5Common Faultsand Trouble-shootingMethod
Generally,thefaultsofairlesssprayercan bedividedintotwotypes:faultsinairsystemandfaultsin
coatingsystem.Ifafaultoccurs,it'sprohibitedtodismantleblindly.Thefaultshouldbeanalyzedand
eliminated step bystepasshowninthefollowingtable.Beforethat,thepressureswitchshouldbe
dismantledand theairintakeballvalveshouldbeclosed.
SN Phenomenon Reason Trouble-shooting Method
1 Notenoughpower
forreversing,small
flowduring
operation.
Airintakeamountnot enough. 1)Check ifthe pressureofairsourcemeetsthe
requirement?
0.6～0.8MPa）
2)Dothespecificationsofaircompressorandthe
drift diameterofairsourcepipelinemeetthe
requirements?(the deliverycapacityshouldnotbe
lessthan1.2m
3
/min,thedriftdiameterofthe
pipelineshouldnot belessthan20mm)
3)Aretheconnectorsoneachpipelinetightened?
4)Hastheairintakeswitchreachedthemaximum
opening?
2 Thesprayeris
whirring;the
coatingpressureis
notenough;the
atomization isnot
good.
1)Severeabrasionbetweenslide
boards;thecontactsurfaces
arenotparallel;thesealingis
not good;airpartiallyescapes;
airintakeamountofthe
cylinderdecreases;not
enough sprayingpressuredue
tothe reductionofpiston
thrust.
2)Deformationofslideblockafter
having beenusedforalong
term.Theairflowcan not
press oneslideblock onto
another,causingleakage.
3)TheO-shaperubbersealing
ringinthecylinderisabraded
andraised,resultinginan
insufficient airpressure.
4)Theairintakecartridgeis
blockedbyforeignobjects.The
airpathisnotsmooth,resulting
ininsufficientairintake
1)Dismantletheair-distributingblock andtheslide
blockandputthemonapieceofmetallographic
abrasivepaper,whichhasbeenspreadoutona
flatplate.Pushand grind themsmoothlywithboth
handsandthen cleanthem.Theflatnesscan be
checkedwithred lead powder.The even
distribution ofredsqueegeeoilonbothcontact
surfacesmeansthattheyareflat.Ifnot,grind
themagainwiththeabove-saidmethod.After
being grinded toflat,the slide boardand the
intra-cavityofthe slide blockmustbeoiledwith
20# engine oil,andassembled aspertheir
originalforms.
2)Dismantletheair-distributingblock andtheslide
block,andgrind themwithapieceofabrasive
paperuntiltheyareworkingsmoothlywiththe
reversingpiston.Oilthecavityoftheslide block
withclean20# engineoil.
3)Unscrewalltheboltsconnecting the uppercover
andthelowercovertothecylinder.Openthe
cylinder,replacethedamagedO-shape sealing
ring,andoiltheinwall ofthecylinderwithclean
20#engineoil.
4)Cleanorreplacetheairintakecartridge.
3 Thesprayerstops
afterstarting.Aair
streamsprays
continuouslyfrom
upperorlower
observationplug
hole.
Foreignobjectexistson theouter
edgeoftheO-shapesealingring
onthe reversingpiston;blowby
happensbetweentheupperand
thelowercavity.
Dismantletheair-distributingboardandtheupper
coverofthe reversing piston,takeout the reversing
piston andreplacethebrokenO-shape sealing ring.
Purgeandcleanthereversingpiston holewith
compressedair.Oiltheinwall andtheO-shape
sealing ringwithclean20# engineoilandassemble
themaspertheiroriginalforms
4Thesprayerstops
afterstarting.Aair
streamsprays
continuouslyfrom
the silencer.
1)Thereversingblock stopsat
thedead pointpositioninthe
middle.
2)TheO-shapesealingringof
thecylinderpiston isbroken.
3)TheM8nutofthe
air-distributingpiston rodis
lost.
1)Dismantlethescrewontheairintakecoverand
pushthe reversing piston tomakeitleavethe
deadpoint position.
2)Replacethe O-shapesealingringofthecylinder,
andoiltheinwall ofthecylinderwithclean20#
engineoil.
3)Re-tightentheM8nut.
5 Thepressuredrops
suddenlyduring
spraying;the
atomization isnot
good;thecoating
sprayslikeraysor
nocoatingsprays,
buttheair-driven
pumpworks
normally.
1)Thecoatingsuctioninletis
blocked.
2)Oneachvalveport, foreign
objectsraisethevalvepug.
3)Thespringabovetheplunger
valvebodyisfractured.
4) Cavitation Erosion”happens
oneachhigh-pressurevalve
port.
5)TheV-shape sealingringon
theplungervalvebodyhas
beenabraded.
1)Cleanthesuctioninlet.
2)Cleantheforeignobjectson eachvalveport.
Cleanthestrainerinside thepressurereservoir.
3)Replacethe spring.
4)Replacethesuctionvalvebody,theplunger
valvebody,the discharge valvebodyorthesteel
ball.
5)Replacethe V-shape sealing ring onthe plunger
valvebody.
