Manufacture

Injection molded conical positioning block Injection molding conical locators are key components for ensuring mold clamping accuracy. They are widely used in injection molds requiring high precision, especially large molds, multi-cavity molds, and molds with complex lateral core-pulling mechanisms. Compared to traditional flat positioning or guide pin and guide sleeve positioning, conical locators achieve precise positioning through the use ofMore

Pay attention to several process conditions that affect injection molding quality In injection molding, the setting and control of process conditions directly determine the quality of plastic parts. Even minor parameter fluctuations can lead to defects such as material shortages, flash, and warpage. Numerous process conditions influence injection molding quality, with injection pressure, melt temperature, mold temperature, holding time, andMore

General regulations for design and drawing of injection molds Injection mold design drawings are crucial technical documents for mold design and manufacturing. They embody mold design concepts and serve as the foundation for mold processing, assembly, inspection, and maintenance. To ensure the standardization, readability, and consistency of mold drawings, injection mold design drawings must adhere to a series of generalMore

Basis for selecting materials for injection mold parts The selection of materials for injection mold components is a critical step in mold design and manufacturing, directly impacting mold life, molding accuracy, production costs, and part quality. Different mold components are subject to varying loads, temperatures, friction, and other conditions during operation, necessitating the selection of appropriate materials based on theirMore

The inclined ejector mechanism of an injection mold is a crucial device for removing molded parts from undercuts or recesses. It is widely used in the molding of parts with complex structures such as internal bosses and grooves. When undercuts are present, traditional straight ejector mechanisms are unable to eject the part vertically, and forced ejection can cause deformation orMore

Types of Injection Molds Injection molds are the core equipment of injection molding production and can be divided into various types according to different classification standards. Each type of mold has its own unique structural characteristics and application range. Understanding the types of injection molds can help you select the appropriate mold based on factors such as the structure, material,More

Secondary demoulding mechanism of injection mold The secondary demolding mechanism of an injection mold is a key device for solving the demolding challenges of complex plastic parts. When a part’s unique shape (such as a deep cavity, undercut, or boss) prevents smooth removal during primary demolding or is prone to deformation or damage during removal, the secondary demolding mechanism appliesMore

Advantages of using small gate in injection mold The design of the gate in an injection mold has a significant impact on part quality, production efficiency, and mold costs. Small gates, a common type of gate, offer significant advantages in many injection molding scenarios. Small gates typically have a smaller cross-sectional area. Their dimensions depend on the part size andMore

Solution to the problem of severe shrinkage at the column position on the outer surface of the injection molded part Shrinkage at the pillar position on the outer surface of injection molded parts is a common appearance defect in production. It manifests as depressions and shrinkage pits on the outer surface corresponding to the pillar position. This not only affectsMore

Changes in cavity pressure during injection molding The change in cavity pressure during the injection molding process is a key parameter reflecting the melt filling, holding, and cooling processes within the cavity, directly impacting the density, dimensional accuracy, mechanical properties, and appearance quality of the plastic part. Cavity pressure refers to the pressure exerted on the cavity walls by theMore

Injection molding product testing and inspection Injection molding product testing and inspection is a critical step in ensuring that plastic part quality meets design requirements and application standards. This process runs throughout the entire production process, including incoming raw material inspection, in-process testing, and finished product inspection. Scientific and rational testing methods can promptly identify defects and quality risks inMore

The key component of the injection device – the nozzle The nozzle is the connecting component between the injection unit and the mold, located at the front end of the barrel. Its primary function is to smoothly and accurately inject the plasticized melt from the barrel into the mold cavity and prevent melt backflow during the injection and pressure-holding phases.More

Typical structure of injection device The injection unit is a core component of an injection molding machine. Its primary function is to heat and plasticize the plastic raw material into a molten state and then inject the melt into the mold cavity at a specific pressure and speed. The typical structure of an injection unit generally consists of a feedingMore

Injection time is a crucial parameter in the injection molding process. It refers to the time it takes for the melt to fill the mold cavity from the start of injection, directly affecting the quality of the plastic part, production efficiency, and raw material consumption. Properly setting the injection time ensures uniform filling of the melt within the mold cavity,More

Unstable product dimensions and solutions Part dimensional instability is a common quality issue in injection molding production. This occurs when the dimensions of plastic parts within or across batches fluctuate beyond the permitted range, impacting product assembly precision and performance, and in severe cases, even causing the entire batch to be scrapped. The causes of part dimensional instability are complexMore

Injection molding needle valve hot nozzle system The injection molding needle valve hot nozzle system is a high-precision injection molding equipment component primarily used for molding multi-cavity molds or large plastic parts. It controls the injection and stopping of the melt through the opening and closing of the needle valve, achieving precise control of the gating system. Compared to traditionalMore

Add glue (material) to the air-trapping area during injection molding Air entrapment is a common and challenging problem during the injection molding process. This occurs when air or volatiles within the mold cavity cannot be expelled promptly as the melt fills the mold cavity. Instead, they are trapped within the mold or in corners, leading to defects such as burning,More

