Plastic Injection Molding Manufacturer CNMOULDING Benefits Clients by Cutting Sales Costs

By taking advantage of Internet, CNMOULDING gets the edge in supplying the most cost-effective plastic injection molding products to customers from all over the world. Now CNMOULDING is providing an array of first-class products and services in automotive, home appliances and electronics

SHANGHAI, China, August 30, 2015  -- Plastic injection molding products has been widely used in many industries and CNMOULDING promises customers direct benefits through its easy and definitive consumer approach module. The company's objective to become the "one stop shop" is facilitated through its 2000 sq meters workshop in China.  Powered by world-class infrastructure, a large and adroit workforce and a solid management team, the company has become a trusted supplier of plastic molds for many European and North American based companies. Furthermore, CNMOULDING claims to be the only China plastic molding injection company that offers complete cost analysis and full transparency to prospective buyers.

Company insiders indicate that the biggest plus of working with CNMOULDING is in the direct method of approach that the company adopts. As a top plastic injection molding manufacturer, CNMOULDING has earned its fame though innovation, quality control and cost-down.  According to their reports, CNMOULDING picks up direct consumer leads from the Internet and then tries to establish direct contact. Company officials have also, on several occasions, shown why the conventional way of marketing through trade shows is becoming obsolete. The company plans further expansion and the owners indicated that they are bringing more innovation in the manufacturing process to accelerate production and reduce downtime.

CNMOULDING has also made an elaborate effort to keep their price structure transparent for their international clients. While most similar companies would make every effort to conceal the numbers, CNMOULDING promises to give their clients a sneak peek into the pricing and profit structure.

The managerof CNMOULDING recently addressed the local press. He laid great emphasis on the sales team of the company: "Most companies tend to carry out their sales through salespersons who exhibit an acute lack of product knowledge. At CNMOULDING, our sales manager deals with all the sales and effectively communicates the messages in and out of the company. We also make it a point to adhere to transparent pricing."

About the company

CNMOULDING is a leading direct plastic injection company based out of China. The company caters to both the Chinese and international markets.

More information about the company is available at 

www.plastic-injectionmoulding.com  

About CNMOULDING

Shanghai CNMOULDING TECHNIC CO.,LTD , CNMOULDING offer plastic injection molding service and specializes in various plastic moulds for. automotive, home appliances, electronics ,as well as general industrial OEM applications. Our company covers an area of more than 2000 square meters workshop, surrounded with convenient  transportation . At present, our group reaches to more than 100 employee and capital assets to more than 8 million RMB. Our capacity is 40-50 sets mould per month.

CNMOULDING’s mission is to be professional, trustworthy and creative toolmaker and injection molding supplier, We always keep Layout at the top level, introduce modernized management system, Go in for zero default. Make sure quality and techniques in the highest way. Therefore, We dedicate to make innovation and progress continually to be your better partner. enhance our technology and accumulate experience in mold building ,injection molding, print and paint  ,etc.

Why Choose Us?

1,We provide direct factory price and make cost transparent.

As you know there are more than 5000 trading companies in China, but Some of them concealed their property very well, It is hard to tell for a foreigner. normally they will take profit 30%.so we show the detail cost in our website, Most traders can’t quote the price with this level. but these price are normal price for us and have proper profit.

2,We focus on providing one stop service for small and middle size company.

We are a middle size mold making and injection molding company, it is also one reason for good price. We don’t need to pay for the huge administration fee compare to big factory. We got ISO9001-2008 certificate, it insure our quality same as big factory. As everyone know china mold is much cheaper than USA or Europe but injection molding will be more expensive, because the resin price in China is 50% higher or double. But if you only produce 1,000-50,000 pcs. then China will have big advantage. Moreover we can make print, paint and assembly in house.it also save a lot!

3,Our Sales Manager have rich experience in engineering.

Most of company will arrange sales girls to contact customer, they are lack of mold knowledge ,just transfer e-mail and said some holiday words but will get good commission(3-5% total price, of course the cost will be calculated in their quotation).our Sales Manager will handle the job for both sales manager and project manager. It will make sure our professional service get through the whole process and the communication is more efficient.

