Howden Roots 412 HPT Installation, Operation & Maintenance Manual
www.howden.com
Roots® 412 HPT Blower
Installation Operation & Maintenance Manual
ISRB-2009, Rev. 02_17.
Contents
Information Summary ...............................................................2
Safety Precautions ....................................................................3
Operating Limitations ................................................................3
Installation ........................................................................... 4 - 5
Operation......................... .........................................................6
Lubrication........................ ........................................................6
Troubleshooting ........................................................................ 8
Inspection & Maintenance ........................................................9
Parts List........................................ .........................................10
Figures..................................... ......................................... 11-14
Outline Drawing........................... ...........................................15
Do these things to get the most from your Roots Blower
• Check shipment for damage. If found, le claim with
carrier and notify Howden.
• Unpack shipment carefully, and check contents against
Packing List. Notify Howden if a shortage appears.
• Store in a clean, dry location until ready for installation.
Lift by methods discussed under INSTALLATION to
avoid straining or distorting the equipment. Keep covers
on all openings. Protect against weather and corrosion
if outdoor storage is necessary.
• Read OPERATING LIMITATIONS and INSTALLATION
sections in this manual and plan the complete
installation.
• Provide for adequate safeguards against accidents
to persons working on or near the equipment
during both installation and operation. See SAFETY
PRECAUTIONS.
• Install all equipment correctly. Foundation design
must be adequate and piping carefully done. Use
recommended accessories for operating protection.
Roots products are sold subject to the current General Terms of Sale, ES104 and Warranty Policy WP-5020.
Copies are available upon request.
• Make sure both driving and driven equipment is
correctly lubricated before start-up. See LUBRICATION.
• In event of trouble during installation or operation, do
not attempt repairs of Roots furnished equipment.
Notify Roots, giving all nameplate information plus an
outline of operating conditions and a description of the
trouble. Unauthorized attempts at equipment repair
may void Roots warranty.
• Units out of warranty may be repaired or adjusted by
the owner. Good inspection and maintenance practices
should reduce the need for repairs.
NOTE: Information in this manual is correct as of the date
of publication. Howden reserves the right to make design or
material changes without notice, and without obligation to make
similar changes on equipment of prior manufacture.
For your nearest Howden Oce, dial our Customer Service
Hot Line toll free in the U.S.; 1 877 363 7668 or
direct +1 832 590 2600.
2
ISRB-2009, Rev. 02_17.
Safety Precautions
It is important that all personnel observe safety precautions
to minimize the chances of injury. Among many
considerations, the following should be particularly noted:
• Blower casing and associated piping or accessories
may become hot enough to cause major skin burns
on contact.
• Internal and external rotating parts of the blower and
driving equipment can produce serious physical injuries.
Do not reach into any opening in the blower while it is
operating, or while subject to accidental starting.
Protect external moving parts with adequate guards.
• Disconnect power before doing any work, and avoid
bypassing or rendering inoperative any safety or
protective devices.
• If blower is operated with piping disconnected, place a
strong coarse screen over the inlet and avoid standing
in the discharge air stream.
•
CAUTION: Never cover the blower inlet with your
hand or other part of body.
• Stay clear of inlet and discharge openings.
• Stay clear of the blast from pressure relief valves and
the suction area of vacuum relief valves.
• Use proper care and good procedures in handling,
lifting, installing, operating and maintaining the
equipment.
• Casing pressure must not exceed 25 PSI (1725 mbar)
gauge. Do not pressurize vented cavities from an
external source, nor restrict the vents without rst
consulting Roots.
• Do not use air blowers on explosive or hazardous
gases.
• Other potential hazards to safety may also be
associated with operation of this equipment.
All personnel working in or passing through the area
should be trained to exercise adequate general
safety precautions.
Operating Limitations
A Howden Roots blower must be operated within certain
approved limiting conditions to enable continued satisfactory
performance. Warranty is contingent on such operation.
Maximum limits for pressure, temperature and speed are
specied in TABLE 1 for this truck application blower.
These limits apply to this blower of normal construction,
when operated under standard operating conditions.
Be sure to arrange connections or taps for instruments
used to measure temperature, pressure and vacuum at
or near the inlet and discharge connections of the blower.
These, along with tachometer will enable period checks of
operating conditions.
Pressure
The pressure rise, between inlet and discharge, must not
exceed the gure listed in TABLE 1.
• The term “intermittent operation” is dened as operation
for no longer than 10 seconds at maximum pressure list
in TABLE 1, provided that the inlet restriction (lter
pressure drop, etc.) does not exceed 20” (508 mm)
of water.
• Also, in any system where the blower inlet is at a
positive pressure above atmospheric, a maximum
case rating of 25 PSI gauge (1725 mbar) should not
be exceeded. Never should the maximum dierential
pressure be exceeded.
Temperature
Blowers are approved only for installations where following
temperature limits can be maintained in service.
• Measured temperature rise must not exceed listed
values when inlet is at ambient temperature. Ambient
temperature is considered as the general temperature
of the space around the unit. This is not outdoor
temperatures unless unit is mounted outdoors.
• If inlet temperature is higher than ambient, the listed
allowable temperature rise values must be reduced by
2/3 of the dierence between the actual measured inlet
temperature and the ambient temperature. Example:
Tinlet = 150 °F and Tambient = 60 °F; Temperature rise
limit, ∆Tnew = 350 – 2/3(150-60) = 290 °F.
• The ambient temperature of the space the blower/
motor is installed in should not be higher than
120 °F (49 °C).
Speed
This blower may be operated at speeds up to the maximum
listed in TABLE 1. Blower may be direct coupled to suitable
constant or variable speed driver if pressure/temperature
conditions are also within limits. At low speeds, excessive
temperature rise may be a limiting factor.