Demolding of the fixed mold driven by the movable mold In traditional injection mold structures, an ejector mechanism is typically installed on the movable mold side to release the plastic part. However, demolding from the fixed mold is relatively special. Demolding from the fixed mold driven by the movable mold is an innovative demolding method suitable for parts with specificMore

Several key process parameters affecting the strength of injection molded parts The strength of injection molded parts is a key indicator of their performance, directly impacting product reliability and service life. Process parameter settings largely determine part strength. During the injection molding process, process conditions during melt flow, cooling, and solidification affect the part’s internal structure, such as molecular orientation,More

Secondary demoulding is used because the plastic parts need to be forced to demould In the field of injection molding, some plastic parts have special structures that make it difficult to remove them smoothly by conventional one-time demolding. In this case, the secondary demolding process becomes a key solution. Forced demolding is usually suitable for cases where the plastic partsMore

The influence of some color matching pigments on the strength of injection molded parts Color pigments are key auxiliary materials for adjusting the appearance of plastic parts during injection molding. However, their addition not only alters color but can also affect the mechanical properties of plastic parts through physical or chemical interactions. The chemical composition, particle size distribution, and dispersionMore

Hydraulic cylinder joint and piston stroke design Hydraulic cylinder joints and piston stroke are key components of hydraulic core pulling systems, directly impacting the reliability of oil circuits and the precision of core pulling movements. Joint design must balance sealing performance and connection strength, while stroke design must balance core pulling requirements with movement safety. Optimizing both is fundamental toMore

Hydraulic core pullers are a crucial mechanism for complex lateral core pulling in injection molds. Their advantages, including high core pulling force, controllable stroke, and smooth movement, make them widely used in large plastic parts or complex core pulling scenarios. However, their design requires coordination between the hydraulic system and the mold structure. Failure to carefully consider these factors canMore

Injection mold and solution Injection mold damage, also known as mold crush, is a common and serious defect in injection molding production. It occurs when, for some reason, the movable mold and fixed mold, or mold components, come into abnormal contact during the mold closing or injection process. This damages the mold surface or damages components. It can also leadMore

Venting of the cavity on the parting surface Venting at the parting surface is a critical step in ensuring part quality during injection molding. Its purpose is to promptly expel air and gases generated by melt decomposition from the cavity during melt filling, preventing defects such as bubbles, burning, material shortages, and weld marks in the molded part caused byMore

Cooling circuit for injection molding cavity The cooling circuit of the injection molding cavity is a core component of the mold cooling system, and its design rationality directly affects the molding cycle, dimensional accuracy, and surface quality of the plastic part. During the injection molding process, the melt releases a large amount of heat after entering the mold cavity. ThisMore

Injection molding inclined slider side core pulling mechanism The lateral core-pulling mechanism for injection molding, featuring an inclined slider, combines the features of an inclined top and a slider. It is suitable for use in plastic parts with internal or external undercuts (such as oblique side holes and inclined bosses). It achieves this by utilizing the oblique motion of theMore

Injection molding sloping top base design The injection molding lift base is a crucial component of the lift mechanism. Its primary function is to support the lift rod, guide its trajectory, and transmit the push plate’s driving force to it. Therefore, the rationality of the lift base’s design directly impacts the mechanism’s operational stability and core-pulling accuracy. The design ofMore

Injection molding inclined top, slider and hydraulic arc core pulling In injection molds, lifters, sliders, and hydraulic arc core pulling mechanisms are crucial for handling complex part structures (such as undercuts, side holes, and curved protrusions). Each has its own unique operating principles and application scenarios, and together they ensure the smooth demolding of complex parts. The lifter mechanism primarilyMore

Injection molded insert exhaust Venting of injection molding inserts is a crucial step in ensuring part quality during the injection molding process. Inserts, as metal or non-metal parts embedded in the mold, are used to create a specific part structure or enhance local mold strength. However, their presence can make it difficult for gases within the mold cavity to escape.More

Injection Molding Maintenance and Care Planning The maintenance and servicing of injection molding equipment is an important measure to ensure smooth injection molding production, improve production efficiency, and extend the service life of the equipment. Developing a scientific and reasonable maintenance and servicing plan is the key to ensuring that maintenance and servicing work is carried out in an orderlyMore

The injection molding demolding system is a key mechanism in the injection mold used to separate the formed plastic part from the cavity or core. It comes in a variety of forms and must be selected based on factors such as the part’s structure, material, and shape to ensure smooth demolding without compromising quality. Common injection molding demolding systems includeMore

Injection molding push block demoulding mechanism The injection molding push-block ejection mechanism utilizes a push block to eject the entire part from the mold cavity. Suitable for large, flat, curved, or complex-shaped parts, it features a large ejection area, evenly distributed force on the part, and a low risk of deformation or ejection marks. It plays a vital role inMore

Injection molding push tube demoulding mechanism The injection molding push-tube demolding mechanism is a demolding device suitable for cylindrical, annular, or center-hole plastic parts. It smoothly ejects the plastic part from the core by moving the push tube along the core axis. It offers advantages such as a large ejection area, uniform force distribution, and resistance to deformation. It isMore

Precautions for ejection of injection molding push rod Ejection by push rod is the most basic and commonly used method for mold release in injection molding. Its ejection effect is directly related to the integrity and surface quality of the plastic part, so many details must be paid attention to in actual application. The core of push rod ejection isMore

