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Foundations and supporting structures – Twin City MPQN/MPQS Modular Plenum Fans - ES-110 User Manual

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Twin City Engineering Supplement ES-110

Storage Procedure. –. Fans. should. be. stored. indoors.

whenever. possible. where. control. over. temperature,.

shock.and.dust.is.reasonably.maintained..If.units.are.to.

be.stored.outside.in.the.elements,.they.should.be.cov-

ered. with. a. water-resistant. material.. Stored. equipment.

should. be. stored. on. a. clean,. dry. floor. or. blocked. up.

off.the.ground.on.blocks.to.prevent.unit.from.setting.in.

any.water.or.directly.on.the.ground..If.shock.or.vibration.

will.be.present.during.storage,.the.unit.may.need.to.be.

placed.on.some.type.of.vibration.dampening.material.to.

aid.in.preventing.brinelling.of.the.bearing.surfaces.

Periodic Check.–.On.a.monthly.interval,.the.equipment.

should. be. checked. to. ensure. that. it. has. remained. in.

an. acceptable. stored. condition.. The. fan. wheel. should.

be.rotated.several.times.by.hand.while.adding.enough.

grease. to. replenish. the. bearing. surfaces. with. fresh.

grease. and. to. maintain. a. full. bearing. cavity.. Grease.

used.must.be.compatible.with.that.already.supplied.in.

the. motor. and. fan. bearings.. The. fan. impeller. should.

be. left. at. approximately. 180. degrees. from. that. of. the.

previous.month.to.prevent.the.shaft.and.impeller.from.

taking. a. set. in. one. position.. Storage. records. should.

be. maintained. which. indicate. the. above. requirements.

have.been.followed..Consult.the.motor.manufacturer.for.

proper.storage,.space.heater.connection.and.lubrication.

if.the.unit.was.supplied.with.one.

Start-Up.–.When.the.unit.is.removed.from.storage,.all.

bearing.grease.should.be.purged.and.replenished.with.

fresh. grease. as. per. the. lubrication. decal.. The. motor.

should.be.measured.to.verify.that.the.resistance.is.still.

at.a.satisfactory.level.compared.to.the.value.recorded.

prior.to.storage.

Foundations and Supporting Structures

Floor.mounted.fans.should.be.installed.on.a.flat,.level.

surface. with. sufficient. structure. support.. Support. shall.

be.suitable.for.static.and.dynamic.loads.and.foundation.

frequencies. be. separated. at. least. 20%. from. the. rota-

tional.speed/speed.ranges.

. If.the.fans.are.mounted.on.a.sub-structure,.an.inertia.

base.with.spring.isolator.system.should.be.considered.

. Fans. mounted. to. or. within. a. structure. should. be.

placed. as. close. as. possible. to. a. rigid. member. such.

as. a. wall. or. column.. The. structure. must. be. designed.

for. rotating. equipment;. static. design. for. strength. is.

not. sufficient. to. insure. proper. operation.. Supports. for.

suspended. fans. must. be. cross-braced. to. prevent. side.

sway..Structural.resonance.should.be.at.least.20%.from.

fan.operating.speed.

. Any.ducting.and/or.dampers.with.sleeves.should.have.

independent. support;. do. not. use. the. fan. for. support..

Isolating. the. fan. from. ductwork. with. flex. connections.

eliminates.transmission.of.vibration.
1..Sufficient. structure. must. be. provided. to. support.

weight.of.fan.assembly.

2..Sufficient. restraint. must. be. provided. to. resist. the.

pressure. force. against. the. fans.. Typically. fans. are.

assembled.in.an.application.in.a.modular.fashion.with.

multiple.fans.working.in.parallel..The.cumulative.thrust.

force.must.be.restrained.to.prevent.the.fan.assemblies.

from.leaning.or.tipping.forward..The.force.acting.on.

the.fan.assemblies.is.calculated.as.shown.below.

. Thrust.force.(lb

f

).=.H.x.W.x.N.x.P

s

.

27.68

. Where
. P

s

..=.Maximum.operating.static.pressure.(in..w.g.)

. W..=.Width.of.each.individual.fan.(in.)
. H. =.Height.of.each.individual.fan.(in.)
. N. =.Quantity.of.fans.in.system
. 27.68.=.conversion.factor.for.in..w.g..to.PSI

. Example
. Parallel.fan.system.employing.nine.(9).–.Size.182.fans.

in.a.3.x.3.configuration..(3.fans.high.x.3.fans.wide)

. System.pressure.is.5.inches.of.water.column.
. Outside.dimension.of.fan.housing.=.approx..32.in..by.

32.in.

. Thrust.force.(lb

f

).=.H.x.W.x.N.x.P

s

.

27.68

. Thrust.force.(lb

f

).=.32.x.32.x.9.x.5.=.1665.(lb

f

)

.

27.68

.

Note:.The.thrust.force.is.distributed.evenly.across.the.front.
surface.of.the.parallel.fan.system.

3..Recommend.attachments.to.the.sides.and.top.of.the.

parallel.fan.system.incorporating.some.form.of.spring.

support,.i.e..rubber.snubbers/isolators.or.springs..Such.

devices.should.be.attached.to.prevent.significant.point.

loading.on.an.individual.fan..They.should.be.located.

on.the.side.of.the.parallel.fan.system.at.the.top.cor-

ner.and.along.the.top.every.2.fans.or.less.

a..When.the.fans.are.rigidly.mounted.to.the.base,.an.

assumption. can. be. made. that. half. of. the. thrust.

load.will.be.supported.at.the.base,.and.the.sup-

ports.added.at.the.top.of.the.fan.need.to.carry.a.

minimum.of.one.half.of.the.thrust.load.

b..When.the.fans.are.supported.on.an.isolation.base.

or. isolators,. it. will. be. necessary. to. add. thrust.

restraints.around.the.periphery.of.the.fan.assembly.

to. support. the. entire. thrust. load.. Flex. connec-

tions.are.required.when.using.isolators.or.isolation.

base.

c..Attachments.to.the.fan.can.be.made.utilizing.the.

factory.mounting.holes..Recommend.that.the.gage.

of.the.materials.be.checked.for.tear.out.strength.

in. thrust. applications.. If. necessary. utilize. multiple.

mounting.hole.locations.to.distribute.the.load.