Plastic Injection Molding In China

Plastic Injection Molding In China

Plastic injection molding in China is at a high level of expertise in comparison with other Asian countries. Taiwan also has much better working conditions, environmental regulations and worker relations than most it’s neighbors.
Government policies that have enabled the plastics industry to develop in a free-market manner. This has enabled the plastic injection molding industry to develop to a high technical level. The open market nature has given fair competition the ability to bring in high end jobs and industries.

What are some advantages of China injection molding manufacturers?

  • Decades of industrial growth and stability without destroying the environment
  • Safe and healthy working conditions for the employees. Taiwan has a long history or good human rights relations which reflects in it’s labor laws.
  • For the environment. Industry has cooperated with the government to keep the island clean and relatively unpolluted
  • Costs are generally one-third less than those of the USA. This means you can receive high quality at reduced prices.
  • Thermoplastic injection molds, thermosetting molds, and custom molds of all types have developed to a high level of expertise.
  • No history of human rights abuse

What are some industries China specializes in?

China has an excellent relationship with the US, Europe and Japan because of it’s political and economic system. This has enabled the island country to attract leading aerospace, automotive, electronics, computer, and small appliance companies.
How can you find a reliable plastic injection molding company in China? A good place to begin your search is here One of the top companies in Taiwan for thermoset molding is Longzu Plastic Molding Company They have been in business for over 40 years, which is a lifetime in plastics.

Plastic Injection Mold Making And Laser Machining

Plastic Injection Mold Making And Laser Machining

The use of laser machining for making plastic injection mould has been available for years, but has only received limited acceptance. This is partly due to the uncertainty of the new technology and the cost of the machines.

However, for the right application, laser machining is a very viable option. With the latest generation of precision laser cutting machines, there are many improvements. Cutting speeds have increased, accuracy has improved, surface finishes are better, and the cost has come down.

How can laser machining help a plastic mold maker?

Precision laser cutting is an ideal operation for engraving and the machining of very intricate, small, shallow cavities. One of the benefits of laser machining is that it can engrave on complicated contours very consistently and with a high degree of accuracy. It is also possible to use laser machining services to engrave molds with changing vertical wall angles.

Laser micro machining can produce small, intricate and precise cores and cavities as well. Because the geometry is produced directly from the CAD file, the laser machining operation can faithfully reproduce the designed shape.

Are lasers accurate?

A precision laser cutting machine can cut within microns. The newer machines are also 5 axis and able to machine a wide range of angles and shapes. The XYZ positioning accuracy can easily rival that of a high quality CNC machining center.

Are laser engraving machines safe?

While it might sound dangerous, a precision laser cutting machine is actually quite safe. Of course, somebody might be tempted to ignore common sense and stare at the laser beam with their naked eye, but even this is not so easily done. Generally, however, the machine just hums away, doing its required task.

Are lasers fast enough to compete?

Depending on the application, a laser machining tool is financially justifiable. The applications are limited to shallow details, which eliminates many projects. However, if your need is for intricate, shallow details, precision laser machining could be the answer.

Because the entire process is computerized and automatic, it readily lends itself to small scale production. The engraving of logos is a great example. If your logo is to be cut into a contoured surface, it may not be possible to CNC machine it, or even EDM it. This is where laser machining can be a viable option.

Applications for laser machining

Small hole machining and shaped hole machining are good applications for laser machining. Turbine cooling holes are often laser machined. The helical shape of the blades are no problem for the laser because there is no tool holder to interfere. It is just a beam of light and the head is able to move about much easier than a milling machine, for example. go out other page to know more about plastic mold

EDM Supplies

EDM Supplies For WEDM And Sinker Electrical Discharge Machines

EDM supplies are often overlooked in the rush to get things done in a precision machine shop, tool-and-die shop or Plastic injection mold making shop. This wastes both time and money, yet the solution is quite simple.

Without the best EDM supplies, quality and production both suffer. Also, the workforce morale takes a beating because even the simplest of tasks becomes very time-consuming without the proper equipment and EDM tooling.

