NowOn behalf of the manufacturing industry precision "molding magician"

• 2025-06-29

NowOn behalf of the manufacturing industry precision "molding magician"

In today's highly industrialized era, from the palm-sized smart watch shell, to the complex dashboard components inside the car, to the life-saving precision consumables in the medical field, plastic products are deeply integrated into every corner of life and production with their diversified forms. Behind all this, injection molding Mold is undoubtedly the most critical "hero behind the scenes". With its precise process and efficient production capacity, it has become an indispensable core technology and equipment for the Now-generation manufacturing industry, and is known as the "invisible" of industrial production. pusher ".

Definition and Principle of 1. Injection Mold

Injection mold is a special tool that converts plastic raw materials into products with fixed shape and size through a specific process according to the design requirements of plastic products. Its working principle is deeply dependent on the thermoplastic properties of plastics, and the entire production process is like a sophisticated "industrial ballet ":

1.melt plasticizing:

After the plastic particles enter the barrel of the injection molding machine, they undergo a transition from solid state to viscous flow state under the dual action of the heating device and the rotation of the screw. With common polypropylene (PP) For example, the temperature needs to be accurately controlled160 - 220℃ range, so that the plastic fully melted, laying the foundation for subsequent molding.

2.high pressure injection:

Screw up100-150MPaThe molten plastic is injected into the mold cavity at high speed. This high pressure can ensure that the plastic can quickly fill every tiny corner of the mold. For automobile bumper molds with complex structures, high-speed injection can effectively avoid the problem of insufficient filling.

3.cooling setting:

The cooling system in the mold works quickly, by circulating cooling water (the water temperature is usually controlled20 - 30℃) Take away the heat of the plastic and make it cool and solidify in the cavity. Cooling time directly affects production efficiency and product quality, such as mobile phone shell mold cooling time generally need to be precisely controlled in.15 - 30Seconds.

4.Demoulding and picking up:

The mold is opened along the parting surface, and the ejection system (such as push rod, push plate) pushes out the molded product smoothly. In order to prevent product surface damage, the ejection speed and force need to be precisely adjusted. .

With this cyclical process, injection molding Mold can produce thousands of plastic products with high efficiency and consistency, to meet the needs of Now generation industrial mass production.

Core structure of 2. injection mould

The structure of the injection molded Mold is a subtle example of industrial design, with six core systems working together:

1. Molded parts system

Core role: directly determines the shape, size and surface quality of plastic products, is Mold"Soul"In part.

Key components:

Core, used to form the inner surface of the product, such as the inner wall of the plastic cup, the inner hole of the pipe, etc.

Cavity the outer surface of the molded product, such as the shape of the mobile phone shell, the outline of the toy, etc.

Insertions, for complex shapes or wear-prone areas, can be processed and replaced separately, such as fine in the mold.LOGOpart, thread structure, etc.

Design points: need to accurately match the requirements of product drawings, while considering the demoulding angle, surface roughness and other details, to avoid demoulding difficulties or product appearance defects.

2.gating system

Core function: guide the molten plastic from the injection molding machine nozzle into the Mold cavity, control the flow rate of plastic, pressure and filling sequence.

Key components:

The main flow channel, connecting the injection molding machine nozzle and the shunt channel, is conical, which is convenient for the flow of plastic melt and the removal of the main flow channel condensate during demoulding.

The shunt channel distributes the plastic of the main channel to each cavity, and designs its size and shape according to the number and layout of the cavity.

Gate, the last channel of plastic into the cavity, directly affects the filling effect and product quality, common types are side gate, point gate, latent gate, etc.

The cold material cavity collects the cold material at the beginning of injection molding to prevent it from entering the cavity and causing Now cold material spots and material shortage.

3.guidance and positioning system

Core function: to ensure that the moving mold and the fixed mold are accurately aligned during the mold clamping process, and to avoid product flash, size deviation and even Mold damage caused by misalignment.

Key components:

Guide pillar and guide sleeve, the guide pillar is installed on the moving mold or fixed mold, and the guide sleeve is installed on the corresponding fixed mold or moving mold. When the mold is closed, the guide pillar is inserted into the guide sleeve to play a guiding role.

