ROCSIL ® FOAM LS1 is the industry’s leading cavity fill product providing the most cost effective solution to underground coal mines for this critical application.

ROCSIL ® FOAM LS1 is a two component phenolic resin product used for cavity filling, air and gas sealing, fire fighting and stabilisation of highly fractured strata. It’s most common use is to fill roof cavities formed by longwall roof falls.

The mixing of resin and catalyst in a volume ratio of 4:1 produces an immediate foaming reaction followed by a rapid expansion of the product to as much as 35 times its original volume. After expansion, ROCSIL ® FOAM hardens in approximately 5 minutes.

Prior to the introduction of ROCSIL ® FOAM, foaming cement type products were used for the recovery work. The phenolic foam material is far superior to foaming cement on many critical areas such as faster application rate, improved safety, higher foaming ratios and reduced shuttering to contain the fill material. WM through their technology partner Weber mining in France identified the benefits of ROCSIL ® FOAM in early 2000 and embarked on an extensive research and development program to introduce the product to Australia. Whilst numerous large multinational companies around the world claimed phenolic resin too hazardous to introduce to the Australian underground coal industry, WM and Weber thought otherwise and have since proved its worth with over 1300 successful ROCSIL ®FOAM applications in Australia and NZ.

ROCSIL ® FOAM is a LOBA (Arnsberg) approved product and has effectively eliminated foaming cements for cavity filling in Australian underground coal mining.

ROCSIL® FOAM can also be used in a wide variety of applications beyond just cavity filling. This includes sealing underground heatings and mine fires, coal rib support, and surface subsidence crack repairs.


  • Proven cavity fill product in most Australian longwall mines
  • Extremely fast, safe, cavity filling operation up to 50m 3/hour
  • High expansion rate means smaller quantity of product and materials to be delivered to underground location at 70% less than foaming cement
  • Minimal formwork required due to high expansion, fast setting product
  • Excellent compressive strength
  • Expands in situ providing positive support to the cavity
  • Minimal leaks due to high foaming and fast setting time
  • Will not block or seize the AFC
  • The product will not burn or propagate flame
  • Can also be used for injection where there are large voids with in the strata.


  • Stabilisation of fractured and unstable ground
  • Sealing against water ingress
  • Strata sealing air / gas leakage
  • Where spontaneous combustion of the coal is a risk
  • For more details on the ROCSIL ® FOAM application method see our cavity filling services page.


Density at 20oC (g/cm3) 1.2 1.5
Mixing Ratio (in volume) 4 1
Storage Temperature (oC) 12 12
Ambient Temperature (oC) 15 25
Reaction Time (min.) 5:00 2:00
Compressive Strength at 10% Deformation (MPa) 0.1 –0.2 0.1 –0.2
Foam Factor 26-35
Yield (kg/m3) 40-45
Shrinkage <1%
Fire Classification Fire resistant. No flame propagation

The above data are values obtained in laboratory tests. They may vary according to site application conditions.

Metarock (ASX: MYE) is a leading Australian mining services group providing a diverse range of services and products to underground operations across the country.

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All Rights Reserved. ABN: 96 142 490 579

P: +61 2 4904 8222
E: enquiries@wilsonmining.com.au
A: 16 Metro Court, Gateshead NSW 2290

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