Check hydraulic oil on sight level gauge on hydraulic tank, pumps would be making noise if oil level is low. Make sure all hoses are connected properly and not damaged. Check couplings and make sure they are plugged in properly.
[pdf] The utilization of pneumatic DTH hammer drilling is the most efficient approach to rescue miners. The previous DTH hammer's impact model was simplified and the analysis of impact parameters was incomplete, hi.
[pdf] Pneumatic down-the-hole (DTH) hammer has been extensively used in air drillings through hard and ultra-hard geological formations. Numerical modeling can offer close observation on the working behav.
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