Schlagwortarchiv für: Acryl-Spritzguss

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Acryl-Spritzguss

Acryl-Spritzguss

How Do You Achieve High Quality Acrylic Injection Molding?

It is important to reach a high gloss surface with minimum shrinkage defects when using Acryl-Spritzguss for your injection-molded products. When you make acrylic injection molding parts, some simple points to define the quality of acrylic molding will be: a completely clear high gloss surface, minimum shinkage defects, high precision dimensions (if needed), no break marks, etc.

This blog aims to discuss ways to improve acrylic molding accuracy. Learn strategies, recommendations, and recommendations for success. We pinpoint temperature regulation, pressure levels, and other features. Welcome to the path of precision in acylic molding.

What is Acrylic Injection Molding?

Acrylic injection molding, or PMMA injection molding, is the manufacturing process of melting acrylic resin to be injected into the mold cavity using a high pressure of about 150 MPa (normally between 100 and 170 MPa). The process involves barrel temperatures of between 220 and 260 degrees. Melt flow index (MFI) is essential for controlling viscosity.

To make high-clear acrylic molding parts, the screw, nozzle, and clamping unit can be referred to as critical parts of the molding machine. Cycle times may vary from 30 seconds to 300 seconds, depending on the PMMA Spritzguss-Wandstärke.

Dimensional stability is achieved by stringent regulation of the rate at which the parts are cooled. Mold temperature-control devices control the cooling process. The injection speed also affects the surface finish of the final product.

Acryl-Spritzguss

How to Prepare Acrylic Material for Injection Molding?

Acrylic molding is not an easy process because, typically, when you need acrylic mold parts, you need high-transparent or semi-transparent parts. In that case, it is not allowed to have any issues with the acrylic-molded part from inside to outside. Below are the basic steps to make acrylic-molded parts:

Materialauswahl

Therefore, it is important to select the right acrylic grade of Spritzgussmaterialien. Transparency, strength, and heat resistance are important. Consequently, the melt flow index (MFI) must correspond to the molding process. Employ PMMA that has good optical properties.

Discuss the role of impact modifiers for toughness. It is also important to note that colorants can be incorporated during the mixing phase. It is also important to meet the application requirements of the acrylic resin.

Drying Techniques

During the PAAM molding process, correct drying of acrylic resin reduces imperfections. Desiccant dryers should be used because of their effectiveness in moisture removal.

Drying temperatures vary between 60 and 90 degrees, with a minimum of 3 hours of drying time. Ensure that there is steady air circulation throughout the drying hopper. Measure the moisture level with a hygrometer.

One should make sure to dry all surfaces uniformly to prevent hydrolysis. The drying process normally takes between two and four hours, and make sure to clean the drying hopper and not mix any other type of material with acrylic materials.

Consistency

It is important to be consistent with acrylic injection molding. Total melt viscosity is critical for quality acrylic molding parts. Ensure that the injection unit is calibrated often. Control the temperatures within the barrels and make the necessary adjustments. It has been found that screw speed influences material flow.

Maintain consistent cooling times to minimize warping. Ensure molds are checked frequently for signs of wear and tear.

If you are molding clear acrylic injection molding parts, cleaning the injection unit and barrel will be very important. Make sure there is no other type of material lost in the barrel; otherwise, there will be some black spots or flow marks in the acrylic molded parts. That is why there is a special injection molding machine that is specially made for clear molded parts. Because cleaning the barrel will cost maybe one day and waste lots of materials.

Zusatzstoffe

The use of additives in the injection molding of acrylic improves its performance. UV stabilizers prevent the adverse effects of sunlight. Plasticizers improve flexibility. Apply flame retardants where they will be needed most—in safety-critical applications.

Anti-static agents are used to minimize static charges. When adding the additives, ensure that they are well dispersed throughout the system. Check the final blend for the required characteristics.

Homogeneity

The uniformity of the material is crucial in acrylic injection molding. Spread the resin and additives evenly. Ensure that the material fed into the hopper is thoroughly blended.

When mixing the product, make sure to use a high-shear screw. Look for variations between batches. Stabilize the melt temperature. This results in fewer defects being encountered on the final parts.

What Are the Key Parameters in Acrylic Injection Molding?

Basically, when you are working with actylic mold, every small detail will affect the quality of the acrylic molded part. That is the reason why most molding companies are not professional in making injection molding acrylic parts, because there are lots of extra special equipment needed to make high-quality actylic injection molding parts. Below are some of the key parameters for acrylic molding process.

