hdb2smdl3sm-rev0217
Model HDB2 Page 7
REASSEMBLY
All procedures for reassembling the pump are the reverse of the disassembly
instructions with further instructions as shown:
The diaphragm assemblies are to be installed with the natural bulge outward or
toward the head of the center screw. Make sure both plates are installed with outer radii
against the diaphragm. After all components are in position in a vise and hand tight,
set a torque wrench for 40 ft. pounds (54.23 Newton meters) using a 1
1
/
8
" (2.857 cm)
socket. After each diaphragm sub assembly has been completed, thread one assembly
into the diaphragm rod. Make sure the 5/16-18 UNC capscrew has been removed
from the inner plate and the diaphragm rod bumper is in place on the diaphragm rod.
Install this sub assembly into the pump and secure by installing the outer chamber
in place and tightening the capscrews. This will hold the assembly in place while the
opposite side is installed. Install the second diaphragm assembly into the diaphragm
rod checking to see that the diaphragm rod bumper is in place. Tighten to 30 ft. lbs.
(40.67 Newton meters) torque before installing the outer chamber in place. If the holes
in the diaphragm flange do not align with the holes in the inner chamber flange, turn
the diaphragm assembly in the direction of tightening to align the holes so that the
capscrews can be inserted. This final torquing of the last diaphragm assembly will lock
the two diaphragm assemblies together. Secure the last outer chamber by tightening
down the securing nuts gradually and evenly. This tightening procedure should be
done on both sides.
When reinstalling check valves, take care that the seat gaskets are aligned properly
before securing porting flange in place.
A Note about Air Valve Lubrication
The SANDPIPER pump’s pilot valve and main air valve assemblies are designed
to operate WITHOUT lubrication. This is the preferred mode of operation. There
may be instances of personal preference, or poor quality air supplies when lubrica-
tion of the compressed air supply is required. The pump air system will operate with
properly lubricated compressed air supplies. Proper lubrication of the compressed air
supply would entail the use of an air line lubricator (available from Warren Rupp) set
to deliver one drop of 10 wt., non-detergent oil for every 20 SCFM of air the pump
consumed at its point of operation. Consult the pump’s published Performance Curve to
determine this.
It is important to remember to inspect the sleeve and spool set routinely. It should
move back and forth freely. This is most important when the air supply is lubricated.
If a lubricator is used, oil accumulation will, over time, collect any debris from the
compressed air. This can prevent the pump from operating properly.
Water in the compressed air supply can create problems such as icing or freez-
ing of the exhaust air causing the pump to cycle erratically, or stop operating. This
can be addressed by using a point of use air dryer to supplement a plant’s air drying
equipment. This device will remove excess water from the compressed air supply and
alleviate the icing or freezing problem.
ESADS+Plus
®
: Externally Serviceable Air Distribution
System
Please refer to the exploded view drawing and parts list in the Service Manual
supplied with your pump. If you need replacement or additional copies, contact your
local Warren Rupp Distributor, or the Warren Rupp factory Literature Department at
the number shown below. To receive the correct manual, you must specify the MODEL
and TYPE information found on the name plate of the pump.
The main air valve sleeve and spool set is located in the valve body mounted on
the pump with four hex head capscrews. The valve body assembly is removed from
the pump by removing these four hex head capscrews.
With the valve body assembly off the pump, access to the sleeve and spool set is
made by removing four hex head capscrews (each end) on the end caps of the valve
body assembly. With the end caps removed, slide the spool back and forth in the
sleeve. The spool is closely sized to the sleeve and must move freely to allow for proper
pump operation. An accumulation of oil, dirt or other contaminants from the pump’s
air supply, or from a failed diaphragm, may prevent the spool from moving freely.