Typical WEDM supplies

  • Precision brass hole drilling tubes (hole popper tubes)
  • Filter cartridges
  • Resin-virgin and regenerated
  • WEDM tooling such as System 3R, Hirschmann, Erowa and Hermann Schmidt
  • EDM wires
  • Replacement parts
  • Rust inhibitors
  • Chillers
  • Metal polish
  • Cleaners
  • Magnets

 Typical Sinker EDM supplies

  • Graphite, copper and copper tungsten electrode material
  • EDM tooling such as System 3R, Hirschmann, Erowa and Hermann Schmidt
  • Tapping electrodes
  • Dielectric fluids
  • EDM filters
  • Chillers
  • Rotating spindles
  • Tubing chucks
  • Magnetic chucks
  • Pallets
  • Surface finish gauges
  • Inspection equipment
  • Microscopes

Take the time to find the best solution for each aspect of EDM

One shop owner I know invested heavily in a CNC sinker EDM, yet neglected to buy any additional tooling. He failed to see the wisdom in upgrading his accessories and thus rendered his new EDM to the status of a fancy manual machine.

Rather than add accessories piecemeal, include the necessary tooling in the initial package, or at least make a coherent plan to build up the tooling over time.

A very short history of EDM tooling

For the general public EDM is still a relatively unknown metalworking process. Unless one has personal experience or knows someone who works in this field, chances are quite good that the world of electrical discharge machining is a mystery.

Like any specialized industry, EDM has it’s own terminology and way of doing things. The slang that is used could easily mislead a bystander into thinking something quite different is going on than is actually the case.

Words like tweak, bump, tickle, feather, smack, toast, NFG, fudge, hide and zit are all used on a daily basis. Actually, zit is less common now than in the past, due to improved circuitry and techniques. A zit is a DC arc, or pit that is EDM’d into the steel by mistake.

With the ever-improving technologies available today, EDM has moved away from being somewhat of a black art and into a fully explainable and manageable metalworking process. No longer is it a machine of last resort or specialty, but a mainstay of the industry.

Robots, electrode changers and pallets for sinker EDM

At one time, not so long ago, electrodes were set up manually, requiring continual operator attention. There were no standardized holders and most people used angle blocks, vises or Vee-blocks to set up and hold electrodes. This actually worked quite well, but is very time-consuming and demands a high level of skill.

Next came the standardized electrode holders, such as System 3R. This changed everything almost overnight. Now electrodes could be moved from the milling machine, lathe or grinder and installed in the sinker EDM with no set up time.

Improvements were made on the holders and the repeatability and reliability increased dramatically. Pneumatic chucks made the process simpler and more accurate.

Tool changers were built into the sinker EDM to enable overnight machining and less operator involvement.

Now there are robots that select workpieces mounted on pallets and change electrodes, leaving the guesswork entirely out of the equation. These sophisticated tools require a high degree of organization, but once set up they can run almost indefinitely. Some tool magazines can hold 100’s of electrodes and many pallets with mounted workpieces.

Add pre-setting stations and inspection stations to the process and you truly have a complete manufacturing cell for the EDM department.

More articles on EDM manufacuturing of plastic molds please go to this website site.

Aluminum Casting China

Aluminum Casting China

Welcome to the Aluminum Die Casting resource . Here you’ll find over 540 of the webs top sites regarding aluminum casting China companies. By navigating through our alphabetical links you’ll discover numerous, helpful links pointing to sites solely related to aluminum casting worldwide. We’ve taken the time to research these sites so you don’t have to. All the resource links on this site are handpicked and are ranked as the most helpful informational sources online. After all, we know how time consuming it can be searching for a topic such as casting aluminum.