Positioning cone, in high-precision Mold, the auxiliary guide column guide sleeve further improves the positioning accuracy and enhances the stability of Mold mold clamping.

4.ejection system

Core function: The molded plastic products are pushed out from the Mold cavity or core to complete the product demoulding.

Key components:

The thimble (push rod) directly contacts the plastic parts and exerts the pushing force. There are common round thimble, flat thimble, etc. It is necessary to select the appropriate type and layout according to the product structure.

Thimble plate, connecting the thimble, transmitting the thrust of the ejection device of the injection molding machine.

The reset mechanism, such as the reset spring and the reset rod, ensures the accurate reset of the thimble plate before the mold is closed, and avoids the collision between the thimble and the mold core.

5.Cooling system

Core role: through the circulating coolant (usually water) to take away the Mold heat, control the Mold temperature, accelerate the plastic cooling solidification, improve production efficiency, while ensuring product dimensional accuracy and surface quality.

Design points: design the cooling channel layout according to the Mold structure and product shape to ensure uniform flow of coolant and avoid local overheating or overcooling; Reasonably control the diameter, spacing and flow direction of the water channels to prevent Now cooling dead corners.

6.Exhaust system

Core function: discharge the air in the medium cavity during the injection molding process and the gas generated by the thermal decomposition of the plastic to prevent the product from Now pores, air lines, scorching and other defects.

Real Now way:

The exhaust groove is usually set at the parting surface, the end of the melt flow or the depth of the cavity, and the depth of the exhaust groove is generally controlled0.02 - 0.05mmAvoid plastic spills.

Use matching clearance, Use the tiny gap between the thimble and the pin hole, the slider and the chute and other components for exhaust.

Chair mold Manufacturer in China (jfmoulds.com)

Classification system of 3. injection mould

Injection Molding can be carefully classified according to different dimensions, and each type is aimed at specific production needs:

1.Classification by molding material

-Thermoplastic Mold: suitable for polyethylene (PE), polystyrene (PS) and other materials, such molds account for the total market.80%Above. toPEMaterials, for example, have a wide range of molding temperatures (130 - 180℃),Mold design should focus on cooling efficiency.

-Thermosetting plastic Mold: used for phenolic resin, epoxy resin and other materials processing. Plastics undergo irreversible chemical reaction curing in Mold. Mold needs to have higher high temperature resistance (working temperature can reach180 - 220℃) and corrosion resistance.

2.Classification by number of cavities

-Single cavity Mold: Commonly used in the sample trial production of new product development stage, or the production of high value-added, customized precision products, such as jewelry box lining Mold.

-Multi-cavity Mold: widely used in the field of daily necessities production, such as disposable tableware Mold, commonly8Cavity16cavity even64The cavity design can greatly improve production efficiency and reduce the cost of a single piece.

3.Classification by structural features

-Two-plate Mold: simple structure, low manufacturing cost, suitable for products with simple structure, such as plastic basin Mold, the parting surface design directly affects the product demoulding effect.

-Three-plate Mold: adding a runner plate can Nowgating the automatic separation of system condensate and products. it is often used for precision products fed by point gates, such as electronic chip packaging Mold.

-Hot runner Mold: The heating device keeps the molding system plastic in a molten state, which can save20% - 50%It is widely used in the production of automotive interior parts, but its system maintenance cost is high.

4. injection mold design and manufacturing process

1.Design stage: An iterative process based on innovation and optimization

Injection Mold design is a complex process that integrates experience and technology. Its core steps and innovation directions are as follows:

1.Demand docking and feasibility analysis

-At least with customers.3More than the depth of communication, with the help3DScanning technology to obtain the raw data of the product, to clarify the functional requirements of the product (e. g. medical device sealing requirements), appearance requirements (e. g. high-gloss surface treatment), dimensional tolerance standards (e. g. mobile phone shell.0.05mmof the accuracy requirements).

-ApplicationDFM(Manufacturing-oriented design) software to analyze the structural complexity of plastic products, simulate potential problems in the Mold manufacturing process, and determine technical feasibility and cost-effectiveness. For example, for products with an inverted structure, the lateral core-pulling mechanism needs to be planned in advance.