Temperature Settings

Temperature control in Acryl-Spritzguss is very important. Barrel zones are usually between 220 and 280 degrees. The temperature of the nozzle must correspond to the flow of the melt; a low melt temperature will not be able to get a high-quality clear surface; a high melt temperature will decomposite the acrylic material so that the acrylic-molded part will become yellow or dark.

Mold temperatures have an impact on part clarity. A normal mold temperature is between 40 and 70 degrees, depending on the acrylic molding wall thickness. Gradual heating helps to avoid the degradation of the material. As it is widely known, stable temperature patterns promote uniformity in quality.

It is recommended that heating elements be calibrated frequently for correct measurements.

Pressure Control

Accurate control of pressure is a key factor in preventing defects in the injection molding of acrylic parts. As for the injection pressure, it ranges from 10,000 psi to even more. Pressure retention preserves some cohesion. Check the clamping pressure to minimize flash.

Pressure ramps help to avoid a sharp increase in material consumption rates. Modify as per the viscosity of the material. Periodic checks help maintain consistent molding conditions.

Injection Speed

This is a clear indication that the speed of the injection has a direct effect on the quality of the acrylic part being produced. High speeds involve filling molds rapidly, hence the short cycle time.

Continue to monitor the screw speed to ensure an even flow. Increase speed for simplicity of geometry. Low speeds also ensure that air does not penetrate into the fuel system in large quantities.

To prevent such imperfections, it is advisable to strike a balance. Speed calibration should be done often.

Flow Rate

Flow rate plays a crucial role in acrylic injection molding. It describes how material gets into the mold. Here, adjustments depend on the part design. Check the melt flow index (MFI) to ensure that it is constant. The gate sizes should be controlled to foster a uniform distribution.

Regularly check the flow meters. This will help to achieve an even distribution of the material so as to prevent the formation of surface imperfections on the product during acrylic plastic molding.

Cooling Time

Part dimensions in acrylic injection molding depend on the cooling time. A longer cooling time ensures stability. Utilize mold temperature controllers to ensure accurate cooling.

Monitor internal mold temperatures. To fine-tune cycles, gradually shorten cooling times. Even cooling prevents warping. Another is to systematically inspect the cooling passages for obstructions.

acrylic molding

How to Design Acrylic Molds for Acrylic Injection Molding?

Precision Design

Accuracy is extremely important in acrylic injection molding. All tolerances should be in micrometers. Maintain an equal thickness of the wall in order to avoid areas of tension. CAD software should be used to draw more detailed designs. Implement cooling channels strategically.

Improve the part design

Before making acrylic molds, a DFM (Design für die Fertigung) report should be carried out to check any possible potential issues. Unlike other types of plastics, such as ABS or PP, acyrlic injection molding parts will be easy to break or crack from some corners, so inserts and ejector system design is very important. Sending the customer a completely DFM report for approval will be very helpful to reduce the further issues.

Gate Design

Gate design is one of the most important factors in making high-quality acrylic injection molding products; this is unlike other injection molding materials that could use sub-gates or banana gates.

Gate locations impact flow. The simulations should be used to validate the gate design on a regular basis. Designing to specific tolerances minimizes errors and enhances part performance.

When we work with actylic molds, side gate design is mostly used in the mold; the spure angle should be 5° to 7°. If the acrylic molding wall thickness is 4 mm or above, the spure angle should be 7°, the diameter of the main runner should be 8 to 12 mm, and the overall length of the runner should not exceed 50 mm.

For acrylic plastic injection molding products with a wall thickness less than 4 mm, the main runner diameter should be 6–8 mm. For acrylic molding products with a wall thickness greater than 4 mm, the main runner diameter should be 8–12 mm.

Mold Complexity

Mold complexity is known to have an impact on the results of acrylic injection molding. Multi-cavity molds boost productivity. Lifters and slides are used for undercut features; venting insert design for deep ribs will be better for the polishing process and reducing air trap issues.

It is vital to utilize hot runners for proper and continuous material flow. There is nothing as complex as geometry, and that is why there is a need for machining.

Think about the parting lines in cases of easy ejection. Stabilize the mold at high pressure. In addition, check molds frequently for signs of wear.

Mold Material Choice

Choosing the right steel material for molds is crucial in acrylic injection molding. Make it from hardened steel for durability. Aluminum offers faster machining for some low-surface rquriement molds. For better cooling, beryllium copper inserts can be used, especially for some deep ribs.

