Plastics Welding

Plastics Welding: Process of joining similar or dissimilar materials with similar flow behaviour by thermal means.

Joining of Thicker sections  welding, Thin films  s  ealing.

1. When two plastic parts are bonded together by heating, melting and resolidification process is referred as Welding.

2.  Generally this is achieved when two similar plastics are bonded together, such as PS to PS, Nylon to Nylon, to PP to PP, or when compatible plastics are bonded together, such as ABS to PS or SAN to ABS etc. 

3. The plastic welding is confined to thermoplastic polymers because these materials can be softened by heat where as thermosetting polymers once hardened cannot be softened again on heating. 

3. The heat required for welding thermoplastic polymers is less than that required for metals.

4. Plastic welding processes can be divided into two groups: 

1. Processes involving mechanical movement – ultrasonic welding, friction welding, vibration welding.

2. Processes involving external heating – hot plate welding, hot gas welding and resistive & implant welding.

Direct heat welding

1. Hot plate or Heated Tool Welding

2. Hot air welding / Hot gas welding 

3. Resistance wire welding

4. Thermostacking

Indirect Thermal welding

1. Ultrasonic welding

2. Spin/ Friction welding

3. Vibration welding

4. Dielectric heating or High frequency sealing.

5. Laser Welding.