XTC GD40 series DTH drilling hammer

2 3/8" Reg pin 4-inch High Air Pressure DTH Hammer GD40 DHD 340A with Foot Valve 4-inch DTH Hammer GD40 is similar with DHD 340A with foot valve, used on drilling hole range from 110mm to 135mm. GD40 air pressure range is from 1.0Mpa to 2.5Mpa, the recommended impact rate is 27Hz under 17Mpa. The air consumption is 6.5m3 at 1.0Mpa and 14m3 at 2.4Mpa.  It has the following advantages,1. Valve air distribution, more reliable.2. Simple design of the piston, long working life3. More energy transfer, faster drilling speed, lower air and oil consumption.4. Fewer internal parts, simple structure, longer service life, lower failure rate and easier to maintain because all the parts are heat treated.5. Easy to disassemble because the top sub, the drive chuck and the external cylinder are connected by multi-step thread.   Model GD40 Foot Valve No Recommended Rotation Speed 35-65r/min Air Pressure High 1.0-2.5Mpa Impact Rate under 1.7Mpa 27Hz Air Cons…