Procedures for Re-certification of Bonding Agents

It is prudent to have bonding agent test procednres so that products are not needlessly discarded and also that bonds are not made with products that are below an accepted level or standard. 

The bonding agents should be examined at six monthly intervals or other intervals as defined by a customer to suit its requirements, to determine that the products are in a liqnid state and have not chemically reacted and solidified. 

Where viscometers are available the viscosity should be recorded. Viscometers such as the Brookfield LVT are recommended. Flow cups may also be used although they are difficult to calibrate. Bubble tubes such as Gardiner Tubes can be used for clear products. 

If a process is viscosity sensitive this should be noted and a standard drawn up so products are always used within the prescribed limits. 

Products that have not gelled or solidified and are covered by points test interval, record, viscosity and viscosity sensitivity may be used by a customer for a further period of 6 months. Other pre-defined periods may be used for test intervals. 

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