For those less familiar, plastic injection molding can be defined as a manufacturing process for creating products from plastic materials. The plastic is fed into a heated barrel, mixed, and forced into a mold cavity where it loses heat and solidifies with the shape of the mold cavity.
The plastic injection molding industry has had a fascinating history. The plastic material was invented in Great Britain in 1861 by Alexander Parkes and he called it Parkesine. People found Parkesine to be extremely useful because it could be heated, molded, and made to retain its shape when cooled. In 1868, American inventor John Wesley Hyatt developed a plastic material he called celluloid that was an improvement over parkesin in that it could be processed into a finished shape.
Along with his brother Isaiah, Hyatt patented the first machine in 1872. However, this machine was too simple compared to machines widely used today. Current machines consist of a material hopper, an injection ram or screw-type plunger, and a heating unit. In addition, some advanced machines have a built-in sampling and approval process for strict quality control.
The plastic injection molding industry began to grow in the 1940s when the World War created a demand for inexpensive, mass-produced products. Six years later, American inventor James Watson Hendry built the first screw injection machine, which provided greater control over injection speed and the quality of items produced.
Over the following decades, the industry evolved and began producing a wide range of plastic items ranging from combs and buttons to a variety of technology products for various industries including automotive, medical, aerospace, consumer products, toys, etc. . Although there are several different methods used in the manufacture of plastic items, injection molding is the most popular.
Plastic is durable, lightweight, and unlike metals, it is resistant to corrosion and wear. Some amazing advantages of this technique are high production capacity, repeatable high tolerances, low labor costs, minimal scrap losses, and almost no need to finish parts after molding. Of course, this technique has its own drawbacks: the process involves a large investment in equipment, potentially high operating costs, and the need to design castable parts.
However, the increasing demand for plastic products has led to the rise of the plastic molding industry. Today, you will find the use of plastic from everyday products to those used in critical industrial sectors such as aviation and building construction, among others.
Injection molding is the most common method of manufacturing plastic parts. It is ideal for mass production of the same product. The demands for plastic products are growing at a dizzying pace and today we need machines in almost every industry sector.
Previously, the machines were operated manually and automatically, but now the machines can be operated computerized. While earlier versions are simply known as plastic injection machines, the latest one is called CNC plastic machine. The CNC plastic machine has managed to solve some of the problems associated with conventional molding processes.
