Nordson EFD 754V-SS Manual

754V-SS Dispense Valve
MAINTENANCE & PARTS GUIDE
IMPORTANT!
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contact EFD or go to www.efd-inc.com/contact
EFD, Inc.
East Providence, RI USA
800-556-3484; [phone] (outside the USA)
[email protected] www.efd-inc.com
EFD International Inc.
Dunstable, Bedfordshire, UK
0800 585733 or [phone]
Ireland 00800 8272 9444
[email protected] www.efd-inc.com
EFD, Inc., Asia
China: [phone]
[email protected] www.efd-inc.com/cn
Singapore: [phone] [email protected]
®
A NORDSON COMPANY

Fluid Body
1. Remove the two retainer screws.
2. To reinstall the fluid body, align fluid
body holes with diaphragm and air
cylinder body holes and reinsert
retainer screws. Torque to 1.58 Nm
(14 inch pounds).
Diaphragm
3. Back out stroke control two turns
counterclockwise from the closed
position.
4. Remove fluid body.
5. Unscrew diaphragm (counter-
clockwise) and remove it from the
piston rod.
6. Thread on the new diaphragm
and tighten slowly until
diaphragm bottoms against
piston shaft.
7. Align the holes of the diaphragm
with the appropriate holes in the
air cylinder body by inserting a
flat tip screwdriver through the
hole in the stroke control and
engage piston rod slot.
8. Rotate rod, piston and diaphragm
assembly clockwise until holes
are aligned.
9. Reinstall fluid body and torque
retainer screws to value specified
in step 2.
10. Turn stroke control clockwise until
closed, and then reopen to
desired stroke.
Valve Disassembly
and Reassembly Procedures
12
4
5
6
7
9
11
17
Tip retaining nut
#75405
(2) Retaining screws
#HM3X16SHC Fluid body
#75402
Fluid inlet fitting
#75410
Optional upchurch
fitting available;
specify part #75408
Diaphragm
#7510TKIT
Teflon®O-ring
#75411T
www.efd-inc.com [email protected] USA 800-556-3484 Europe [phone] Asia [phone]
Sales and service of EFD dispensing systems are available worldwide.

Piston O-ring
11. Remove fluid body and
diaphragm.
12. Remove stroke control and spring
by turning counterclockwise.
13. Remove the piston retainer ring
and anti-torque washer.
14. Remove the piston.
15. Lubricate O-ring, piston shaft and
air cylinder wall with Magnalube-G.
16. Reinstall components in reverse
order of disassembly.
Cylinder O-ring
17. Remove fluid body and diaphragm.
18. Remove stroke control knob and
spring by turning counterclockwise.
19. Remove the piston retainer ring,
anti-torque washer and piston.
20. Remove air cylinder retaining ring,
washer and O-ring.
21. Lubricate O-ring with Magnalube-G.
22. Reinstall components in reverse
order.
Tools required:
2.5 mm hex wrench
1/8" flat-tip screwdriver
6" adjustable wrench
6" needle-nose pliers
snap-ring pliers
8
15
3
10
12
13
16
18
19
20
21
22
Air cylinder body #75401
Air cylinder O-ring
#7520
O-ring retaining
washer #7527W-BL
O-ring retaining
ring #75406
Piston and rod includes O-ring (Viton)
#75403
Piston O-ring
#7519V
Anti-torque washer #7533
Piston retainer ring
#7526
Piston spring
#7525
Tamper-resist
stroke control
#75404
Air input hose & fitting
#75407A
Tamper-resist
stroke key #7547
www.efd-inc.com [email protected] USA 800-556-3484 Europe [phone] Asia [phone]
Sales and service of EFD dispensing systems are available worldwide.

Troubleshooting Guide
No fluid flow
•If valve operating air pressure is too low,
the valve will not open. Increase air
pressure to 70 psi (4.8 bar) minimum.
•The reservoir air pressure may not be
high enough. Increase pressure.
•The dispensing tip may be clogged.
Replace tip.
•The stroke adjustment may be closed.
Open stroke adjustment.
•Fluid may have solidified in the valve.
Clean the fluid body.
Fluid drools after the valve
closes, eventually stopping
•This is caused when air is trapped in
the outlet section of the fluid body or
the fluid has entrapped air. The air will
expand after the valve closes, causing
extrusion until the air reaches
atmospheric pressure.
Purge the valve by dispensing at a steady
flow until clear. If a small tip is used, it
may be necessary to remove the tip while
purging to obtain sufficient flow to carry
the air down through the tip adapter.
•If the fluid has entrapped air, the material
must be degassed before dispensing.
Fluid drips at a steady rate after
the valve closes
•A steady drip can be caused by excessive
reservoir pressure. Check to be sure
the reservoir pressure is not above 70
psi (4.8 bar).
•A steady drip also indicates failure of
the diaphragm to close fully due to
particle build-up or wear. In either case,
replace the sealing head in accordance
with the maintenance instructions.
Fluid leaks out between fluid
body and diaphragm
•Fluid leakage between the fluid body and
diaphragm indicates the annular sealing
ridge on the fluid body is damaged or the
fluid body is distorted due to excessive
torque on the retaining screws. In either
case, replace the fluid body.
Fluid flows out of the drain hole
•Fluid flowing out of the drain hole
indicates a ruptured diaphragm.
Replace in accordance with the
maintenance instructions.
Valve responds slowly when
opening and closing
•Valve response is related to control air
hose length and size. The valve is
supplied with 5-feet of 3/32” ID tubing
attached. Any additional length or size
change will affect response time. Check
to be sure the length and size have not
been changed.
Inconsistent deposits
•Inconsistent deposits can result if the
air pressure controlling the valve and/or
supplying the reservoir is fluctuating or if
the valve operating pressure is less than
70 psi (4.8 bar). Check to be sure air
pressures are constant and the valve
operating pressure is 70 psi (4.8 bar).
•The time the valve is open must be
constant. Check to be sure the valve
controller is providing a consistent
output.
A NORDSON COMPANY
USA: 800-556-3484 or [phone]
Europe: 0800 585733 or [phone]
Asia: [phone]
[email protected] www.efd-inc.com
Teflon is a registered trademark of DuPont.
©2006 Nordson Corporation 754V-MAINT-01 v062606