Atlas Copco SMARTROC D65 TIER 4 FINAL, Maintenance Manual

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SmartROC D65 Tier 4 Final 14 Options
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All inner tubes are sealed with O-rings in order to separate the high-pressure air from re-
turn air. It is critical that these O-rings are in place and in good condition. When you access
them it is prudent to replace any O-rings whether or not they are worn.
14.3.4 Blow adapters
Blowdown adapter
Certain RC machines from Atlas Copco are equipped with a blowdown system from Met-
zke. It is possible to screw blowdown system loosely on the drill string on RC rigs without
one. The blowdown adapter directs the compressed air down through the inner tubes and
in this way clears any blockages and forces return air to the outside of the drill pipes. We
recommend contacting an Atlas Copco service engineer before making any changes to the
rig.
Blow-up adapter
DANGER
Serious injury or death
There are blow-up adapters on the market that direct the compressed air upwards
through the deflectors and the sample hose to the cyclone. It is very easy to subject the
sample hose to damage, which may also cause injury if anyone is in the vicinity. Due to
this you are advised against using blow-up adapters.
14.3.5 Metzke Blowdown Valve
The Metzke Blowdown Valve directs the compressed air down through the inner tube and
so clears away any blockages and forces return air to the outside of the drill pipe.
WARNING
Serious injury
The blowdown valve works with air under high pressure. Air under high pressure is ex-
tremely dangerous.
u Remove or isolate the air or hydraulic inputs before service or maintenance.
u The valve has internal moving parts that can be dangerous due to pressure forces. Do
not position any part of the body or any objects in the valve ports during tramming.
A daily visual inspection should be carried out in order to check for abnormal wear, hy-
draulic leaks and damaged components. Replace parts when necessary.
The Metzke Blowdown Valve does not have any lubricating points.
The spool sleeve, upper and lower inserts, and seals will wear over time - this is normal.
With this in mind, regular inspections must be made through the top of the valve. It is es-
sential that these parts are replaced before being worn. Any further wear will cause consid-
erable damage to other components in the valve.
The hardened inserts have a goods thickness of 6 mm and an original inside diameter (ID)
of 50 mm. They should be replaced if the inside diameter exceeds 58-60 mm.