Since most acrylic injection molding products will be completely clear and high gloss, or semi-clear and high gloss, cavity steel selection will be important; it needs easy polishing high gloss steel; mostly we use S136 or NAK 80 for actylic injection molds. Those two steels are the most popular mold materials for acrylic resin.

Thermal conductivity should correspond to the need for cooling. Material testing helps in determining the durability of the material used in construction.

Oberflächenfinish

Surface finish in acrylic injection molding plays a key role in determining overall part quality. Polished acrylic molds enhance clarity. Textured surfaces hide imperfections. Diamond polishing is best utilized for applications requiring a glossy finish. Implement electroplating for durability.

Ensure consistent mold maintenance. Control injection parameters for smooth finishes. Regularly inspect surface conditions.

 

Besonderheit Precision Design Mold Complexity Materialauswahl Oberflächenfinish
Key Focus Dimensional Accuracy Multi-cavity, Inserts High-temp Alloys Hihg gloss Polishing, Texturing
Toleranzen ±0.01 mm Variable Hitzebeständigkeit Smooth, Matte
Design Software CAD/CAM CAD, CAE Material Specs CAD for Textures
Kühlkanäle Conformal Cooling Advanced Layout Cooling Efficiency Min. Warpage
Injection Points Balanced side Gates Hot/Cold Runners Material Flow No Defects
Cost Considerations Tooling Cost High Complexity Material Cost High Gloss polishing Cost
Produktionsvolumen High-volume Runs Low to High Volume Batch Sizes Consistency

Table on How to Design Acrylic Molds for Acrylic Injection Molding!

acryl formen

What Are the Best Practices for Acrylic Injection Molding Process?

Setup Calibration

In acrylic injection molding, it is very important to set up the calibrations correctly. Set the injection pressure according to the type of material to be used. Specifically, set barrel temperatures in the range of 220 to 290 degrees. Make sure the mold clamping force matches part sizes and shapes.

Turn the injection nozzle accordingly to achieve the best flow rate. Verify the cooling time settings. Daily or frequent calibration reduces defects and helps in achieving the best results.

Process Stability

Process stability is highly important to maintain in acrylic injection molding. Monitor barrel temperatures continuously. It is crucial to maintain a constant injection pressure during the cycle. Use consistent screw speeds. Keep cooling times uniform.

Before using the molds, check for any signs of wear and misalignment. This means that stable processes result in higher-quality parts and lower scrap margins.

Variable Monitoring

Controlling variables in acrylic injection molding helps one achieve quality products. Keep track of the melt flow index (MFI) in order to ensure consistency. Record the injection and holding pressures. Monitor mold temperatures. Ensure uniform cooling rates.

It becomes important to log cycle times for each batch. Check the data for consistency and variations. It is observed that accurate monitoring assists in achieving improved efficiency in the process.

Consistency Checks

Consistency checks need to be done when it comes to acrylic injection molding. Check that the wall thickness of the parts under consideration is uniform. Measure the dimensional accuracy regularly. Check for its optical clarity in the transparent section.

Check for the absence of surface defects. Carry out the tensile strength test after some time. Document all findings meticulously. This is a mere check to ensure that the manufacturing results are accurate.

What Role Does Cooling Play in Acrylic Injection Molding?

Cooling Importance

Cooling plays a significant role in acrylic injection molding. It ensures one-dimensional stability. Correct cooling helps to avoid warping, air bubbles, and shrinkage. Uniform cooling improves surface texture. Cooling channels in acrylic molds help to regulate the temperature.

The use of effective cooling preserves material characteristics. Supervision of the cooling phases enhances product quality. Effective heat dissipation is essential.

Effective Techniques

Efficient cooling methods improve acrylic injection molding. Employ conformal cooling channels to ensure an equal distribution of heat. Use a water- or oil-based cooling system. Monitor coolant flow rates. Use baffles and bubblers for complex molds.

Regularly maintain cooling circuits. Maximize the channel locations for effective heat dissipation. Repeatable processes improve part consistency.

Cooling Time

Cooling time is one of the critical parameters that has a direct impact on the efficiency of acrylic injection molding. Longer cooling allows the part dimensions to become stable. Accuracy results in the minimization of cycle time. The cooling should be adjusted depending on the thickness of the part.

The temperature of the mold should be monitored throughout the process. Maximize cooling cycles to increase efficiency. Regular cooling times help to eliminate the formation of defects. Regularly calibrate cooling equipment.

Cycle Efficiency

The overall cycle time in Acryl-Spritzguss highly depends on the cooling process. Rapid cooling reduces the time taken to complete a cycle. Effective means of cooling increase capacity. Coordinate cooling with mold filling and packing.

