Casting Ring Liner

Casting Ring Liner

 

A ring liner is placed inside of the casting ring. Earlier asbestos liners were used. Its use has been discontinued due to the health hazard of breathing its dust.

Functions of Ring Liner:

• Allows for mold expansion. (Acts as a cushion)
• When the ring is transferred from the furnace to the casting machine, it reduces heat loss as it is a thermal insulator.
• Ring Liners permits easy removal of the investment after casting.

A casting ring liner is placed under the casting ring. The casting ring liner should be 3 mm short at one end to allow proper contact between the investment and casting ring once the liner is burnt out.

Types of Ring Liners:

• Asbestos ring liner: Discontinued using due to health hazard
• Non-asbestos ring liner:
  • Fibrous ceramic aluminous silicate
  • Cellulose
  • Ceramic–cellulose combination.

Functions of Ring Liners:

• Ring Liners leads to mold expansion.
• Ring Liners acts as a thermal insulator when the ring is transferred from the furnace to the casting machine.
• Ring Liners causes easy removal of investment after casting.