Disguised contraction of molded parts, orientation. And compressed contraction and elastic recovery. 

Unlocking Infinite Possibilities for Product Innovation – Your Trusted Partner in Rotary Overmolding Solutions

In today’s competitive landscape, where product excellence is paramount, single-material designs are increasingly inadequate to meet stringent market demands for functionality, aesthetics, and tactile quality.

Are you facing efficiency bottlenecks and weak interfacial adhesion in secondary injection molding processes?

Concerned about inconsistent quality and environmental drawbacks associated with adhesive bonding?

Compromised by visible assembly gaps that detract from aesthetic appeal and long-term reliability?

The solution lies in advanced rotary overmolding technology. What you need is a specialized mold engineering partner with proven expertise.

Why choose rotary overmolding? Advancing Beyond Traditional Manufacturing

Rotary two-shot injection molding is more than a production technique—it represents the convergence of precision engineering and innovative design. By utilizing a fully integrated mold system equipped with a high-precision rotational mechanism, this process enables the seamless co-molding of two dissimilar materials (e.g., rigid and elastomeric polymers) into a single, unified component within one continuous cycle.

Key benefits delivered through this technology include:

Superior Product Performance: Through molecular-level material compatibility and mechanical interlocking structures, rotary overmolding ensures robust, durable bonding between soft and hard components, significantly enhancing structural integrity, longevity, and functional reliability.

Enhanced Production Efficiency: Consolidating two molding stages into a single automated operation reduces cycle time, minimizes labor input, lowers operational costs, and supports scalable, high-volume manufacturing—making it ideal for cost-effective mass production.

With decades of dedicated experience in rotary overmolding mold development, we are not merely mold fabricators—we are comprehensive solution providers spanning concept design, prototyping, tooling, and full-scale production support.

Our technologies have been successfully implemented across diverse industries, including:

Consumer Electronics: Premium smartphone cases, TWS earphone charging cases, controllers, and smart wearable device straps.

Automotive Components: High-comfort steering wheels, gear shift knobs, ergonomic control buttons, and sealing profiles.

Power Tools and Appliances: Ergonomically optimized handles for power tools and heat-resistant grips for kitchen appliances.

Medical Devices: Anti-slip hearing aid housings, patient-comfortable respiratory masks, and precision surgical instrument grips.

 

Overcoming Smart Bracelet Screw Corrosion: A Targeted Solution

 Recently, a smart bracelet designed and manufactured for an Italian client with stringent quality requirements underwent a critical reliability test—metal screws embedded within the plastic housing exhibited signs of corrosion during actual use. Although seemingly minor, this defect not only compromises the product’s aesthetic integrity but also raises concerns regarding its long-term durability and functional reliability.

Screw corrosion is not an isolated issue; it represents a common challenge in plastic-encapsulated electronic devices, particularly wearable consumer electronics exposed to complex environmental conditions. The root cause typically stems from the interplay of multiple factors:

First, as a wearable device in constant contact with human skin, smart bracelets are inevitably exposed to sweat. Sweat contains water, salts, and weakly acidic components that continuously attack the most vulnerable points of metallic fasteners.

Second, early design iterations often employed carbon steel screws with electro-galvanized coatings for protection. However, if the plating layer contains micro-pores, exhibits uneven thickness, or sustains minor damage during manufacturing or assembly, moisture and electrolytes can penetrate through these defects, initiating localized corrosion.

Third, during the insert molding process, molten plastic at high temperature encapsulates pre-placed metal screws. Due to the mismatch in thermal expansion coefficients between metal and polymer, residual internal stresses develop upon cooling. These stresses can degrade the inherent corrosion resistance of the metal components.

Our Solution

1. Mold Structure Optimization  

The mold design was refined by improving the positioning mechanism and encapsulation method of the inserts. This ensures more uniform and complete coverage of the screws by the surrounding plastic, thereby minimizing the surface area exposed to humid environments.

2. Material Upgrade to AISI 304 Stainless Steel  

Superior Screw Material: We replaced the carbon steel with AISI 304 stainless steel, which has a self-repairing protective oxide layer that resists sweat and corrosion.

