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Design principles for the runner system:

1. For the single plastic part and multiple cavities, the balanced runner (except special) should be used, that is, the position of each cavity gate and the size of the gate point are the same and the length of the runner is the same. To ensure uniform molding conditions in each cavity.

2. For multi products and multi cavities use non-equilibrium runner and gate point, the size of the nozzle or runner should be adjusted according to the distance of the flow to ensure that the cavities are filled as much as possible.

3. In order to reduce heat and pressure loss, the runner should be as short and straight as possible, and the radius should be added at the corner to ensure smooth flow. The surface of the runner must be polished with more than 600# sandpaper. If the part is mirrored, the runner must be polished with 1000# sandpaper.

4. The gate system should be designed cold slug well to prevent cold material entry into the cavity and affect the quality and appearance of the parts.

5. The gate system must be vented to ensure that the plastic melt fills all corners of the cavity, so that the cavity gas can be discharged smoothly.

6. The gate system should be able to prevent the plastic parts from shrinking mark, deformation, dimensional deviation and other defects. The gates are convenient to cutoff or cut automatically and do not affect the appearance of the product.

7. In order to improve the mass production efficiency, it is necessary to minimize the subsequent processing of the plastic parts when designing the gate. Automated mass production, when the gate is taken out, the robot is used as much as possible to shorten the cycle time.

8. For the plastic injection molding gate design, the diameter of the root should be no smaller than the runner. For materials with high brittleness such as PS, a double-sided 3° draft angle should be used. Preventing the breakage of the sprue and runner, while the runner breakage will cause trouble for mass production.

9. Making runner into a circular or U-shaped that is easy to process.

10. The design of the gate system should take into account the amount of runner material. To save costs and eliminate waste, the weight of the runner is controlled below 25% and cannot exceed 50% (special consideration for special parts).

11. When there are multiple injection points on a product, the influence of the size and position of the welding line on the strength and appearance of the product should be considered.

12. For a multi-cavity plastic mould, reasonable, symmetry and compact positioning is able to prevent the eccentric load, reduce the mold base dimension and the tonnage of the molding machine.

13. For a multiple products mould which is also called family mold, the size of the gate must be adjusted according to the plastic parts dimension to ensure that each product is filled simultaneously.

14. For the complicate product, it's necessary to make mold-flow analysis to help design a good runner system and gate position.

Design standard for Sprue:

1.Injection molding machine nozzle and sprue matching

The spherical surface SR of the mold sprue should be 1-2MM larger than the nozzle SR of the injection molding machine. The SR of the nozzle can be found in the specifications of the injection molding machine.

Attention: When designing the mold, check the length of the nozzle of the molding machine that can be inserted into the mold. Should make proposal if have to use the extended nozzle.

2.Sprue diameter ⌀D setting

The sprue D should be 0.5mm larger than the the nozzle of the injection molding machine.

3.To shorten the sprue, we have to:

A.For two plate mould, sprue should be sunk in to the A plate (except for special customer requirements).

B.For three plate mould, big spue bush is must if the sprue length is 25mm or more.

C.Plastic parts with appearance requirements and other special requirements use hot sprue.

Design standard for Runner:

1.Type of runner.

A.Round runner.

B.U shape runner.

2.D series: 2 2.5 3 3.5 4 4.5 5 6 7 8 (10 12 reference use)

3.The runner diameter setting

For PE, PA, the diameter can be small. For PC, PMMA, the diameter value can be a large value.

Estimation diameter according to experience

4.Precautions

A.In the U-shaped runner, the size of the runner can be changed by

adjusting the H value.

B.Use round runner whenever possible

C.The runner must be thicker than the section of the subordinate

runner (see table below), if the secondary runner increases,

D1 diameter can be reduced according to the actual situation.

Design principles for common gates:

The form, position, size and number of nozzles should fully meet the requirements of mold processing and parts production.