2.innovative structural design

-Application the modular design concept, the Mold is decomposed into replaceable functional units. Such as in the car Mold, the complex door Mold split into the main module, decorative strip module and buckle module, enhance Mold versatility and maintenance convenience.

-Explore new demoulding mechanisms, such as hydraulic demoulding (suitable for large thin-walled products), pneumatic demoulding (suitable for precision small products), to solve the demoulding problem of complex structural products. A new energy vehicle battery box Mold adopts hydraulic demoulding technology, which successfully realized the efficient demoulding of Now deep cavity structure products.

3.simulation-driven optimization

-UseMoldflow,AutoCAD MoldSuch as professional analysis software, more20parameters, including the flow front of the plastic melt, pressure distribution, temperature field changes, holding pressure process, cooling process, etc.

-Through simulation analysis, predict and eliminate potential molding defects (such as sink marks, warpage, weld lines). For example, by adjusting the gate location and number, the warpage of a laptop case is changed from0.8mmReduced0.2mmWithin.

4.Collaborative Design Review

-Organize the design, manufacturing and production departments to carry out joint review and Application virtual Now (VR) Mold assembly simulation with technology to ensure the manufacturability of the design scheme. During the review process, at least10The above amendments are proposed.

-Introduce customer participation in design reviews, collect feedback in real time through an online collaboration platform, and conduct at least3More than the design optimization.

2.Manufacturing stage

1.Material selection: According to the requirements of Mold, from H13Mold steel (commonly used in ordinary Mold, hardness HRC48-52),NAK80 pre-hardened steel (suitable for high-gloss Mold, hardness HRC38-41) to hard alloy (for precision Mold) and other materials to choose. For example, the production of optical lens Mold, will choose high hardness, wear resistance of tungsten steel material.

2.precision machining:

-Traditional processing: the use of high-precision CNC lathes (machining accuracy up to ±0.001mm), five-axis linkage machining center for turning, milling, grinding and other processing; Use EDM (EDM) Technology to process complex cavities and cores, and its machining accuracy can reach0.01mm.

-Advanced technology: Application3Dprinting technology (suchSLMSelective laser melting technology) to create a conformal cooling channel mold, which can improve cooling efficiency.30% - 50%; Using high-speed milling technology (spindle speed up40000r/min) Mold surface finishing to reduce polishing process.

3.Assembly and commissioning: Strictly control the assembly accuracy and Application the three-coordinate measuring instrument (CMM1) Each component shall be inspected to ensure that the fitting tolerance is within the design range. At least on the injection molding machine5After each test, the Mold temperature, injection pressure, holding time and other parameters are adjusted and optimized until qualified products are produced.

Five, injection molding Mold industry applications

   1. Automobile manufacturing industry

Application: automotive interior and exterior parts, functional parts and other super70%The plastic parts rely on injection molding production. Such as instrument panels, door panels, bumpers, air conditioning outlets, car light housings, engine intake manifolds, fuel tanks, etc.

Industry demand characteristics: to meet the requirements of high strength, weather resistance, lightweight, precision error control in.0.03mmIn addition, Mold has to withstand more than one million injection molding cycles, which requires extremely high quality of Mold steel, Cooling system efficiency and surface treatment process. For example, the bumper Mold needs to take into account the complex shape and rapid cooling to improve the production rhythm.

         2.3CElectronic industry

Application scope: mobile phone, tablet PC shell, laptop keyboard, charger shell, earphone shell, smart watch strap and other precision plastic parts.

Industry demand characteristics: the pursuit of extreme thinness, high precision (tolerance.0.01mm) and high finish, often need in-mold injection (IMD), double-color injection molding and other complex processes realize Now appearance texture, multi-color integrated molding. If the mobile phone shell Mold needs to be matched with nano-scale polishing technology to meet the needs of mirror effect, and the product iteration is fast, the Mold development cycle is required to be compressed30Within days.

        3.Home appliance industry

Application: refrigerator liner, washing machine pulsator, air conditioning shell, TV frame, fan blades, microwave oven turntable, etc.

