Howden Roots 2500 Series WHISPAIR MAX, Инструкция по установке, эксплуатации и обслуживанию

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ISRB
2005 GEA 20260
Page 13 of 24
confined to the bearings (which support and locate
the shafts) the oil seals, and the timing gears. All are
lubricated and wear should be minimal if clean oil of
the correct grade is always used. Seals are subject to
deterioration and wear, and may require replacement
at varying periods.
Shaft bearings are designed for optimum life under
average conditions with proper lubrication and are
critical to the service life of the blower. Gradual
bearing wear may allow a shaft position to change
slightly, until rubbing develops between impeller and
casing. This will cause spot heating, which can be
detected by observing these surfaces. Sudden
bearing situations is usually more serious. Since the
shaft and impeller are no longer supported and
properly located, extensive general damage to the
blower casing and gears is likely to occur.
Oil seals should be considered expendable items, to
be replaced whenever drainage from the headplate
vent cavity becomes excessive or when the blower is
disassembled for any reason. Some oil seal weepage
may occur since an oil film under the lip is required
for proper operation. Periodically leaked oil should be
wiped off from surfaces. Minor seal weepage should
not be considered as indicating seal replacement.
Timing gear wear, when correct lubrication is
maintained, should be negligible. Gear teeth are cut
to provide the correct amount of backlash, and gears
correctly mounted on the shafts will accommodate a
normal amount of tooth wear without permitting
contact between lobes of the two impellers. However,
too high an oil level will cause churning and
excessive heating. This is indicated by unusually high
temperature at the bottom of the gear housing.
Consequent heating of the gears will result in loss of
tooth-clearance, backlash and rapid wear of the gear
teeth usually will develop. Continuation of this tooth
wear will eventually produce impeller contacts
(knocking), and from this point serious damage will
be unavoidable if blower operation is continued. A
similar situation can be produced suddenly by gear
tooth fracture, which is usually brought on by
sustained overloading or momentary shock loads.
Problems may also develop from causes other than
internal parts damage. Operating clearances within a
blower are only a few thousandths of an inch. This
makes it possible for impeller interferences or casing
rubs to result from shifts in the blower mounting, or
from changes in piping support. If this type of trouble
is experienced, and the blower is found to be clean,
try removing mounting strains. Loosen blower
mounting bolts and reset the leveling and drive
alignment. Then tighten mounting again, and make
sure that all piping meets blower connections
accurately and squarely. Foreign materials sucked
into the blower will also cause trouble, which can only
be cured by disconnecting the piping and thoroughly
cleaning the blower interior.
A wide range of causes & solutions for operating
troubles are covered in the TROUBLESHOOTING
CHECKLIST. The remedies suggested should be
performed by qualified mechanics with a good
background. Major repairs generally are to be
considered beyond the scope of maintenance, and
should be referred to your local Roots blower
distributor.
Warranty situations should not be repaired at all,
unless specific approval has been obtained through a
Sales Office or the factory before starting work.
Unauthorized disassembly within the warranty period
may void the warranty.
ISRB 2005 GEA 20260.indd 13 17/09/2015 12:53