Thermal imaging should be used to monitor efficiency. Coherent cycles contribute to increased overall production rates. Regularly review cycle parameters to improve acryl formen.

Temperature Control

Temperature regulation is very important in the cooling process of acrylic injection molding. Maintain consistent mold temperatures. Temperature controllers should be used for good regulation.

Ensure the coolant temperature is stable. Modify settings using the properties of the material being cut.

Introduce the necessary sensors for real-time monitoring. Constant temperatures avoid conditions like thermal stress. It is for this reason that the application of consistent control leads to quality parts.

acrylic plastic molding

acrylic plastic molding

How to Optimize Acrylic Injection Molding for High Precision?

Präzisionstechniken

Another advantage of the process is the precision of the injection molding of acrylic, resulting in high accuracy. Use CNC-machined molds for high tolerance. To continue the flow, use hot-runner systems. For dimensional stability purposes, perform controlled cooling.

Regularly calibrate injection parameters. Accurate screw and barrel designs must be employed. To ensure proper traffic distribution, it is crucial to identify the optimal positions of the gates. Regular inspection ensures precision.

Automation Use

The use of automation in the manufacturing process increases accuracy in the injection molding of acrylic. Use robotic arms for the handling of the parts. Employ automated quality inspection systems. Adopt the use of automated material feeding systems.

Make use of real-time process monitoring software. Automation reduces human error. Standardization of production schedules enhances precision. Indeed, the reliability of automation systems is achieved through regular maintenance of the automation systems.

Sensor Integration

Integration of sensors in acrylic injection molding enhances accuracy. It is recommended to install temperature sensors for better control of heat. Use pressure sensors to record injection force. Use flow sensors to ensure a constant rate of material flow.

Install sensors within mold cavities to collect real-time data. Monitor sensor data continuously. Modify the parameters in response to the feedback received. The accuracy of sensors enhances process control.

Process Refinement

The fine-tuning of the process enhances the accuracy of the injection molding of acrylics. Increase the injection speed and pressure parameters. Tweak cooling times for stability. Perform process changes in the simulation software. Ensure that process parameters are reviewed and updated as necessary.

Use feedback loops for the purpose of ongoing modification. Characterize data for perspective: defect analysis. Process refinement reduces variability.

Continuous Improvement

To have precision in acrylic injection molding, there is a need to constantly improve. Implement Six Sigma methodologies. Training of operators should be conducted frequently. Make statistics-driven recommendations on how things can be done better.

Perform compliance tests frequently. Proactively promote quality. Document all improvements. Sustained high precision can only be achieved if there is constant improvement.

Schlussfolgerung

All in all, to achieve a high level of precision in acrylic injection molding, which requires professional acrylic molding companies, the basic injection molding process is pretty much the same as for other materials; even small details will affect the quality of the final acrylic molded part. Use these techniques for better outcomes.

If you have acrylic mold requirements, welcome to contact us. Sincere Tech is one of the top 10 Kunststoff-Spritzgussunternehmen in China, offering acrylic molding, Umspritzen, Einsatzspritzguss, and any other custom injection molding products.

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PMMA-Spritzguss

Acrylboxen

What Means PMMA-Spritzguss

PMMA injection molding, acrylic injection molding, or polymethyl methacrylate molding is a process where organic glass or acrylic is injected into an injection mold cavity to mold a particular product upon cooling and hardening. The PMMA-Spritzguss parts are normally used to make some transient components or parts, such as car windows, LED lenses, display boxes, and LED screens for some electric appliances. Acrylic is preferred to glass because it has better abrasion resistance. Spritzguss PMMA has excellent light transmission properties compared to all the other plastic materials in the world today, making it an ideal material for applications where clarity is essential. Additionally, there are lots of thin-walled, clear plastic parts that select PMMA as the molding material.
PMMA-Spritzguss

PMMA Injection Molding Technology

PMMA is the highest transperant plastic materils but PMMA is easy to break comparing to PC or ABS, so PMMA’s modification appears one after another such as copolymerization between methyl methacrylate and styrene and butadiene, a blend of PMMA and PC, etc. 372 PMMA is the copolymer of methyl methacrylate and styrene. If you add a small amount of nitrile rubber (about 50%) in the 372 PMMA, it will become 373 PMMA.

