Numa CHALLENGER 6 User manual

CARE & MAINTENANCE
INSTRUCTIONS
©2023 Numa All Rights Reserved
P.O. Box 348 •646 Thompson Road •Thompson, CT 06277 USA
US Toll Free: (800) 356-NUMA •Tel: [phone] •Fax: [phone]
E-mail: [email protected]
Website: www.numahammers.com
Patents 4,530,408 4,919,221 4,962,822 5,205,363 5,984,021 5,992,537 6,021,856 7,422,074
6

6
TABLE OF CONTENTS Page
Section I General Description ........................................... 1
Functional Description ............................................................. 2
1. Backhead ........................................................................ 2
2. Check Valve ................................................................... 2
3. Check Valve Spring........................................................ 2
4. Check Valve Housing..................................................... 2
5. Compression Rings ......................................................... 2
6. Feed Tube Retainer......................................................... 2
7. Feed Tube Housing ......................................................... 2
8. Feed Tube ........................................................................ 2
9. Choke .............................................................................. 3
10. Piston ................................................................................ 3
11. Case ................................................................................. 3
12. Bit Bearing........................................................................ 3
13. Wear Spacer.................................................................... 3
14. Disc Springs...................................................................... 3
15. Washer ............................................................................. 4
16. Retainer............................................................................ 4
17. Bit Retaining Rings........................................................... 4
18. Chuck............................................................................... 4
19. Thrust Washer................................................................... 4
Section II Maintenance................................................................. 5
Disassembly .............................................................................. 5
Inspection.................................................................................. 8
General Assembly.................................................................. 11
Feed Tube Assembly .............................................................. 11
Hammer Assembly ................................................................. 11
Section III Parts Identication ................................................... 13
Challenger 6 Exploded View................................................. 13
Challenger 6 Part Number Reference .................................. 13
Section IV Air Consumption Chart.......................................... 14
Section V Lubrication................................................................... 15
Section VI Storage......................................................................... 16
Short Term................................................................................ 16
Long Term ................................................................................ 16
Restarting................................................................................. 17
Section VII Button Bit Maintenance ....................................... 18
General.................................................................................... 18
Sharpening .............................................................................. 18
Section VIII Challenger 6 Recommended Spares........... 19

04/23/10
WARRANTIES AND REMEDIES
LIMITED WARRANTY
Numa warrants that the Product will be new and free from defects in material and workmanship
under normal use as contemplated by this Contract for a period of six (6) months from the date of
shipment.
Except for the foregoing warranty, Numa disclaims all warranties and representations wherever
made, including warranties of merchantability, durability, length of service, or tness for a particular
purpose.
Any alteration or modication of the original product without the express written consent of
Numa will void this warranty.
REMEDY
If, during such warranty period, Buyer promptly noties Numa in writing of any defect and
establishes that the above warranty is not met, Numa shall either repair or replace the Product or
credit the customer, as it deems necessary to meet the warranty.
Such repair, replacement, or credit of Product shall constitute complete fulllment of Numa's
obligation under this warranty, and upon the expiration of the original warranty period, all of Numa's
obligations hereunder shall terminate.
LIMITATION OF LIABILITY
Numa shall not be liable to Buyer whether in contract, in tort (including negligence and strict
liability), under any warranty or otherwise, for any special, indirect, incidental or consequential loss
or damage whatsoever, including (without limitation) loss arising from delay, cost or capital and loss
of prots or revenues. The remedies set forth in this Contract are exclusive, and the total cumulative
liability of Numa under this Contract or for any act or omission in connection therewith or related
thereto, whether in contract, in tort (including negligence and strict liability), under any warranty or
otherwise, is limited to the price paid by Buyer for the Product.
The WARNINGS, CAUTIONS and NOTES used throughout the text of this
instruction book are dened as follows:
WARNING A specic procedure or practice that must be strictly followed,
or a specic condition that must be met, to prevent possible
bodily harm.
CAUTION A specic procedure or practice that must be strictly followed,
or a specic condition that must be met, to prevent damage
to the equipment.
NOTE Important supplemental information.
Numa®,Champion, and Patriot
are registered trademarks of Numa.

