轴承负荷测量中负荷传感器的研究
第15卷
2001年3月
山东工程学院学报
JournalofShandonghtsfituteofToehnology
V0l15No
l
Mar/200I
Study
on
theLoadCellforBearingLoad
Measurement
cbng疡昭
(Shandong
Wang
Shujun
255012,China)
InstituteofTeclmology,Zibo
TaoZhaohu/
(AdministrationConmfittee0fzib0DevelopmentZone,Zibo255086.ckIla)
Abstract
Ashearbeamtyperesistance
a
stl曲rl
gaugeloadcellwhich
vail
beinfixedinthebea^ngwasdeveloped
forthepurposeofmeasuringtheloadin
4一padtildng—padbearingusedinlargescaleturbo—generatorsets.The
designing
lionwelle
principle,criteriaandmechanicalmodelwereoudinedanddiscussed.Theresultsgiven.Theloadcell,’8technicalparameters
were
hWl
theoreticalcalcula—
alsodetermined.
Keywords
loadcell,hrgescaleturbo—generatorsets,tilting—Padbeating,straingage,measurement
Thestaticanddynamicloadsinkindsof
tion
on
a
rotorsystemoflarge—scaleturbo-generatorsets
ORe
are
homebyabout10different
bearings,The4一pad
on
tilting
padbef耐ngis
oftheminhomebred300MWand600M'Wsets.The
distribu—
ofloadthese
bea血gaisaffectedbymanyfactorsand
varieswi吐lthechangesofthesefactors.Changesofloads
a
severe
bearingswillaltermanypropertiesincludingstaticanddynamiccharacteristicsofthebeatings,andhave
effectonthereliabilityandsafetyoftherotor—bearingsystem.Sometimestheymayresultinaccidents.suchastheoil
filmwhirl.At
present.the咖dvofon-linemonitoringtheeORdifi叽ofbeatingshasdrawnnK靴attendOR.An,,0|ag
is
the
methodsofmeasuringbeatingloadsinlaI铲tI】I量m—generatorsets,thedirectforcesuitableforon—linemonitoring,whichdirectlyforceflowpathsinthehthispaper.
l'nefl,Sul'e5
measu面19(DFM)method
11101t
theloadswithloadcellsfixedinsuitablepositionsinthe
be删ng.Thekeyofthemethodistheconstructiondnsignoftheloadcell.Astu由iscarried
out
11
TheprincipleoftheloadcellAloadcellisclassifiedas
a
force
transducer.Thisdevicecenvertsforceinto
an
electrical
sisml.There
are
two
metalcomponentsinload.thegaugesof
a
a
loadcell,theflexure(sp面ngdement)andthestraingauge(sensor),theflexurebearthe
minuledeflection.Eachgaugepatchconsistsof
strain
or
serxseoneoriiioiE
finewiescementedtothesurface
to
beam,ring,or
column(theelement)within
a
loadcell.AsthesurfacewhichthegaugeisatIachedbe・theappliedload.Aloadcell
a
COI/KjS
es
strained,thewiresstretch
or
compresschangingtheirresistancepmportianal
create
tO
US—
onemorestrain
gauges.Multiplestraingaugesa坤connectedto
isapplied
to
thefourlegsof
a
Wheatstone—bridge
tO
con—
figuration.When∞inputvoltage
cell
thebridge.theoutputbecomes
voltageproportional
theforce
on
the
ThisoutputCanbeamplifiedandprocessedbysignalconditioners.
收文日期:2001—03—5
作者简介:丛红.(1969一).女(汉族),山东威海市人,山东工程学院机械学院讲师.主要从事传感器及智能化检测与控制方嘶的研究。
万方数据
第1期
丛红等:轴承负荷测量中负荷传感器的研究
1.2
Basic
aesi鲫criteria
Thebasicdesigncriteriaoftheloadceilapplied
to
tilting-padbeaTiTlg021_e:
(a)Construction
adaptebility--The
size,installationandfixationoftheload
cellshouldad印t
to
theconstruction
requirementsofthe
beating,The
construction
ofthebeatingshouldbebasicallyunchanged.
(b)Functionadaptability---Thefunctionandothertechnicalrequlre,mentsofthebearingshould
not
beaffectedby
the
infixingofloadceils.Forexample.dlesbfinassofthecellshouldbemuchgreaterthanthatoftheoilfilmofthe
tested
hearing,generally
greater
than108N/m.
(C)Environmentadaptability--ThehaIlsducershouldadapt
to
theworkenvirorarmntofthe
bearing.such
astern—
peratuve.humidityand
sealing
requirement.especiallyagainst
lubricating
oil
e£c,
(d)Rehabilitr—ThefailureoftheLr}LrlsducelSshouldnot
resultinmalfunctionofthe
sets.
(e)Long—termstability--Theratioof
output
andinputof
the删ucer
bearing
shouldkeep
constant
for
a
longperiod
oftime.
2
ConsO'uctionanalysis
2.1
Constructionreqtfirenmat
Forthe4一padtilting—padbeating,as
showninFig.1,theloadcells
can
beinstalledandf=ed
on
the4sup—
poamgpivotsofthepadsrespectively,and
Call
bedesigned
into
supportingpads
as
part
ofthe
bearingsets.’11Ieapplied
force
on
thebearingisabout25KN.whichc∞bemeasured
bvtheelasticdeformationofthe
sensingdement.弧e口凼al
shiftofthetilting—padmustbelessthanO.01nma,thatistosay.theiTkqiimllIIldeflectionoftheloadcellis0.01rma.
Consideringthemanufacturing,installing
andsealing
techndngiesandspacelimitation,theoptimalconstluetionis
Fig.1Construction0f
a
4一paddKng—paabeating
determined(Fig.2).
