Electrofusion welding machine, also called electric heating welding machine, is a special tool for electric welding of PE pipe. It mainly provides stable welding voltage or welding current for welding, and detects and controls the welding process to maximize the welding effect.
This electrofusion welding machine is used for the electrofusion welding of PE and PP electrofusion pipe fittings, which is an adjustable voltage source. Its output voltage and welding time can be continuously adjusted in a wide range to meet the welding requirements of different electrofusion pipe fittings.
This kind of electrofusion welding machine is used for the electrofusion welding of PE electric heating band, and its output generally adopts effective value constant current output. The output current and welding time can be continuously adjusted in a large range to meet the welding requirements of different electric heating bands. At present, the pipe fitting electrofusion welding machine is mainly used for the electrofusion welding of pressure PE and PP pipes, while the electric heating band electrofusion welding machine is mainly used for the electrofusion welding of non-pressure PE and PP straight or corrugated pipes.
In fact, theoretically speaking, whether it is an electrofusion pipe fitting or an electric heating band, it is a resistive load. As long as the welding thermal power requirement is met, there is no essential difference between the voltage type welding machine and the current type welding machine. For example, a PE electric heating band with a resistance of 6 ohms is welded to a 1200mm corrugated pipe, and the welding current given by the fusion welding machine manufacturer is 20A. At this time, 20A constant current welding and 120V constant voltage welding have exactly the same effect. However, it should be pointed out that the electrofusion pipe fittings belong to low resistance load, while the electric heating band belongs to the high resistance load. The output voltage of the commonly used pipe fitting electrofusion welding machine is generally 39.5V, and the maximum output voltage of the upward adjustment is 44V, which can only be used for low resistance. The load cannot output the welding voltage of 120V, so it cannot be used for the welding of electric heating band. It is for this reason that the electric heating band electrofusion welding machine was produced.
Some people may ask, why can't the output voltage of the pipe fitting electrofusion welding machine be designed to be higher so that it can be used both for the welding of electrofusion pipe fittings and the electric heating band? Seemingly it is OK, but for the phase-controlled electrofusion welding machine, when the voltage is increased, the power factor will become very low when welding electrofusion pipe fittings, so this is actually impossible.