ASTM A 116 (1995) Zinc- Die Coated (Galvanized) Steel Woven Wire Fence Fabric
ASTM A 121 (1999) Zinc-Coated (Galvanized) Steel Barbed Wire
ASTM A 153/A 153M (1998) Zinc-Coated (Hot Dip) on Iron and Steel Hardware
ASTM A 491 (1996) Aluminum-Coated Steel Chain-Link Fence Fabric
ASTM A 585 (1997) Aluminum-Coated Steel Barbed Wire Die.
ASTM A 666 (1999) Annealed or Cold-Worked Austenitic Stainless Steel Casting Sheet, Strip, Paste, and Flat Bar
ASTM A 824 (1995) Metallic-Coated Steel Marcelled Tension Wire for Use With Chain Link Fence
ASTM C 94/C 94M (2000) Ready-Mixed Concrete
ASTM D 4541 (1995el) Pull-Off Strength of Coatings Using Portable Adhesion Testers
SECTION 02821 Page 1

Cut-off concentration (mg/L
Total Recoverable Aluminum ……. 0.75
Total Recoverable Copper ……….. 0.0636
Total Recoverable Iron …………….. 1.0
Total Recoverable Lead …………… 0.0816
Total Recoverable Zinc ……………. 0.065
Several congeners of PCBs (PCB-1016, -1221, -1242, -1248, -1260) were above established benchmarks, however, EPA believes that these constituents will readily bound up with sediment and particulate matter. Therefore, EPA believes that BMP’s will effectively address sources of PCBs and that monitoring for TSS will serve as an adequate indicator of the control of PCBs. Aluminum RCC.

(1) Monitoring Periods. Scrap and waste material processing and recycling facilities shall monitor samples collected during the casting periods of: January to March, April to June, July to September, and October to December for the years specified in paragraph a. (above).

(2) Sample Type. Aluminum minimum of one grab sample shall be taken. All such samples shall be collected from the discharge resulting from a storm event that is greater than 0.1 inches in magnitude and that occurs at least 72 hours from the previously measurable (greater than 0.1 inch rainfall) storm event. The required 72-hour Die Casting event interval is waived where the preceding measurable storm event did not result in a measurable discharge from the facility. The required 72-hour metal casting interval may also be heated where the molten metal that less than a 72- hour interval is representative for local die plan events during the season when sampling is being conducted. The grab sample shall be taken during the first 30 minutes of the discharge. If the aluminum collection of a grab sample during the first 30 minutes is impracticable, a grab sample can be taken during the first hour of the discharge, and the discharger shall submit with the monitoring report a description of why a grab sample during the first 30 minutes was impracticable. If storm water discharges associated with industrial activity commingle with process or non-process water, then where practicable, heat Aluminum die casting must attempt to sample the density or discharge before it mixes with the non-ferrous elements.

Please browse our Aluminium Die Casting directory via our alphabetical links now. Rest assured, you’re only one click away from finding the die casting. Resources and information you’ve been searching for.

How to make plastic injection mold

How to make plastic injection mold

The process of making a plastic injection mould consist of determining what should be the size of
the mold, designing the mold, ordering required materials for the design, creating a rough shape, heating the mold, precision machining, wire cutting, polishing and fitting and trial of the mold.

Step 1: Determining the size of the plastic injection mold.

This process is not hard and does not require a lot of time. The end product, the plastic shape, determines the size of the mold.

Step2: Designing the mold.

Computer CAD design is used to draw the design. First set a 2 dimension layout and make sure you have all the mold
design features marked such as the size of the mold, parting line, the layout of the cavities are all set. Note the information that will be needed such as the mechanical design and the accessories that will be used.

After the two dimension layout made is satisfying and all information is noted make a
detailed 3D design. This will require programming skills to create. It may take some time to complete the designing with regards to the complexity of the mold.After the first 3D design is made it is necessary to assess any need for adjustments and the flow of the mold.

Step 3: Ordering the required molding material

After your design drawing is completed its time to order the required material. This may include desire steel, cutting tools and plastic part samples.

Step 4: Creating a rough shape of the plastic molds

Sizing of the steel then milling and drilling comprises this step. Make the desired steel shape and drill the holes needed as per the design in a rough work machine. Leave polishing and smoothing for later.

Step 5: Heating the mold

Heating is done as a form of treatment after creating the rough shape to harden and balance the created steel shape. Not every type of steel may need heating, an example, the P20.

Step 6: Precision machining.

Precision machining works slower due to the hardened steel properties but will get the design dimension created as per the design drawing.

Step 7: Wire cutting and EDM

Wire cutting is a process where special holes are made in to the design. These holes include pin holes for the ejector, for the lifters and the inserters. EDM helps work on narrow spaces which cannot be machined easily or where the space is too small for the cutting tool to get in.

