Atlas Copco SMARTROC D65 TIER 4 FINAL, Maintenance Manual

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SmartROC D65 Tier 4 Final 14 Options
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Check for any uneven wear on the inserts as this can indicate that the main air seals are
leaking.
It is essential the inner pipes included in components fitted in the system after the blow-
down valve are in good condition. Inner pipes in bad condition can impact negatively on
test flow and cause extra wear to the blowdown valve.
There is an indicator hole in the cylinder housing. If oil or air starts to leak from this hole, it
means the cylinder rod seal is leaking and must be replaced.
CAUTION
Risk of injury
Serious damage or lethal injuries can occur if changes or repairs are performed on this
system by unauthorised persons.
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We recommend always getting in touch with a qualified service engineer before per-
forming any work on this system.
14.3.6 Fault finding in the event of air leakage
If the down-the-hole rock drill appears to be obtaining less pressure than expected, or if
there are difficulties with sample return, the most likely cause will be missing O-rings or
holes in an inner tube.
A circular cover plate is used during fault finding (test sub - check in spare parts list for cor-
rect part number) that blocks the flow of compressed air between the inner and outer tubes
so that compressed air is contained. Look in the spare parts list for the correct part num-
ber.
A drill rod or rotation head is screwed on by hand and the air is switched on. If air is flowing
from the centre of the cover plate then this indicates that O-rings are either missing or are
in poor condition, or that there is a hole in one of the inner tubes above the cover plate. If
the leaking air hisses out then the problem is probably missing O-rings, if the air is blowing
out then it is probably a hole in an inner tube.
By using the method of elimination, the adapter can be moved up or down on the drill string
in order to determine which component is generating the problem. As each step in the test
is taken, one component is removed and checked until you have found which one is de-
fective. The problem must be rectified, i.e. the part must be replaced or repaired, and a test
performed to confirm that this was the only problem. It is important not to assume that a
particular component is faultless - all must be tested in a logical sequence until the problem
is found.
14.3.7 Conversion to normal drilling
If there is a requirement to convert from RC drilling to normal drilling, there are several
ways to achieve this, each with a different scope:
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A normal down-the-hole rock drill is used on RC tubes together with an adapter for API
threads. A stop plug is also fitted in the inner tubes at the down-the-hole rock drill or at
the spar adapter in order to prevent air from flowing out through the inner tubes. This is
not an option in the long-term because the increased vibration tends to damage the in-
ner tubes.
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The inner tubes can be removed from the RC tubes. The deflectors and sample hoses
can also be removed. If the sample hose is removed then the deflectors must also be
removed and vice versa.