Twin City Centrifugal Fans - ES-52 - Manual (Page 8)

Bearing Problems:
Generally. speaking,. Twin.City. Fan. &.Blower. uses. three.
types.of.bearings:
1..Ball.bearing.with.set.screw.lock.
2..Spherical.roller.bearings.with.set.screw.lock.
3..Spherical.roller.bearings.with.adapter.lock/taper.lock.
feature.to.attach.them.to.the.shaft.
Ball bearings. –. These. are. self-aligning. bearings. and.
should.present.no.alignment.problems.with.one.excep-
tion:.i.e.,.on.Sealmaster.bearings.there.is.a.pin.beneath.
the.grease.fitting.which.prevents.the.bearings.outer.race.
from.rotating..Should.this.pin.jam,.the.bearing.loses.its.
alignment.feature.
. Common.failure.causes.are.(1).set.screws.loosening.
and. shaft. turning. within. the. bearing,. and. (2). crowned.
bearing. supports.. Loosen. one. bolt. and. measure. the.
clearance. between. the. pillow. block. and. the. support..
Add.shim.to.compensate..
Spherical Roller Bearings with Set Screw Lock. –. The.
self-aligning.characteristic.of.these.bearings.are.inherent.
in.the.spherical.roller.design..The.closer.that.these.bear-
ings.are.to.perfect.alignment,.the.cooler.they.will.operate.
. Common. failure. causes. are. the. same. as. with. ball.
bearings,. mainly. set. screws. loosening. and. crowned.
bearing.supports..
Spherical Roller Bearings with Adapter Lock. –. Again,.
the. self-aligning. feature. is. inherent. in. the. spherical.
design.. Good. alignment. results. in. a. cooler. operating.
bearing..The.faster.the.bearing.operates.the.more.criti-
cal.this.becomes.
. A. common. cause. of. failure. is. improper. installation.
practice..Removing.too.much.clearance.from.the.bearing.
can.result.in.preloading.the.bearing,.resulting.in.prema-
ture.failure;.and.removing.not.enough.can.result.in.the.
shaft.rotating.within.the.bearing..Properly.tightened,.this.
method.of.attaching.a.bearing.to.a.shaft.is.second.only.
to.a.press.fit..Crowned.bearing.supports.can.also.pre-
load.these.bearings.and.should.be.checked.by.loosening.
one.side.of.the.bearing.and.checking.for.clearance.
Lubrication. –. The. major. cause. of. bearing. failure. is.
contamination.of.grease,.insufficient.grease,.or.incompat-
ibility.of.grease..If.a.fan.is.to.be.stored.for.any.length.
of.time.at.the.job.site,.the.bearings.immediately.should.
be. filled. with. grease. while. rotating. the. shaft. and. then.
the.bearings.should.be.regreased.and.rotated.monthly..
This.will.prevent.moisture,.which.condenses.within.the.
bearing,. from. corroding. the. raceways.. Most. greases.
used. on. fan. pillow. blocks. are. lithium. base.. Use. the.
greases. shown. on. the. bearing. decal.. Do. not. mix. the.
bases.without.completely.purging.out.the.initial.grease.
. Initially,.follow.the.lubrication.instruction.on.the.side.
of. the. fan.. The. frequency. of. lubrication. should. be.
adjusted.depending.on.the.condition.of.the.old.grease.
being. purged.. This. is. the. responsibility. of. the. user.. If.
the.grease.is.dirty,.the.lubrication.frequency.should.be.
more.often.
a..Noise. –. If. a. bearing. is. increasing. in. noise. intensity.
and/or.vibration,.it.will.probably.result.in.failure.
b..Temperature. –. If. a. bearing. temperature. begins. to.
gradually. rise,. it. will. generally. result. in. failure.. A.
bearing.can.operate.up.to.200.degrees.and.operate.
satisfactorily.if.the.temperature.remains.constant.and.
the.bearing.receives.adequate.lubrication..Remember.
that.a.roller.bearing.under.the.same.load.and.speed.
will.be.somewhat.more.noisy.and.run.warmer.than.a.
ball.bearing..This.is.normal.
Rough.handling.and/or.dropping.a.fan.can.result.in.bri-
nelling.the.bearing..This.appears.as.a.clicking.noise.at.
first,.then.gradually.worsens.until.failure.