Step 8: Polishing and fitting
polishing and fitting the created mold in to the mold maker machine follows.
The mold maker machine will collect all parts put into it and will follow the
design drawing to make the finished plastic mold. When the machine work is done further
polishing and engraving follows to complete the design.

Step 9: Trying the mold.

After the mold is created it will be good to try if it will work for the desired plastic shapes. The mode is installed in the plastic injection molding machine and injection parameters are set to work on the plastic samples acquired. If the mold is good enough for the job, well and good, the mold creation process is complete. You can now proceed to create the desired plastic products or sell the design to another company.

Aluminum Die Castng

Aluminum Die Castng

(1) malleable cast iron is a certain range of chemical composition of white cast iron by annealing the resulting solid graphite graphite cast iron floc group. It has a very high plasticity, it is “malleable” Aluminium Die Casting name, in fact, is not forged, but it can be a good bend, elongation up to 15% strength is also high.

(2) Pressure casting is liquid or semi-liquid metal, filled with high-speed die casting mold cavity, and rapid solidification under pressure molding, casting and get a special casting method is generally applicable to non-ferrous metals. These two processes die casting from the use of the material, size and shape of the product, process methods, products, applications are different

Die casting technology and production

The book was discussed in detail the basic knowledge and production of the die casting technology. The main contents include casting, die casting machine principle, parameters of die casting process and its determining method, die casting pouring system and die casting die structure design, quality control, production of the die casting Aluminum Die Casting and die casting workshop operation management. Also introduced CAD for die casting die and die casting filling process simulation technology and application etc.. This book both basic theory and practical technology of die casting die for die casting industry, the technical staff, production staff and management personnel to read or as training materials, but also can be used as the relevant professional colleges teaching reference books.

Book order



The first chapter of die casting process and die casting overview

1.1 die casting process overview

1.1.1 die-casting process principle

1.1.2 die-casting production department and production process

1.1.3 die-casting process characteristics

1.2 die casting overview

1.2.1 die casting of the classification and technical requirements

1.2.2 die casting process

1.3 die casting technology development

The second chapter die casting machine and its properties and selection

2.1 classification of die casting machines

2.2 die-casting machine ‘s basic mechanism and function

2.3 cold chamber die casting machine and hot chamber die casting machine process characteristics

2.3.1 cold chamber die casting machine process characteristics

2.3.2 hot chamber die casting machine process characteristics

2.4 die casting machine main technical parameters and significance

2.5 the choice of die-casting machine

The 2.5.1 die casting machine type selection

The 2.5.2 die casting machine class selection

2.5.3 die casting machine tonnage determine

2.5.4 die casting machine technical parameter calculation

The 2.5.5 die casting machine energy calculation

2.6 modern advanced function of die casting machine

2.6.1 high speed, efficient and flexible injection system

2.6.2 advanced real-time control system

2.6.3 fault monitoring, remote diagnosis and alarm function

2.6.4 data collection, analysis and processing, production management and statistical analysis

2.6.5 die-casting workshop for network monitoring, communication management and production of automatic scheduling

2.6.6 partial pressure

The 2.6.7 hydraulic system

2.6.8 automatic die casting machine

The third chapter the injection process and die casting process parameters

A 3.1 injection process and injection process curve

3.1.1 injection process

3.1.2 injection process curve

3.1.3 injection process settings

3.2 parameters of die casting process and its determining method

3.2.1 pressure

3.2.2 speed

3.2.3 time

3.2.4 temperature

Chapter fourth design of gating system

4.1 gating system composition, types and design key points

4.1.1 gating system.

