Sonic drilling employs a high frequency, rotary vibratory drill that is designed to fluidize, overburden, and fracture rock faces. This process results in seamless casing advancement or continuous core samples that can be accessed without the application of drilling fluids.
[pdf] Fill the reservoir with air tool oil or 10W equivalent for 9 lb and 15 lb class. Use rock drill oil for the 38 lb and 60 lb class tools. Check all nuts and bolts to ensure they are tight on the tool. Make sure retainer locks into place. Replace retainer and springs if worn.
[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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