The fluidity of injection molding PMMA is poorer than that of PS, ABS and its melt viscosity is rather sensitive to the change of temperature. In molding, it changes the melt viscosity mainly from the injection temperature. PMMA is an amorphous polymer, the melt temperature is above 200 Celsius degree and the decomposition temperature can reach 270 Celsius degree.

  1. Processing of plastic
    PMMA plastics has a certain degree of water absorption of 0.3-0.4%. The injection molding PMMA moisture must be less than 0.1%. Typically, it is 0.04%. The presence of moisture causes bubbles, gas lines, and low transparency. So it should be dried. Dying temperature is 80–90 degrees Celsius, and drying time is 3 hours or more. In some cases, the utilization of recycled materials can reach 100%. The actual quantity depends on the requirements for quality. Usually, it can reach 30%. You should make sure there is no pollution of recycled materials, or it will influence the transparency and nature of the finished products.
  2. Auswahl einer Spritzgussmaschine
    The Injection molding PMMA material doesn’t have special requirements for the injection molding machine. Due to the great melt viscosity, it requires the grooves to be deeper and the nozzle hole to have a larger diameter. If you need products with higher strength requirements, you should use a larger aspect ratio of the screw to implement low-temperature plastics. In addition, PMMA molding resin must use a drying hopper to store material.
  3. Gestaltung von Form und Anguss
    PMMA injection Mold temperature can be 60–80 °C. The diameter of the sprue should match the internal taper. The optimum angle is 5 to 7. If the wall thickness of injecting molding products is 4 mm or more, the angle should be 7, the diameter of the mainstream channel should be 8 to 10 mm, and the overall length of the gate should not exceed 50 mm.
    For PMMA injection molding products with a wall thickness less than 4 mm, the diameter of the flow channel should be 6–8 mm. If the PMMA wall thickness is more than 4 mm, the diameter of the flow channel should be 8–12 mm. The depth of the fan-shaped and tab-shaped gates should be 0.7 to 0.9 t (t is the wall thickness of the product), and the diameter of the pin gate should be 0.8 to 2 mm. Injection molding PMMA Products with lower viscosity should choose the smaller size. The common venting hole’s depth is 0.05 to 0.07 mm, its width is 6 mm, the stripping slope is 30′-1, and the and the cavity portions are between 35′-1 and 30.
  1. Schmelztemperatur
    You can use the air injection method to measure temperatures ranging from 210 to 270 degrees Celsius, which depends on the information provided by the supplier.
  2. Injection temperature
    You can use rapid injection to avoid generating a high degree of internal stress when work with PMMA injection molding material. It’s suitable to use multi-level injection, such as slow, fast, slow, etc. When injecting the thick parts, you should use a slow speed.
  3. Verweilzeit
    If the temperature is 260 degrees Celsius, the dwell time is within 10 minutes. If the temperature is 270 degrees Celsius, the dwell time is within 8 minutes.

Acryl-Spritzguss

Applications of PMMA Plastic Injection Molding

There are many industries that need PMMA injection molding parts. Below are a few components that use injection molding PMMA parts:

  1. Eyeglass lenses: PMMA is one of the best materials for eyeglasses due to its excellent optical properties. It has the highest transparency of all other plastic materials, PMMA injection molding making it the best choice for eyewear.
  2. Plexiglass windows: PMMA, also known as plexiglass or acrylic glass, is a popular alternative to traditional glass windows due to its high impact resistance and optical clarity. It is commonly used in buildings, aquariums, and even airplane windows.
  3. Mobile phone casings: PMMA is used in the manufacturing of mobile phone casings due to its high impact resistance, scratch resistance, and optical clarity. It is also lightweight and can be easily molded into various shapes and sizes.
  4. Computer and electronics casings: Similar to mobile phone casings, PMMA is used in the manufacturing of computer and electronics casings due to its durability, impact resistance, and optical clarity. It is also lightweight and can be easily molded into various shapes and sizes.
  5. Vehicle windshields: PMMA is commonly used in the manufacturing of vehicle windshields due to its high impact resistance and optical clarity. It is also lighter than glass, which can improve fuel efficiency.
  6. LED lens: You see the light on the street and your house; that small lens inside is made of PMMA injection molding parts. This is very popular in the light industry.
Below the acrylic injection molding part we made before. If you have any project that needs PMMA molded products, feel free to send us your data, and we will offer you the best quality with our expert experience in PMMA injection molding service.
Spritzguss PMMA

Spritzguss PMMA

Advantages of PMMA injection molding (acrylic injection Formen)

1. It produces scratch-resistant products.

Research has confirmed that Acryl-Spritzguss materials are more scratch-resistant than other glass products. In this manner, the molding process generates products that can maintain their lustrous appearances for a long without degradation.

