Gas mark is a quality defect that is easy to produce and difficult to eliminate. Gas mark not only affects appearance of product, but also affects strength of product. Relevant domestic technical data does not involve much of mechanism of generating gas mark. When operator encounters specific problems, he cannot quickly find cause of problem. He do not know what process measures to take, problem cannot be solved in time, resulting in a large amount of waste of resources which will cause huge losses to enterprise.
Plastic Automotive Fasteners, and plastic fastening components are produced at National Molding's US and China facilities. Our rapid response engineers partner with auto parts manufacturers to ensure that our standard plastic automotive parts and plastic automotive fasteners are the highest quality and the best fit for their spec and production needs. National molding will quickly and cost-effectively produce the right plastic automotive fastener and plastic fastening component for any auto manufacturer.
Solutions to silver defects in injection molded parts -dgmf mold clamps co., ltdJasmineHL
Silver pattern: The needle-like silvery-white frost-like fine lines on the surface of the injection molded part. The direction of the opening is along the direction of the flow. Where the plastic part is not completely filled, the front end of the fluid is rough Silk pattern).
How to set the injection molding material temperature -dgmf mold clamps co., ltdJasmineHL
In injection molding, temperature is one of the five major factors in injection molding, which affects the plasticizing effect of the material, the flow rate of the solution, the crystallization rate, and the cooling rate of the mold. Reasonable use of temperature control can reduce a lot of detours when debugging process parameters. Let's explore the influence of temperature in the forming process together.
Influence of injection molding process on product quality -dgmf mold clamps c...JasmineHL
During the molding process of converting plastic particles into plastic products, plastics are often subjected to high temperature and high pressure and flow molding at high shear rates. Different molding conditions and processes will have different effects on product quality. Plastic injection molding has plastics. Raw materials, injection molding machines, molds and injection molding processes are composed of four aspects.
Gas mark is a quality defect that is easy to produce and difficult to eliminate. Gas mark not only affects appearance of product, but also affects strength of product. Relevant domestic technical data does not involve much of mechanism of generating gas mark. When operator encounters specific problems, he cannot quickly find cause of problem. He do not know what process measures to take, problem cannot be solved in time, resulting in a large amount of waste of resources which will cause huge losses to enterprise.
Plastic Automotive Fasteners, and plastic fastening components are produced at National Molding's US and China facilities. Our rapid response engineers partner with auto parts manufacturers to ensure that our standard plastic automotive parts and plastic automotive fasteners are the highest quality and the best fit for their spec and production needs. National molding will quickly and cost-effectively produce the right plastic automotive fastener and plastic fastening component for any auto manufacturer.
Solutions to silver defects in injection molded parts -dgmf mold clamps co., ltdJasmineHL
Silver pattern: The needle-like silvery-white frost-like fine lines on the surface of the injection molded part. The direction of the opening is along the direction of the flow. Where the plastic part is not completely filled, the front end of the fluid is rough Silk pattern).
How to set the injection molding material temperature -dgmf mold clamps co., ltdJasmineHL
In injection molding, temperature is one of the five major factors in injection molding, which affects the plasticizing effect of the material, the flow rate of the solution, the crystallization rate, and the cooling rate of the mold. Reasonable use of temperature control can reduce a lot of detours when debugging process parameters. Let's explore the influence of temperature in the forming process together.
Influence of injection molding process on product quality -dgmf mold clamps c...JasmineHL
During the molding process of converting plastic particles into plastic products, plastics are often subjected to high temperature and high pressure and flow molding at high shear rates. Different molding conditions and processes will have different effects on product quality. Plastic injection molding has plastics. Raw materials, injection molding machines, molds and injection molding processes are composed of four aspects.
What is mold temperature in injection molding?JasmineHL
The mold temperature in injection molding is probably the most important temperature in terms of quality and this affects quality in many ways. The mold temperature is not the same thing as the cooling water temperature, it is the temperature of the actual mold cavity after it has stabilized.
