Welding Plastic

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Plastic Welding is at the heart of plastic fabrication.

Our welding equipment includes sheet and pipe fusion welders, extrusion welders and hot air welders – some of the most advanced plastic welding equipment in Australasia.

Hot Air Welding

Hot Air Welding is the traditional welding process used in plastic fabrication. The work piece and a plastic welding rod, typically 3mm, are heated and softened with a jet of hot air as they are pressed together. Thin materials can be welded reasonably efficiently and welds can be made in tight corners and around complex shapes. However, weld quality is very dependent on the operator and productivity is low. We have a number of workshop and field hot air welders.

Pipe Fusion Welding

The process for Pipe Fusion Welding is, in essence, identical to Sheet Fusion Welding, the one significant difference is the geometry of the weld. Pipe Fusion Welding is widely used to join PE pipe for water, waste water and gas reticulation. Our pipe fusion welders are ideal for industrial work where pipes up to 355mm, are commonly used.

Sheet Fusion Welding

Our sheet fusion welder is the only one of its type in New Zealand and allows us make very large tanks. It is used to join PE, PP, PVC and PVDF sheets between 2mm to 50mm thick and up to 4m wide in a flat or 90 deg join. Plastic fusion welds are of very high quality, often as strong as the parent material, and productivity is high.

Socket Fusion Welding

Socket Fusion welds are used to join pipe and are made by heating and softening the outside of the pipe and the inside of the pipe socket with a heated tool. The pipe and socket are pressed together to form a strong joint. Electro-fusion socket joins are made in a similar way, using pipe sockets that have a built-in heating coil. The joint is assembled and a specialised power supply is used to heat the coil and fuse the pipe to the socket. We use both processes to join PP, PE and PVDF pipe.

Extrusion Welding

Extrusion welders are hand held plastic extrusion machines which, when pressed against the work, allow a large section of softened plastic to be extruded into the weld joint. Fillet, butt, or lap welds, up to 35mm wide, can be laid down in a single pass. Because of this, productivity is typically 5 times that achieved with hot air welding. In addition, because the weld material is completely plasticised and laid down in a single pass, weld strength is typically higher than hot air welds. Extrusion Welding is ideal for tank manufacture. We have four extrusion welders suitable for all situations.

More about the welding process

Fusion Welding is also known as Butt Fusion Welding, Mirror Welding, Heated Tool Welding, or Hot Plate Welding. Of all the welding processes it gives the best quality welds. It is the most productive welding method and it is the least reliant on operator skill.

In a carefully controlled cycle, the edges of two plastic sheets are pressed against a heated bar, softened and then pressed together to produce a very strong durable, accurate and neat join. Our Wegener Sheet Fusion Welder will weld plastic sheets from 2mm to 50mm thick and up to 3m wide in a straightforward automated process. Welds can be either flat, or 90 degrees allowing a wide range of finished geometries. In addition, cylinders and rectangles up to 3m long can be closed to form tank barrels, rectangular duct and tank sections and numerous other items. Rectangular sections with internal dimensions from 100mm x 200mm to 3m x 12m and cylinders from 300mm to 5m are practical. All of the common thermopolymers including PP, PE, PVC and PVDF can be welded with our Sheet Fusion Welder.