CNMOULDING PRODUCES INJECTION MOLDING EQUIPMENT FOR VARIOUS USES

Almost every household material that is made out of plastic requires the process of injection molding. Only professionals can create such products and one should make a proper research before purchasing equipment for injection molding process. There are various websites selling plastic injection materials and one of them is CNMOULDING.

Before buying a product one can have a look at the experience of the company and the reviews of their previous customers. The present CNMOULDING industry involves both screw type machines and plunger type machines. The screw type injection molding is common among the customers and most of the clients are on the lookout for the screw type machines. The molding of plastic is different for different products depending on the type of plastic. Each product is different and one needs to be aware of his requirements before purchasing the product.

A company with good standards and certification can produce such products and one cannot expect to get quality injection molding machine from an amateur. CNMOULDING follows a very complicated process to make sure that the customers get quality equipment. The buyers can have a look at the quality control process of the company by visiting this link http://www.chinamoldmaker.org/equipment/mold-equipment/. Having a look at the injection molding process will helps the buyers in understanding the quotation process and the pricing structure of the company. This also helps in making a proper research on the experience of the company and one can be rest assured that they are with an experienced company.

The process followed by professioanls makes sure that the plastics can be re-used and recycled and this helps in reducing wastage. They have an eco-friendly process that helps in reducing wastage. There are huge amount of customers who like to use eco-friendly processes and go with the ones who follow a greener process that reduces wastage. CNMOULDING is one of those companies that focuses on reducing wastage and makes sure that these CNMOULDING processes are done in an environmentally friendly manner.

The products on the website also include automotive products, door closers, covers, iPhone cases and much more. People can have a look at all the products and compare them according to their needs. Once the buyers get the products that meet their requirements and budget they can make sales enquiry through the website. The process of injection molding makes production processes much easier and faster. It reduces errors during production processes and makes sure that it is done in a cost effective manner.

About CNMOULDING:

Website:http://www.cnmoulding.com

CNMOULDING is a company based in China that has been producing various injection molding equipment. They have been in this field for a long time now and sell products around the world. The buyers can have a look at the FAQ section and the industrial processes followed by the company on their website. One can make product enquiries through the above mentioned website.

Common types of plastics, advantages and disadvantages, the main defect (b)

PS material (polystyrene) (General Purpose Polystyrene GPPS, commonly known as: PS; high impact polystyrene HIPS, commonly known as: super glue is not broken) for the production of insulating transparent pieces, decorative pieces, and chemical equipment, optical instruments, etc. ʱ??

Forming characteristics: 1. amorphous material, moisture absorption is small, without fully dry, difficult to break down, but the thermal expansion coefficient, easy to produce internal stress, good mobility, can bolt or plunger-type injection molding machine.

2. to use high melt temperature, high mold temperature, low injection pressure, injection time extend help to reduce stress. Prevent shrinkage and deformation. Chemical and physical properties: Most commercial use of PS are transparent, non-crystalline material. PS has very good geometric stability, thermal stability, the optical transmission characteristic, electrical insulating properties and a very slight hygroscopic tendency. It is resistant to water, dilute mineral acids, but can be strong oxidizing acids such as concentrated sulfuric acid corrosion and can be expanded and deformed in some organic solvent. Typical shrinkage between 0.4 to 0.7%.

POM (POM, commonly known as: steel) heat-crystalline plastic, melting point of 165 to 175 degrees, the nature of the nearest metal.

Advantages: 1 has high mechanical strength and rigidity.

2. The highest fatigue strength.

3. High environmental resistance, resistance to organic solvents.

4. Resistance to repeated impact resistance.

5. wide temperature range (-40 to 120 degrees).

6. good electrical properties.

7. good recovery.

8. The self-lubricating properties, good wear resistance.

9. excellent dimensional stability.

Disadvantages: 1. process if prolonged high temperatures can lead to thermal decomposition.

2. No self-extinguishing.

3. antacid poor.

4. forming a large shrinkage.

Chemical and physical properties: POM is a tough elastic material, even at low temperatures are still very good creep properties, geometric stability and impact resistance. POM homopolymer materials have both copolymer material. Homopolymer material has a very good extension strength, fatigue strength, but not easy to process. Copolymers have good thermal stability, chemical stability and ease of processing. Both homopolymer material or copolymer materials are crystalline materials and are not easily absorb moisture. The high crystallinity of POM cause it has a fairly high shrinkage, can be high up to 2% to 3.5%. For a variety of enhanced materials have different shrinkage.

