Our Products are suitable for powerful percussive drills and top hammers with high speed drifter, , such as Atlas Copco 282 rocket boomer, Atlas Copco 352 rocket boomer jumbo, AtlasCopcoD7roc, Furukawa HCR 1200, Tamrock, and Ingesoll Rand ECM660.R28 Tungsten Carbide Thread Button Bits for Drifting and Tunneling Name Code No. Thread Diameter Gauge Front Skirt Design Weight Threaded Button BitsQ7-36-R28R28365*8mm2*7mmStandard0.42Q7-38-R28R28385*8mm2*8mmStandard0.48Q7-41-R28R28415*9mm2*9mmStandard0.56Q7-43-R28R28435*9.5mm2*8mmStandard0.68Q7-45-R28R28455*10mm2*9mmStandard0.72Q9-45-R28R28456*9mm3*8mmStandard0.72Q9-48-R28R28486*9mm3*9mmStandard0.89Q9-51-R28R28516*10mm3*9.5mmStandard0.97 All tooth bit series passivation cycle is long, the wear life of about with the blade diameter titles bit wear life of 5-6 times, can save auxiliary working hours, reduce the physical labor of workers and accelerating the pace of work. Therefore different diameter of the taper connection and thread connection ball tooth bit is widely used in all kinds of hard and brittle rock with the drilling rig. Sweden's engineering and technical personnel that ball tooth bit and hydraulic drilling jumbo combination, is the best matching of modern drilling technology.In the recent 20 years, Thread Button Bit series development very fast, it is accompanied by hydraulic rock drill hole quickly save industry to improve the drilling speed and drilling auxiliary working hours.Compared with the traditional sheet bit, Column tooth drill bit with the advantage of grinding cycle length, drilling speed. Notes:Special sizes may be available upon request.How to order?Button Bit: Diameter + Thread + Skirt Shape + Face Design + Insert Configuration How To Choose Right Face Design And Body Skirt of R28 Tungsten Carbide Thread Button BitsButton Bit Face & Skirt Design Face & Skirt Design Application Flat Face:For Drilling in medium to hard and abrasive rockDrop Center Face:For drilling in medium hard, maximum hole deviation controlNormal Skirt:For drilling in very hard and very abrasive rock formation which is compactRetrac SkirtFor drilling in loose and broken or fissured rock where it is difficult to retrac the drilling string due to the hole collapsePACKING Key Words:R28 Threaded bit,R28 Tungsten Carbide Thread Button Bitsthread button bit,R28 button bitR28 Button Bit for for Drifting and TunnelingThread Button Bit for for Drifting and TunnelingButton Bit for for Drifting and TunnelingButton Drill Bit for for Drifting and Tunneling