Product Description
This cold-pressed four-button family covers source-listed 32, 36, and 42 mm gauges for tunnel rounds, mine development, and smaller rock-drill holes. The range allows the hole diameter to be selected for the pattern while retaining a compact carbide face. Review the use under the mining and exploration application archive and classify the rock through the hard formation archive. The family is intended for competent rock; none of the listed gauges makes it an overburden or soil-drilling system.
The filename combines a 42 mm mine bit, a 32 mm ballistic carbide reference, a 36 mm tapered bit, and a cold-pressed four-button construction. Those details support a 32–42 mm family record, but they do not prove that every size has an identical face or connection. The body is described conservatively as alloy steel with pressed carbide buttons. Taper dimensions, button shape by gauge, flushing layout, and skirt length remain unverified. Each ordered diameter therefore requires its own drawing and rod-fit review rather than relying on the family image.
Keep operation within 1,000–3,000 lbf/in of diameter and 25–60 RPM. A smaller gauge may need less total load even though the normalized WOB range is unchanged, so settings should be calculated from actual diameter. Hard and abrasive rock call for inspection of pressed-button retention, chipping, and gauge loss. No flow is stated because the source does not define the drill, rod bore, or flushing medium. The limitation is that the image joins several sizes in one description. Geological context can be checked through the U.S. Geological Survey.