R.D. Mould & Industry™ provides wide range of plastic spoon mould for production of plastic spoons for various purposes like: Plastic spoon for Ice-cream, Plastic Forks, Plastic Stirrer, Plastic Birthday Knife, Silver Plated Spoons & much more
Five elements of injection molding process parametersJasmineHL
The injection molding process is one of the four major plastic molding processes. The barrels, basins, toys, and other daily products we use in our lives are all formed by the injection molding process. So what are the important factors to pay attention to in the plastic injection molding process?
The completion of the injection molding process generally requires six processes of clamping, filling, holding pressure, cooling, demolding, and opening the mold. In these six processes, we must remember these five elements, namely pressure, speed, position, temperature, and time.
1. Causes of dents
1.1 The thickness of each part of the product is different
1.2 Insufficient pressure inside the mold
1.3 Insufficient mold cooling
1.4 Deformation due to the insufficient cooling time
What is the 4 process of plastic injection molding?JasmineHL
The plastic injection molding process mainly includes four stages: filling, holding pressure, cooling, and demolding. These four stages directly determine the molding quality of the product, and these four stages are a complete continuous process.
Introduction,Purpose,Injection Molding,Process Cycle,Injection Machine,Products of Injection Molding,Identification and chemical properties. The purpose of the industrial training is to provide exposure for the students on practical fields. Through this exposure, students will have better understanding of practice in general and sense of frequent and possible problems. This training is part of the learning process which exposes to uplifts the knowledge and experience of a student needs to be properly documented in the form of a report.
Mold clamp tools definition
What is mold clamp? The mold clamp (also called mould clamp) is a kind of auxiliary clamping unit often used in injection mold processing, its main function is to keep the machined parts not shaking not moving in the processing.
What determines high performance plasticsJasmineHL
The following six factors determine the high-performance plastics.
(1) The type of polymer determines high-performance plastics
The performance is also different because of the different polymer links, such as acetal resin (POM) impact strength, then the unsaturated polyester resin (UP) is more excellent. Even if the same material, structure, and polymerization degree are different, the performance varies significantly.
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Similar to 13 common bad defects of injection molded products
What is mold temperature in injection molding?JasmineHL
The mold temperature in injection molding is probably the most important temperature in terms of quality and this affects quality in many ways. The mold temperature is not the same thing as the cooling water temperature, it is the temperature of the actual mold cavity after it has stabilized.
R.D. Mould & Industry™ provides wide range of plastic spoon mould for production of plastic spoons for various purposes like: Plastic spoon for Ice-cream, Plastic Forks, Plastic Stirrer, Plastic Birthday Knife, Silver Plated Spoons & much more
Five elements of injection molding process parametersJasmineHL
The injection molding process is one of the four major plastic molding processes. The barrels, basins, toys, and other daily products we use in our lives are all formed by the injection molding process. So what are the important factors to pay attention to in the plastic injection molding process?
The completion of the injection molding process generally requires six processes of clamping, filling, holding pressure, cooling, demolding, and opening the mold. In these six processes, we must remember these five elements, namely pressure, speed, position, temperature, and time.
1. Causes of dents
1.1 The thickness of each part of the product is different
1.2 Insufficient pressure inside the mold
1.3 Insufficient mold cooling
1.4 Deformation due to the insufficient cooling time
What is the 4 process of plastic injection molding?JasmineHL
The plastic injection molding process mainly includes four stages: filling, holding pressure, cooling, and demolding. These four stages directly determine the molding quality of the product, and these four stages are a complete continuous process.
Introduction,Purpose,Injection Molding,Process Cycle,Injection Machine,Products of Injection Molding,Identification and chemical properties. The purpose of the industrial training is to provide exposure for the students on practical fields. Through this exposure, students will have better understanding of practice in general and sense of frequent and possible problems. This training is part of the learning process which exposes to uplifts the knowledge and experience of a student needs to be properly documented in the form of a report.