Injection molding push rod, flat push rod demoulding matters needing attention Injection molding push rods and flat push rods are important components in the mold release mechanism, each suitable for demolding plastic parts with different structures. The rationality of their design and use directly affects the demolding effect and surface quality of the plastic part, so many considerations are requiredMore

Injection molded breathable steel properties Injection molding breathable steel is a new mold material. Its unique porous structure and excellent breathability make it a key component in solving injection mold venting issues. It is widely used in the production of precision injection molding and complex plastic parts. Breathable steel, primarily composed of stainless steel, is manufactured through a specialized powderMore

Injection molding of transparent plastics Due to their excellent light transmittance and aesthetics, transparent plastics are widely used in electronics, medical devices, daily necessities, and other fields. However, their injection molding process differs significantly from that of ordinary plastics, placing higher demands on the production environment, equipment precision, and process parameter control. The core characteristic of transparent plastics is lightMore

Injection molding through hole into blind hole and solution In injection molding, through-hole-to-blind-hole refers to a hole structure originally designed to be through that becomes a blind hole with a closed bottom after the plastic part is molded. This defect not only affects the assembly performance and functional realization of the plastic part, but may also cause subsequent processing stepsMore

Injection mold adjustment device The injection molding mold adjustment device is the core component of the injection molding machine that realizes mold closing, locking, and adjusting mold thickness. Its performance directly affects the molding accuracy of plastic parts, production efficiency, and the operating stability of the equipment. The main functions of the mold adjustment device include: driving the movable platenMore

The mold transparency method is an intuitive and efficient technique for adjusting injection molding machines. Its core principle involves creating a simulated mold using transparent materials (such as acrylic or transparent resin sheets), or modifying key areas of an existing mold to be transparent. This allows operators to observe the melt flow, filling process, pressure distribution, and cooling status withinMore

Increasing the screw speed during plasticization can also improve the gas mark defect of PVC During the PVC (polyvinyl chloride) injection molding process, gas streaks are a common quality issue. These defects manifest as silvery or cloud-like streaks on the surface of the plasticized part, affecting not only the part’s appearance but also potentially degrading its mechanical properties. Gas streaksMore

Installation method of injection lock module The injection molding lock module is a crucial component of the injection molding machine. The quality of its installation directly impacts the machine’s operational accuracy and production safety, so it must be installed strictly in accordance with standard procedures. Before installation, the lock module must be thoroughly inspected to check for external damage, theMore

Polymers in plastics The core reason plastics exhibit such diverse properties lies in their polymers. Polymers are the building blocks of plastics, possessing unique molecular structures and performance characteristics. Polymers, also known as high-molecular compounds, are macromolecular chains composed of numerous identical or different monomers linked by covalent bonds. Their molecular weights typically range from tens of thousands to hundredsMore

Changes in plastic during injection molding During the injection molding process, plastics undergo a complex series of physical and chemical changes that directly impact the quality and performance of the molded part. The first stage is the plasticization phase in the barrel. After solid plastic particles are added, they are propelled forward by the rotation of the screw. Simultaneously, theyMore

Thermal diffusivity of plastics and corresponding mold temperature The thermal diffusivity of plastics is an important parameter for measuring their heat transfer capacity. It indicates how quickly a plastic transfers heat under a temperature gradient; a larger value indicates better heat transfer performance. The thermal diffusivity is closely related to factors such as the plastic’s composition, structure, and density. DifferentMore

Testing and selection of plastics Testing plastics is a key step in ensuring their quality and applicability, and covers tests of physical properties, chemical properties, mechanical properties, and other aspects. Physical property testing includes the determination of indicators such as density, melting point, and water absorption. These data can help determine whether the plastic meets the requirements for use inMore

Plastic composition and formulation Plastic is a polymer material composed of multiple components, primarily synthetic resins, along with various additives. These components work together to give plastics their diverse properties and uses. Synthetic resins are the plastic’s matrix, determining their basic properties, such as plasticity, strength, and heat resistance. Common synthetic resins include polyethylene, polypropylene, polyvinyl chloride, and polystyrene. DifferentMore

Demolding angle of plastic parts The draft angle of a plastic part is a crucial parameter in the plastic molding process, directly impacting part quality and production efficiency. The draft angle refers to the angle between the sidewall of the plastic part and the mold cavity wall. Its primary function is to ensure smooth removal of the part from theMore

In modern manufacturing, the use of engineering plastics for plastic parts has become a widespread trend, driven by their exceptional performance. Engineering plastics possess high strength and toughness, enabling them to maintain a stable structural form even under complex operating conditions. For example, in automotive manufacturing, many key components, such as instrument panel frames and door trim panels, are madeMore

Excessive noise during plasticization and its solution Plasticization is a critical process in injection molding, heating, melting, and uniformly mixing raw materials. Under normal circumstances, the plasticizing system should operate smoothly and with low noise levels (typically below 75 decibels). Excessive plasticizing noise (over 85 decibels) not only impacts the production environment but may also signal equipment failure. Long-term neglectMore