3. Selection of Enhanced Engineering Plastics  

Concurrently, we evaluated and implemented engineering plastics with superior chemical stability, lower moisture absorption, and reduced tendency to decompose into corrosive byproducts. This mitigates one of the key environmental contributors to metal degradation.

We thank our client for their valuable feedback. This solution underscores our commitment to continuous improvement and delivering durable, high-quality products.

Precision Advantages of a CNC Machining Center with Automatic Tool Changery

 Our new CNC machining center with an Automatic Tool Changer (ATC) is a significant upgrade.   Its key precision advantages are not from the tool change itself, but from how ATC enhances process stability and guarantees final part accuracy.

Here are the core benefits:

1.   Eliminates Human Error for Consistent Tool Setting

Manual vs. ATC: Manual tool changes introduce variability—inconsistent tightening force, potential contamination, or operator error—all leading to tool runout and inaccuracy.

ATC Advantage: The ATC performs every tool change with identical, programmed motions.   It ensures perfect, repeatable tool positioning in the spindle by consistently cleaning the taper, gripping, and locking each time.   This removes random human errors, guaranteeing superior tool-holding rigidity and minimal runout.

2.   Enables "Complete Machining in a Single Setup"

Manual Bottleneck: Complex parts requiring milling, drilling, and tapping must be interrupted for manual tool changes, introducing potential errors from machine thermal shifts or part stress relief.

ATC Advantage: The machine can automatically change tools and complete all operations in one continuous cycle without removing the part.   This is critical for precision because it:

Maintains a Single Datum: The workpiece remains fixed, avoiding cumulative errors from re-fixturing.

Guarantees Geometric Relationships: It reliably ensures high positional accuracy between features (holes, slots, surfaces) on a part.

3.   Ensures Batch Consistency and Process Stability

ATC Advantage: For batch production, ATC ensures the entire process, including tool changes, is perfectly repeatable from the first to the thousandth part.   This guarantees high consistency in dimensions and tolerances across the entire production run, which is difficult to achieve with manual intervention.

4.   Supports Optimized Machining Strategies

ATC Advantage: ATC allows for dedicated "roughing" and "finishing" tools.   The finishing tool remains sharp and unaffected by roughing wear, directly producing better surface finish and tighter tolerances.   It also enables in-process probing and automatic tool compensation for adaptive control.

In summary, the key precision advantages are:

High Repeatability: Consistent tool positioning.

Low Error Accumulation: "One setup" machining prevents error stacking.

High Process Stability: Removes human variables.

Superior Process Capability: Enables optimal finishing strategies.

This new machine will provide customers with more precise mold manufacturing services

Rotary Secondary Injection Molding: Characteristics and Applications

 Rotary secondary injection molding is an advanced manufacturing process that enables the production of integrated dual-material components in a single operation.  This technology combines two different plastic materials—typically a rigid substrate and a soft elastomer—into a seamless, high-quality product.

Process Overview

The process begins with the injection of the first material (usually rigid polymers like ABS, PC, or PP) into cavity A, forming the product's structural base.  The mold then rotates 180 degrees, aligning the substrate with cavity B. A second material (such as TPU, TPE, or silicone) is injected to encapsulate designated areas of the base component.  Finally, the completed part is ejected, ready for use without additional assembly.

Key Advantages

1.  Enhanced Product Quality: The immediate bonding between freshly molded materials ensures superior adhesion, while mechanical interlocking features prevent delamination.  This results in durable components with seamless transitions between materials.

2.  Increased Efficiency: By consolidating two manufacturing steps into one automated cycle, the process eliminates intermediate handling and significantly reduces production time.  This automation allows for higher output with minimal operator intervention.

3.  Design Flexibility: Engineers can create products combining multiple material properties—such as rigid structural elements with soft-touch surfaces—enabling innovative designs that improve both functionality and user experience.

Applications

This technology is widely employed across industries:

- Consumer electronics: Protective cases, wearable device bands

- Automotive: Steering wheels, control buttons

- Medical devices: Ergonomic instrument handles

- Household products: Tool grips, kitchenware handles

Economic Considerations

While requiring higher initial investment in specialized equipment and mold design, rotary secondary injection molding becomes cost-effective for high-volume production.  The reduction in assembly steps and improved product quality contribute to long-term manufacturing efficiency.