1一beariIlg
horⅨe卜mt吨一pad
3,4,5一pivot
6一蛐
2.2
MechanicalmodelThe
loadcell
ismadeof
a
blockofmetal一40Ctand
manufacturedbywirecutting.Itcall
beregarded
astwo
shearbeamswith
I一州CYOSS
sectionandfⅨedends.In
thedirectionswhichforman.ngleof4500r135。withthe
center
linesofthe
k∞’sidefaces,the
tensileandcom—
pressive
stress
GO/UL%to
maximumvaluewhilethe
bending
moments
ale
equal
to
zero.Thedistributionof
shearing
fore—
es
andbendingmomentsare
showninFig.3,WhenF
acts
at
themiddlepoint,theprincipalsnailland
BⅡess
inthe
45。directionintheneutralhyerCanbewritten
3,(1+“)
B日2一Bh。+bh。
‘一4bE
BH3一肌3+6矿
匪
吼2
r再
&
.
啦2—丌i
whereBisthewidthofthebeam,H
is龇hei曲t
ofthebeam,his出e
heigllt
ofthebeam’Sweb,bisthewidthof
thebeam’Sweb,Eistheelasticmodulusof40cr,pisPois帅nratio.
.111eItmxinnlmbending
Btress
Canbecomputedfrmlthefollowing
equation:
4—2玎丽『=五万丽
3FLH
万
方数据
一30一
山东工程学院学报
thefollowingequation
2001年
whereListhelengthofthebeam.Forthedenecd∞ofthebeam,we
,
厶。—2E(BH3-—Bh3+bh3)
儿。
A
USe
i-[3
A—A
8一B
嬲引
77T/'/Z
//////Z////髟).w。。,/】
厅
ng.2
Sckm娟cdiagram0ftheshearbeamloadcell
When
aset
ofDa珀皿ete璐isselected
fits
follows:B=
厂
18ram,H=12ram,h=8nun,b=8mm,the
p血cipal
strain
(£),山e
bending
call
analyticalequivalent
stre88(d3d),tIlem邮出咖∞
s峨(d一)andstrain(e一),thedeflection(f8)
x
beobtained:£≈1320×10一,d3d4419.22Mpa,o。。一
162.73Mpa<口3d,£~≈790.72×10—6<E,^≈1.39
10。Film<0.01ram,SOequivalent
stIeSs
懈
F,2
the
principal
are
8t11lin
mad蛐alyIical
maximumin
wherethegauges
nIeet
pasted
are
theelasticelementand2.3
thedesignrequirmnent.
FL,
Qdcm砒I矗g
When
a
result宜帆FEMamly菇s
to
forceFisappliedinthesym'netricalplaneofthe
halfofthebeamnq8Is
beconsidered.The
beam.only
one
shearbeamisdividedinto98unitsand1320nodswhen
units
ter
Iriangle
a
8madopted.Theresrdtsshowni11Table1presents
to
bet—
agIeeInent
thedesigned
one
whoseFEM¥lxsinvalueis
betweenthatoftheanalogyanalysisand
IMM㈣t
Table1
Remitsfrom
tmslagy,删砌d群而m吐
Analogy1320.2
FEMI153.3
M∞m
脚dII・m
1226
M“kmⅡdxain(Ij£)
万方数据
第1期丛红等:轴承负荷澳I量中负荷传感器的研究
31—
3
Performanceandteelmieallmrameters
Oncetheloadcellismanufactured,thegauges
are
mounted
to
thestrainelementwithspeciallyformulatedadhe—
slves(No.610).The
precise
positioningofthegauge,themountingprocedure,andthematerialsusedallhave
a
measurableeffect
on
overallperformanceoftheloadcell.抽orderto
achievetempemtureinsensitiveoutput,tempera—
ture
sensitiveresisterswhich
are
inthermal
contact
withtheloadcellare
appliedinthebridgecircuitforcompensati—
011.Themajor
technicalparametersofloadcell
are
showninTable2.
Table2
Majortedmicallmrmnetexs
oftheload
call(Calataty:30KN)
4Conclusion
The
constructionoftheshearbeamandtheparanletersdesignedan
reasonable.The
resultsfromanalysisand
ex-
pezlmentshowthattheloadcellirlc℃tthe
design
requirementsandbeagpliedfortheloadmeasllle—mentofthe4
一pad
tilting—pad
k啦in
OAthlargeturbo—generatorsets.
Refelmaets
11]黄继昌・传感器工作原理及应用实例-北京:人民邮电出版社。199812]单成祥・传感器的理论与设计基础及其应用・北京:国防工业出版社,1999L3]SMnin,M.M.,Uehiyama
M.AnalyaealModelsfor
Desi鲥ngForceSencorsProceedingsofthe1994皿EEInternationalCoIIfcl3BIlCe
∞RoboticsandAutomnationSanDiego。cA,US.A.1994
[4]c0IlgHong。AResearch
oaltheDesign
andApplicationofSensorsintheCon础onM耐m[iIlg口fHydrodynamic
LubricatingBearings
Xi’anJiaotong
Univelsity,Xi’∞,1996
轴承负荷测量中负荷传感器的研究
丛红
王淑君
山东工程学院,山东淄博255012
陶朝晖
淄博市开发区管委会,山东淄博255086
摘要本文设计了一种可嵌入轴承内部的电阻应变式负荷传感器,以进行大型汽轮发电机组中四瓦可倾瓦轴承所受负荷的测量。该传感器为剪切梁式,本文对其原理、设计准则和力学模型进行了分析和讨论,给出了理论计算结果,并通过试验测得的主要技术¥qtt进.--步论证了结构设计的正确性。
关键词负荷传感器,大型汽轮发电机组,可倾瓦轴承,电阻应变片,测量中图分类号:TP212
文献标识码m
万
方数据