1.Direct gate

1. Low pressure loss, easy to fill
2. The pressure at the gate is large, which will cause deformation.
3. It is difficult to remove the nozzle
4. Common gate
5. Easy mold processing
6. Correction is easy
7. Thin and long barrel products should not be used.
8. It is necessary to take care that whether the subsequent processing of the nozzle is convenient and whether the residue after processing will affect the appearance and function of the product.
9. Pin point gate
10. Flexible to select the gate location.
11. Small residual stress near the gate
12. After the mold is opened, the gate can be pulled off by itself. The traces left on the plastic part are not obvious, and the appearance of the surface of the plastic part is not affected.
13. The flow rate of the molten plastic flow through the gate is increased, and the frictional force acts to increase the temperature of the plastic stream. In this way, a plastic part with a clear shape and a glossy surface can be obtained.
14. Injection pressure loss is large, which is not good for plastic molding.
15. The mold structure is more complicated, and the double parting line mold (three plate mold) is generally used to remove the sprue.
16. Because the high flow velocity near the gate, the molecules are highly oriented, and local stress is increased, which may cause cracking. Therefore, without affecting the function of the plastic part, increase the wall thickness of the plastic part opposite the gate.

H.Warpage wil occur when a large plastic part adopts a point gate, so multiple point gates should be used at

the same time.

4. Sub-gate
5. Gate can be located inside or outside of the plastic product, the gate is usually located at the bone position of the injection molded product, the gate is concealed and does not affect the appearance of the injection molded part.
6. Small gate mark.
7. Gate is cut automatically.
8. There is a problem of large pressure loss.
9. Large flow resistance.
10. Fan gate
11. Good liquidity.
12. Can be evenly filled to prevent deformation of plastic parts.
13. The plastic parts look good.
14. Gate is not easy separate.
15. Large gate residue
16. Suitable for large and thin-walled plastic parts.

Slug well design

The location of the slug well is generally designed at the end of the sprue and runner.

That is, the first place where the melt plastic arrives, and venting is must added.

The design of the slug well varies depending on the different gate type.

Ejection of sprue

Normally, designer should have a thorough understanding of material properties, choose the most suitable solution.

HanKing Mould Enginering Ltd. started the business in the year of 1996 as a injection mold maker company in the line of mold making and injection molding in Longgang, Shenzhen, China. With continuous developments and progresses, we have become a professional Chinese plastic injection tooling company, offering custom plastic injection molding service, plastic molding manufacturing and other mould making services.

Following the concept of customer first, HanKing Mould dedicates to be a trustworthy tooling company by designing and manufacturing plastic injection molds, providing custom plastic injection molding china manufacturing and services according to every individual's requirements. Hanking's successes are ensured by our management capability, technical knowledge, advanced plastic tooling equipment and professional injection molding services. We are pursuing better quality and technical capability to meet the demands of increasing mold making markets.

Quality Assurance

Regarding quality as life, in HanKing all operations are under ISO 9001 procedure.

Owning advanced high precision test equipment, we carry out 100% inspection for the entire process, from incoming material until shipment. We have plastic injection molding quality assurance,welcome to buy our product.

Measure Equipment:

3D Measuring Machine

2D Measuring Machine

Toolmaker's Microscope

Height Gauge

Caliper

Pin Gauge

Micrometer

Others

CUSTOMER ORIENTED & CONTINUOUS IMPROVEMENT

Main QC Procedure

Customer's Mold Specification Sheet Check

Design Optimize Control

Steel Hardness Inspection

Electrodes Inspection

Core and Cavity Steel Dimension Inspection

Pre-Assembly Inspection

Trial Report and Samples Inspection

Final Full Inspection (prior shipping)

Mould Package Inspection

TQM(Total Quality Management)

FMEA(Failed Mode Effects Analysis)

SQA(Supplier Quality Assurance)

ORT(On-Going Reliability Test)

SPC(Statistical Process Control)

Six Sigma Projects

CIP(Continuous Improvement Program)

APQP(Advanced Product Quality Planning)

PPAP(Production Part Approval Process)

HanKing Mould Enginering Ltd. started the business in the year of 1996 as a china injection molding suppliers in the line of mold making and injection molding in Longgang, Shenzhen, China. With continuous developments and progresses, we have become a professional Chinese plastic injection tooling company, offering custom plastic injection molding service, plastic molding manufacturing and other mould making services.

Following the concept of customer first, HanKing Mould dedicates to be a trustworthy tooling company by designing and manufacturing plastic injection molds, providing custom plastic molding china manufacturing and services according to every individual's requirements. Hanking's successes are ensured by our management capability, technical knowledge, advanced plastic tooling equipment and professional injection molding services. We are pursuing better quality and technical capability to meet the demands of increasing mold making markets.