Injection Molding Water Ripples and Solutions Injection molding water ripples are a common surface defect in products. They appear as wavy stripes distributed along the direction of melt flow, resembling ripples on the water surface. They seriously affect the visual effect and surface finish of the product, and are especially noticeable in light-colored or transparent products. The generation of waterMore

Injection mold test matters needing attention Injection molding trials are a critical verification step before a mold is officially put into production. This process requires rigorous control of every detail to accurately assess mold performance and determine optimal process parameters. Improper operation during the trial process can not only distort trial data but also damage the mold or equipment, impactingMore

Preparation of injection molding test mold Injection mold trials are a critical step in verifying mold design rationality and determining the optimal molding process. Adequate preparatory work directly impacts trial efficiency and the reliability of the results. Thorough preparation reduces unexpected downtime during trial runs, ensures accurate data on mold performance and product quality, and provides a foundation for moldMore

Deep cylinder plastic parts exhaust Deep cylindrical plastic parts are representative complex products in injection molding. Their height is usually greater than 1.5 times their diameter, such as water cups, pen holders, motor housings, etc. During molding, these products are prone to gas accumulation due to the deep cavity and long melt flow path, leading to defects such as materialMore

Injection mold management (mold installation) is a critical step before injection molding production, directly impacting production efficiency, product quality, and equipment safety. Scientific mold management ensures that molds are installed quickly and accurately on the injection molding machine, minimizing downtime and reducing the risk of mold and equipment damage. Mold management encompasses the entire process, including mold acceptance inspection, pre-installationMore

Calculation of Tie Rod Length for Three-Plate Injection Moulds Calculating the tie rod length for a three-plate injection mold is a critical step in its design, directly impacting the coordination and safety of the mold’s opening and closing movements. Because a three-plate mold has two parting surfaces (the sprue parting surface and the cavity parting surface), tie rods are requiredMore

How to achieve feed balance Feed balance is key to ensuring consistent quality across multiple-cavity injection molds. It ensures that the melt fills all cavities simultaneously and evenly, keeping deviations in weight, dimensions, and mechanical properties within acceptable limits. Unbalanced feed can lead to underfilling (flash) in some cavities, overfilling (flash) in others, or significant differences in shrinkage between products,More

Molding properties of thermoplastics The molding properties of thermoplastics refer to their physical characteristics, such as flow, cooling, and shrinkage, exhibited during processes like injection molding and extrusion. These properties directly determine the choice of molding process and the stability of product quality. Unlike thermosets, thermoplastics are reversible, softening upon heating and hardening upon cooling. Their molding properties are primarilyMore

Selection of hot injection nozzles The selection of injection molding hot nozzles is a key step in the design of hot runner systems, directly affecting the surface quality of the product, molding efficiency, and material adaptability. As the final channel for the melt to enter the mold cavity, the hot nozzle must be accurately selected based on factors such asMore

Sprue bushing for hot runner injection mold The sprue bushing of a hot runner injection mold is a key component connecting the injection molding machine nozzle to the hot runner system. Its function is to smoothly guide the melt ejected from the injection molding machine into the hot runner plate while isolating heat transfer between the nozzle and the moldMore

Injection hot runner plate design The design of the injection molding hot runner plate is the core guarantee of the hot runner system’s performance, directly determining the uniformity of melt distribution, temperature stability, and overall mold efficiency. As a key component connecting the main channel to each hot nozzle, the hot runner plate must simultaneously meet the multiple requirements ofMore

Common shapes of injection molding hot runner plates The injection molding hot runner plate is the core component of the hot runner system. Its function is to evenly distribute the melt from the main channel to each gate and maintain a stable melt temperature through built-in heating elements. The shape of the hot runner plate directly affects melt flow uniformity,More

Material shortage (under-injection) and solutions Short shots are a common defect in injection molding. They occur when the melt fails to completely fill the mold cavity, resulting in partially underfilled parts. These defects can include missing corners, missing ribs, or unclosed holes. These defects not only affect the product’s appearance but can also weaken its structural strength and lead toMore

Preheating of injection molded inserts is a key process step to improve the bonding strength between the insert and the plastic and reduce the internal stress of the product. It is especially suitable for scenarios where metal inserts and plastics are composite molded. The thermal expansion coefficients of metal inserts and plastics are quite different. If a cold insert isMore

Air marks (shadows) and their solutions Air marks (or shadows) are common cosmetic defects in injection molding. They appear as cloud-like streaks or dark shadows on the surface of the product, aligned with the direction of melt flow. These streaks severely degrade the product’s visual quality, and are particularly noticeable in light-colored or transparent products. Air marks are closely relatedMore

Three methods of gas-assisted injection molding Gas-assisted injection molding is an advanced molding technology developed on the basis of traditional injection molding. By injecting high-pressure gas into the melt, the gas pressure is used to push the melt to fill the cavity, maintain pressure and compensate for shrinkage, effectively solving defects such as shrinkage marks and warping of thick-walled products,More

Cooling circuit for common cores The cooling circuit of an ordinary core is a core component of the injection mold cooling system, directly affecting the cooling rate, molding cycle, and dimensional stability of plastic products. As a key component on the inner surface of the molded product, the core continuously absorbs heat from the melt during the injection molding process.More

