Blagdon Pump B75 Non-Metallic - Manual (Page 29)

s30nmdl2sm-rev0312 Model B75 Non-Metallic Design Level 2 Page 29
2/07 Model B75 Non-Metallic Design Level 2 Page 26
DIAPHRAGM SERVICING
To service the diaphragms first shut
off the suction, then shut off the
discharge lines to the pump. Shut off the
compressed air supply, bleed the
pressure from the pump, and disconnect
the air supply line from the pump. Drain
any remaining liquid from the pump.
Step #1: See the pump composite
repair parts drawing, and the diaphragm
servicing illustration.
Using a 9 /
16
" wrench or socket,
remove the 16 capscrews (items 11), hex
nuts and washers that fasten the elbows
(items 19) to the outer chambers (items
15). Remove the elbows with the
manifolds and spacers attached.
Step #2: Removing the outer
chambers.
Using a 9 /
16
" wrench or socket,
remove the 20 capscrews (items 9 & 12),
hex nuts and washers that fasten the
outer chambers, diaphragms, and inner
chambers (items 16) together.
Step #3: Removing the diaphragm
assemblies.
Use a 1 3 /
8
" (35mm) wrench or six
pointed socket to remove the diaphragm
assemblies (outer plate, diaphragm, and
inner plate) from the diaphragm rod (item
33) by turning counterclockwise.
Insert a 1/4-20 capscrew or set screw
into the smaller tapped hole in the inner
diaphragm plate (item 30). Insert the
protruding stud and the 1/4-20 fastener
loosely into a vise. Use a 1
3 /
8
" wrench
or socket to remove the outer diaphragm
plate (item 29) by turning
counterclockwise. Inspect the
diaphragm (item 17) for cuts, punctures,
abrasive wear or chemical attack.
Replace the diaphragms if necessary.
Step #4: Installing the diaphragms.
Push the threaded stud of the outer
diaphragm plate through the center hole
of the diaphragm. Thread the inner plate
clockwise onto the stud. Use a torque
wrench to tighten the diaphragm
assembly together to 480 in Lbs. (54.23
Newton meters). Allow a minimum of 15
minutes to elapse after torquing, then
re-torque the assembly to compensate
for stress relaxation in the clamped
assembly.
Step #5: Installing the diaphragm
assemblies to the pump.
Make sure the bumper (item 6) is
installed over the diaphragm rod.
Thread the stud of the one diaphragm
assembly clockwise into the tapped hole
at the end of the diaphragm rod (item
33) until the inner diaphragm plate is flush
to the end of the rod. Insert rod into
pump.
Align the bolt holes in the diaphragm
with the bolt pattern in the inner chamber
(item 16). Make sure the molded
directional arrows on the diaphragm point
vertically.
Fasten the outer chamber (item 15)
to the pump, using the capscrews (items
9 & 12), hex nuts and flat washers.
On the opposite side of the pump,
pull the diaphragm rod out as far as
possible. Make sure the bumper (item
6) is installed over the diaphragm rod.
Thread the stud of the remaining
diaphragm assembly clockwise into the
tapped hole at the end of the diaphragm
rod (item 33) as far as possible and still
allow for alignment of the bolt holes in
the diaphragm with the bolt pattern in
the inner chamber. The molded
directional arrows on the diaphragm must
point vertically.
Fasten the remaining outer chamber
(item 15) to the pump, using the
capscrews (items 9 & 12), hex nuts and
flat washers.
Step #6: Re-install the elbow/spacer/
manifold assemblies to the pump, using
the capscrews (items 11), hex nuts and
flat washers.
The pump is now ready to be
re-installed, connected and returned to
operation.
OVERLAY DIAPHRAGM SERVICING
The PTFE overlay diaphragm (item
18) is designed to fit snugly over the
exterior of the standard TPE diaphragm
(item 17).
The molded directional arrows on the
overlay diaphragm must point vertically.
Follow the same procedures
described for the standard diaphragm for
removal and installation.
Read these instructions
completely, before in-
stallation and start-up. It
is the responsibility of
the purchaser to retain
this manual for reference. Failure to
comply with the recommendations stated
in this manual will damage the pump, and
void factory warranty.
IMPORTANT