Pneumatic Hot Plate Welding

Description

Hot plate welding, also called heated tool welding, is a thermal welding technique for joining thermoplastics. Hot plate welding machines are generally operated by pneumatic, hydraulic or electromechanical controls. Machines can be configured to perform welds with the faying surface in either the horizontal or vertical position. Longer components such as pipes are more commonly welded in the horizontal position whereas moldings with internal fittings such as a starter battery are welded in the vertical position. A heated tool is placed against or near the two surfaces to be joined in order to melt them. Then, the heat source is removed, and the surfaces are brought together under pressure. Hot plate welding has relatively long cycle times, ranging from 10 seconds to minutes, compared to vibration or ultrasonic welding. However, its simplicity and ability to produce strong joints in almost all thermoplastics make it widely used in mass production and for large structures, like large-diameter plastic pipes. Different inspection techniques are implemented in order to identify various discontinuities or cracks.