Mold clamp tools definition
What is mold clamp? The mold clamp (also called mould clamp) is a kind of auxiliary clamping unit often used in injection mold processing, its main function is to keep the machined parts not shaking not moving in the processing.
What determines high performance plasticsJasmineHL
The following six factors determine the high-performance plastics.
(1) The type of polymer determines high-performance plastics
The performance is also different because of the different polymer links, such as acetal resin (POM) impact strength, then the unsaturated polyester resin (UP) is more excellent. Even if the same material, structure, and polymerization degree are different, the performance varies significantly.
18 Basic Injection Molding Technologies
Below are the 18 basic injection molding technologies that injection molding technicians must know.
01. Nozzle in the injection molding technologies
The melt usually flows from the nozzle into the nozzle, but in some injection molds, the nozzle is part of the mold because it extends to the bottom of the mold. There are also two main types of nozzles: open nozzles and closed nozzles. In injection molding, open nozzles should be used more because they are cheaper and less likely to stay.
If the injection molding machine is equipped with a pressure-removing device, this nozzle can be used even for low-viscosity melts. Sometimes a closed nozzle must be used. This nozzle acts as a stop valve to block the plastic in the injection cylinder.
Make sure that the nozzle is correctly connected to the nozzle bushing, and the top hole is slightly smaller than the nozzle sprue bushing, which makes the nozzle easier to withdraw from the injection mold. The hole of the nozzle sleeve is 1mm larger than the nozzle, that is, the radius of the nozzle is 0.5mm smaller than the radius of the nozzle sleeve.
What is progressive stamping die?
Progressive stamping is a metalworking method that can encompass punching, coining, bending, and several other ways of modifying metal raw material, combined with an automatic feeding system. The feeding system pushes a strip of metal through all of the stations of a progressive stamping die.
The progressive stamping die refers to a cold stamping die that uses a strip of stamping raw material to complete multiple stamping processes simultaneously with several different stations on one die in one stamping stroke, and the material strip moves at a fixed distance once for each stamping stroke until the product is finished.
Reasonable product design and mold design are key technologies that affect the success of injection molding. This article introduces some basic principles of injection molded product design and mold design.
1. The basic conditions of plastic product design
1.1. Record the product usage conditions as detailed as possible.
These conditions are:
A. Use environment
Outdoor conditions (sunlight, rain, ice, snow, dust), sunlight (ultraviolet rays, radiation, etc.), contact with gas (corrosive gas, water vapor), contact with liquid (water, detergent, oil, medicine, etc.), other (plasticizers), copper);
B. Use intensity
Common temperature, maximum temperature, minimum temperature (usually, special circumstances, outdoor, warehouse, window, car, etc.), repeated cold and hot
C. Use load
Common load, maximum load (normal, special circumstances. Static, dynamic, repeated, continuous, impact, drop, etc.).
Mold components refer to the general name of metal accessories used in stamping dies, plastic molds, or FA automation equipment exclusively in the mold industry.
Here we are going to introduce 60 kinds of the mold components.
Precautions for injection mold maintenanceJasmineHL
Injection mold, as the most important production tool of injection molding factory, determines the shape, specification, size and appearance finish of the product. The material of the mold is steel, which is generally composed of a front mold and a back mold.
Injection mold is a tool for producing plastic products; it is also a tool for giving plastic products a complete structure and precise dimensions. The structure of the injection mold and the quality of mold processing directly affects the quality and production efficiency of plastic parts. The most common and most common causes of injection mold failures and troubleshooting methods in the production of injection molds and plastic products are described in detail as follows:
What are the key points of precision injection moldingJasmineHL
Precision injection molding is affected by many related factors and environmental conditions, and the most basic are the four basic factors of plastic materials, injection molds, injection molding processes, and injection molding equipment.