Injection nozzle casting and solution Injection nozzle flow refers to the phenomenon of continued plastic melt flowing out of the nozzle of an injection molding machine after injection has stopped, commonly known as “drooling.” This phenomenon not only wastes raw material but also contaminates the mold parting surface and nozzle. It can even cause cold material to enter the moldMore

Effect of color matching pigments on the strength of injection molded parts Color pigments are key materials used to adjust the exterior color of injection molding products. However, they not only affect the product’s visual appearance but can also significantly impact its mechanical strength. The strength of injection-molded parts primarily depends on the molecular structure and crystallinity of the plasticMore

Exhaust system design principles The exhaust system is an essential component of injection molds, and the rationality of its design directly affects the molding quality and production efficiency of plastic products. During the injection molding process, if the air in the mold cavity and the volatiles generated by the heated plastic melt are not discharged in a timely manner, defectsMore

Inner mold insert tapered surface positioning Conical surface positioning of inner mold inserts is an important structural form in injection molds to ensure the precise fit between inserts and templates. The self-centering effect of the conical surface enables precise positioning of inserts in the mold, effectively improving the mold closing accuracy and the dimensional stability of the molded product. InMore

Design of injection-molded wear-resistant blocks Injection wear blocks are key components used to reduce wear on moving parts in molds. They are mainly installed in frequently moving areas such as guide pins, guide sleeves, and ejectors. Their wear resistance protects the main structure of the mold and extends the service life of the mold. During the injection molding process, moldMore

Injection mold production follow-up is a critical step in ensuring timely and quality mold delivery, and it runs through the entire process from mold design, manufacturing, mold trialing, to final acceptance. This work requires coordination among multiple departments, including design, processing, assembly, and quality inspection, to promptly identify and resolve problems in the production process to avoid delays or qualityMore

The role and function of injection mold parts An injection mold is a complex system composed of numerous parts, each with a specific role and function. They work together to complete the plastic molding process. From the cavity and core that form the product shape, to the guide components that ensure mold precision, to the ejector components that enable productMore

Use and maintenance of injection molds The use and maintenance of injection molds are critical to ensuring smooth injection molding production, extending mold life, and ensuring stable product quality. In actual production, many mold failures and product defects are related to improper use and inadequate maintenance. Therefore, establishing a scientific and reasonable mold use and maintenance system is crucial forMore

Structure of injection mold frame The injection mold frame is the basic framework of the injection mold, acting as the mold’s “skeleton,” supporting the mold’s various functional components and ensuring their precise fit and stable operation during the injection molding process. The mold frame’s structural design directly affects the mold’s assembly accuracy, service life, and molding efficiency, and therefore playsMore

Injection molded seal Injection-molded seals are widely used components in the sealing field. Manufactured through the injection molding process, they exhibit excellent elasticity, wear resistance, and corrosion resistance, effectively preventing the leakage of liquids, gases, or dust. They play a vital role in the automotive, machinery, chemical, and electronics industries. Injection-molded seals come in a variety of shapes, with O-rings,More

Calculation of thread core size Thread cores are critical components used in injection molds to form the threaded structure of plastic products. Their dimensional accuracy directly impacts the thread quality and assembly performance of plastic products. Calculating thread core dimensions requires comprehensive consideration of factors such as the plastic material’s shrinkage, the thread’s precision level, and molding process parameters toMore

Diameter of tapping bottom hole of screw hole The bottom hole diameter for tapping a screw is a crucial parameter in machining, directly impacting thread quality, connection strength, and assembly precision. The bottom hole refers to the hole drilled before tapping. Its diameter must be precisely calculated and selected based on factors such as the thread specifications, thread profile, andMore

Injection Molding Screw Slippage and Solutions Injection screw slippage is a common malfunction during the injection molding process. This occurs when the molten plastic is not effectively conveyed forward as the screw rotates and propels it forward. Instead, it slips relative to the barrel, leading to unstable melt flow and, in turn, impacting product quality and production efficiency. This phenomenonMore

Injection Cracks (Cracks) and Solutions Injection cracks, also known as crazing, are common defects in the injection molding process. These microscopic cracks appear on or within the product, severely impacting its appearance and mechanical properties. The occurrence of these defects is often closely related to multiple factors, including raw material properties, molding process parameters, and mold design. Cracks can appearMore

The connecting rod pre-reset mechanism is a crucial auxiliary device in injection molds. Its primary function is to ensure that the ejector mechanism resets before the side core pulling mechanism during mold opening and closing, thereby preventing interference between the two and ensuring proper mold operation. This mechanism consists of key components, including a connecting rod, rocker arm, slider, andMore

Injection molding cooling system example The design of an injection molding cooling system must be customized based on the specific characteristics of the plastic part and production requirements. Different types of plastic parts (such as thin-walled parts, thick-walled parts, and parts with complex structures) place significantly different demands on the cooling system. Proper cooling system examples can provide a referenceMore