4.1.2 gating systems

4.1.3 gating system design content and knowledge requirements

4.1.4 gating system design

The 4.2 gate design

4.2.1 ingate position determination

4.2.2 ingate area calculation

4.2.3 gate thickness, width and length determination

4.2.4 gate and cavity is connected by way of

4.2.5 gate design data

4.2.6 different gating system filling simulation example

4.3 runner design

The basic form of 4.3.1 runner

4.3.2 runner structure

4.3.3 sprue design

4.3.4 fan sprue design

4.3.5 taper runner design

The 4.4 exhaust system

The role of 4.4.1 exhaust system

4.4.2 exhaust system for determining the position of and the main points of the design

4.4.3 exhaust system structure and size

4.5 P-Q2 principle and its application

4.5.1 technology thought and purpose

Based on 4.5.2 theory

4.5.3 die-casting mold flow pressure curve (die casting pressure demand curve)

4.5.4 machine effective pressure line

4.5.5 P-Q2 diagram

Chapter fifth design of die casting die

5.1 die casting mold basic structure and function

5.2 die casting mold design

5.2.1 design basis and steps

5.2.2 design points

5.2.3 design steps and contents

The 5.3 type of identification

5.3.1 parting surface form

5.3.2 choice of parting surface

5.3.3 typing scheme example

5.4 cavity arrangement

The 5.5 mold body structure and parts design

Basic structure of the 5.5.1

5.5.2 insert fixed forms and sizes

The 5.5.3 template size determination

5.5.4 die casting and pressure chamber and plunger and template matching size

5.5.5 guide pillar and the guide sleeve design

5.5.6 molding size determination

5.6 the design of the core-pulling mechanism

5.6.1 core-pulling mechanism classification and composition

5.6.2 core-pulling mechanism working principle and main parameters

The 5.7 push-out mechanism design

5.7.1 ejecting mechanism and drive means.

5.7.2 ejecting mechanism design

Commonly used 5.7.3 top rod form

5.7.4 commonly used by pushing the tube and the push plate form

5.8 die casting technical requirements

5.8.1 die match between the parts fit tolerance

5.8.2 die casting different parts work surface roughness

5.8.3 die-casting mold assembly diagram should be marked on the technical information

5.8.4 die-casting mold shape and installation size

5.8.5 die-casting mold assembly technical requirements

5.9 die materials and heat treatment

5.9.1 die-casting mould forming parts material requirements

5.9.2 die-casting mold material of main parts and heat treatment

5.9.3 abroad and home, die-casting die used steel table

The sixth chapter die-casting mold computer aided design and die casting process simulation

6.1 CAD for die casting die

6.1.1 general CAD software

6.1.2 die-casting die for CAD software

6.1.3 die and process content and application of CAD software

6.2 die casting process simulation

Basic knowledge of 6.2.1 simulation technology

The basic structure and function of the 6.2.2 simulation software

6.2.3 simulation software

6.2.4 simulation software selection

6.2.5 on the simulation software of user requirements

6.3 die casting process simulation example

6.3.1 plunger variable motion simulation

6.3.2 filling mode and oxidation and air entrainment defect

6.3.3 cold septal defect formation

6.3.4 filling speed and the filling state

6.3.5 gating system of flow simulation

6.3.6 gating system design scheme optimization

Other 6.3.7 simulation

6.4 die casting technology on the simulation software requirements

The seventh chapter of die casting alloy and its smelting technology

Composition and characteristics of 7.1 aluminum alloy

7.1.1 casting aluminum alloy

7.1.2 die casting zinc alloy

7.1.3 die casting magnesium alloy

7.1.4 die casting alloy casting process performance comparison

7.2 alloy smelting and melting equipment

7.2.1 alloy melting

7.2.2 aluminum and zinc alloy smelting furnace

7.2.3 magnesium alloy smelting equipment

7.3 aluminum alloy melting point

7.3.1 smelting equipment and tools ready

7.3.2 charge

7.3.3 charging

7.3.4 smelting

7.3.5 degassing and slag removal

7.3.6 melt conveying

7.4 zinc alloy melting point

7.4.1 smelting equipment and tool protection

7.4.2 charge

7.4.3 charging

7.4.4 alloy smelting

7.4.5 waste disposal

7.5 mg alloy melting point

7.5.1 crucible and melting instrument

7.5.2 charge

7.5.3 charging

7.5.4 magnesium alloy ingot preheating

7.5.5 protection gas using

7.5.6 smelting operation

7.5.7 waste material recycling and refining

7.5.8 magnesium alloy smelting operation safety

The eighth chapter die-casting workshop and die casting operation

8.1 die casting workshop

8.1.1 die-casting workshop planning and layout

8.1.2 die-casting workshop organization and management

8.1.3 die-casting workshop environment

8.2 die casting operation

8.2.1 casting operations personnel arrangement

8.2.2 site and equipment ready

8.3 die casting operation

8.3.1 die-casting mold check

8.3.2 die casting installation

8.3.3 cooling water connection

8.3.4 die-casting mold temperature control

8.4 die casting production

8.4.1 die and mold repair

8.4.2 plunger and the pressure chamber installation and maintenance

8.4.3 pressure chamber filled with a degree and thickness of residual material control

