Deflashing

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   Deflashing


Many moulded products can be separated from their excess moulding scrap by use of scissors, cryogenic deflashing or buffing. The latter process has to be carried out with caution for those products which are bonded to metal substrates, because excessive generation of heat will result in loss of the bond integrity and product failure.


 Buffing Machines


These units can vary from simple wire brushes rotating at high speed to carborundum belts. Heat generation in the rubber product is the main problem with these units.


 Cryogenic Deflashing Units

Cryogenic deflashing of rubber is commonly carried out using liquid nitrogen as the temperature depressant, although some smaller units can be operated using solid carbon dioxide as the low temperature medium.

Correct determination of the required time in the deflashing unit is necessary otherwise the bulk of the product can become brittle with fractures occurring in the mass of the product.





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