Connection and sealing of injection molding cooling water channels The connection and sealing of injection molding cooling channels are critical to ensuring the proper functioning of the cooling system, directly impacting the flow and pressure of the cooling medium and the lifespan of the mold. Improper connections or seal failures can lead to cooling medium leakage, reducing cooling efficiency andMore

Calculation of the total length of the injection molding cooling circuit Calculating the total length of the injection molding cooling circuit is a critical step in mold cooling system design, directly impacting the cooling efficiency and molding cycle of the molded part. A reasonable cooling circuit length ensures rapid and even cooling of the melt within the mold, reducing defectsMore

Strain (strain) and its solution Scratches (or “drag marks”) are common surface defects in injection molding. They occur when the mold cavity or core surface scrapes the surface of the part during the demolding process, resulting in scratches, burrs, or partial material loss. These defects not only affect the product’s appearance but, in severe cases, can damage the part’s structuralMore

Open hot injection nozzle An open hot-runner nozzle is a crucial gating system component in injection molding, primarily used in hot-runner molds. Its function is to transport molten plastic from the injection molding machine nozzle to the mold cavity while maintaining a stable melt temperature within the runner to prevent blockage caused by melt cooling and solidification. Compared to closedMore

Precision injection molding process Precision injection molding is an advanced manufacturing technology capable of producing plastic parts with high dimensional accuracy, excellent surface quality, and stable mechanical properties. It is widely used in high-end industries such as automotive, electronics, medical, and aerospace. Compared to conventional injection molding, precision injection molding has more stringent requirements for mold accuracy, process parameter control,More

Metal insert defects and solutions In injection molding, combining metal inserts with plastic is a common process, improving properties such as strength, wear resistance, and conductivity. However, metal inserts often exhibit defects during use, such as loose inserts, cracking at the plastic-insert junction, and insert corrosion. These issues not only affect product performance but can also pose safety risks. AddressingMore

Effective measures to solve the problem of oil loss after oil spraying on low-hardness soft plastic parts Low-hardness soft plastic parts (such as those made from TPU, EVA, and PVC) often experience oil shedding after spray coating. This occurs when the coating is not firmly bonded to the surface and easily falls off, affecting not only the product’s appearance butMore

During the injection molding process, the venting performance of the gating system directly impacts product quality. As one of the most important venting areas within the mold, the rationality of its venting design is crucial. The parting surface is the interface between the movable and fixed molds. When the melt fills the cavity, if the existing air, gases generated byMore

Flow balance in injection molding gating systems Flow balance in the injection molding gating system is a key factor in ensuring consistent quality across multiple cavities in a multi-cavity mold. It requires the melt to fill each cavity in the same state and at the same time, avoiding dimensional deviations and uneven mechanical properties in the product due to fillingMore

The reasons why gas marks or spray marks are easily generated at the gate During the plastic injection molding process, air marks or jet marks at the gate are common defects that not only affect the product’s appearance but can also reduce its mechanical properties. These defects are often closely related to a variety of factors, including injection molding processMore

Selection of screws for several commonly used plastic injection molding In plastic injection molding, the screw, as the core component of the injection molding machine, directly impacts the plasticizing quality, molding efficiency, and final product performance. Different types of plastics have varying physical and chemical properties, such as melting temperature, melt viscosity, fluidity, and thermal stability. Therefore, the right screwMore

Injection molding color mixing and solutions Color mixing during injection molding refers to defects such as uneven color, streaks, and spots on the surface or interior of a molded part, resulting in a product appearance that does not meet design requirements. This defect is common during the production of colored or multi-color composite parts. This defect can occur in plasticsMore

Injection molded slider type distance mechanism The injection molding slider-type spacing mechanism is a key device for controlling the sequential opening of the mold’s parting surfaces. This mechanism achieves fixed-distance parting through the sliding of the slider, ensuring that the different parting surfaces open in a preset sequence during the mold opening process. This facilitates core pulling, part removal, orMore

The injection molding slider locating clamp is a key component used to secure the slider in the side core-pulling mechanism. Its function is to lock the slider in the working position when the mold is closed, preventing injection pressure from causing the slider to move. When the mold is opened, it releases with the slider’s movement, ensuring smooth core-pulling. ThisMore

Injection molding tiger stripes and solutions Injection molded tiger stripes are alternating light and dark stripes resembling tiger fur that appear on the surface of a plastic part. They often appear on large surfaces or thick-walled areas of plastics such as ABS, PC/ABS, and HIPS, severely impacting the product’s appearance quality. This defect typically occurs along the direction of meltMore

Injection molded black stripes (black lines) Injection molding black streaks (black lines) are dark streaks or linear defects that appear on the surface of plastic parts. They are usually distributed along the direction of melt flow, seriously affecting the appearance of the product and are particularly noticeable in light-colored or transparent plastic parts. This defect is common in the moldingMore

Composition and properties of domestic plastic mold steel Domestic plastic mold steel is a key material supporting the development of my country’s injection mold industry. Its composition and performance optimization must meet the specific mold requirements of plastic molding, such as wear resistance, polishability, corrosion resistance, and processability. In recent years, with advances in domestic steelmaking technology, the quality ofMore

