VARI-STEM -- VARISTEM

VARI-STEM contains the explosive energy within the rock mass where it belongs!

VARI-STEM Plugs work by creating a blocking effect within the drill hole by wedging the stemming material between the drill hole wall and our plug. Upon detonation of the explosives, the plug is forced upward into the stemming material and "locks up". The the plug locks up, the explosive gases and energy are prevented from traveling (venting) up through the drill hole, and instead are contained within the rock mass for milliseconds longer than non-plugged blasts!

Increased Fragmentation, Fracturing and Cap Rock Breakage. Reductions in Fly Rock, Air Blast, Stemming Ejection, Dust, Noise and Oversized Rock. These are all direct benefits and results of containing the blast energy within the rock mass for milliseconds longer than normal, simply by using VARI-STEM.

DESIGN FUNCTION

VARI-STEM’s Patented GEAR Design:

• Prevents plug collapse in undersized holes or when forced over jagged rocks.
• Makes the plug detonator cord (tube or wire) friendly. The numerous vertical grooves on the outside diameter of the plug prevent the detonator cord from being crushed, nicked or pulled into the drill hole during insertion. (The cord will simply slip into one of the vertical grooves.)
• Gives structural strength to the plug.

Easy To Install:

These plugs should be inserted point-down. Using a standard loading/charge pole, simply push the plug to the ANFO or Emulsion. It literally takes seconds!!!

Besides reducing average rock diameter in the muck pile, VARI-STEM saves equipment and labor costs by reducing the quantity of oversized cap rock. It is possible to reduce stemming height using VARI-STEM, allowing more ANFO for greater cap rock breakage. VARI-STEM and ANFO are cheap compared to secondary breakage costs (chemical vs. mechanical costs).

And note the Pattern Spread - Holcim Aggregate, showing savings in drilling fewer holes for the same fragmentation