Page 3 of 8PF20R-X-B
GENERAL DESCRIPTION
TheARO diaphragm pump offers high volume delivery even at low air
pressureand a broad range of material compatibility options available.
Referto the model and option chart. ARO pumps feature stall resistant
design,modular air motor / fluid sections.
Airoperated double diaphragm pumps utilize a pressure differential in
theair chambers to alternately create suction and positive fluid pressure
inthe fluid chambers, flap checks insure a positive flow of fluid.
Pumpcycling will begin as air pressure is applied and it will continue to
pumpand keep up with the demand. It will build and maintain line pres-
sureand will stop cycling once maximum line pressure is reached (dis-
pensingdevice closed) and will resume pumping as needed.
AIR AND LUBE REQUIREMENTS
WARNING EXCESSIVEAIR PRESSURE. Can cause pump
damage,personal injury or property damage.
SAfilter capable of filtering out particles larger than 50 microns should
beused on the air supply.There is no lubrication required other than
the“O” ring lubricant which is applied during assembly or repair.
SIflubricated air is present, make sure that it iscompatible with the
Nitrile“O” rings in the air motor section of the pump.
OPERATINGI NSTRUCTIONS
SAlwaysflush the pump with a solvent compatible with the material
beingpumped if the material being pumped is subject to “setting up”
whennot in use for a period of time.
SDisconnectthe air supply from the pump if it is to be inactive for a few
hours.
STheoutlet material volume is governed not only by the air supply but
alsoby the material supply available at the inlet. The material supply
tubingshould not be too small or restrictive. Be sure not to use hose
whichmight collapse.
SWhenthe diaphragm pump is used in a forced-feed (flooded inlet)
situation,it is recommended that a “Check Valve” be installed at the
airinlet.
SSecure the diaphragm pump legs to a suitable surface to insure
againstdamage by vibration.
PARTSAND SERVICE KITS
Referto the part views and descriptions as provided on page 4 through 7
forparts identification and Service Kit information.
SCertainARO “Smart Parts” are indicated which should be available
forfast repair and reduction of down time.
SService kits are divided toservice two separate diaphragm pump
functions:1.AIRSECTION,2.FLUIDSECTION.TheFLUIDSEC-
TIONis divided further to match typical part MATERIAL OPTIONS.
MAINTENANCE
SProvide a clean work surface to protect sensitive internal moving
partsfrom contamination from dirt and foreign matter during service
disassemblyand reassembly.
SKeepgood records of service activity and include pump in preven-
tivemaintenance program.
SBeforedisassembling, empty captured material in the outlet man-
ifold by turning the pump upside down to drain material from the
pump.
FLUID SECTION DISASSEMBLY
1. Remove(61) top manifold, (60) bottom manifold and (53) manifold
elbow.
2. Removethe flap valve cartridge / seat assemblies.
3. Remove(15) fluid caps.
NOTE:Only PTFE diaphragm models use a primary diaphragm (7) and
abackup diaphragm (8). Refer to the auxiliary view in the Fluid Section
illustration.
4. Removethe (6) diaphragm washer, (7) diaphragm and (5) backup
washer.
NOTE:Do not scratch or mar the surface of (1) diaphragm rod.
FLUID SECTION REASSEMBLY
SReassemblein reverse order. Refer to the torque requirements on
page5.
SClean and inspect all parts. Replace worn or damaged partswith
newparts as required.
SLubricate (1) diaphragm rod and (144) “U” cup with LubriplateR
FML-2grease (94276 grease packet is included in service kit).
SFormodels with PTFE diaphragms: Item (8) Santoprene diaphragm
isinstalled with the side marked “AIR SIDE” towards the pump cen-
ter body. Install the PTFE diaphragm (7) with the side marked
“FLUIDSIDE” towards the (15) fluid cap.
SRe-checktorque settings after pump has been re-started and run a
while.
VitonRistrademark of the DuPont Company, SKynarRis a registered trademark of Penwalt Corp.
SantopreneRisa registered trademarkof Monsanto Company, licensed to Advanced Elastomer Systems, L.P. SLubriplateRis a registered trademark of Lubriplate Division (Fiske Brothers)