This advanced molding technique continues to gain popularity as manufacturers seek to create sophisticated products that combine multiple material properties while maintaining production efficiency and consistent quality.

CNMOULDINGs: Professional Two-Shot Overmolding Mold Manufacturer

 CNMOULDINGs is a high-tech enterprise specializing in the design, production, and machining of two-shot overmolding molds. With years of industry experience and advanced manufacturing technology, we are committed to providing high-quality, high-precision two-shot injection mold solutions for industries such as consumer electronics, medical devices, automotive parts, and home appliances.

Core Business: Two-Shot Overmolding Molds

Two-shot overmolding (also known as dual-material or multi-material molding) is an advanced injection molding process that combines two different plastics or colors in a single production cycle, enhancing product functionality, aesthetics, and durability. CNMOULDINGs excels in this field with the following advantages:

Precision Design & Engineering

Utilizes CAD/CAE/CAM software for mold structure optimization, ensuring stability and accuracy in injection molding.

Supports complex two-shot designs, including soft/hard material bonding, multi-color combinations, and transparent/opaque integrations.

High-Quality Materials & Processes

Uses premium mold steels (e.g., S136, 718H) with heat and surface treatments to extend mold lifespan.

Strict control of injection parameters to eliminate weld lines, air bubbles, or delamination.

Diverse Applications

Consumer Electronics: Phone buttons, earphone casings, wearable devices.

Automotive Parts: Dual-color buttons, seals, interior components.

Medical Devices: Non-slip grips, soft-touch housings.

Household Items: Toothbrush handles, tool grips.

Technical Advantages

Two-Shot Molding Machines: Compatible with rotary plate, core-back, and other two-shot molding methods.

Rapid Prototyping & Mass Production: Short lead time from design to trial molding, accelerating time-to-market.

Strict QC System: Ensures dimensional and functional accuracy via 3D scanning, CMM, and other inspection methods.

Service Commitment

CNMOULDINGs prioritizes customer needs, offering one-stop solutions:

Mold design consultation → Production & machining → Trial molding → Mass production support.

Flexible customization for both small batches and large-scale manufacturing.

Contact Us

For professional two-shot overmolding solutions, CNMOULDINGs is your trusted partner! Visit our website or contact us directly for technical details and case studies.

CNMOULDING: Professional Insert Molding Manufacturer – High-Precision, High-Strength Insert Molding Solutions

 CNMOULDING is a high-tech enterprise specializing in the design, manufacturing, and production of insert molding (Insert Molding) molds. We are committed to providing global customers with high-precision, high-stability insert molding solutions for applications in automotive, electronics, medical, home appliances, and industrial components.

With advanced machining equipment, extensive industry experience, and a strict quality control system, CNMOULDING has become a long-term partner for many renowned companies worldwide, offering one-stop services from mold development to mass production.

Key Advantages of Insert Molding

Insert molding is an efficient process where metal or non-metal inserts (such as nuts, screws, terminals, or sensors) are pre-placed into the mold and then encapsulated with plastic. Compared to traditional assembly methods, CNMOULDING’s insert molding technology offers the following benefits:

1. High-Strength Bonding: The plastic encapsulates the insert with high strength, ensuring superior pull-out force and torque resistance, thereby preventing any loosening or detachment.  

2. Cost Efficiency: By eliminating post-molding assembly processes, this method reduces labor costs and minimizes assembly errors, thus significantly enhancing production efficiency.  

3. High-Precision Molding: Precision-engineered molds guarantee accurate positioning of the insert and uniform encapsulation of the plastic, meeting stringent engineering requirements.  

4. Wide Insert Compatibility: This technology supports a variety of materials for inserts, including metals (such as copper, aluminum, and stainless steel) and non-metallic options, addressing diverse industry needs.  

5. Material Versatility: It is compatible with both thermoplastics (e.g., ABS, PC, PA, POM) and thermosetting plastics (e.g., phenolic resins), fulfilling various performance requirements across applications.  

CNMOULDING’s Core Competencies

1. Advanced Mold Design and Manufacturing  

CAD/CAM/CAE simulation is utilized to optimize the mold structure, ensuring stability and enhancing the accuracy of insert positioning.  