Industry demand characteristics: focus on Mold production efficiency and cost control, often using multi-cavity Mold (e. g.8Cavity16cavity) to increase production; some home appliance components need to meet food contact safety standards (such as small kitchen appliances), high environmental protection requirements for Mold materials; at the same time need to take into account personalized appearance design, such as curved surface modeling, imitation wood grain texture, etc.

          4.Medical Device Industry

Applications: syringes, infusion set components, medical consumables packaging, medical equipment shell, disposable medical equipment (such as blood collection needle holder, test reagent card shell), etc.

Industry demand characteristics: the implementation of strict medical device production quality management practices (GMP), the mold needs to be made of food grade stainless steel material, surface roughnessRa≤0.4μmTo ensure that there is no acute angle and no dead angle to meet the sterilization requirements; Some precision components (such as the shell of the heart stent conveyor) need to reach micron-level accuracy, and the production process needs to be traceable throughout.

          5.Packaging Industry

Application: plastic bottle, plastic box, bottle cap, blister packaging, cosmetic container, etc.

Industry demand characteristics: focus on Mold's high-speed molding and mass production capacity, such as mineral water bottle cap Mold single-mode cavity number can reach.128above the cavity, the production cycle only needs3 - 5Seconds; Packaging Mold often needs to be matched with special processes, such as the anti-theft ring structure of the bottle cap Mold, the frosted surface treatment of cosmetic bottles, etc. At the same time, it is necessary to meet the functional requirements of different products such as sealing and bearing.

          6.Toys & Stationery Industry

Application: plastic toys (such as building blocks, dolls, educational toys), stationery (such as stationery boxes, plastic ruler), sports equipment accessories (such as racket handle, fitness equipment shell), etc.

Industry demand characteristics: emphasize Mold's creative design and rapid response ability, need to support complex modeling, multi-color splicing, movable joints and other structures; Sensitive to Mold cost, economic Mold steel or aluminum Mold is often used to reduce development costs; At the same time, it must meet toy safety standards (suchEN71,ASTM F963), ensure that there is no sharp angle and no risk of small parts falling off.

         7.Building materials industry

Application range: plastic pipe fittings (suchPVCWater pipes,PPRjoints), door and window sealing strips, plastic profiles (such as skirting lines, decorative lines), sanitary ware accessories, etc.

Industry demand characteristics: Mold is required to have high wear resistance and adapt to long-term continuous production; Some building materials products need to meet the characteristics of flame retardant, anti-aging and high strength. For example, outdoor plastic profiles Mold need to be matched with weather-resistant materials. Mold for large pipes needs to solve technical difficulties such as uniform distribution of melt and setting of cooling to ensure uniformity of roundness and wall thickness of pipes.

six,MoldIndustry Development

1.High precisionWith the development of semiconductor packaging, microfluidic chips and other fields, Mold processing accuracy will move towards nanoscale. For example, Mold, which is used to make microlens arrays, needs to have a surface roughnessRa≤0.1nmProcessing equipment will be upgraded from traditional machine tools to advanced technologies such as electron beam processing and ion beam processing.

2.Intelligent:

Introduce IoT sensors to monitor Mold temperature, pressure, and wear in real time, predict Mold life through big data analysis, and realize Now preventive maintenance.

3.Green manufacturing:

Development of recyclable Mold materials, such as degradable Mold steel coatings; promotion of Mold remanufacturing technology to increase the reuse rate of waste Mold60%Above.

Optimization of Mold design, the use of in-mold assembly technology to reduce the subsequent assembly process, reduce energy consumption.

4.Multi-function integration: Future Mold will integrate injection molding, welding, assembly and other functions. For example, the intelligent door lock Mold developed by an enterprise can be embedded in the chip and circuit board simultaneously in the injection molding process, and the real Now product is integrated and molded, thus improving the production efficiency.40%.

From simple plastic containers to complex industrial parts, injection molding Mold has always been constantly innovative technology and excellence in the process, to promote the development of the Now generation manufacturing industry. In the era of intelligent manufacturing and green production, injection molding Mold will continue to break through the technical boundaries, to provide more efficient, more sophisticated, more environmentally friendly molding solutions for various industries, writing a new chapter in industrial manufacturing.

Storage basket mold Manufacturer in China (jfmoulds.com)