Depa DH50-FA - Page 34

34
DEPA
®
Air Operated Diaphragm Pumps
Fault Possible cause Remedy
Pump does not work despite
air supply
Valveballsdeformed
Pump leaking at the clamp
band
PTFE diaphragm cracked a
after short time
Insucientsuctionhead
Pump very loud, crackling
noise
Piston rod hard moving
Muerclogged
Airinletlterclogged
Valveballsstickingto
valve seat
Chemical attack
Mechanical attack
Clamp band cracked
Diaphragm not centred
during assembly
Large solids in product
Compressed air opened with a shock
Valveballandseatleaking
Pump completely dry
Control valve worn
Excessivefeedonthe
suction side
Compressed air too dry
(Instrument air)
Temperature too high
Compressed air dirty
Piston rod run in
Clean or renew
Clean or renew
Loosen, use PTFE balls
instead
Change material
Change material
Replace
Assemble again
Installalter
Install a slow start valve
Replace
Fill suction line
Replace
Install heavier valve balls
Throttling of suction line
Lubricate the air
Cool down
Installalter
Replace