1. Process analysis of plastic products.

Before the die design, the designer should fully analyze whether plastic products conform to the principle of injection molding. It is necessary to consult with the designer carefully and reach a consensus. It includes the necessary discussion of the geometric shape, dimensional accuracy and appearance requirements of the products, and avoids the unnecessary complications in injection mold building as far as possible.

2. Design of die structure.

A set of high-quality die not only needs good processing equipment and skilled injection mold builder but also a very important factor is to have good die design, especially for complex dies, the quality of die design accounts for more than 80% of the quality of the die. Excellent die design is: on the premise of meeting the customer's requirements, the processing cost is low, the processing difficulty is small, and the processing time is short.

3. Determining die materials and selecting standard parts.

In the selection of die materials, besides the accuracy and quality of products, the correct selection should be made according to the actual ability of processing and heat treatment in the dying factory. In addition, in order to shorten the manufacturing cycle, the existing standard parts should be used as much as possible.

4. Part processing and die assembly.

In addition to giving the best structure and reasonable tolerance coordination in the design of the precision of the die, parts processing and die assembly is very important. Therefore, the selection of processing accuracy and methods plays an absolute leading role in die manufacturing.

Therefore, in order to reduce injection mold building error, first of all, the processing accuracy should be improved. With the use of CNC machine tools, this problem has been well controlled. In addition, in order to prevent the errors caused by the wear and deformation of the die, quenching treatment should be applied to the key parts such as the cavity and core of the die when the processing precision is high and the output of the product is high. In order to save material and facilitate processing and heat treatment, the mosaic structure should be adopted in die design.

In order to solve the errors caused by uneven shrinkage and inconsistency between pre-contraction and actual contraction, the product tolerance of 1/3 is generally selected as injection mold building tolerance in injection mold building. The purpose is to leave greater room for adjustment in the later forming process, so as to solve the errors caused by the forming process.

5, model test.

A set of molds starts from design to assembly, only 70% to 80% of the whole manufacturing process is completed. For the errors caused by the inconsistency between pre-contraction and actual contraction, the smoothness of demoulding and the cooling effect, especially the influence of gate size, position, and shape on the accuracy and appearance of products, it must be checked by test mold. Therefore, die testing is an indispensable step to check whether the die is qualified or not and to select the best forming process.

HanKing Mould Enginering Ltd. started the business in the year of 1996 as a china plastic injection mould manufacturers in the line of mold making and injection molding in Longgang, Shenzhen, China. With continuous developments and progresses, we have become a professional Chinese plastic injection tooling company, offering custom plastic injection molding service, plastic molding manufacturing and other mould making services.

Following the concept of customer first, HanKing Mold dedicates to be a trustworthy tooling company by designing and manufacturing plastic injection molds, providing custom plastic molding china manufacturing and services according to every individual's requirements. Hanking's successes are ensured by our management capability, technical knowledge, advanced plastic tooling equipment and professional injection molding services. We are pursuing better quality and technical capability to meet the demands of increasing mold making markets.

BMC/SMC plastic Moulding Description:

We mainly use injection molding and pressure molding as the methods. When designing the flow channel and parting surface,  we think that the cavity pressure should be as small as possible, especially some small ribs, as well as the smooth exhaust, the discharge position, shape, and material flow direction, which would all be fully considered. And the active exhaust must be complete with an overflow. We guarantee the appearance and strength. With the Vacuuming structure, the mold temperature balance is consistent as the appearance and strength of the product shall be guaranteed as well.

BMC/SMC injection molding Features:

high insulation, chemical resistance, high fire resistance, good water resistance, accurate size, stable working performance, light weight, high strength, acid and alkali resistance, waterproof, moisture-proof, low energy consumption, no waste, no need to clean the mold cavity, mold The temperature is stable, the temperature difference is small, the breakage is short, poor appearance is less, and the efficiency is high.

About BMC/SMC Moulding：

The basic process of the compression molding process is to place a certain amount of the pre-treated molding material into a preheating compression mold, and apply a higher pressure to fill the mold cavity with the molding material. Under the predetermined temperature conditions, the molding material is gradually solidified in the cavity, and then the SMC product is taken out from the stamper, and the necessary auxiliary processing is performed to obtain the final product.