In the early stage of designing plastic products, engineering plastics with corresponding performance requirements should be selected according to the application environment.
Secondly, the appropriate injection molding machine should be selected according to the selected plastic material, finished product dimensional accuracy, part weight, quality requirements, and expected mold structure.
Plastic products are made of a mixture of synthetic resin and various additives as raw materials, using injection, extrusion, pressing, pouring, and other methods. While plastic products are being molded, they also obtain the final performance, so plastic molding is a key production process.
The following are 10 common plastic Injection molding methods.
Basic requirements for plastic injection molded part designJasmineHL
Plastic Part Design Basic Requirements
Unreasonable design of plastic injection molded parts often results in some inherent defects in the product. For example, the structure of the parts is unreasonable, the parts use too much material, etc. Here are a series of basic requirements for plastic injection molded parts design for reference.
Secrets of injection molding process adjustmentJasmineHL
The close relationship between injection speed and product quality makes it a key parameter of injection molding. By determining the start, middle, and end of the filling speed segment, And to achieve a smooth transition from one set point to another set point, a stable melt surface speed can be ensured to produce the desired molecule and the smallest internal stress.
The cold forging, cold extrusion, and cold heading are general terms for plastic processing. Cold forging, also called cold volume forming, is a manufacturing process and a processing method. Cold forging is the forming process below the recrystallization temperature of the material, and the forging performed below the recovery temperature.
What is the difference between blow molding and injection moldingJasmineHL
What Is The Difference Between Blow Molding And Injection Molding?
First, the process is different
Blow molding: Blow molding uses gas pressure to inflate the hot parison closed in the mold into a hollow product, or the tube parison is inflated into a tube film without a mold.
Injection molding: injection molding is to melt plastic materials, and then inject them into the film cavity to form.
Blow molding is a manufacturing process for forming and joining together hollow plastic parts. It is also used for forming glass bottles or other hollow shapes. In general, there are three main types of blow molding: extrusion blow molding, injection blow molding, and injection stretch blow molding.
The inclined top mold is also known as the inclined tip. It is the mechanism used to mold the internal barbs of the product in the mold design. It is suitable for relatively simple barbs.
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Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
• Remote control: Parallel or serial interface.
• Compatible with MAFI CCR system.
• Compatible with IDM8000 CCR.
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
• Easy in configuration using DIP switches.
Technical Specifications
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
Key Features
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
• Remote control: Parallel or serial interface
• Compatible with MAFI CCR system
• Copatiable with IDM8000 CCR
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
Application
• Remote control: Parallel or serial interface.
• Compatible with MAFI CCR system.
• Compatible with IDM8000 CCR.
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
• Easy in configuration using DIP switches.
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13 common bad defects of injection molded products
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13 common bad defects of injection molded products
Written By Jasmine HL
1. Dissatisfaction (lack of plastic)
Process issues: the plasticizing temperature is too low, the nozzle temperature is too low, the
injection time is too short, the injection speed is too slow, and the mold temperature is too low;
Mold problems: The runner is too small, the gate is too small, the gate location is not reasonable,
the exhaust is poor, and there is debris in the cavity;
Raw material problems: poor fluidity, mixed with debris.
2. Flash
Process issues: too high plasticizing temperature, too long injection time, too much feed, too high
injection pressure, too high mold temperature, and debris between the templates;
Mold problems: mold deformation, errors in the matching dimensions of the core and cavity,
non-parallel template combinations, and excessive exhaust grooves;
Equipment problems: the template is not parallel and the template is not tightly closed;
Problems with raw materials: Excessive liquidity.
3. Deformation
In terms of process conditions: the material temperature is too high, the mold temperature is too
high, the holding time is too short, and the cooling time is too short to force the demolding;
In terms of mold: improper gate position, insufficient number of gates, improper ejection
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position, uneven force.