Several Problems on Air Traps and Their Improvement Measures Air entrapment is a common defect in injection molding caused by the inability to expel gas from the mold cavity in a timely manner. It manifests as scorching on the surface of the plastic part, bubbles, missing material, and noticeable weld marks. This not only affects the product’s appearance but canMore

The applicability of various plastics to hot injection nozzles As a core component of a hot runner system, the hot nozzle’s material, structure, and heating method must match the plastic’s characteristics. The differences in melt temperature, fluidity, corrosiveness, and viscosity between different plastics directly determine the applicable hot nozzle type. For example, high-temperature plastics (such as PEEK) require a hotMore

Shape of the water-passing end of the spacer The water-passing end of the spacer is a key component for controlling the flow state of the coolant in the mold cooling system. Its shape directly affects the cooling efficiency, water flow resistance and mold temperature uniformity. In the cooling water channel of the injection mold, spacers are usually used to separateMore

Orientation during polymer molding Orientation during polymer molding refers to the phenomenon in which polymer chains or segments align in a specific direction under the influence of external forces (such as shear and tension). This structural change can significantly affect the mechanical, optical, and dimensional stability of the resulting molded part. Orientation is a common phenomenon in molding processes suchMore

Injection reset and pre-reset mechanism The injection molding reset and pre-reset mechanisms are key devices that ensure that the mold ejection system and core pulling mechanism can accurately return to their initial positions after mold opening. Their performance directly affects mold closing accuracy and production safety. The reset mechanism is responsible for returning the ejection components (such as the ejectorMore

The design of the parting surface position is a key step in injection mold design that determines the quality of plastic parts and production efficiency. Its position selection must follow a series of general principles to balance the appearance of the plastic part, dimensional accuracy, demolding difficulty, and mold manufacturing costs. A reasonable parting surface position can simplify the moldMore

Shape design of injection molding parting surface The shape design of the injection molding parting surface is a core part of mold structure design, which directly affects the demolding effect, appearance quality and mold processing difficulty of the plastic part. The parting surface is the contact surface between the movable mold and the fixed mold. Its shape must match theMore

Injection molding unbalanced arrangement An unbalanced arrangement for injection molding refers to a layout in which the distances between each cavity and the main runner in a multi-cavity mold are inconsistent. The melt enters the cavity through branch runners of varying lengths, resulting in differences in filling time and pressure. Compared to a balanced arrangement, an unbalanced arrangement is moreMore

Injection Molding Brittleness and Solutions Injection molding brittleness refers to the phenomenon that plastic parts show decreased mechanical properties, insufficient toughness, and are prone to cracks or fractures after molding, which not only affects the service life of the product, but may also cause safety hazards. This defect is particularly obvious in low temperature environments or under stress. For example,More

Installation of the second-plate sliding foot (pad iron) support mechanism The second-plate slide (shim) support mechanism is a critical connection between the movable mold and the injection molding machine worktable. Its primary function is to support the mold’s weight, adjust the mold’s levelness, and guide the movable mold’s smooth movement during mold opening and closing. This ensures precise alignment betweenMore

Multi-point hot runner injection mold A multi-point hot runner injection mold is a highly efficient molding device that simultaneously injects molten plastic into multiple cavities via multiple hot runner nozzles. Its core principle is to utilize a manifold to evenly distribute the melt to each gate, enabling simultaneous filling and curing of multi-cavity plastic parts, significantly improving production efficiency andMore

Injection mold slider T-block The T-block on the movable mold slider is the core, load-bearing component of the lateral core-pulling mechanism. It primarily connects the slider to the movable mold plate. The T-slot ensures smooth sliding of the slider and withstands the lateral forces generated during core pulling, ensuring precise and reliable core pulling. In the molding of parts withMore

Design of injection molding positioning system The injection molding positioning system is a core structure that ensures mold closing accuracy and part dimensional stability. Through the coordination of guide pins, guide bushings, and locating pins, it ensures precise alignment between the movable and fixed molds during mold closing, preventing flash, dimensional deviations, and mold damage caused by misalignment. The accuracyMore

Fixed mold push rod and movable mold push rod composite demoulding Combined demolding using both fixed and movable mold ejectors is a highly efficient demolding method for complex-shaped plastic parts. By employing ejector mechanisms on both the fixed and movable molds, this method solves the demolding challenges of parts with deep cavities, undercuts, or large surfaces, which are difficult toMore

Injection molding whitening (top pop) is a common defect during the demolding process of plastic parts. It manifests as white marks or localized cracks at the ejection site, which not only affects the product’s appearance but can, in severe cases, lead to the scrapping of the plastic part. Whitening typically occurs at the contact points between the ejector pin, ejectorMore

Injection molded thermal water channel Injection molding thermal conductive water channels are a core component of the mold cooling system. By opening channels inside the mold cavity and core to allow the introduction of media such as cooling water or hot oil, precise temperature control of the mold is achieved, thereby affecting the molding quality and production efficiency of theMore

Single-point hot runner injection mold A single-point hot runner injection mold is a mold structure that injects molten plastic directly into the mold cavity through a single hot runner system. Its core feature is the elimination of the traditional cold runner, allowing the melt to remain molten throughout the entire process from the nozzle to the cavity, reducing material wasteMore

