Hot plate welding

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Hot Plate Welding is a plastics welding process, utilizing heat of hot plate placed between the surfaces to be joined. The work pieces, pressed to the plate, heat up and soften. After a predetermined time the plate is removed, the parts are brought to the contact, pressed and fused together. Their polymer molecules are cross-linked when the work pieces cool down, forming a strong joint.

Hot plates are made mainly of Aluminum alloys. A hot plate is equipped with an electric heating elements and a thermocouple providing temperature control of the plate surface.

Applications

• Components of domestic electric devices (dishwashers, washing mashines, vacuum cleaners);
• Pipes;
• Automotive components (lights, fuel tanks, reservoirs, batteries).

Advantages

• Easily automated;
• High quality tight joints;
• Large and comples parts may be welded;
• Hot plate provides conforming the joined surfaces.

Disadvantages

• Long welding cycle: up to 20 sec. for small parts and up to 30 min. for large parts;
• Relatively large amount of flash (excess material) forms.