Plastic Injection Molding – An Overview

There is a process referred to injection molding that ensures creation of different types of plastic products easily, quickly and in a cost-effective manner. Such items include bottle caps, power tools, toys, gears, pulleys, knobs, vales, washers, computer monitors, keyboards, furniture, car panels, and much more. This procedure according to the industry experts is cited to be an effective and economical way to manufacture bulk plastic items. The specification and size of each equipment is known to vary depending upon the products set to manufacture.

Invention of this process is credited John Wesley Hyatt. During 1868, he had developed billiard balls simply with the injection of celluloid into mold. Subsequently, injection molding machine was created with the incorporation of a plunger. James Hendry, another inventor during 1946 had modified Hyatt’s design to come up with machine with a screw.

 

Industries of today are found to produce plastic goods by employing both types of machines like the screw type and the plunger type. The major difference noticed between the two is the way plastic is placed within the given mold. The screw type equipment is much more popularly used due to its convenience. 

Plastic injection molding process is said to make use of plastic resins in pallet or granular form. Plastic selection varies depending upon the item planned to be produced, overall budget and its end use. Several types of plastics can be found in the market. However, not all are considered to be safe for humans. When injection molding is concerned, plastics which are used often are polycarbonate, polypropylene, polystyrene, polyvinyl chloride, polyamide, Delrin, Teflon and acrylic. 

Plastics are non-degradable and hence, are not environment friendly. But the process offered by the leading plastic injection molding supplier helps to eliminate waste and also allows reuse of same plastic. 

Plastic pallets or granules are fed into the machine hopper, which is actually a large container having an opening where plastic moves on to the heating cylinder. It is here that pallets get heated to a specific set temperature, thereby melting plastic. 

The screw or plunger forces melted plastic to move easily through the nozzle, right into the mold. It is quite opposite to the component planned to be produced. The mold might come with single or even more cavities to allow simultaneous production of various components. Molds may also be made by using durable, expensive steel. Aluminum and beryllium-alloy based molds are economical, but not durable. 

The right type of plastic and metal selection is of extreme importance for the mold, which is determined by the item that is planned to be produced, overall cost and desired durability. For plastic injection molding manufacturers, the normal practice followed is to make mold prototypes with inexpensive metal. To produce items in bulk, there are used accurately machined and durable molds. Molten plastic is cooled within the mold, thereby taking mold shape upon getting hardened. Mold is then thrown open for driving the component out and later packed to carry out additional operations or for shipping purpose. More information for plastic injection molding please check on http://www.pmold.com/

Report this Page