NPK revealed the first hydraulic hammer in its new GHD series in March and has since followed up with four more models.
The next-generation mid-range GHD series attachments are for excavators ranging from 10 to 39 metric tons. The hammers feature a new speed selector valve that allows operators to match tool impact frequency to the material type and switch from anti-blank fire to blank fire. A slip-fit tool bushing is also new for easier maintenance.
The series is replacing the GH breakers, and the new models share the same tool and mounting kit as the previous generation for compatibility.
Hammer Highlights
Other features on the new NPK GHD series include:
- Simple, two-moving parts design.
- Gas-fired piston for increased hammer efficiency.
- NPK Rubber Mount System to help increase energy transfer while decreasing pin and bushing wear in the carrier.
- Ports for automatic bushing lubrication and air for underwater use.
- Tie rods enclosed in grease chambers to reduce harmonic vibration and extend service life.
- Quick-change tool system with single round retainer pin.
- Variety of tool configurations available including chisel, blunt tool, moil point and core tool.
The New GHD Lineup
The new NPK GHD lineup consists of the following models:
GHD-6 – For excavators weighing 10 to 14 metric tons, it delivers 2,000 foot-pounds of impact energy and 450 to 1,000 blows per minute. It requires 20 to 40 gallons per minute of hydraulic oil flow at 2,175 to 2,465 psi.
GHD-7 – For excavators weighing 13 to 21 metric tons, it delivers 2,500 foot-pounds of impact energy and 400 to 900 blows per minute. It requires 26 to 48 gallons per minute of hydraulic oil flow at 2,600 psi.
GHD-9 – For excavators weighing 18 to 25 metric tons, it delivers 3,000 foot-pounds of impact energy and 500 to 900 blows per minute. It requires 40 to 53 gallons per minute of hydraulic oil flow at 2,600 psi.
GHD-10 – For excavators weighing 21 to 30 metric tons, it delivers 4,000 foot-pounds of impact energy and 430 to 800 blows per minute. It requires 44 to 55 gallons per minute of hydraulic oil flow at 2,300 to 2,600 psi.
GHD-12 – For excavators weighing 25.5 to 39 metric tons, it delivers 5,500 foot-pounds of impact energy and 400 to 780 blows per minute. It requires 45 to 58 gallons per minute of hydraulic oil flow at 2,650 psi.
