DD Grout Plugs provides simple and easy-to-use high-pressure plugs to the underground diamond drilling industry.
Diamond drilling in underground mines often occurs below the water table and holes venture out beyond the drawdown cone. High-pressure water is commonly encountered, and yet there are no pressure rated plugs available to block the water – until now. The Hydra-Barb Technology plugs are the only diamond drilling plugs available industry-wide with working pressure ratings.
Water pressure in underground diamond drill holes comes from the drawdown cone around the mine. Natural rock has a permeability through the cracks and fissures in the rock. As mines dewater their operations, this creates a drawdown cone around the operation to keep the mine workings dry.
Diamond drilling however often goes beyond the drawdown cone, or connects with conduits – cracks, fissures, and water channels, that allow water from beyond the drawdown cone to pass into the diamond drill hole. The flow may be as fast as a fire hydrant, or as slow as a trickle – but the flow is not indicative of the pressure. The pressure is related to the difference in height between the diamond drill location and the water table feeding it. The common assumption of low flow means low pressure is incorrect.
Geologists in charge of diamond drilling operations will need to understand what water pressure their drillers may encounter and ensure that plugs rated for the water pressure are used. Getting it wrong risks flooding with uncontrollable inflows. The most recent high profile flooding event occurred at the Naica Mine in Mexico, home of the spectacular crystal cave. In 2015, the 700ktpa mine flooded and is no longer in production.
The initial Hydra-Barb high-pressure diamond drilling plug was developed to allow diamond drillers to quickly and easily block off high-pressure water. They are simply pushed in place with the drill rods, then the drill rods are retracted. No rotation, no complicated threads or taping up of the plug – they just work.
The Hydra-Barb is rated to 1,000 psi (69 Bar) with a factor of safety of 2:1.