03/09/23 Page 1
6
SECTION I
DESCRIPTION
GENERAL DESCRIPTION
The Challenger 6 is a valveless, pneumatically operated tool designed to utilize Numa 6" to
8-1/2" (152 mm to 216 mm) diameter bits in rock formations under a wide range of operating
conditions.
The Challenger 6 hammer design incorporates a hardened, reversible case. The simple
design of the Challenger 6 provides performance and dependability without sacricing tool
life.
The Challenger 6 is designed for universal applications using air pressure from 150 PSI
to 500 PSI (10.2 Bar to 34.5 Bar) with compressors ranging in size from 425 CFM (201 Litres/
Second) or more. When drilling conditions require supplementary hole cleaning, additional
hole cleaning air can be passed through the hammer by utilizing an interchangeable choke.
All standard hammers shipped from Numa have a blank choke installed. Refer to page 14
for correct choke selection and pages 7 & 11 to facilitate the removal and the installation of
the choke.
Challenger 6
Weight w/o Bit 258 lbs. (117 kg)
Outside Diameter 5-3/8" (137 mm)
Hammer Length:
Shoulder to Shoulder 52" (132 cm)
Shoulder to Bit Face 55" (140 cm)
Backhead API Thread 3-1/2 API REG
Table 1-1 General Hammer Specications
6" (152 mm) 52 lbs. (24 kg) 6-3/4" (172 mm) 55 lbs. (25 kg)
6-1/8" (156 mm) 52 lbs. (24 kg) 7" (178 mm) 63 lbs. (29 kg)
6-1/4" (159 mm) 53 lbs. (24 kg) * 8" (203 mm) 69 lbs. (31 kg)
6-1/2" (165 mm) 53 lbs. (24 kg) * 8-1/2" (216 mm) 72 lbs. (33 kg)
* Not for use in production drilling
Table 1-2 General Bit Specications
NOTE
NUMA 6" TO 8-1/2" (152 MM TO 216 MM) BITS ARE AVAILABLE IN CONCAVE,
CONVEX OR FLAT FACE DESIGNS WITH LARGE AIR FLUSHING HOLES AND CHIP
WAYS. OTHER SIZES MAY BE AVAILABLE UPON REQUEST.

Page 2 03/09/23
6
FUNCTIONAL DESCRIPTION
1. BACKHEAD
The backhead connects the hammer to the drill rod. It is threaded into the top end of
the case with a large cross section thread form and into the drill rod with a standard
3-1/2 REG API thread. Other threads are available upon request. Wrench ats are
provided for disassembling.
2. CHECK VALVE
The check valve maintains pressure in the hammer when the air supply has been shut
off. The pressure in the hammer balances the hydrostatic pressure in the hole thereby
preventing contaminants from entering the hammer.
3. CHECK VALVE SPRING
The check valve spring provides tension under the check valve to keep it closed. It is
compressed as the air is turned on.
4. CHECK VALVE HOUSING
The check valve housing guides the check valve and the check valve spring. The
main air supply is directed to the feed tube through ports located in the check valve
housing.
5. COMPRESSION RINGS
Two compression rings, one between the check valve housing and the feed tube
housing and one between the feed tube and the feed tube housing, keep the internal
hammer parts tight.
6. FEED TUBE RETAINER
The feed tube retainer keeps the feed tube seated in the proper location. The feed
tube retainer also allows air to ow to the piston and feed tube.
7. FEED TUBE HOUSING
The feed tube housing is aligned in the main bore of the hammer. It is located by a
matching 45° angle in the case bore and is held in position by the backhead, check
valve housing and compression ring combination. The feed tube housing locates and
aligns the feed tube.

03/09/23 Page 3
6
8. FEED TUBE
The feed tube supplies the main air into the chambers located in the piston. The feed
tube collar seats against the feed tube compression ring which locates against a
shoulder in the feed tube housing. The feed tube is held in place by a feed tube snap
ring located above the feed tube collar. The long bearing surface design insures
alignment in the feed tube housing.
9. CHOKE
The interchangeable choke is located in the tip of the feed tube and is held in place
with a press t. A set of four chokes is supplied with each hammer. By installing the
correct choke, the hammer can be ne tuned to the compressor package.
10. PISTON
The piston functions as the only moving part in the hammer, controlling the operational
air cycle. The percussive action of the piston striking the bit transfers the energy through
the bit in order to fracture rock formations.
11. CASE
The case is designed to contain the internal parts which make up the hammer assembly.
The case is reversible and is hardened to resist wear and to extend life in abrasive
conditions.
12. BIT BEARING
The bit bearing guides the bit to insure proper alignment between the piston and the
bit. The bit bearing is pressed into the chuck end of the case and locates against a
matching 45° angle in the case bore. The bit bearing provides a seal for the main air
supply.
13. WEAR SPACER
The wear spacer is not installed in a new hammer. It is located in the chuck end of the
case between the bit bearing and the disc springs. The wear spacer is used to take
up any space that can no longer be compensated for by the disc springs due to disc
spring compression fatigue in the bottom end of the hammer.
14. DISC SPRINGS
The four disc springs are located in the chuck end of the case. They are held in place
between the bit bearing and the washer. The disk springs are compressed as the chuck
is screwed into the case. They are designed to expand and maintain a tight assembly
as the internal hammer parts wear.