High-precision CNC machining, EDM (Electrical Discharge Machining), and mirror polishing are employed to guarantee mold durability and superior product surface quality.  

2. Mature Insert Molding Process  

Automated systems for insert placement improve production efficiency and maintain consistency in manufacturing processes.  

Rigorous process control over parameters such as temperature, pressure, and injection speed effectively prevents issues like insert misalignment and insufficient plastic filling.  

3. Rigorous Quality Inspection  

Advanced inspection methods, including 3D scanning, pull-out tests, torque tests, and others, ensure that the bonding strength of inserts complies with industry standards (ISO 9001, IATF 16949).  

4. Wide Industry Applications  

Automotive: Sensor housings, connectors, gear assemblies  

Electronics: PCB inserts, switch components, heat dissipation modules  

Medical Devices: Surgical instrument handles, disposable medical inserts  

Home Appliances: Buttons, fasteners, structural parts  

Why Choose CNMOULDING?

🔹 30+ Years of Experience – Successfully served 500+ global customers in insert molding.

🔹 Rapid Response – Efficient project support from mold design to mass production.

🔹 Cost Optimization – Process improvements reduce scrap rates and save costs.

🔹 Custom Solutions – Tailored services including multi-cavity molds, hot runner systems, and automated insert placement.

Contact Us

If you are looking for a reliable insert molding supplier, CNMOULDING is your ideal partner! Contact us for customized solutions, professional technical support, and high-quality service.

CNMOULDING: Professional Soft Rubber Product Solutions Provider

 As a company specializing in soft rubber product design, mold development, and manufacturing, CNMOULDING leverages extensive industry experience and technical expertise to provide one-stop soft rubber product solutions, including customized production using various materials such as silicone, TPU, and TPE.  

CNMOULDING’s Core Advantages  

one. Diverse Material Options to Meet Various Needs

We offer a wide range of soft rubber materials, including:  

Food-grade silicone (FDA/LFGB compliant, suitable for baby products and kitchenware)  

High-elasticity TPU (wear-resistant, tear-resistant, ideal for sports gear and industrial components)  

Eco-friendly TPE (recyclable, low hardness, perfect for medical devices and electronic accessories)  

Special-performance soft rubber (custom options for high-temperature resistance, flame retardancy, conductivity, etc.)  

two. Precision Mold Development Ensures Product Quality  

High-precision CNC machining and 3D printing mold flow analysis optimize mold structure  

Support for multi-cavity and stack mold designs to improve production efficiency  

Capable of producing ultra-thin soft rubber parts (as thin as 0.2mm)** to meet high-precision requirements  

three. Advanced Manufacturing Processes Guarantee Performance  

Liquid Silicone Rubber (LSR) Injection Molding—Ideal for high-precision medical and electronic components  

Solid Silicone Compression Molding—Suitable for high-temperature kitchenware and seals  

TPU/TPE Injection Molding—Used for anti-slip grips, sports protectors, etc.  

Overmolding (Two-Shot Molding)—Combines hard and soft rubber for enhanced functionality  

four. Strict Quality Control Complies with International Standards  

ISO 9001 certification ensures standardized production processes  

RoHS/REACH compliance testing meets export requirements  

Physical performance testing (tensile strength, tear resistance, temperature resistance, etc.)  

Why Choose CNMOULDING?

End-to-end support from design to mass production—DFM (Design for Manufacturability) analysis optimizes product structure  

Rapid prototyping and small-batch production—Shortens product development cycles  

Cost-optimized solutions—Material selection and process improvements reduce overall costs  

Global logistics support—Stable supply chain for markets in Europe, America, Asia, and beyond  

CNMOULDING—Your Trusted Soft Rubber Manufacturing Partner!

How to Address the Issue of Thin and Easily Broken Ejector Pins in Injection Molds

 1. Optimize the Ejection Process  

Adjust ejection parameters to minimize stress on delicate ejector pins.  

Reduce ejection speed: Excessively high ejection speeds generate significant impact forces, increasing the risk of breakage in thin ejector pins. A moderate reduction in speed can mitigate this risk.  

Implement multi-stage ejection: Utilize the multi-stage ejection capability of the injection molding machine. Initiate the first stage at a low speed and short stroke to release vacuum adhesion, followed by standard ejection in the second stage. This approach effectively reduces peak impact loads.  

