flat in order to achieve the least amount of porosity in the weld and also to increase the weld's strength. Fillet welding make up about 80 percent of the connection despite being weaker than butt welds. The reason it is used more often is because fillet welds offer more room for error with much larger tolerances. Fillet welding is not a type of butt weld despite its similarities. Butt welding plastic A butt welding machine, commonly referred to as a poly welder or fusion machine, is required to heat polyethylene pipe segments under pressure for a period of time. To perform a butt weld correctly and consistently, you will require a butt welding machine capable of aligning the elements to be welded, shaving their ends smooth and parallel, uniformly melting the ends of the pipe under various pressures, then pushing the ends together at a controlled pressure for a specific period. A correctly performed butt weld on plastic pipe will create a bond far stronger than the segments themselves. Uses of the poly material has grown significantly in recent years due to its light weight, cost-effective production and ability to last 100+ years underground. Butt welding on plastic is done to create pipe systems typically used in water distribution and gas networks. Types of butt welding Flash Flash butt welding is used with machinery and connects multiple pieces of metal together that are miss matched in size and shape. These different sizings can oftentimes cause for breaks in welding process. High voltage current is applied in order to connect the metal pieces together by applying it to both the components known as flashing in order to join them together. Resistance This weld joins the two pieces of metal together by heat that comes from the pressure due to the metals being held together at a preset force. Resistance butt welding is used on joints that are of similar shape and size and often the weld is performed in one movement unlike flash welding. Types of butt joints There are many different types of butt welding joints and they all are named with their particular shape. The joint also known as a square groove weld has many different forms in order to connect pieces of metal together and are all capable of bearing loads. There are many different types of joints such as lap joints, tee joints, butt joints, and also