Polyurethane Foam - Foam Sealant
Consolidation of Coal and surrounding strata
Often malfunctions occur and large cavities, several metres high can be formed.
The low viscosity of the reactive PU foam mixture, the volume increase in the blowing reaction (through CO2 formation), the fast cure time, the elasticity and adhesive properties of the reacting foam are all features that make PU foam the preferred consolidation agent.
There is very little temperature increase in the surrounding coal due to the exothermic nature of the PU reaction and there is no danger of ignition.