Verify ejection stroke: Ensure the stroke is precisely calibrated to fully eject the part without over-extension, which may cause the ejector pin to lose guidance support and become unstable.  

Maintain proper lubrication: Regularly apply high-temperature mold release oil to the ejector pins to minimize friction between the pins and the mold core.

2. Revise Mold Design  

The most effective and long-term solution is to replace fragile, undersized thimbles with larger-diameter counterparts.  

This modification requires adjustments to the hole positions in both the mold core and the ejector plate. Although this involves higher initial costs, it provides a durable and reliable resolution.

3. Modify Ejection Methodology  

When spatial constraints prevent increasing the pin diameter, alternative ejection mechanisms should be considered.  

Use flat thimbles: In narrow regions such as rib areas, flat thimbles offer a greater cross-sectional area and superior resistance to bending compared to round thimbles.  

For boss columns with high shrinkage forces, employ stripper pins, which provide a broader and more uniform ejection surface.  

For deep cavities or thin-walled parts, consider air-assisted ejection systems. These introduce compressed air from within the cavity to disrupt vacuum formation, significantly reducing demolding resistance.  

Apply push plate ejection: For large, deep-container components, push plates offer full-surface contact, distributing ejection force evenly and minimizing localized stress compared to point-contact ejector pins.

4. Enhance Mold Structural Integrity  

Incorporate guide pillars: Install guide sleeves on the ejector plate to ensure precise alignment and smooth movement of the ejector system, thereby preventing lateral shear forces due to misalignment.  

Polish ejector pin bores: Inspect and refinish worn pin holes to reduce friction and improve operational smoothness.  

Inspect for and correct undercuts: Conduct a thorough mold inspection to identify any unintended undercuts that may contribute to excessive part retention force, and rectify them accordingly.

What Causes Corrosion in Metal Inserts within Plastic Products?

 Environmental Factors

Exposure to certain environments is the most common cause of corrosion.

Moisture/Humidity: The presence of water triggers the oxidation of iron (rust). In humid conditions, moisture condenses on the metal surface, initiating corrosion.

Chlorides: Exposure to salt (e.g., from coastal air, sweat, or deicing salts) drastically accelerates corrosion, causing severe "salt-induced rusting."

Acids/Alkalis: Contact with cleaning agents, sweat, or industrial chemicals can break down the metal's protective surface layer, increasing corrosion risk.

Insert-Specific Factors

The metal's inherent properties are critical.

Material: Carbon steel rusts easily unless protected. Some stainless steel grades (e.g., low-quality types) may still corrode in harsh environments.

Surface Coating: A lack of coating, or a poor-quality one (e.g., thin, porous plating like zinc or nickel), provides inadequate defense. Damage during handling also creates weak points for rust to start.

Design & Manufacturing Factors

The integration and assembly process plays a key role.

Residual Stress from Molding: The high heat of insert molding and subsequent cooling can create internal stress in the metal, making it more prone to "stress corrosion."

Over-Tightening during Assembly: Excessive force can strip protective coatings and create micro-cracks, offering a path for corrosion.

Galvanic Corrosion: If the insert contacts a different metal (e.g., an aluminum part) in a moist environment, an electrochemical reaction can rapidly corrode the less noble metal.

IV. Other Influences

Additional factors can contribute to the problem.

Plastic Properties: Some plastics (like PVC) can release acidic substances over time, which may slowly attack the metal.

Storage/Transport: Damp warehouses or inadequate packaging can expose products to moisture long before they reach the end user.

Summary of Mitigation Strategies

Material Selection: Choose appropriate corrosion-resistant alloys, such as 304 or 316 stainless steel, for the expected environment.

Surface Treatment: If using carbon steel, apply high-quality coatings like Dacromet or zinc phosphating, which are superior to standard electroplating.

Process Control: Optimize molding and assembly processes to minimize residual stress and avoid damaging the inserts.

Environmental Management: Control storage humidity and use protective packaging to limit exposure to moisture.

Overcoming Smart Bracelet Screw Corrosion: A Targeted Solution

 A smart bracelet we produced for a quality-focused Italian client recently faced a critical test: embedded metal screws began to rust during use. This issue, while seemingly small, compromised both the product's appearance and its long-term reliability.