8.4.4 die releasing agent and lubricant selection

8.4.5 die casting mold cleaning

8.4.6 casting and injection

8.4.7 die out

8.4.8 die casting mold maintenance and custody

8.4.9 casting work instruction documents

8.4.10 casting operation matters needing attention

8.5 die casting cleaning

8.6 die casting processing

8.6.1 die casting of orthopaedic

8.6.2 die casting aging treatment

8.6.3 die casting mechanical processing

8.6.4 die casting infiltration process

8.6.5 die casting surface treatment

The ninth chapter die casting defects and quality control

9.1 die casting defects and elimination measures

9.1.1 surface defects and eliminating measures

9.1.2 internal defects and elimination measures

9.1.3 shape and size of defects and elimination measures

The 9.1.4 matrix incoherent defects and elimination measures

9.1.5 other defects and elimination measures

9.2 die casting defects elimination strategy

9.3 die casting quality detection method

9.3.1 visual inspection method

9.3.2 metallographic examination

9.3.3 mechanics performance test

9.3.4 chemical composition test

9.3.5 nondestructive inspection

9.3.6 withstand voltage test

9.3.7 corrosion test

9.3.8 dimension inspection method

9.4 die casting acceptance

9.5 die casting quality control

Influence of casting quality factor 9.5.1

9.5.2 quality control work

The 9.5.3 inspection system

9.5.4 quality control point die casting setting and testing factors

9.5.5 quality control procedures

The 9.5.6 quality management system

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Injection Molding Process

Injection Molding Process

The thought of processing PEEK (polyetheretherketone) or other high-temp resins can send nervous tremors through many a molder’s body.  I know, as a molder who learned the craft on a steady diet of PP and PE closures with their low melt temperatures and cold a plastic molds, my first PEEK experience made me edgy to say the least.  But I’ve since come to realize that PEEK is just another thermoplastic resin and, like the others, can be molded safely and efficiently with just a few precautions.

PEEK is widely believed to be one of the highest performing thermoplastics on the market and its end properties more than justify any trials and tribulations you may encounter processing it. PEEK is a linear aromatic, semi-crystalline thermoplastic having excellent wear, chemical and hydrolysis resistance. It has very low flame/smoke toxicity and excellent electrical properties that preclude the need for additives in many cases.

PEEK processes at a high melt temperature nearing 720°F, and both the press barrel and controls must be capable of this. On many plastic molding machines the high heat software is an option and I recommend ceramic high-temp heat bands whenever possible. A special screw and barrel are generally not needed, but consider hard units if running filled PEEK resins. We typically use sliding ring non-return valves, GP or Eliminator™ tips and don’t recommend ball checks or shutoff nozzles.

A hot mold is the key to achieving crystallinity in PEEK parts. Purging PEEK allows you to see the color change from a translucent to a solid colored crystalline state. If the mold is too “cold” (i.e. not hot enough) the parts will have that discoloration or partial translucency, and the quality of the end product will be compromised. The mold, in most cases, must be between 350°F and 450°F. This is steel temperature and requires oil or cartridge heat to maintain this level. Complex parts may require better temperature control so oil would be the preferred option. We also recommend the use of thermocouples to verify and monitor the steel temperature.Plastic Mould & Plastic Molds

These plastic molds must be specifically designed to run high-temp materials with draft, finish, undercuts and steel types all factored in from the beginning. Insulator plates between press platen and mold clamp plates are a must. The preferred steel type would depend on whether or not the resin uses any abrasive fillers but should have a minimum hardness of 52-54 Rc.