2. It produces light transperant products.

The biggest feature of PMMA injection molding is its high transparency, with a light transmittance of 92%, which is the best light transmittance among plastics. density is 1.185 grams per cubic centimeter. On the other hand, glass has a density of 2.4 grams per cubic centimeter, the highest light transmittance of glass is 91%. As a result, PMMA injection molding products that can be used as lightweight alternatives to glass.

3. PMMA injection molding can produce complex designs.

Injection molding develops advanced shapes that cannot be generated by other injection molding processes, such as metal injection molding. Furthermore, the PMMA injection molding process can reproduce a significant number of products that are identical in terms of shape, size, and weight.

4. High Production Efficiency

Die PMMA-Spritzguss process is faster than metal injection molding. As a result, more production units can be produced through this process in a given amount of time. Technical analyses have confirmed that PMMA injection molding plants have shorter cycle times, which increase the overall production output of the industry.

5. Enhancement of Color Flexibility

Acryl-Spritzguss produces items that can be mixed with resins to create a wide variety of colored products. In contrast, this feature is not present in other processes, such as metal or glass injection molding.

6. Special material for high requirements of transparent plastic molding.

PMMA material called Acryl, or plexiglass, has a transmittance of up to 92%, which is higher than glass. That means klare Acrylbox molding is one of the best options for high-requirement transparent injection molding parts, such as glass, optical glass, lenses, car lights, transparent pipes, etc.

Custom Acrylic case

Disadvantages of Acrylic PMMA Plastic Injection Molding

Like any other molding manufacturing process, it has its own set of disadvantages that must be taken into consideration. Below are some of the disadvantages of acrylic PMMA plastic injection molding.

  1. The materials produced have a lower resistance to impact compared to those produced by Metallspritzguss.
  2. The heat resistance of most products produced by the PMMA injection process is low (about 80 degrees Celsius).
  3. Most items produced by the process have lower mechanical strengths, which limit their loading capacities.
  4. Some acrylic products have poor chemical resistance, which makes them prone to reacting with organic compounds.
  5. PMMA injection molding needs to invert the special injection mold, which means the initial tooling cost is high. This is not beneficial for low volumes of production.
  6. Limited design flexibility. The process is best suited for producing products with simple and uniform shapes. Complex designs with intricate details may be difficult to achieve using acrylic PMMA plastic injection molding. This limitation can be a significant drawback for manufacturers looking to create unique and innovative products.

Tips to make high quality PMMA injection molding parts.

Making PMMA injection molding parts is a little different than other injection molding parts because, mostly when we make PMMA molded parts, we will make high-glass PMMA parts. In that case, some special equipment is needed, especially for some thick wall PMMA injection molding parts. Below are some tips for you to make high-quality PMMA injection molding parts.

Mold design

Since PMMA is a transmission material, any flow marks will be easy to see, and this could be an issue as well. Using moldflow analysis, it will be very important to check where the best gate location is. Once the gate location has been determined, the gate shape is important as well. Mostly,  we suggest designing a side gate or fan gate, which will make it easier to fill the cavity and avoid the flow marks.

The injection molding machine and the hot water tank are in use.

If you are making thick-wall PMMA injection molding parts, then you will always have sink and bubble issues because plastics have a shrinkage rate. The thicker the wall, the higher the shrinkage rate, so there will be bubbles inside the parts, no matter how long the cooling time is, and when you use a long cooling time, the cycle time will be increased as well, which will increase the cost.

In that case, a hot water tank can improve these issues. Use 60–80 degree temperature water in the water tank. Once you pick the PMMA injection molding parts from the mold cavity and put them into the hot water tank for 6–12 minutes,  you take out the molded parts, so the sink and bubble issues will be greatly improved.

Making high-quality PMMA molding parts is not an easy task. If you have a project that needs PMMA molding parts, finding a professional PMMA injection molding contractor is very important. This will make sure your project is successful or not.

Schlussfolgerung
Given the above points, it is essential to understand how PMMA injection molding works, its applications, advantages, and disadvantages. Also, knowledge is vital in helping you appreciate the PMMA injection molding process.
If you want to see more transparent plastic molding parts, please go to our transparentes Kunststoffformteil page. If you have any project that needs aus PMMA injection molding or any other kundenspezifische Acrylbox mold and molding parts, you are welcome to send us an email, We have been working with PMMA injection molding parts over 12 years and solved lots of PMMA molding issues.
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