I am seeking a trainer who has the expertise to teach a group of machinists and technicians on Plastic Injection Moulding? If you are one or if you know someone in Malaysia or Singapore please email me the details.
December 20, 2010
November 3, 2010
Does anyone know how to calculate cycle times for a product on Plastic Injection Moulding Machine?
I have all the data like product size, weight, melt flow rate of PP resin, injection rate of machine, plasticizing rate, mould open close rate. Am I missing something here?
September 13, 2010
All You Need To Know About Plastic Moulding
We cannot imagine a world without plastics. Plastics have found their importance in almost all application ranging from household items to complicated research equipments. Though there were controversies that the plastics pose a threat to the environment, the advancements in plastic manufacturing technologies have given birth to the eco-friendly plastics. Plastic manufacturers can now recycle and create new plastic products out of the used plastics. You will be well aware of the fact that injection moulding is widely used to manufacture the plastic products. Today’s plastic moulding is very much advanced and very different from what was originally invented. Just keep on reading the article to know all about the plastic moulding techniques.
A Little History
Plastic moulding is not a new concept developed in the 21st century. Moulding plastics into useful products exits since the origin of manmade plastic in the year 1851. The process of heating plastics and melting the molten material to obtain the shape of the mould is the basic concept behind plastic moulding. Though the concept of plastic moulding remains the same today, this technology has seen many advancements. Plastic moulding received huge importance during the period of Second World War due to the demand for the plastic medical equipments. Infact the plastic manufacturers where struggling to meet the demand for the plastic products during this period. This is period when the plastic moulding industry got a new shift towards development.
Current Plastic Moulding Techniques
Though the main concept of plastic moulding remains the same, the equipments used by the plastic manufacturers have changed a lot. With the integration of latest computer technologies the production rate of plastic moulding is greatly increased today. Unlike the olden days only when only fresh plastic materials were moulded to useful products, today with environmental awareness on the rise, plastic moulding concentrates on using recycled materials. Moreover, the advancements in plastic moulding technology has made it possible to manufacture products in any complicated shapes.
The Applications Of Modern Plastic Moulding
The applications of plastic injection moulding are virtually unlimited. Starting from simple plastic carry bags to complicated lifesaving devices – every plastic product manufactured today are through plastic injection moulding. Some of the common applications of plastic moulding are the manufacturing of products such as packaging bags, automobile parts, beverage cans and bottles, computer accessories etc.
The Future Of Plastic Moulding
You will be well aware of the fact that the use of plastics is banned in certain areas of all countries. People think that this may end the plastic manufacturing as environmental pollution is a major concern today. However, with the introduction of the recyclable plastics, the plastic industry has got a rebirth. Afterall, as already said, we cannot imagine a world without plastics.
R.E Davison is known in industy by two leading brands: RED Composites and Gloda Manufacturing and offer services in 2 major areas including plastic moulding. RED Composites for Thermoset plastic and plastic injection moulding for metal pressing and deep drawing for both the Australian and export market.
April 20, 2010
Medical Plastic Injection Moulding – Procedure and Products
In 1868, John Wesley Hyatt developed the first plastic injection mold, and the plastic injection moulding process. He used the plunger method to successfully inject hot, liquid celluloid, often called the first thermoplastic, into a split-die mold. This process was little changed until James Hendry built the first screw plastic injection mold in 1946. Today, nearly all industrial and medical plastic injection moulding processes use the screw method.
Plastic moulding is a very methodological and technical process. Thus it needs experts in this type of manufacturing business for it to meet the safety terms and to be competitive in the market. A very scientific and systematic mechanical study is first made before going into this endeavor. Here I have discussed some known plastic injection moulding process that can help you to understand the various ways it is done for industry specific plastic products.
1. Injection Moulding.
Examples of applications: Medical plastic laryngeal mask components, laboratory products, extraction systems, toys, aircraft undercarriage components, kitchen utensils, bottle caps, and cell phone stands.
In Injection Moulding, melted plastic is forced into a mold cavity. Once cooled, the mold can be removed. This plastic injection moulding process is commonly used in mass-production or prototyping of a product. Typically this process is used to produce plastic mouldings where the relatively high tooling cost can be justified by low unit costs and tolerances which cannot be achieved by other moulding processes.
2. Blow Moulding.
Examples of applications: Automotive, Toys, Recreational, tubes and containers, Medical, Housework Appliances
The process is divided into three steps: injection, blowing and ejection. Blow moulding is like plastic injection moulding except that hot liquid plastic pours out of a barrel vertically in a molten tube. The mold closes on it and forces it outward to conform to the inside shape of the mold. When it is cooled, the hollow part is formed. Equipments needed in setting-up a blow moulding business are relatively higher than injection moulding.
3. Compression Moulding.
Examples of applications:Â Automotive exterior panels especially for commercial vehicles, Radio & appliance knobs, ash trays & electrical parts.
In this type of plastic moulding, a slug of hard plastic is pressed between two heated mold halves. Compression moulding usually uses vertical presses instead of the horizontal presses used for injection and blow moulding. The parts formed are then air-cooled. Prices of equipments used for compression moulding are moderate.
4. Film Insert Moulding.
Examples of applications: FIM can be used to apply clear scratch-resistant hard coats, logos, text and graphics in any color or combination of colors to plastic parts prior to injection molding.
This plastic moulding technique imbeds an image beneath the surface of a molded part. A material like film or fabric is inserted into a mold. Plastic is then injected.
5. Gas Assist Moulding
Examples of applications:Â Flat panels for office equipment, Computer enclosures, Furniture, i.e. tabletops, Automotive panels, Domestic appliances – e.g. fridges.
Also called gas injection moulding is used to create plastic parts with hollow interiors. Partial shot of plastic is then followed by high-pressure gas to fill the mold cavity with plastic.
6. Rotational Moulding.
Examples of applications:Â All kinds of plastics mostly hollow Plastic Parts.
Hollow molds packed with powdered plastic are secured to pipe-like spokes that extend from a central hub. The molds rotate on separate axes at once. The hub swings the whole mold to a closed furnace room causing the powder to melt and stick to the insides of the tools. As the molds turn slowly, the tools move into a cooling room. Here, sprayed water causes the plastic to harden into a hollow part. In this type of plastic moulding, tooling costs are low and piece prices are high. Cycle time takes about 40-45 minutes.
7. Structural Foam Moulding.
Examples of applications: Typical products are large trash containers, freeway sand safety containers and in-ground housing for water systems.
Structural foam moulding is a process of plastic injection moulding usually used for parts that require thicker walls than standard injection moulding. Inserting a small amount of nitrogen or chemical blow agent into the plastic material makes the walls thicker. Foaming happens as the melted plastic material enters the mold cavity. A thin plastic skin forms and solidifies in the mold wall. This type of plastic moulding can be used with any thermoplastic that can be injection molded.
8. Thermoforming.
Examples of applications: Clamshells, Trays, Blisters, Displays, Guards, Covers, Totes, Shields, medical plastics
In this plastic moulding process, sheets of pre-extruded rigid plastics are horizontally heated and sucked down into hollow one-piece tools. When the hot plastic solidifies, its shape conforms to that of the mold. Tooling costs are usually low and piece prices vary on the machinery.
Goodbrand Plastics provides Plastic Injection moulding services to diverse sectors with specialisation in Medical plastic injection moulding from our site in Sandbach, Cheshire, northwest England.