KNSH-130BRS 40mm x 155mm Core Drill Bit for Industrial Applications

New, not used, the crown pin, nominal diameter 130 mm, the shape of the head part - with a core notch, the connection of the crown-roller, the shape of hard alloy-half-sphere, the angle of inclination of the peripheral row of pins - 40 degrees, the peripheral row - 8 pins at 14 mm, frontal row - 7 pins at 14 mm, the number of blow holes - 1, length 208 mm, weight 8.2 kg. The durability of the crown is not less than 80 metres when drilling in rocks and ores with hardness factor f =14...16 on the scale of Prof. Protodyakonov.