Manufacturing of plastic products

Plastics products are one of the most widely used goods in today’s life. So with every rise in consumption of plastic products, the demand for plastic machine tools and plastic manufacturers are increasing at a rapid rate too. To meet the growing demand of plastic products, manufacturers are using various advance tools and technologies so as to deliver as much as they can without compromising the quality.

Plastic manufacturing are basically done by two different processes. One is plastic injection molding process and the other one is plastic extrusion molding process. Both the process are widely used and accepted within the industry but have different uses and outcomes.

Plastic injection molding process:

Plastic Injection Molding process is primarily used for manufacturing different parts from plastics. The first step of injection molding includes feeding plastic pellets into the hopper, which is turn feeds the pellets into the barrel. After doing so, the barrel which contains a reciprocating screw or rams injector is then heated. This reciprocating screw plays a vital role by crushing the pellets and making it easier for the plastic to be liquefied. Toward the front of the barrel, the reciprocating screw propels the liquefied plastic forward and thereby injecting the plastic directly into the empty mold by passing it through a nozzle. Unlike the barrel, the mold is kept cool to harden the plastic into correct shape. The mold plates are help closed by using large plate. These movable plates are then attached to a hydraulic piston, which in turn puts pressure on the mold itself. Clamping the mold shut prevents plastic from leaking out, which would create deformities in the finished pieces.

Plastic extrusion molding process:

Extrusion molding is another widely used method for manufacturing plastic products. Extrusion molding is quite similar to injection molding and used for manufacturing pipes, tubes, straws, hoses and other hollow pieces. In this method, plastic resin is feed into a barrel. Here the plastic is meant to be liquefied. After liquefying, a rotating screw attached within extruder machine propels the liquefied plastic into the mold, which contains a tube-shaped orifice. The size and shape of the tube determines the size and shape of the plastic piece. The liquefied plastic then allowed to cool and then is fed through an extruder. The extruder flattens the plastic and forms the piece into its final shape.


Describing these processes is quite easy but the things are not so easy in practical life. A number of complications can arise during the plastic manufacturing process. Burned parts due to excess temperature, deformities, surface imperfection and brittle parts are the issues that arises manufacturing complications and can cause a serious problem if not taken care properly. In addition to these, if the reciprocating screw becomes jammed or is not rotating fast enough, liquefied resin will remain in the barrel too long and become scorched. Surface imperfections and deformities occur when the surface temperature of the mold is uneven, if the molds are not clamped tightly enough or if the melting temperature is too high. Brittle pieces are formed when not enough liquefied resin is injected into the mold or if the plastic hardens before the mold can be filled. Regular testing and calibration of injection and extrusion molding machines is critical to ensure that the process runs smoothly.


Author’s Bio:

I am a freelance writer, born and brought up in an industrial belt, passionate about industrial machines. I salute plastic extruder machine manufacturer for their contribution in industrial sector.