Plastic doors, commonly made from materials like uPVC (unplasticized polyvinyl chloride), are manufactured through a precise process that focuses on shaping and joining specific profiles. This involves taking extruded plastic lengths and assembling them to form the door's structure.
The Core Process: Fabricating the Door Frame
The creation of a plastic door primarily revolves around the preparation and assembly of its frame components, which are typically long, hollow profiles. The process involves several key stages:
1. Cutting the Profiles
The first step is to take the long plastic profiles and cut them to size according to the specific dimensions required for the door frame. Precision is crucial at this stage to ensure the final door is square and fits the intended opening.
2. Carrying Out Machining Operations
Once cut, the individual profile pieces undergo a number of machining operations carried out on them. These operations involve using specialized tools to create necessary features on the profiles. This is done to enable the finished product to have hardware fitted (like hinges, locks, and handles) and for water drainage paths to be formed. Effective drainage is vital for external doors to prevent water ingress.
3. Joining the Frame Components
After cutting and machining, the prepared profile pieces are assembled to create the door frame. They are then joined together. This joining process typically utilizes one or both of the following methods:
- Heat Fusion Welding: This is a common technique, especially for uPVC. The ends of the profiles to be joined are heated to a molten state and then pressed together. As they cool and solidify, they fuse, creating a strong, seamless corner joint. This is referred to as heat fusion welding.
- Mechanical Fixings: In some cases or for specific parts of the frame, mechanical fasteners like screws or brackets may be used to connect the profiles. This is covered by the term mechanical fixings.
These joining methods are used to form the desired configuration of product, resulting in a rigid and durable door frame ready for the next stages of manufacturing.
Finishing the Door
Once the frame is fabricated, panels (solid plastic or composite) or glass units are installed within the frame's sections. Finally, the previously prepared hardware (hinges, locks, handles) is fitted into the machined slots and holes, completing the door assembly.
This systematic approach, particularly the precise cutting, machining for functionality, and robust joining of profiles, forms the foundation of how plastic doors are made.