Screw corrosion is a common challenge in wearables, typically resulting from a combination of factors:

Sweat Exposure: Frequent contact with skin exposes the screws to sweat, whose moisture and salts steadily corrode any weak points in the metal's protection.

Material Vulnerability: Previously used carbon steel screws with electroplated zinc were cost-effective, but the coating could be thin or easily damaged, allowing sweat to penetrate and cause rust.

Manufacturing Stress: The high heat of the molding process creates residual stress in the screws as the plastic cools, making the metal more prone to corrosion.

Implemented Solutions:

Improved Mold Design: We redesigned the mold to ensure the plastic encapsulates the screw more completely, minimizing its exposure to air and moisture.

Superior Screw Material: We replaced the carbon steel with AISI 304 stainless steel, which has a self-repairing protective oxide layer that resists sweat and corrosion.

Better Plastics: We switched to more stable, less moisture-absorbent engineering plastics to reduce the corrosive elements in the immediate environment.

We thank our client for their valuable feedback. This solution underscores our commitment to continuous improvement and delivering durable, high-quality products.

plastic bar handle

 

• Plastic Handle and Plastic Bar
• Price:2USD/SET
• Delivery Time within 30 days, 100K
• Product description: Cn-moulding has 10 years of experience produce plastics handle and plastic bar mold and parts in china. It through injection molding and ultrasonic welding technic

The development of the Chinese fitness equipment industry began in the 20th century in the late 1980s. With China’s accession to WTO and the success of Beijing’s bid for the development of the fitness equipment industry. Providing favorable conditions and opportunities for development, customer demand for plastic products, rapid growth.
Such as various types of plastic handle plastic bar.

China’s fitness equipment industry in the rapid development of a number of issues is increasingly apparent. Especially the lack of well-known brands in the international market, low value-added products. While compared with the international advanced level, many Chinese injection molds and plastic products manufacturing enterprises are still in the generic production stage. A lack of product development and technological innovation. In the consumer area, compared with Europe and other developed countries, fitness equipment products in household penetration and per capita consumption is still very low for fitness. Fitness equipment, plastic products in the Chinese market is still small.

Therefore, Chinese enterprises must seize the new injection mold development situation, increase scientific and technological innovation, and strive to improve the quality of plastic products, strengthening R & D capabilities and strengthen after-sales service. The only way to be invincible in the new situation.

CNMOULDING focus on all kinds of fitness equipment, plastic molds, and plastic products, we as supporting long-term supplier for many famous foreign companies supporting the production of sports equipment, all kinds of plastic molds and related plastic products If you need our help, please immediately contact our sales manager.

What is injection Moulding used for?

 

Plastic Injection Molding service

The process can produce precise complex plastic products action of a gram to more than a hundred
kilograms, in virtually any plastic material. The process starts with feeding small plastic beads into a
heated screw and barrel system that melts the plastic into a high–viscosity liquid. The screw then
forces the molten plastic into a closed mold that provides the shape, cooling, and solidification, and
finally ejects the part. China Injection molding is fast and can be economical. But because every part
needs its own costly injection molding tool, the process is economically viable only for mass production,
usually more than 10,000 parts.

China Injection molding tools take weeks to build. Often, design mistakes become apparent, requiring
time–consuming mold corrections. Multiple iterations may go from the producer to the tool builder until the final
part design and quality are achieved, increasing costs and product time to market.

What is injection Moulding used

Plastic Injection molding is a method of producing parts with a heat-melt able plastics material.

 This is done by the use of a plastic injection molding machine. The shape which is produced is controlled by
what is called a “mold china” The plastic injection molding machine has two basic parts; the injection unit,
which melts the plastic and then injects or moves it into the mold, and the clamping unit, which holds the
mold. The unit clamps the mold in a closed position during injection, opens the mold after cooling, and ejects the finished part.