The resin also must be very dry to process well and achieve the desired end properties. This means that the resin must be at 0.02% moisture or below. We typically recommend drying the resin at 300°F for at least 3 hours. We also suggest the use of a moisture analyzer to assure dryness.

PEEK can be quite costly, but you should be able to use 30% dry first-pass regrind with unfilled PEEK and 10% with filled PEEK.

Safety should be a primary consideration when molding PEEK, both for purging and while working with the mold. Wear safety glasses and/or a face shield, Kevlar or Kevlar/stainless steel sleeves, and heavy cotton cloves when purging and reaching into the mold.

When preparing for your PEEK experience, research it well with your resin supplier. The above information is based on my experience, but it should used as a reference only. Also, make sure you don’t neglect recognized scientific principles when working with any thermoplastic material. With a bit of common molding sense, your PEEK experience can and should be a rewarding one. click here to get more detail about plastic molds and plastic molding technology.

Injection Molds

Injection Molds

The world has become very dependent upon plastic products. From household items to industry and aerospace, plastic in its many formulations has transformed modern manufacturing and created conveniences and economies unimagined in the early decades of the 20th century.

Injection Molds
The injection moulding industry took hold in 1946 when James Hendry built a screw injection molding machine. But, his technology was based on an earlier invention by John Wesley Hyatt who, in 1868 injected hot celluloid into a mold to make billiard balls. Hyatt’s method used a plunger to force the ma

terial inside a mold. Hendry’s improvement was revolutionary because it eliminated the plunger and replaced it with an auger-type action that better distributed material and facilitated the use of plastic inside molds.


Today’s plastic molds use much the same process and produce a wide variety of products from car panels to outdoor furniture, small toys and tools. Injection molding is ubiquitous in manufacturing and uses many different materials from polymer plastics to aluminum, copper and other metals. The plastic bottles and kitchen implements people use in everyday life are products of the injection process.

Because the metal molds are generally expensive to produce, Plastic molding is most economically used when thousands of pieces are being manufactured. Molds are made of hardened steel or, more recently, aluminum which is less expensive.

The Injection Process
Described very simply, molten plastic is injected into the mold under high heat and pressure. The goal is to have the molten plastic material evenly flow to all parts of the mold, creating an exact, consistent, solid plastic replica of the mold cavity. After a brief cooling cycle, the mold or tooling mechanically ejects the plastic part which then moves on through the manufacturing process. In the injection molding industry, this is a completely automated process that’s very fast and extremely efficient.

Rotational Molding
Rotational molding is yet another method of producing multiple products, most often made with a variety of plastic powders. This process is usually used in making hollow products such as traffic cones, canoes, kayaks, bicycle helmets and giant tanks used for water or chemical storage.

Like Injection molding, rotational molding had its roots in the 1940s. But it was not until the technology was more sophisticated and new polymer and plastic formulations became available that the rotational process became a mainstream manufacturing method.

Rotational Process
The two processes are quite different. Let’s consider, for example, a 300 gallon water storage tank made of polyethylene. Picture a master mold made of aluminum or steel. The plastics manufacturer pours poly resin powder into the mold that is fitted inside an oven. Once sealed, the mold is mechanically turned on at least three axes, moving much like a gyroscope. At the same time, the oven is raised to an appropriate temperature and the polymer – or other material – tumbles inside and slowly coats the inner walls of the mold, melting as it rotates.

Once the optimal temperature is reached, the mold is cooled. As the temperature of the mold itself falls, the product on the inside shrinks away from the inner walls and is easily removed. This is not always the case with injection molds that are often more difficult to successfully remove. The shrinking action of rotational molding is particularly desirable when the product is very large and awkward to handle.

Rotational molding is also more economical for some products because less material is used. In addition, the polymer that is left over from one mold can be used in another. The method itself is more streamlined than injection molding, which requires more interlocking parts.

Materials Improve and Expand
Most products made with the rotational molding method are from the polyethylene family. Other materials include nylons, polypropylene and PVC plastics. Some manufacturers have developed formulas that integrate the use of natural materials such as sand and chips of stone to make products.

