Atlas Copco Secoroc QLX Series Operator Instructions Manual page 18

PROBLEM CAUSE
Low 5. Exhaust tube projection
penetration/ too long
high pressure
6. Valve action impeded
7. Worn Tail Seal
Low 1. Lack of oil
penetration/
low pressure
2. Worn drill clearances
3. Damaged valve seat
4. Incorrect Airselect setting
1. Worn piston
Drill running
off bottom
2. Excessive water injection
3. Debris (cuttings, mud)
between chuck and bit spline
Chuck hard to 1. Poor gripping
loosen
2. Conditions
Compressor 1. Incorrect Airselect setting
unloading
2. Excessive water injection
3. Mud Rings
Hammer 1. Mud or dirt in hammer
won't start
2. Broken exhaust tube
3. Broken internal parts
Component 1. Piston cracked through
failures
18
REMEDY
5. Check projection vs. specifications repair tube.
6. Check nose of backhead for corrosion other deposits that can interfere with the
smooth cycling of the valve. Remove deposits if present.
7. Replace Tail Seal.
1. Insure lubricator is working and hammer is getting coated
with oil. Check bit blow ports for oil film.
2a. Inspect piston for wear particularly on large diameter just beneath scallops.
This is the most sensitive diameter. Check other diameters; tail bore seal and tail
diameter for wear. Compare all to specification.
2b. Inspect guide diameter for wear. Compare with
specification and replace if necessary.
2c. Check cylinder bore for wear. Compare to
specification and replace if necessary.
2d. Check casing bore for wear. Compare to
specification and reverse or replace if necessary.
2e. Check bearing bore for wear. Compare to
specification and replace if necessary.
3. Inspect valve seat surface for damage or wear
which could cause leakage. Replace valve is suspect.
4. Readjust Airselect.
1. Inspect large diameter of piston for wear. Leakage past the large diameter can
cause the piston to cycle when off bottom.
2. Try reducing water injection level. Water inhibits the air venting process which
is needed to shut the hammer off.
3. Clear debris.
1a. Don´t grip over threads.
1b. Insure tong jaws are sharp.
2. Try using breakout washer.
1. Correct Airselect setting.
2. Reduce water injection rate.
3. Clear mud ring. Increase water injection. Consider adding foam.
1. Disassemble, clean, inspect and repair hammer. Check for
proper function of check seal.
2. Replace tube. Inspect Bearing and Chuck.
3. Replace broken parts.
1a. Lack of lubrication could cause frictional cracks in large diameter. Check
lubricator and insure oil film is developed on
bit blow holes.
1b. Wrenching over wrong location distorts casing and causes frictional rubbing
with piston. Apply tong wrench pressure in correct location.
1c. Fighting or getting stuck in hole heats and distorts casing bore causing
frictional heat and cracks on piston. Flood tool with water when stuck.
1d. Collaring on an angle or feeding hard through voided, faulted or broken
ground can cause casing to distort and rub piston causing cracks. Use light feed
when going through tough conditions.