The SMC molding process of the composite molded product is a process of solidifying into a product in a cavity after the binder is loaded or heated under the condition that the curing agent is present or heated. Molding temperature, molding pressure and mold exhaust, temperature balance, and mold structure all affect the quality of SMC products. It is necessary to determine the best solution under the consideration of various influencing factors.

BMC is the initial abbreviation of English Bulk Molding Compound, and the Chinese name is a group molding compound. Pre-mixed into a paste by unsaturated polyester resin, low shrinkage/low profile additive, initiator, internal mold release agent, mineral filler, etc., and then added thickener, colorant, etc., with different lengths of glass fiber, in special Stirring in the kettle is carried out to carry out a thickening process, which finally forms a dough-like intermediate material which can be used for molding and injection molding.

The bulk molding compound manufacturing process basically follows the same rules as the injection mold. However, SMC and BMC molds also have different characteristics from injection molds, such as flow path, exhaust, heating, cavity pressure and balance, parting structure, mold steel used and precision, shrinkage and injection molds. Differently, the BMC mold is molded at a high temperature, and the plastic mold is molded at a normal temperature.

SMC BMC molds require heating rather than cooling systems. The temperature of the mold is usually between 130 and 160. It is very important to keep the temperature of the mold and the exhaust gas when designing the mold. The mold is easier to fill, the product is not easy to be deformed, and the surface is better. Commonly used heating systems are steam, oil and electric heating rods.

Vacuum assisted systems for BMC injection moulds and SMC molds: Products with Class A surfaces are usually vacuum-assisted, and the internal cavity and vacuum insulation of the mold are very important. The mold must have a sensor and a vacuum system to measure the mold temperature and pressure vacuum. Production SMC and BMC molds must guarantee high quality, long life and economy. As one of the most professional sheet molding compound suppliers  in China, Aobang Technology Co., Ltd.'s years of experience in the production of SMC and BMC molds and proficiency in machine, mold, material and process can ensure the maximum benefit of customers.

Zhejiang Aobang Technology Co., Ltd., established in 2010, is a backbone enterprise that manufactures composite moulding at home and abroad. We sincerely hope to establish long-term and strong partnership with domestic and foreign businesses and business circles. We hope to gain recognition and support from our customers and to develop mutual cooperation.  Just feel free to contact us!

What is a Mold?

In industrial production, various types of presses and special tools mounted on the press are used to produce metal or non-metal materials into parts or articles of the desired shape by pressure. This special tool is collectively referred to as a mold, and the material of the mold is generally divided into Plastic injection moulding service also has the formation of sheet metal steel molds.

We have the world's leading 3D printing, CNC machining, vacuum complex molding, low pressure infusion, injection molding and other equipment, rich production experience can provide you from product design to prototype verification, rapid mold manufacturing to small batch trial production, mass production Dragon service. With more than 20 years of experience in mold manufacturing, the industry covers electronics, automotive, electrical machinery, instruments, electrical appliances, home appliances, communications and other fields. The mold design is accurate, the product is corrosion-resistant, has good strength and long service life, and can provide you with professional injection molding. Rapid mold manufacturing services such as mould design services, blow molds, extrusion molds, silicone molds, and die-casting molds help your products increase production efficiency, save development costs, and speed time-to-market for new products. You only need to provide us with the design drawings, and our professional image analysts will carry out processing feasibility analysis and design optimization for your drawings.

If you are looking for a professional and reliable service provider that can provide you with rapid mold manufacturing?Please contact our professional team at info@duchgroup.com or contact us using the inquiry form on this website, we will provide quotes and suggestions free of charge.

Duch Group Provides customers with competitive solutions such as rapid prototype service china, mass production, small batch production, 3D printing, mold making, and injection molding. With more than 20 years of extensive production experience in the rapid prototyping industry, it is the world's largest rapid prototyping service company.

Material Description: Acrylic plastic is commonly known as plexiglass, resistant to outdoor aging. It has excellent light transmission and good surface finish, and can print transparent and translucent products with certain strength requirements.

The disadvantage is that the surface hardness is slightly lower and it is easy to scratch.

Application: pmma injection molding is widely used in automotive lighting signs, door glass and lamp glass covers, also be used to model teeth for orthodontic treatment. Suitable for parts with transparent insulation and low strength requirements.

