Water Powered Percussive Downhole Hammers – Energy savings and Productivity-PPT Presentation

PPT Presentation

Pdf Summary

The presentation describes water-powered down-the-hole (DTH) hammers and their advantages over conventional air-powered DTH systems. Water DTH uses roughly one-quarter the energy, reduces vibration-related risks to nearby structures, performs better below the groundwater level, and produces straighter holes. In one comparison, average hole deviation was 1.3% with Wassara Water DTH versus 19.2% with Air DTH.<br /><br />Water DTH can also improve jet-grouting productivity in challenging ground containing boulders, hard layers, soft strata, and water-bearing zones—conditions that can limit rotary drilling or cause problems for Air DTH. A jet-grouting setup combines a Wassara water hammer with a monitor and triple-wall drill tube carrying grout, air, and water.<br /><br />Two case studies illustrate the productivity gains. At the Brenner Base Tunnel, Water DTH drilling for 31-meter grout columns took 45 minutes per hole, compared with 90 minutes using Air DTH. For construction of shafts at Rio de Janeiro’s Gavea metro station, where ground conditions included sand, stones, boulders, and hard rock, a jet-grouting hammer drilled each hole in 23 minutes, versus 80 minutes with a conventional rotary monitor.

Keywords

water-powered DTH hammers

air-powered DTH

energy efficiency

reduced vibration

groundwater drilling

hole deviation

jet-grouting productivity

Brenner Base Tunnel

triple-wall drill tube

shaft construction