Technologies and techniques for solving deformation problems of large flat plastic parts Large flat plastic parts are prone to deformation after injection molding, manifesting as warping, bending, denting, or undulations. This not only affects product assembly precision but can also lead to functional failure. These parts typically have a surface area exceeding 500 cm² and a relatively thin thickness (1-3More

DAMIC process for handling product defects The DAMIC process for addressing product defects is a systematic approach based on Six Sigma management. Through a closed-loop management process consisting of five stages: Define, Measure, Analyze, Improve, and Control, it accurately identifies and resolves quality defects in injection molded products, reducing defect rates and improving production stability. Compared to traditional empirical approaches,More

Injection liquid filling and pressurized mold clamping device The injection molding liquid-filled pressurized mold clamping device is a high-efficiency mold clamping mechanism that is widely used in large injection molding machines or molding scenarios that require high clamping force. It takes into account both the clamping speed and the clamping force through the combined action of liquid-filled rapid mold shiftingMore

Gear rack dethreading mechanism The rack-and-pinion thread stripping mechanism is a key device in injection molds for processing products with internal or external threads. Through the meshing transmission of the gear and rack, it converts the mold opening and closing motion into the rotational motion of the threaded core or ring, enabling automatic demolding of threaded products and significantly improvingMore

Solution to long injection molding cycle The injection molding cycle refers to the time required to complete the entire injection molding process, including mold closing, injection, pressure holding, cooling, mold opening, and ejection. Excessively long cycles directly reduce production efficiency and increase production costs. In large-scale production, every 1-second reduction in the molding cycle can increase the output of dozensMore

Polishing of injection molded surfaces The quality of the injection molded surface finish directly impacts the product’s appearance and performance. This is especially true for high-precision products like transparent and decorative parts, where the polishing process is a crucial step in determining product quality. By gradually refining the abrasive grit, the polishing process removes machining marks from the mold cavityMore

The thermal processing and heat treatment of plastic mold steel are key factors in determining mold performance, directly impacting its hardness, wear resistance, toughness, and service life. Commonly used plastic mold steels include pre-hardened mold steels (such as 718H and NAK80), age-hardened mold steels (such as P20 and 45# steel), and cold-work mold steels (such as Cr12MoV). Different types ofMore

Simple identification method of common plastics Quickly and accurately identifying plastic types is crucial in applications such as plastic recycling, product repair, and material selection. Common plastics include polyethylene (PE), polypropylene (PP), polyvinyl chloride (PVC), polystyrene (PS), polyethylene terephthalate (PET), and acrylonitrile-butadiene-styrene (ABS). Each plastic has unique physical and chemical properties, allowing for easy differentiation through simple methods such asMore

Analysis and treatment of injection molding product defects Injection molded products inevitably develop various defects during the production process. These defects not only affect the product’s appearance quality but may also reduce its mechanical properties and safety. Common injection molding defects include flash, sink marks, bubbles, weld marks, and warpage. The occurrence of each defect is closely related to factorsMore

Interference phenomenon and countermeasures in the process of lateral core pulling Interference is a common problem in the operation of the lateral core-pulling mechanism of injection molds, impacting production efficiency and product quality. This phenomenon typically manifests as unexpected collisions or jamming between the core-pulling component and other mold components during movement. This can lead to mold wear at best,More

The injection molded surface is dull or has uneven gloss. Dull or uneven gloss on injection molded parts is a common appearance defect that directly impacts the product’s visual quality and market competitiveness. This is particularly true in applications requiring high appearance standards, such as automotive interiors, appliance housings, and medical devices, where such defects can lead to product rejection.More

Categories of standard injection mold bases A standard mold frame for injection molding is the basic framework of the injection mold. It is assembled from standardized parts such as the fixed mold base, movable mold base, mold plate, guide pins, and guide sleeves. Its function is to support the mold cavity, ensure mold opening and closing accuracy, and transmit clampingMore

Injection molding flap demoulding Injection molding flap-type demoulding is a special demoulding method for complex-shaped plastic parts (such as those with inner grooves, threads, or irregular protrusions). Its core principle is to achieve the smooth release of plastic parts from the mold through the coordinated movement of multiple detachable flap modules (also known as half blocks). Compared with traditional ejectorMore

Improvement measures for weld marks and water ripples in PVC injection molded parts PVC (polyvinyl chloride), a low-cost plastic material with diverse properties, is widely used in injection molding. However, during the production process, PVC injection molded parts are prone to cosmetic defects such as weld marks and water ripples. These defects not only affect the product’s aesthetics but canMore

The reasons why shrinkage holes in PC plastic parts are difficult to solve and their solutions As a high-performance engineering plastic, PC (polycarbonate) is widely used in electronics, automotive, and medical devices due to its excellent mechanical properties, heat resistance, and transparency. However, shrinkage holes often present a production challenge during PC injection molding. These holes not only affect theMore

During the K-material injection molding process, ejector pin breakage is a common problem that impacts production efficiency and product quality. This problem is often linked to multiple factors, including mold design, process parameter settings, and material properties. Frequent ejector pin breakage, a critical component for demolding plastic parts, can not only lead to downtime and repairs, increasing production costs, butMore