G-Force Nova GFN12000 N120 Shank
Hammer Specifications - G-Force Nova N120 Shank


Features:
- No foot valve required
- Easy to service
- Special heat-treated alloy piston for long life, Rockwell hardness 60
- Minimum loss of performance when injecting foam or water
Item # | Description | Part # |
1 |
Back Head | GFN12001 |
2 |
Back Head Washer | GFN12002 |
3 |
Back Head O-Ring | GFN12003 |
4 |
Buffering Washer | GFN12004 |
5 |
Make-Up Rubber(Buffering) | GFN12005 |
6 |
Air Check Valve | GFN12006 |
7 |
Air Check Valve Spring | GFN12007 |
8 |
Air Guide | GFN12008 |
9 |
Air Guide Plug (Choke) | GFN12009 |
10 |
Air Guide O-ring | GFN12010 |
11 |
Air Distributor | GFN12011 |
12 |
Air Distributor O-Ring | GFN12012 |
13 |
Cylinder | GFNN12013 |
14 |
Wear Sleeve | GFNN12014 |
15 |
Piston | GFNN12015 |
16 |
Piston Stop Ring (Buffering) | GFN12016 |
17 |
Bearing O-Ring | GFNN12017 |
18 |
Bearing | GFNN12018 |
19 |
Bearing Stop Ring (Key) | GFN12019 |
20 |
Bit Retaining | GFNN12020 |
21 |
Bit Retaining O-Ring | GFNN12021 |
22 |
Chuck Bushing | GFNN12022 |
23 |
Chuck Washer | GFN12023 |
24 |
Chuck (Drive Sub) | GFNN12024 |
- | O-Ring Kit | GFN12025 |
Specifications
Length (w/o drill bit) | 72.36" |
Outside Diameter | 10.35" |
Weight (w/o bit) | 1499 lbs. |
Cylinder Bore | 8.267" |
Piston O.D. | 7.33" |
Piston Stroke | 5" |
Piston Weight | 254 lbs. |
Hole Sizes | 11 7/8" - 17 1/2" |
Air Pressure Consumption | 100 psi - 350 psi |
Wrench Size | A/F 7.95" |
Connection | Std. 6 5/8" API Reg Pin |
Air Consumption Chart
PSI | 100 | 150 | 200 | 250 | 300 | 350 | 400 |
CFM with blank choke | 418 | 672 | 974 | 1,268 | 1,548 | 1,756 | - |
All Hammers come Fitted with blank Choke located in the Air Check Valve
Hammer Service Log
Wear Sleeve / Piston Clearance
Part | New Dimension | Discard Clearance | |
Wear Sleeve | A | 8.27" | greater than or equal to 0.010" |
Piston OD | B | 8.26" |

Inner Cylinder / Piston Clearance
Part | New Dimension | Discard Clearance | |
Cylinder ID | C | 5.98" | greater than or equal to 0.010" |
Piston OD | D | 5.978" |

Distributor Probe / Piston ID Clearance
Part | New Dimension | Discard Clearance | |
Distributor Probe OD | F | 2.47" | greater than or equal to 0.010" |
Piston ID | E | 2.48" |

Bearing - Piston OD Clearance
Part | New Dimension | Discard Clearance | |
Bearing ID | H | 6.10" | greater than or equal to 0.010" |
Piston OD | G | 6.09" |

External Wear
Description | Wear Limit |
Wear Sleeve Reverse Dimension | 9.88" |
Wear Sleeve Discard Dimension | 9.72" |
NOTE: Chuck should be replaced when wear transfers to wear sleeve. |
Lubrication
G-Force Series Hammers are precision-made tools and should be treated as such. Only the highest quality lubrication should be used and a constant flow of oil must be maintained at all times. Recommended lubrication amount 1/3 Pint per 100 cfm per hour.Recommended Grades of Lubricant
ESSO MATEX CASTROL SHELL MOBILE |
AROX EP 150 RDO 302 RD OIL DP 100 AIR TOOL OIL 2 A 320 ALMO NO. 5 |
Recommended Pull Down
Minimum @ 100 psi - 5600 lbs. | Maximum @ 350 psi - 9900 lbs. |
Missile Warranty will be voided by the following:
Welding on Wear Sleeve.
Heating Case with a Torch.
Gripping Wrenches across Threads.
Hammering on Casing.