Page 4 of 12
PM20X-X-X-BXX (en)
PARTS AND SERVICE KITS
Refer to the part views and descriptions as provided on page
5 through 8 for parts identification and Service Kit informa-
tion.
y
Certain ARO “Smart Parts” are indicated which should be
available for fast repair and reduction of down time.
y
Service kits are divided to service two separate dia-
phragm pump functions: 1. AIR SECTION, 2. FLUID SEC-
TION. The FLUID SECTION is divided further to match
typical part MATERIAL OPTIONS.
MAINTENANCE
y
Provide a clean work surface to protect sensitive internal
moving parts from contamination from dirt and foreign-
matter during service disassembly and reassembly.
y
Keep good records of service activity and include pump
in preventive maintenance program.
y
Before disassembling, empty captured material in the
outlet manifold by turning the pump upside down to
drain material from the pump.
FLUID SECTION DISASSEMBLY
1.
Remove (61) outlet manifold, (60) inlet manifold.
2.
Remove (22) balls, (19) “O” rings (where applicable) and
(21) seats.
3.
Remove (15) fluid caps.
NOTE:
Only PTFE diaphragm models use a primary dia-
phragm (7) and a backup diaphragm (8). Refer to the auxilia-
ry view in the Fluid Section illustration.
4.
Remove the (6) diaphragm washer, (7) or (7 / 8) dia-
phragms, and (5) backup washer.
NOTE
: Do not scratch or mar the surface of (1) diaphragm
rod.
FLUID SECTION REASSEMBLY
y
Reassemble in reverse order. Refer to the torque require-
ments on page 6.
y
Clean and inspect all parts. Replace worn or damaged
parts with new parts as required.
y
Lubricate (1) diaphragm rod and (144) “U” cup with Lu-
briplat
FML-2 grease (94276 grease packet is included in
service kit).
y
For models with PTFE diaphragms: Item(8) Santoprene
diaphragm is installed with the side marked “AIR SIDE” to-
wards the pump center body. Install the PTFE diaphragm
(7) with the side marked “FLUID SIDE” towards the (15)
fluid cap.
y
Re-check torque settings after pump has been re-started
and run a while.
GENERAL DESCRIPTION
The ARO diaphragm pump offers high volume delivery even
at low air pressure and a broad range of material compat-
ibility options available. Refer to the model and option chart.
ARO pumps feature stall resistant design, modular air motor
/ fluid sections.
Air operated double diaphragm pumps utilize a pressure
differential in the air chambers to alternately create suction
and positive fluid pressure in the fluid chambers, ball checks
ensure a positive flow of fluid.
Pump cycling will begin as air pressure is applied and it will
continue to pump and keep up with the demand. It will build
and maintain line pressure and will stop cycling once maxi-
mum line pressure is reached (dispensing device closed) and
will resume pumping as needed.
AIR AND LUBE REQUIREMENTS
WARNING
EXCESSIVE AIR PRESSURE. Can cause pump
damage, personal injury or property damage.
y
A filter capable of filtering out particles larger than 50
microns should be used on the air supply. There is no lu-
brication required other than the “O” ring lubricant which
is applied during assembly or repair.
y
If lubricated air is present, make sure that it is compatible
with the Nitrile “O” rings in the air motor section of the
pump.
OPERATING INSTRUCTIONS
y
Always flush the pump with a solvent compatible with
the material being pumped if the material being pumped
is subject to “setting up” when not in use for a period of
time.
y
Disconnect the air supply from the pump if it is to be in-
active for a few hours.
y
The outlet material volume is governed not only by the
air supply but also by the material supply available at the
inlet. The material supply tubing should not be too small
or restrictive. Be sure not to use hose which might col-
lapse.
y
When the diaphragm pump is used in a forced-feed
(flooded inlet) situation it is recommended that a “Check
Valve” be installed at the air inlet.
y
Secure the diaphragm pump legs to a suitable surface to
ensure against damage by vibration.
y
Loctite® and 242® are registered trademarks of Henkel Loctite Corporation
y
ARO® is a registered trademark of Ingersoll-Rand Company
y
y
Santoprene® is a registered trademark of ExxonMobil
y
Lubriplate® is a registered trademark of Lubriplate Lubricants Company
y