 PVC (polyvinyl chloride) Chemical and physical properties: Rigid PVC is one of the most widely used plastic materials. PVC material is a non-crystalline materials. PVC material in actual use, often by adding stabilizers, lubricants, auxiliary processing agent, pigment, impact agents and other additives. PVC material is not easily flammable, high strength, resistance to climate variability and excellent geometric stability. PVC of oxidants, reducing agents and strong acids have a very strong resistance. However, it can be concentrated oxidizing acids such as concentrated sulfuric acid, concentrated nitric acid corrosion and does not apply to contact with aromatic hydrocarbons, chlorinated hydrocarbons occasions. PVC melt temperature during processing is a very important process parameters, if this parameter incorrectly will cause the material to decompose problems. PVC is rather poor flow characteristics, the process is very narrow range. Especially high molecular weight PVC material more difficult to process (this material is usually added to lubricants to improve the flow characteristics), so commonly used are low molecular weight PVC material. PVC contraction rate is very low, typically 0.2 to 0.6%.

PE (polyethylene)

A. is the largest output, the most should be the plastic in the world, with its output accounting for 30% of world plastics production.

B. The structure of long chain-like structure or a branched structure, a crystalline polymer type song.

C. odorless and tasteless flammable white powder, the appearance of floating white.

D. excellent electrical insulation properties, high frequency cable insulation should be made.

E. having high chemical stability.

F. good low temperature properties, good air permeability, can make agricultural films, bags.

PP (polypropylene, commonly known as the pleated plastic) is the most common plastic produce a heat-resistant, high yield strength, high bending labor life. Shrinkage greater resistance to impact strength with temperature changes. Insufficient rigidity. Flammable Chemical properties of stability, good dielectric properties, better engage in chemical erosion resistance, the ability to soak 80 degrees below the inorganic acid, lye, salts, and many organic solvents, water absorption is also minimal. At the melting point has good mobility, good molding properties Chemical and physical properties:. PP is a semi-crystalline materials. To be more rigid than PE and has a higher melting point. Since the type of PP homopolymer temperature is higher than the above 0 ℃ very brittle, so many commercial PP material is added 1-4% ethylene random copolymer or a higher ratio of clamp-stage ethylene content copolymer. PP copolymer-based material has a lower heat distortion temperature (100 ℃), low transparency, low gloss, low rigidity, but have a stronger impact strength. PP ethylene content increases strength increases. PP Vicat softening temperature of 150 ℃. Due to the high degree of crystallinity, the surface rigidity and scratch resistance properties of this material is very good. PP environmental stress cracking problem does not exist. Generally, the use of glass fiber, metal additives or thermoplastic rubber modified PP. MFR PP turnover ranges from 1 to 40. Low MFR PP material better impact properties but extend lower strength. MFR for the same material, copolymer-based homopolymer type intensity ratio is higher. Since the crystal, PP contraction rate is very high, typically 1.8 to 2.5%. And shrinkage direction uniformity than PE-HD material is much better. 30% of glass additive can shrink rate fell to 0.7%. Homopolymer and copolymer PP material has excellent resistance to moisture absorption, resistance to acid corrosion, anti-solubility. However, it aromatic hydrocarbons (such as benzene) solvents, chlorinated hydrocarbons (carbon tetrachloride) solvents is not resistance. PP did not like PE still has oxidation resistance at elevated temperatures.

PPE ethylene polypropylene chemical and physical properties: In general, PPE or PPO, commercially available materials generally mixed with other thermoplastic materials such as PS, PA and so on. These hybrid materials are generally still call it PPE or PPO. PPE or PPO hybrid has better processing characteristics than the pure material. Change characteristics depending on the mixture as a ratio of PPO and PS. Mixed with PA 66 of the mixed material has a stronger chemical stability at high temperatures. Moisture absorption of this material is very small, its products have excellent geometric stability. PS material mixed with non-crystalline, and mixed with the PA of the material is crystalline. Glass fiber additives can make the shrinkage rate decreased to 0.2%. This material also has excellent electrical insulating properties and low coefficient of thermal expansion. The viscosity depends on the mixture ratio of the material, PPO rate increase will result in increased viscosity.

