Versadrill’s KMS0.3 diamond core drill rig uses a Variable Volume Reservoir from Sobacor Inc. to trim 40% of the weight from the rig’s hydraulic system. This is important because the rigs are transported by aircraft, which would otherwise require having them disassembled for transport, then reassembled at the work site.
These rigs require powerful drives that are compact and light weight. So, naturally, the need for high power density makes hydraulics the drive technology of choice. But this posed a challenge — how to make the drive even more compact and lightweight.
As with most hydraulic drives, Versadrill’s hydraulic systems used a fixed-volume reservoir. The current trend of specifying smaller reservoirs had already been followed, so the challenge was to reduce the reservoir’s size even further without reducing performance. Company officials found a solution in a variable volume reservoir from Sobacor Inc., Bois des Filion, Quebec. Sobacor developed its Variable Volume Reservoir (VVR) to reduce standard reservoir size and weight, but the VVR also reduces the amount of fluid needed for a system, fluid disposal cost, and potential for contamination.
Substantial weight reduction
Versadrill’s previous KMS0.3 drills used a conventional 200-l reservoir. Now, however, they operate with only a 6-l VVR, which reduces the weight by nearly 285 lb. This amounts to a 40% weight reduction of the entire hydraulic system because the reservoir is not only smaller and lighter, but much less fluid is needed. Furthermore, performance has not been affected — and in some cases has actually improved.