Page 4 03/09/23
6
15. WASHER
The washer is located between the disc springs and the retainer. The washer is used
to provide an area to seat the disc springs.
16. RETAINER
The retainer is a hardened steel ring with a 3/4" (19mm) space to allow it to be compressed
when installing it in the case. The retainer is installed in the chuck end of the case and
prevents the disc springs and washer from falling out when the chuck, the bit retaining
rings and the bit are removed.
17. BIT RETAINING RINGS
The bit retaining rings are designed to allow the bit to move between the drilling and
cleaning positions and prevent the bit from coming completely out of the hammer. The
bit retaining rings consist of two matched halves and are held together with an o-ring.
18. CHUCK
The chuck threads into the bottom of the case with a large cross section thread form.
It has internal splines that mesh with the splines on the bit body to transmit rotation.
19. THRUST WASHERS
Two brass thrust washers, one located between the backhead and the case, and one
between the chuck and the case, provide for easy disassembly.

03/09/23 Page 5
6
SECTION II
MAINTENANCE
DISASSEMBLY
•If at all possible, the backhead and chuck should be broken loose on the drill rig; this
is much easier than trying to do so after the drill has been removed from the drill rig.
CAUTION
USE CAUTION WHEN HANDLING DOWN HOLE HAMMER PARTS. NUMA HAMMER PARTS
ARE MANUFACTURED FROM HARDENED, HEAT TREATED MATERIALS. DROPPING OR
STRIKING THESE PARTS MAY CAUSE SEVERE DAMAGE. STRIKING THE HAMMER PARTS
WITH HAMMERS, CROWBARS OR LIKE INSTRUMENTS WILL VOID THE WARRANTY
•Maintenance should be performed in a clean environment.
• Tools needed: hammer stand, chain vise, 2" (51mm) diameter brass rod, snap ring
pliers, press, a drift pin and a small screwdriver.
•Clean the outside of the hammer. This will insure a good surface to clamp on.
•Place the hammer horizontally on a hammer stand and secure the hammer with a
chain vise. Place the chain vise on the area of the case where the bit bearing is housed
when working on the chuck end of the hammer. When working on the backhead end
of the hammer, place the chain vise on the area of the case where the check valve
housing is housed.
CAUTION
THE ACCEPTABLE CLAMPING AREAS START 5" (127MM) FROM EITHER CASE END,
TO AN ADDITIONAL 3" (76MM) BEYOND THIS POINT. PLACING THE CHAIN VISE
ON THE AREA OF THE CASE WHERE THE PISTON CYCLES CAN DISTORT THE CASE,
RESTRICT PISTON MOVEMENT AND VOID THE WARRANTY.
•Unscrew and remove the backhead from the case. Remove the backhead o-ring from
the backhead and thrust washer.
•Remove the check valve, the check valve spring and the check valve housing from
the backhead end of the case.
•Remove the compression ring from the base of the check valve housing.
•Remove the feed tube retainer.
•Unscrew and remove the chuck, bit and the bit retaining rings from the case.

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6
•Remove the thrust washer from the chuck.
•Remove the bit retaining rings o-ring from the bit retaining rings.
•Use the snap ring pliers to remove the retainer, then remove the washer and the four
disc springs.
•Using a 2" (51mm) diameter brass rod, slide the piston against the feed tube assembly
and push the feed tube assembly out the backhead end of the case.
•Slide the piston out the backhead end of the case.
•Removal of the bit bearing is not necessary for routine maintenance. If necessary,
insert the bit bearing press plate into the backhead end of the case, with the small
diameter toward the case bore. Using a 2" (51mm) diameter brass rod, slide the bit
bearing press plate to the chuck end of the case until it rests against the bit bearing.
Using a press, apply pressure to the 2" (51mm) diameter brass rod and force the bit
bearing press plate and the bit bearing out of the chuck end of the case. Refer to
gure 2-1 for bearing spacer dimensions.
N6 Bearing Spacer/Press Plate
Figure 2-1
3/64R3/64R
1/32 CHAMFER
1/32 CHAMFER
3 PLACES3 PLACES
3.235-3.250
3.235-3.250
2 1/2
2 1/2
1
1
4.200-4.215
4.200-4.215
7/8
7/8
45°
45°