. When.replacing.a.bearing,.always.align.the.bearings.
first,.then.bolt.the.pillow.blocks.to.their.support,.rotate.
the. shaft,. fasten. the. bearings. to. it.. If. the. bearing. is.
fastened. to. the. shaft. first,. tightening. the. pillow. block.
bolts.may.bind.the.shaft.and.preload.the.bearings.
Limitation of Warranties and Claims
Seller.warrants.to.the.original.purchaser.that.the.goods.
sold.hereunder.shall.be.free.from.defects.in.workman-
ship.and.material.under.normal.use.and.service.(except.
in.those.cases.where.the.materials.are.supplied.by.the.
buyer).for.a.period.of.one.year.from.the.date.of.original.
installation. or. eighteen. (18). months. from. the. date. of.
shipment,. whichever. occurs. first.. The. liability. of. seller.
under.this.warranty.is.limited.to.replacing,.repairing,.or.
issuing. credit. (at. cost,. F.O.B.. factory. and. at. seller’s.
discretion).for.any.part.or.parts.which.are.returned.by.
buyer.during.such.period.provided.that:
a.. seller.is.notified.in.writing.within.ten.(10).days.fol-
lowing.discovery.of.such.defects.by.buyer,.or.within.
ten.(10).days.after.such.defects.should.reasonably.
have.been.discovered,.whichever.is.less;
b.. the.defective.unit.is.returned.to.seller,.transportation.
charges.prepaid.by.buyer.
c.. payment.in.full.has.been.received.by.seller.or.said.
products;.and
d.. seller’s.examination.of.such.unit.shall.disclose.to.its.
satisfaction.that.such.defects.have.not.been.caused.
by. misuse,. neglect,. improper. installation,. repair,.
alteration,.act.of.God,.or.accident.
e.. seller. cannot. guarantee. sound. pressure. levels. or.
dBA.
No.warranty.made.hereunder.shall.extend.to.any.seller.
product. whose. serial. number. is. altered,. effaced. or.
removed..Seller.makes.no.warranty,.express.or.implied,.
with. respect. to. motors,. switches,. controls,. or. other.
components.of.seller’s.product,.where.such.components.
are. warranted. separately. by. their. respective. manufac-
turers.. THIS. WARRANTY. IS. EXPRESSLY. IN. LIEU. OF.
ALL. OTHER. WARRANTIES,. EXPRESS. OR. IMPLIED,.
WHETHER. STATUTORY. OR. OTHERWISE,. INCLUDING.
ANY. IMPLIED. WARRANTY. OF. MERCHANTABILITY. OR.
FITNESS. FOR. A. PARTICULAR. PURPOSE.. In. no. event.
shall. seller. be. liable. to. buyer. for. indirect,. inciden-
tal. collateral,. or. consequential. damages. of. any. kind..
(BUYER’S.FAILURE.TO.PAY.THE.FULL.AMOUNT.DUE.
WITHIN.SIXTY.(60).DAYS.OF.DATE.OF.INVOICE.SHALL.
OPERATE.TO.RELEASE.SELLER.FROM.ANY.AND.ALL.
LIABILITY. OR. OBLIGATION. ARISING. PURSUANT. TO.
ANY. WARRANTY,. EXPRESS. OR. IMPLIED,. WHETHER.
STATUTORY.OR.OTHERWISE,.INCLUDING.ANY.IMPLIED.
WARRANTY.OR.MERCHANTABILITY.OR.FITNESS.FOR.
A. PARTICULAR. PURPOSE,. MADE. IN. CONNECTION.
WITH.ANY.CONTRACT.FORMED.HEREUNDER..BUYER.
AGREES. THAT. SUCH. FAILURE. TO. PAY. SHALL.
CONSTITUTE.A.VOLUNTARY.WAIVER.OF.ANY.AND.ALL.
SUCH. WARRANTIES. ARISING. PURSUANT. TO. SUCH.
CONTACT.)
15MWG06/14
TWIN CITY FAN & BLOWER | WWW.TCF.COM
5959 Trenton Lane N | Minneapolis, MN 55442 | Phone: 763-551-7600 | Fax: 763-551-7601