 Materials  can be used in a process called china injection molding

 These are thermoplastics such as polystyrene, nylon, polypropylene, and polythene – this means when
they are heated and then pressured in a mould they can be formed into different shapes. China injection
molding unit seen opposite has been made in one piece using this process An animation of an injection
moulding process is shown below. Injection moldings count for a significant proportion of all plastics
products from micro parts to large components such as bumpers and wheelie bins.  Virtually all sectors
of manufacturing use injection molded parts – the flexibility in size and shape possible through the use
of this process have consistently extended the boundaries of design in plastics and enabled the significant
replacement of traditional materials thanks to light-weighting and design freedom.  The table below shows
the type of products that can be injection moulded but is by no means comprehensive.

Plastic Injection Molding service industry include following

 1,Assemblies

2,Consumer Products
 3,Containers
 4,Medical / Dental Disposable
 5,Electrical / Computer Parts
 6,Food & Beverage
 7,Insertion Molding
 8,Living Hinge

List products that have been manufactured through injection moulding. Reference article for china injection molding companies 

china plastic injection molding

 

 China plastic injection molding-tooling for injection molds

CNMOULDING is one of the few plastic injection mold makers in China that specialize in manufacturing cost-effective custom injection molding and custom design tooling in China for injection molded plastic parts, compression molds, overmolding, and molds for investment casting. Innovative custom design tooling solutions such as our CAD plastic injection mold design services in China. Our custom design tooling manufacturing in China. Tooling for export program ensures a low upfront cost, high-quality solution for our client’s custom design tooling projects.

Tooling and mold making in China is our preferred manufacturing method for our customers when the time will allow. We feel by offering custom design tooling in China. We are able to give our customers quality steel tools for the price they would pay for aluminum tools in the US or Europe. We can make molds and tools in China to run at our plastics facilities, or to ship to your location.

 

We offer custom design tooling for OEMs, end-users, injection-molded plastics shops. And injection mold makers at our engineering facilities in China. Our experienced engineers allow us to maintain the high quality of our injection mold makers’ design services while keeping costs low. We also work with many U.S. And European design firms producing tools for them and will not sell our design services to their customers.

CNMOULDING designs and manufactures its clients’ custom tools. Die’s and molds to their specifications, produce new molds from its customers’ CAD files, or reverse engineer existing parts. As one of the premier injection mold makers, we are very proficient at reverse engineering many types of parts. We have many different 3D design software platforms to adapt to our customers’ systems. Digital data files and computerized machining are used almost exclusively for the tooling of custom molds.

For small and extremely large parts, which can be manufactured specifically for small or dedicated long-run production molds, provide high-quality custom design tooling. CNMOULDING is one of the best custom design tooling manufacturers in China, specializing in die and tooling design and tooling for export. We can manufacture tools that are multi-cavity molds, unscrewing molds, closure molds, hot-runner molds, and stack molds.

Custom Tooling for Export

Custom tooling for export to the U.S. and other countries is becoming more popular. CNMOULDING builds a large portion of its custom design tools for export. Our clients have found that they can save 50-70% on tooling by having us manufacture the tools for them in China and export them to their facility, a local plastic shop, or our plastic injection molding facility. By making the molds in China customers can reduce their initial investment substantially, and allocate that revenue towards extra inventory if they choose.

CNMOULDING ensures 100% satisfaction with our tools. Detailed drawings are provided for customer approvals, and we always provide prototypes for first article approval prior to packaging and shipping the tools. Custom tools are also designed to fit in whatever injection molding equipment our customers or their suppliers might have. Those dimensions are obtained from our customers prior to finalizing pricing and drawings.
Send us your next custom tooling project for a free reference quote from our factory. We guarantee you will be impressed with the quality and savings!

CNMOULDING: Professional Soft Rubber Product Solutions Provider

 As a company specializing in soft rubber product design, mold development, and manufacturing, CNMOULDING leverages extensive industry experience and technical expertise to provide one-stop soft rubber product solutions, including customized production using various materials such as silicone, TPU, and TPE.  