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Common types of plastics, advantages and disadvantages, the main flaw

Plastic is a resin as a main component, at a certain temperature and pressure molded into a certain shape, and at room temperature can be maintained given the shape of the high molecular weight organic material. Plastic light weight, high strength. Usually density 0.9-2.3g / mm³ is 1 / 8-1 / 4, 1/2 of aluminum, iron and steel excellent electrical insulation properties, good chemical stability, anti-friction wear resistance, light transmittance and protective properties Good, good damping silencer performance. After heating the surface of the plastic according to the performance into thermosetting plastics and thermoplastics. Occur at a certain temperature over a period of time of heat, pressure or added hardener chemical reaction and hardened, hardened plastic chemical structure changes, hard, insoluble in solvents, no longer softened after heating, such as temperature: thermosetting plastic Features too high to decompose. Such as Bakelite (commonly known as bakelite), epoxy plastic (EP) and the like. Thermoplastic Features: biological state change hair after being heated to soften or melt into a sticky fluid state from a solid, but can harden after cooling from solid, and the process can be repeated many times. The molecular structure of the plastic itself is not changed. Plastics such as polyethylene (PE), polyvinyl chloride (PVC).

PC material (polycarbonate)

Advantages: 1 has high strength and elastic modulus, high impact strength, wide temperature range.

2. High transparency and freedom of dyeing

3. good fatigue resistance

The excellent electrical characteristics

5. low mold shrinkage, good dimensional stability.

Disadvantages: 1. hydrolysis resistance

2. chemical resistance, notch effect

3. The problem is easy to produce finished poorly designed internal stress.

Chemical and physical properties: PC is a non-crystalline engineering materials, with a particularly good impact strength, heat stability, gloss, inhibit bacterial properties, flame retardant properties and fouling resistance. PC de gap estimated impact strength in Iraq (otched Izod impact stregth) is very high and very low shrinkage rate, usually 0.1% to 0.2%. PC has good mechanical properties, but poor flow characteristics, so the injection molding process more difficult this material. PC quality in the selection of the material, we should expect the final product as a benchmark. If the plastic parts require high impact resistance, then use a low turnover rate of PC material; the other hand, you can use the high turnover rate of PC material, which can optimize the injection molding process.

Material ABS (acrylonitrile - butadiene - styrene copolymer, commonly known as: super glue is not broken)

Advantages: 1. hard, easy extrusion

2. Flame

3. easy to dye

4. Impact

5. The surface resistance

Disadvantages: 1. poor solvent resistance

2. Low Dielectric strength

3. Low stretch rate

Forming characteristics: 1. amorphous material, liquid medium, moisture large, must be fully dry, glossy plastic surface should take time to preheat the drying 80-90 degrees, 3 hours

2. should take high melt temperature high mold temperature, high precision mold, mold temperature should take 50-60 degrees, high-gloss heat-resistant plastic parts, mold temperature should take 60-80 degrees.

Chemical and physical properties: ABS is, butadiene and styrene of three monomers synthesized from acrylonitrile. Each of the monomers having different characteristics: acrylonitrile high strength, thermal stability and chemical stability; butadiene have toughness and impact resistance properties; styrene easy processing, high-quality finish and high strength. Morphologically, ABS is an amorphous material. Polymerization of three monomers produces a terpolymer having two phases, a styrene - acrylonitrile continuous phase, and the other is a polybutadiene rubber dispersed phase. The properties of ABS depends on the ratio of the monomers and the molecular structure of the two phases. This allows great flexibility in product design, and the resulting market hundreds of different quality ABS material. These different quality materials offer different characteristics, such as moderate to high impact resistance, from low to high finish and high heat distortion characteristics. ABS material with superior ease of processing, appearance, low creep and excellent dimensional stability and high impact strength.

more information www.plastic-injectionmoulding.com 

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Characteristics of transparent plastic material commonly used in the injection molding process and (b)

(IV) injection molding process should pay attention to the issues (including the requirements of the injection molding machine)

In order to reduce internal stress and surface quality defects in the injection molding process should pay attention to the following aspects of the problem.