Plastic and resin products are now an integral part of everyday life and supply us with items as tiny as paper clips and as big as storage tanks. As the industry developed, so too has environmental awareness about the safety and use of these petrochemical-based products. Today, materials can meet the specifications of FDA requirements, and other health and safety related regulations. Producers are also cooperating to create products that can be recycled.

Injection Molding Machines

Injection Molding Machines

The injection molding process was invented in 1872. Since then, the injection molding business and the plastic industry has ballooned into a multi billion dollar business venture. In fact, thirty two percent of plastics by weight are processed through injection molding. Injection molding has greatly helped in making the US economy boom because through it, cheap and durable consumer and industrial items essential to almost all industries is made possible.

Components of the injection molding machine

The injection molding machine converts granular or pelleted raw plastic into final molded parts through the use of a melt, inject, pack and cool cycle for thermoplastics.

A basic injection molding machine is typically composed of the following: injection system, hydraulic system, mold system, clamping system and control system.  The clamping tonnage and shot size are both used in identifying the dimensions of the injection molding machine for thermoplastics, which is the main factor in the whole process. Other consideration include rate of injection, pressure, design of screw, thickness of the mold and distance between tie bars.

Plastic Injection mold & Injection molding

Functions of the machine

The injection molding machine can be classified into three categories, namely: general purpose machines, precision/tight-tolerance machines and high-speed thin-wall machines. All three types require auxiliary equipment to function.  These support equipment includes dryers (resin), material handling equipment, granulators, mold temperature controllers and chillers, part-handling equipment and part-removal robots.

There are a lot of companies specializing in quality plastic molding, but they are not all the same. The best ones fast, flexible and customer driven both for large and small quantities. These companies usually have state-of-the-art facility with full scale thermoplastic and thermoset capabilities, computer-aided manufacturing, skilled machine operators and quality assurance team. Injection Molding provides detailed information on Injection Molding, Plastic Injection Molding, Injection Molding Machines, Custom Injection Molding and more.

Plastic Mold

Plastic Mold

Plastic has, quite literally, become the cornerstone of our society.  We make so many things from plastic that it is hard to imagine what our lives would be like if it was never invented.  With so many of our everyday products being made of plastic, it is easy to understand why plastic injection molding is such a huge industry.

Approximately 30% of all plastic products are produced using an injection molding process.  Of this 30%, a large amount of these products are produced by using custom Plastic Mold technology & injection molding technology.  Six steps are involved in the injection molding process, after the prototype has been made and approved.

Plastic Mold

The first step to the injection molding process is the clamping of the injection mould.  This clamping unit is one of three standard parts of the injection machine.  They are the mold, the clamping unit and the injection unit.  The clamp is what actually holds the mold while the melted plastic is being injected, the mold is held under pressure while the injected plastic is cooling.

Next is the actual injection of the melted plastic.  The plastic usually begins this process as pellets that are put into a large hopper.  The pellets are then fed to a cylinder; here they are heated until they become molten plastic that is easily forced into the mold.  The plastic stays in the plastic mold, where it is being clamped under pressure until it cools.

The next couple of steps consist of the dwelling phase, which is basically making sure that all of the cavities of the mold are filled with the melted plastic.  After the dwelling phase, the cooling process begins and continues until the plastic becomes solid inside the form.  Finally, the mold is opened and the newly formed plastic part is ejected from its mold.  The part is cleaned of any extra plastic from the mold.

As with any process, there are advantages and disadvantages associated with plastic injection molding.  The advantages outweigh the disadvantages for most companies; they include being able to keep up high levels of production, being able to replicate a high tolerance level in the products being produced, and lower costs for labor as the bulk of the work is done by machine.  Plastic injection molding also has the added benefit of lower scrap costs because the mold is so precisely made.Plastic Mould

However, the disadvantages can be a deal breaker for smaller companies that would like to utilize plastic injection molding as a way to produce parts.  These disadvantages are, that they equipment needed is expensive, therefore, increasing operating costs.

Thankfully, for these smaller companies, there are businesses that specialize in custom plastic injection molding.  They will make a mock up mold to the exact specifications, run it through the complete process and present the completed piece along with an estimate to complete the job to the customer.

Linda Moore writes on a variety of subjects including home ownership, travel, personal enrichment,