Production process: Injection Molding, CNC Machining

Cases

Student Graduation Design Case Study of Expressway Inspection & Emergency Treatment Engineering Vehicles

According to the renderings and 3D model data provided by the customer, select the appropriate production process, the surface is finely processed and delivered on time.

Fitness Equipment Case Study

After analysis, it was found that the product was the appearance model, the adhesion of the final product’s rubber paint should be considered.

Mask Model Case Analysis

This project is mainly made by hot runner technology.hot runner is used in injection molds,a heating assembly system that injects molten plastic particles into a cavity of a mold.

Analysis of CNC Machining Case of Great Wall Automobile Hood Analysis of CNC Machining Case of Great Wall Automobile Hood

According to the provided 3D model data and specific production requirements, strictly control the quality to ensure that the production parts are matched with the real car.

Duch Group Provides customers with competitive solutions such as cnc prototyping china, mass production, small batch production, 3D printing, mold making, and injection molding. With more than 20 years of extensive production experience in the rapid prototyping industry, it is the world's largest rapid prototyping service company.

BMC/SMC Moulding Description:

We mainly use SMC injection molding and pressure molding as the methods. When designing the flow channel and parting surface,  we think that the cavity pressure should be as small as possible, especially some small ribs, as well as the smooth exhaust, the discharge position, shape, and material flow direction, which would all be fully considered. And the active exhaust must be complete with an overflow. We guarantee the appearance and strength. With the Vacuuming structure, the mold temperature balance is consistent as the appearance and strength of the product shall be guaranteed as well.

SMC/BMC Mould Features:

high insulation, chemical resistance, high fire resistance, good water resistance, accurate size, stable working performance, light weight, high strength, acid and alkali resistance, waterproof, moisture-proof, low energy consumption, no waste, no need to clean the mold cavity, mold The temperature is stable, the temperature difference is small, the breakage is short, poor appearance is less, and the efficiency is high.

About BMC/SMC Moulding：

The basic process of the compression molding process is to place a certain amount of the pre-treated molding material into a preheating compression mold, and apply a higher pressure to fill the mold cavity with the molding material. Under the predetermined temperature conditions, the molding material is gradually solidified in the cavity, and then the SMC product is taken out from the stamper, and the necessary auxiliary processing is performed to obtain the final product.

The pressing process of the composite molded product is a process of solidifying into a product in a cavity after the binder is loaded or heated under the condition that the curing agent is present or heated. Molding temperature, molding pressure and mold exhaust, temperature balance, and mold structure all affect the quality of SMC products. It is necessary to determine the best solution under the consideration of various influencing factors.

BMC is the initial abbreviation of English Bulk Molding Compound, and the Chinese name is a group molding compound. Pre-mixed into a paste by unsaturated polyester resin, low shrinkage/low profile additive, initiator, internal mold release agent, mineral filler, etc., and then added thickener, colorant, etc., with different lengths of glass fiber, in special Stirring in the kettle is carried out to carry out a thickening process, which finally forms a dough-like intermediate material which can be used for molding and injection molding.

The BMC injection molding process basically follows the same rules as the injection mold. However, SMC and BMC molds also have different characteristics from injection molds, such as flow path, exhaust, heating, cavity pressure and balance, parting structure, mold steel used and precision, shrinkage and injection molds. Differently, the BMC mold is molded at a high temperature, and the plastic mold is molded at a normal temperature.

SMC and BMC molds require heating rather than cooling systems. The temperature of the mold is usually between 130 and 160. It is very important to keep the temperature of the mold and the exhaust gas when designing the mold. The mold is easier to fill, the product is not easy to be deformed, and the surface is better. Commonly used heating systems are steam, oil and electric heating rods.

Vacuum assisted systems for BMC and SMC molds: Products with Class A surfaces are usually vacuum-assisted, and the internal cavity and vacuum insulation of the mold are very important. The mold must have a sensor and a vacuum system to measure the mold temperature and pressure vacuum. Production SMC and BMC molds must guarantee high quality, long life and economy. Aobang Technology Co., Ltd.'s years of experience in the production of SMC and BMC molds and proficiency in machine, mold, material and process can ensure the maximum benefit of customers.

Zhejiang Aobang Technology Co., Ltd. is one of the most professional sheet molding compound manufacturers in China, and we hope to gain recognition and support from our customers and to develop mutual cooperation.