a) should be used as the special screw with a separate temperature control nozzle of the injection molding machine;

b) injection temperature plastic resin does not decompose under the premise, to use the high humidity injection;

c) Injection pressure: generally higher in order to overcome the melt viscosity of the defect, but the pressure is too high will produce stripping difficulties caused by internal stress and deformation;

d) Injection speed: In the case of filling meet, generally should be low, it is best to use a slow-fast and slow multi-stage injection;

e) dwell time and molding cycle: to meet product filling, no depression, the case of the bubble; should be kept short to minimize melt residence time in the barrel;

f) screw speed and back pressure: Under the premise of quality to meet the plastics should be as low as possible to prevent degradation of the possible;

g) Mold temperature: cooling products good or bad, a great impact on the quality, so the mold temperature must be able to precisely control the process, if possible, some good mold temperature should be high.

Issue (5) other aspects of

Because you want to preventing the deterioration of the surface quality, minimize the use of general injection molding release agent; when the use of regrind shall not exceed 20%. Except for the outside pet, after the products should be treated to eliminate stress, pmma should at 70-80t hot air circulation drying 4 hours; pc should be in clean air, glycerol. Liquid paraffin and other heating 110-135 ℃, time according to the product, the highest need more than 10 hours. The pet must biaxial stretching step, in order to obtain good mechanical properties.

Third, transparent plastic injection molding process

(A) process characteristic transparent plastic: In addition to these common problems, also have some processes transparent plastic properties, are summarized as follows:

1, process characteristics pmma the pm-ma viscosity, somewhat less liquidity, and therefore must be high temperature materials, high injection pressure injection job, which affect the injection temperature is greater than the injection pressure, but the injection pressure is increased, it will help to improve shrink products rate. Injection wide temperature range, the melting temperature of 160 ℃, decomposition temperature of 270 ℃, material temperature and therefore wide adjustment range, the process better. Therefore, to improve mobility, we can proceed from the injection temperature. Poor impact resistance, good abrasion resistance, easy to draw flowers, easy to rattle, it should raise the mold temperature, improve the condensation process, to overcome these deficiencies.

2, the technical characteristics of pc pc viscosity, high melting temperature materials, poor mobility, must therefore be at a higher temperature injection (between 270-320 ℃), the material temperature adjustment range is relatively narrow, technology is not as good as pmma. Injection pressure has little effect on liquidity, but the viscosity, still larger injection pressure, corresponding to prevent stress, dwell time should be as short as possible. Shrinkage, dimensional stability, but a large internal stress, easy to crack, it is appropriate to raise the temperature rather than pressure to improve fluidity, and improving the mold temperature, mold structure and to improve the post-processing to reduce the possibility of cracking. When the low injection speed, the gate prone to defects such as corrugations, radiation nozzle temperature to be controlled separately, mold temperature is higher, the flow channel, gate resistance is smaller.

3, the technical characteristics of pet pet molding temperature is high, and the material temperature adjustment range is narrow (260-300 ℃), but after melting, good liquidity, so the process is poor, and often at a nozzle extension to be added to the anti-flow devices. Mechanical strength and performance after the injection is not high, we must in order to improve performance and modified by stretching step. Precise mold temperature control, to prevent warping, distortion of the important elements back to back this proposal hot runner mold. Official high mold temperature, otherwise it will cause poor surface gloss and stripping difficulties.

Fourth, transparent plastic parts defects and solutions

 (A) silver streaks: from filling and condensation process, the internal stress anisotropy effects of stress generated by the vertical direction, so that the resin flow occurs on orientation, while non-current orientation and produce different refractive index and raw silk flash pattern, when After its expansion, may make the product cracks. In addition to the injection molding process and mold note, the best products for annealing. As pc material can be heated to above 160 ℃ holding 3-5 minutes, then natural cooling can be.

(B) bubble: Master in moisture and other gases within the resin did not break out, (in the mold condensation process) or because of insufficient filling, excessive condensation condensing surface and form a "vacuum bubble."

(C) the surface gloss difference: mold roughness, on the other hand the condensation too early, so that the resin can not copy the state of the mold surface, all of which make the surface uneven produce small concave strike, leaving the products lose their luster.