Special Note: The listed maximum temperature rise may
occur well before its maximum pressure is reached. This
may occur at high altitude, low vacuum or at very low
speed. The blower operating limit is always determined by
the maximum rating reached rst. It can be any one of the
three: Pressure, Temperature or Speed.
3
ISRB-2009, Rev. 02_17.
Installation
Howden Roots blowers arrive without lubrication in the sump,
see lubrication section for details.
Howden Roots blowers are treated after factory assembly to
protect against normal atmospheric corrosion. The maximum
period of protection is considered to be one year under
average conditions, if shipping plugs & seals or not removed.
Protection against chemical or salt water atmosphere is not
approved. Avoid opening unit until ready to start installation,
as corrosion protection will be quickly lost due to evaporation.
If there is to be an extended period between installation and
start-up, following steps should be taken to ensure corrosion
protection.
• Coat intervals of cylinder, gearbox and drive end bearing
reservoir with Nox-Rust VCI-10 or equivalent. Repeat
once a year or as conditions may require. Nox-Rust
VCI-10 is petroleum soluble and does not have to be
removed before lubricating. It may be obtained from
Daubert Chemical Co., 2000 Spring Rd., Oak Brook,
IL. 60521.
• Paint shaft extension, inlet & discharge anges and any
other exposed surfaces with Nox-Rust X-110 or
equivalent.
• Seal inlet, discharge and vent openings. It is not
recommended that blower be set in place, piped to the
system, and allowed to remain idle for extended periods.
If any part is left open to the atmosphere, the Nox-Rust
VCI-10 vapor will escape and lose its eectiveness.
• Protect blower from excessive vibration during storage.
• Rotate shaft three to four revolutions every two weeks.
• Prior to start up, remove ange covers on both inlet &
discharge anges and covers on vent opening and
inspect internal clearances. Also, at this time, inspect
gear box intervals thru breather location for rust.
Because of the completely enclosed blower design, location
of the installation is generally not a critical matter. A clean,
dry and protected indoor location is preferred; however, an
outdoor location will normally give satisfactory service. Important requirements are that the correct grade lubricating oil be
provided for expected operating temperatures, and that the
blower be located so that routine checking and servicing can
be performed conveniently. Proper care in locating drive and
accessory equipment must also be considered.
Supervision of the installation by a Howden Roots Service
Engineer is not usually required for these units. Workmen with
experience installing light to medium weight machinery should
be able to produce satisfactory results. Handling of
equipment needs to be accomplished with care, and in
compliance with safe practices. Unit mounting must be solid,
without strain or twist, and air piping must be clean, accurately
aligned and properly connected.
Mounting
Two methods are used to handle a unit. One is to install lifting
lugs into the (4) 5/8-11 tapped holes in top of the unit. Test the
lifting lugs for tightness and potential fractures by tapping with
hammer. In lifting, keep the direction of cable pull on these
bolts as nearly vertical as possible. If unable to use the tapped
holes in top of unit for lifting, lifting slings or a special cradle
may be passed under the unit for vertical lift.
4
ISRB-2009, Rev. 02_17.
Bottom inlet, top discharge is standard orientation with CCW
rotation on input drive shaft. Blower can be mounted either
on roadside or curbside of truck chassis. Exact installation
instructions cannot be given because of the variety of truck
chassis available. See SKETCH 1 for basic details. Units are
typically held in place on truck chassis by use of “L” shaped
mounting bracket; see SKECH #2 for basic details.
Check output speed range of PTO. It must be for the
blower range.
The blower should be parallel to the truck frame to minimize
vibration.
The PTO shaft must be within the manufacturer’s angularity
limits, not to exceed 5 degrees in the horizontal plane and
3 degrees in the vertical plane.
Brace mounting securely to reduce vibration.
Be sure air lter, oil level gauge, gear case breather and oil
drain plug is not obstructed for normal maintenance.
Do not weld on the blower or base, bearings can be damaged
by the passage of current.
Piping
Install an adequate air lter on blower inlet. Servicing the air
lters is one the most important maintenance operations.
Servicing frequency of lter elements is not time predictable
and must be by the user, depending on dust and moisture
conditions but pressure drop shall never exceed 20” (508 mm)
of water before servicing. Dry lter element life is typically 50
to 300 hours before replacement is necessary. Only replace,
do not reuse dry lter elements via cleaning. Do not allow oil,
grease or solvents to contact the element. Do not operate
blower with damaged lter seals or element. Do not operate
blower without lter element.
WARNING: All piping and accessories downstream of blower
should be rated for the internal pressures being subjected
during full operation.
Insure that inlet and discharge piping are clear, clean and
air tight. Do not allow dirt to enter the blower during piping
operations.
Pressure service, install an air relief valve in discharge line as
close to blower as possible. Vacuum service, install an air relief
valve in inlet line as close to blower as possible. Do not use
any caps, covers, plugs or valves between the blower and
relief valve.
Install a check valve in the discharge line after the relief valve
to prevent back ow of material into the blower and to prevent
reverse rotation of the blower.
Provide a discharge bypass valve to the atmosphere for air
bleed o to lower pressure when too high blower speed thus
ow is present.
Pressure service, install an accurate pressure gauge at or near
the blower discharge. Vacuum service, install an accurate
vacuum gauge at or near the blower inlet.
Install an accurate vacuum gauge or indicator at inlet so able
measure pressure drop across inlet lter.
Provide an adequate sized discharge line. Use as few of
bends as possible; when bends are necessary, use long
radius bends.
Make provisions in piping to allow for expansion as near to
the blower as possible.
Use a dust cover at the nal discharge opening when hose
is removed.
Install discharge silencer after the check valve when additional
noise reduction is required.
5
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