CNMOULDING’s Core Advantages  

one. Diverse Material Options to Meet Various Needs

We offer a wide range of soft rubber materials, including:  

Food-grade silicone (FDA/LFGB compliant, suitable for baby products and kitchenware)  

High-elasticity TPU (wear-resistant, tear-resistant, ideal for sports gear and industrial components)  

Eco-friendly TPE (recyclable, low hardness, perfect for medical devices and electronic accessories)  

Special-performance soft rubber (custom options for high-temperature resistance, flame retardancy, conductivity, etc.)  

two. Precision Mold Development Ensures Product Quality  

High-precision CNC machining and 3D printing mold flow analysis optimize mold structure  

Support for multi-cavity and stack mold designs to improve production efficiency  

Capable of producing ultra-thin soft rubber parts (as thin as 0.2mm)** to meet high-precision requirements  

three. Advanced Manufacturing Processes Guarantee Performance  

Liquid Silicone Rubber (LSR) Injection Molding—Ideal for high-precision medical and electronic components  

Solid Silicone Compression Molding—Suitable for high-temperature kitchenware and seals  

TPU/TPE Injection Molding—Used for anti-slip grips, sports protectors, etc.  

Overmolding (Two-Shot Molding)—Combines hard and soft rubber for enhanced functionality  

four. Strict Quality Control Complies with International Standards  

ISO 9001 certification ensures standardized production processes  

RoHS/REACH compliance testing meets export requirements  

Physical performance testing (tensile strength, tear resistance, temperature resistance, etc.)  

Why Choose CNMOULDING?

End-to-end support from design to mass production—DFM (Design for Manufacturability) analysis optimizes product structure  

Rapid prototyping and small-batch production—Shortens product development cycles  

Cost-optimized solutions—Material selection and process improvements reduce overall costs  

Global logistics support—Stable supply chain for markets in Europe, America, Asia, and beyond  

Contact Us for Professional Soft Rubber Solutions!  

TEL: 86-21-52913487

FAX: 86-21-59907980

WhatsApp/Wechat: +8613061707408

Email: webmaster@cnmoulding.com  

CNMOULDING—Your Trusted Soft Rubber Manufacturing Partner!

CNMOULDING -- Professional TPE Injection Molding Solutions Provider

 CNMOULDING is a high-tech enterprise specializing in TPE (thermoplastic elastomer) injection molding, committed to offering customers comprehensive one-stop services ranging from material development, mold design, injection molding to finished product assembly. Equipped with advanced production equipment, a stringent quality control system, and extensive industry expertise, we have established long-term partnerships with numerous internationally renowned brands.  

Core Advantages  

One. Advanced TPE Injection Molding Technology  

    Utilizing all-electric injection molding machines and high-precision molds to ensure consistent product dimensions and smooth surface finishes.  

   Supporting Overmolding and 2K Molding processes, achieving robust bonding between TPE and materials such as PP, ABS, and PC.  

   Customizable TPE materials with varying hardness levels (Shore A 0-100), color options, transparency, and specialized properties (e.g., flame retardancy, UV resistance, oil resistance, etc.).  

Two. Rigorous Quality Control  

   Certified under the ISO 9001 quality management system to ensure standardized production processes.  

   Conducting comprehensive testing throughout the entire production cycle, including physical property evaluations (tensile strength, tear resistance, rebound resilience, etc.) and environmental compliance assessments (ROHS, REACH, FDA).  

   Providing PPAP (Production Part Approval Process) and IQC/OQC quality control measures to meet the stringent requirements of industries such as automotive and medical.  

Three. Swift Response and Flexible Production 

   Capable of supporting small-scale trial production to large-scale mass production, adapting flexibly to customer demands.  

   Featuring an in-house mold workshop that offers mold design, development, and optimization services to expedite delivery timelines.  

   A fully integrated supply chain ensures a stable supply of raw materials while minimizing production costs.  

Application Fields of TPE Injection Molding  

Automotive Components: Sealing strips, dust covers, interior components.  

Electronics and Appliances: Cable sheaths, headphone housings, keyboard pads.  

Daily Consumer Goods: Toothbrush handles, kitchenware grips, toys.  

Medical Supplies: Breathing masks, infusion tubes, medical gaskets.  

Why Choose CNMOULDING?  

Professional Team: With over 10 years of experience in TPE injection molding, our team provides expert advice on material selection and process optimization.  

High Cost-Effectiveness: By optimizing production processes and reducing defect rates, we assist customers in effectively controlling costs.  

Full-Service Solution: From design support and mold development to mass production delivery and after-sales tracking, we offer a seamless and worry-free experience.  

Global Supply Capability: Our products are exported to international markets, including Europe, the United States, Japan, and South Korea, adhering to global environmental protection and safety standards.