4. Flow marks
In terms of process conditions: the material temperature is too low to completely plasticize, the
injection speed is too low, the injection pressure is too small, the holding pressure is not enough,
the mold temperature is too low, and the injection amount is insufficient;
In terms of mold: the gate is too small, the number of gates is too small, the runner gate is rough,
and the surface finish is poor;
In terms of equipment: the system fails after the temperature control and the oil pump pressure
drops;
In terms of raw materials: too many volatiles, poor fluidity, mixed with miscellaneous materials.
5. Bubble
In terms of process conditions: low injection pressure, insufficient holding pressure, insufficient
holding time, and high material temperature;
In terms of mold: poor venting, unreasonable gate location, too small gate size;
In terms of raw materials: the moisture content is not dried or the drying time is not enough, and
the shrinkage is too large.
6. Shrink
In terms of process conditions: insufficient feeding amount, too short injection time, too short
holding time, too high material temperature, too high mold temperature, and too short cooling
time;
In terms of mold: the runner is too small, the gate is too small, and the exhaust is poor;
In terms of equipment: the injection pressure is not enough, and the nozzle is clogged with
foreign objects;
In terms of raw materials: excessive shrinkage.
7. Unstable size
In terms of process conditions: the injection pressure is too low, the barrel temperature is too
high, the holding time varies, and the injection cycle is unstable and the mold temperature is too
high;
In terms of mold: uneven gate size, inaccurate cavity size, loose core, too high mold temperature
or no water channel;
In terms of raw materials: there are changes in grades, uneven particle sizes, and volatile
substances.
8. Difficult demoulding
In terms of process conditions: the injection pressure is too high, the holding time is too long, the
injection volume is too high, and the mold temperature is too high;
Equipment: Insufficient ejection force and insufficient ejection distance;
In terms of mold: no mold release slope, insufficient finish, improper ejection method, improper
cooperation accuracy, poor exhaust, and template deformation.
9. Silver pattern
In terms of process conditions: material temperature is too high, injection speed is too fast, the
injection pressure is too large, uneven plasticization, and too much release agent;
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In terms of mold: the gate is too small, the mold finish is poor, and the exhaust is poor;
In terms of equipment: back pressure is too low, and nozzles have castings;
In terms of raw materials: the moisture content is not dried, and the lubricant is excessive
10. Charred
In terms of process conditions: the material temperature is too high, the injection pressure is too
high, the speed is too fast, the downtime is too long, and the release agent is not clean;
In terms of mold: the gate is too small, the exhaust is poor, the cavity is complicated, and the
cavity finish is poor;
In terms of raw materials: there are impurities in the material, and powder in the granular
material.
11. Discoloration
In terms of process conditions: material temperature is too high, the injection pressure is too
high, the molding cycle is long, mold is not cooled, the nozzle temperature is high;
In terms of mold: the gate is too small;
In terms of equipment: there are obstacles in the barrel or nozzle, and the screw speed is high.
The core is not concentric with the center of the nozzle;
In terms of raw materials: material pollution, colorant decomposition, high volatile content.
12. Weld marks
In terms of process conditions: low injection pressure, short injection time, low material
temperature, too large clamping force, and inappropriate mold release agent;
In terms of mold: the mold temperature is too low, the runner is small, the gate position is
incorrect, and the exhaust is poor;
Equipment: Poor plasticization;
In terms of raw materials: the fluidity is too poor, the lubricant is too much, and the material has
foreign matter.
13. Gloss defect
In terms of process conditions: the material temperature or mold temperature is too low, the
injection pressure is too low, the injection speed is too large or too small, and the cooling time is
too short;
In terms of mold: the mold roughness becomes larger, the gate is too small, the runner is too thin,
and the exhaust is poor;
Equipment: insufficient supply;
In terms of raw materials: the raw materials are not dried or contain volatile substances, the raw
materials are easily degraded, the amount of auxiliary agents or release agents is excessive or the
quality is not good, and foreign matter is contained.