(d) shock pattern: refers to intensive ripple from the center sprue formed, the reason because the melt viscosity is too large, front-end material has been condensed in the cavity, then break through this material and condensing surface, leaving the surface shock pattern ʱ??

(E) white, fog halo: mainly due to the fall in the dust in the air into raw material or feedstock caused by too much moisture.

(f) white smoke, black spots: mainly due to the plastic barrel, due to local overheating of the machine and produce resin cylinder formed by the decomposition or deterioration.

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Characteristics of plastic commonly used in transparent materials and injection molding process (a)

Because plastic is light weight, good toughness, molding and easy. Low cost, and therefore in the modern industrial and household products, more and more plastic instead of glass, especially for optical instruments and packaging industry, develop rapidly. However, due to its transparency requirements better, higher abrasion resistance, impact toughness is better, so the plastic components, injection of the process technology, equipment, molds, they have made a lot of work to ensure that they be used instead of glass plastic (hereinafter referred to as transparent plastic), good surface quality, so as to achieve the requirements of use.

Currently on the market transparent plastic commonly used are poly (methyl methacrylate) (commonly known as acrylic or Plexiglas, codenamed pmma), polycarbonate (code pc). Polyethylene terephthalate resin (codenamed pet), transparent nylon. as (acrylonitrile-styrene copolymer), polysulfone (codenamed psf), of which we have the most contact is pmma, pc and pet three plastic, because of space limitations, the following three plastic as an example to discuss Characteristics of transparent plastic and injection molding process. A transparent plastic properties of transparent plastics must first have a high transparency, and secondly to have a certain strength and wear resistance can impact resistance, heat resistance and better, excellent chemical resistance to water absorption should be small, the only way to use , and can meet the requirements of transparency and long-term deformation

Second, transparent plastic injection molding process should pay attention to common problems

Transparent plastic due to high light transmittance, a necessary requirement the plastic surface strict quality requirements, can not have any markings, pores, whitening. Halo fog, black spots, discoloration, poor gloss and other defects, and thus the entire injection molding process for raw materials and equipment. Mold, and even product design, we must pay great attention to and propose strict and even special requirements. Second, because the transparent plastic, mostly high melting point, poor mobility, so as to ensure the surface quality of the products, often in machine high temperature, injection pressure, injection speed and other parameters for fine adjustments to make when both full of plastic injection molding, without It will produce internal stress caused by deformation and cracking products.

Here its preparation of raw materials. Requirements for equipment and tooling, raw material injection molding process and product handling aspects, to talk about the matter should be noted.

Preparation and drying (a) the raw material at any point because it contains impurities in plastics, are likely to affect the transparency of the product, so the storage, transportation, feeding process, we must pay attention to the seal, to ensure a clean raw material. Especially raw materials containing water, can cause deterioration of raw materials is heated, so be sure to dry, and at the time of injection, the feeding must use the drying hopper. Also note that the drying process, the air inlet should preferably be filtered, dehumidified to ensure that does not contaminate raw materials.

(Ii) Clean barrel, screw and its annexes to prevent contamination of raw materials and there are old material or impurities in the screw and accessories depression, especially poor thermal stability of resin exist, so before use, screw cleaning agents are applied after the shutdown clean all parts, so that it can not stick with impurities, when there is no screw cleaning agent, available pe, ps and other resin cleaning screw. When the temporary shutdown, in order to prevent material at high temperatures to stay a long time, causing degradation should be drier and barrel temperature decreases, such as pc, pmma, etc. barrel temperature should be reduced to below 160 ℃. (Hopper temperature for pc should be reduced to below 100 ℃)

(C) the issue in the mold design should pay attention (including product design) in order to prevent back flow of poor or uneven cooling caused by bad plastic molding, surface defects and deterioration in general in the mold design should note the following points. a) wall thickness should be uniform, stripping slope be large enough;

b) should be gradually transition. Smooth transition to prevent any sharp corners. Produce sharp edges, especially pc product must not have a gap;

c) gate and runner as large, chunky, and the location of the gate should be set according to the contraction condensation process, if necessary add cold material well;

d) the mold surface should be smooth, roughness low (preferably less than 0.8);

e) vent grooves must be sufficient, and when the exhaust gas in the air and melt;

f) In addition to pet, the wall thickness of not too thin, usually not less than 1mm.

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