Process Comparison
Comparison between Shell Mold Process and α-set Process
| Part | Shell Mold Process | α-set Process |
|---|---|---|
| PROCESS OUTLINE | Method to heat a metal model at 250~350°C, coat the release agent of silicon resin on it, and invest the model in a molding material which has combined SiO2 of about 140~200mesh with thermosetting synthetic resin for molding | Method to add a self-hardening binder to artificial ceramic sand and make a mold with mixed casting sand, and leave it in the air to harden or harden it with hardening agent |
| ADVANTAGES |
Ability for even unskilled worker to make the shell with minimal training Ability for mass production Ability to apply to foundry of all metals High precision of casting |
Natural hardening at room temperature for reduced time and drying cost Not required of skill for molding Excellent collapse after pouring molten metal Available for mass production Available to recycle the casting sand in use (More than 90%) Currently most efficient and advanced sand-foundry technology |
| Limitation |
Not economic for small quantity of foundry as mold needs to be made High cost for foundry as the price of resin is relatively high Limited specification available for manufacturing |
Molding conditions (Added amount of resin and hardener) react sensitively to pot time and formation time according to the conditions of surrounding environment Difficult to select casting sand Necessary to concern on the value of the loss of ignition (LOI) |
