Plastic moulding techniques: everything you need to know
Plastics are polymers that can be molded into a variety of shapes and sizes using specific molding processes. They can be subjected to different types of processing to produce a wide range of products, from simple plastic bottles to complex car parts, up to the smallest plastic accessories. Over the years, technological evolution has led to the development of numerous plastic molding techniques, each with specific characteristics, advantages and fields of application. Each technique requires certain requirements in terms of equipment, raw materials and operating conditions, and the choice of the most suitable method depends on various factors such as the type of final product, production volumes, the required mechanical characteristics and construction costs.
In general, moulding processes can be divided into four main stages – plastic forming, cooling, part removal and finishing – but the stages may vary according to specific processing and production requirements. Understanding the differences between different molding methods is essential to optimize production processes, reduce waste and ensure high performance of plastic products.
Let us look more specifically at what is the moulding of plastics, which are the most common moulding techniques and their main characteristics.
What is plastic moulding
Plastic molding is an industrial process that allows raw plastic materials to be transformed into finished or semi-finished objects through the use of heat and pressure, shaping them according to predefined shapes within moulds. This process is based on the property of thermoplastic and thermosetting materials to soften or melt when subjected to certain temperatures, then solidify once cooled or chemically hardened.
The heart of the process is the mould, generally composed of two halves, designed according to the geometry of the part to be made: once closed, the mould receives the plastic in its molten state which is pushed or poured into it. Once the material completely fills the cavity and cools or hardens, the mold opens and the workpiece can be removed, ready for any subsequent finishing or assembly steps. This method enables the production of complex shaped components with high dimensional accuracy, minimising material wastage. In addition, plastic moulding is particularly appreciated for its versatility: it is suitable both for small-scale production and for the production of large quantities of parts in series, guaranteeing high quality standards and reduced production times. Thanks to these characteristics, moulding is one of the most popular technologies in modern industrial production.
Plastic moulding techniques: what are the main ones?
Moulding techniques are distinguished according to the characteristics of the material to be processed and the result that you want to obtain. Among the most widely used techniques are:
- injection moulding, which involves heating and then melting the plastic material, which is then placed under high pressure in a closed mould. Once the material has solidified, the mold can be opened and the finished product can be extracted. This moulding technique is carried out by means of an injection moulding machine. The plastic material is processed with very high temperature and pressure levels in order to ensure a greater smoothness of the material inside the mold;
- compression moulding, made with a special press on which an aluminum or steel mold is fixed. This molding technique is by vulcanization of the rubber and is useful for a wide range of applications because it allows to incorporate inserts in products of various types. Again, the process takes place at high temperature and pressure;
- blow moulding, mainly used for the production of hollow-shaped articles such as bottles, vials or containers. In blow molding the plastic material, in the form of granules, is heated to a pasty compound and then closed in a specific mold to give it its final shape. In this phase the air is blown which allows the plastic material to inflate, adhering perfectly to the walls of the mold. Once cooled, the part is taken out of the mould and is ready to be delivered to the customer or subjected to further processing;
- thermoforming, a special technique for moulding plastic materials by means of an appropriate thermoforming machine. Plates under pressure or vacuum can be used to complete the process. This molding technique is often used for the production of blisters, trays and containers for food use or panels in the automotive sector;
- rotary moulding is a printing technique used mainly for the production of hollow and large-sized plastic products (pots, furniture, bins). The plastic material is inserted into a mould and then rotated on two axes, so that the plastic adheres to the walls. At this point the product can be cooled and then extracted.
Plastic moulding for third parties: discover the service offered by Beschi!
Plastic moulding for third parties is a solution increasingly sought by companies that want to outsource production, maintaining high quality standards and optimizing time and costs. Thanks to the continuous search for cutting-edge solutions and a suitably equipped press park, Beschi is able to ensure an efficient plastic moulding service, addressed to all companies that have the need to make customized plastic parts or parts.
The company stands out for its ability to manage the entire production cycle, from raw material to finished product, providing an efficient, precise and flexible service. Turning to Beschi, each company in possession of its own molds can count on a technologically advanced production plant, equipped with a press park ranging from 80 to 400 tons, including 4 two-component plants.
The added value of the service offered by Beschi lies in the department dedicated exclusively to quality control, where specialized personnel performs visual checks on each individual item. This approach ensures that each component meets the expected dimensional and functional tolerances, meeting the most stringent demands in terms of performance and reliability.
A further strength is represented by the immediate availability of a wide range of raw materials, including OMO and COPO PP, ABS, PE, PS, PVC, Nylon, Acetalica and other technical plastics. This organization allows Beschi to respond quickly to production requests, even in the case of emergencies or peaks in demand. The internal logistics allows deliveries to be managed on time, thanks to a fleet of trucks and shared planning with the customer.
Beschi’s stamping service is particularly appreciated in the textile sector, where the company has a long experience, but also addresses companies active in the most diverse industrial sectors. The company is also able to provide a custom-made mould design and production service, ensuring the manufacture of high quality products that are resistant and durable over time. The objective is to satisfy the requirements of each customer, who is followed in every stage of the production process, from design to the realization of the finished product.
