Extruders: Using Extrusion Welding, plus Benefits and Advantages
Extrusion is a popular welding option when it comes to joining and welding plastics in any required industry. Here is everything you need to know about using extrusion welding, along with its advantages.
What is Extrusion Welding?
Extrusion is a commercial option of plastic-joining, namely the welding of PP and HDPE. It is one of the options to weld thermoplastics and composite materials. It was first developed in the 1960s as an improvement upon hot gas welding.
The process of extrusion welding includes manual work by a qualified welder, although it is possible to establish an automatic extrusion welding process if a continuous welding application is needed, due to high volume, for example.
During extrusion welding, molten thermoplastic is shaped and extruded into the same material as the parts which are being welded. It is prepared as a relevant joint between these parts. This process is achieved via a plastic extruder gun, which has a welding head with a nozzle used for hot air, and an extruder which pushes the filler material out.
The joining surfaces are then heated and joined with molten or plastic filler material.
Where can Extrusion Welding Be Used?
Examples of where extruders can be used in plastic welding are for tanks and pipe sections, based mainly in the manufacture of large thermoplastic fabrications. This is because these fabrications require a large volume weld in a single pass, which extrusion welding can achieve.
Extruders can also be used in environmental applications. Specifically, this could be the joining of lining on various materials, such as roof coverings or material used in the construction of landfills.
Welding with extruders is becoming increasingly popular in agriculture and water engineering applications, especially within land drainage systems and sump tanks.
What Are Extruder Benefits?
Welding with extruders has a host of benefits. These include:
- Achieving a high rate of deposition with filler material welded into a joint. This means that the time taken is significantly decreased. Compared to a hot gas welding alternative, extrusion welding is actually at least five times faster.
- Strong fusion welds. The areas which extrusion welds can be stronger than other parts of the fabricated polymeric part.
- High quality welds. Through the use of pre-sets on the welding machine to regulate the welding parameters, consistent, high-quality welds can be produced at a high rate.
- Extrusion welding uses a continuous weld bead. This means that the welding can be performed in a single pass, compared to hot gas welding, which uses more than one pass. This makes it quicker and more convenient.
- The fabrication time is much quicker than with hot gas welding. This is due to the increased number of materials which is dispensed during a pass with extrusion welding.
- The maximum weld strength is higher. Compared to hot gas welding, extrusion welding provides closer and more direct control of the parameters within the welding, which means it is able to weld at a stronger capacity.