Operating instructions

8
MAINTENANCE AND REPAIR
Mast maintenance
Inspect and lubricate mast sections at four-week intervals or every 200 operations,
whichever occurs first. If the mast has been used in a dusty environment resulting in
a build up of contaminants and old lubricant on the surface of the tubes, then this
must be removed. This can be done by wiping each section with an oil soaked cloth.
SMC build the masts using Hilomast lubricant oil (SMC Part No. 000055500). To
protect the seals oil should be injected into the spring-loaded grease fitting situated in
each collar. Alternatively, proprietary oil misters may be incorporated within the air
supply line. Sufficient oil is needed to run down the inside of each tube. During
periods of sustained cold and freezing conditions SMC/Hilomast LLC recommend the
use of Kilfrost (SMC Part No. 000055600). Periodically oil the locking collar
thumbscrew treads if fitted. Lubricant and dispensing cans are available from
SMC/Hilomast LLC. Use of oils other than those prescribed by SMC/Hilomast LLC
will invalidate the mast warranty.
FAILURE TO LUBRICATE THE MAST WILL RESULT IN DAMAGED SEALS THAT
WILL NOT BE REPLACED UNDER GUARANTEE.
Where masts are to be extended for long periods, a coating of silicone grease is
recommended to help prevent corrosion forming on the exposed metal. In dusty
conditions it may help to use silicone spray, which is almost dry in operation, on the
sections. These products are available from retail outlets.
(1) It is possible for water to enter a mast in two ways.
a) By vapour carried down the compressor line condensing in the mast. This
may be drained through the mast exhaust valve.
b) By rainwater running down the sections and collecting above the seals. This
makes a mast vulnerable to icing up. It is therefore advisable to use a mast
cover when the mast is retracted and to leave the exhaust valve open or
remove it altogether, when the mast is not in use if the conditions so dictate.
Great care should be exercised if the mast is likely to be used in freezing
conditions.
(2) Compressors should be placed on a level with or below the base of the mast to
prevent moisture build up in the airlines. If a compressor has to be placed higher
than the base of the mast, care must be taken not to allow water to become
trapped in the airlines. Disconnect the airline from the mast and blow out the line
at frequent intervals or fit a drain valve at the base level of the mast.
Hilomast Seal Replacement
If the mast will not extend due to air leakage, first check that air is not escaping from
the inlet or air release valves.
When the mast has been stored in a horizontal position, the seals may deform
slightly and allow air to pass. It is also possible under some storage conditions, for
the grease used in manufacture to harden and prevent the seal lip from touching the
tube wall.