Nordson EFD 781Mini Series User manual

781Mini Series Spray Valve
Operating Manual
™
Electronic pdf les of Nordson EFD
manuals are also available at
www.nordsonefd.com

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781Mini Series Spray Valve
2
You have selected a reliable, high-quality dispensing system from Nordson EFD, the world leader in uid
dispensing. The 781Mini™spray valve was designed specically for industrial dispensing and will provide
you with years of trouble-free, productive service.
This manual will help you maximize the usefulness of your 781Mini valve.
Please spend a few minutes to become familiar with the controls and features. Follow our recommended
testing procedures. Review the helpful information we have included, which is based on more than
50years of industrial dispensing experience.
Most questions you will have are answered in this manual. However, if you need assistance, please do
not hesitate to contact EFD or your authorized EFD distributor. Detailed contact information is provided
on the last page of this document.
The Nordson EFD Pledge
Thank You!
You have just purchased the world’s nest precision dispensing equipment.
I want you to know that all of us at Nordson EFD value your business and will do everything in our power
to make you a satised customer.
If at any time you are not fully satised with our equipment or the support provided by your Nordson
EFD Product Application Specialist, please contact me personally at 800.556.3484 (US), 401.431.7000
(outside US), or [email protected].
I guarantee that we will resolve any problems to your satisfaction.
Thanks again for choosing Nordson EFD.
Srini Subramanian, General Manager
Srini Subramanian

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781Mini Series Spray Valve
3
Contents..........................................................................................................................................................................3
Introduction .....................................................................................................................................................................4
How the 781Mini Valve Operates.................................................................................................................................4
How the QR Clasp Works............................................................................................................................................5
How to Control the 781Mini Valve ...............................................................................................................................5
Specications..................................................................................................................................................................6
Operating Features..........................................................................................................................................................6
Installation .......................................................................................................................................................................7
Mounting the Valve on the Dispensing Equipment......................................................................................................7
Installing a 90° Fluid Inlet Fitting..................................................................................................................................7
Making the System Connections.................................................................................................................................8
ValveMate 8040 System with a 781Mini Valve.........................................................................................................8
ValveMate 7140 System with a 781Mini Valve.........................................................................................................9
Round Pattern Spray Area Coverage............................................................................................................................10
Valve Stroke Calibration ................................................................................................................................................10
Service...........................................................................................................................................................................11
Cleaning the Wetted Parts .........................................................................................................................................11
Replacing a Valve Component (Full Disassembly and Reassembly).........................................................................14
Replacement Parts........................................................................................................................................................16
Troubleshooting.............................................................................................................................................................17
Contents

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781Mini Series Spray Valve
4
Introduction
The 781Mini precision Low Volume Low Pressure
(LVLP) liquid spray valve is designed for high transfer
efciency without overspray or airborne mist and
provides consistent coating application of low-to-
medium viscosity uids. 781Mini spray valves are
simple to use and will operate many millions of cycles
without maintenance.
The uid body offers 360° rotational movement,
allowing the uid inlet to be positioned in the best
orientation for uid feed to the valve.
The valve’s unique quick-release (QR) clasp secures
the uid body to the air cylinder body and can be
removed in seconds for fast change-out and easy
cleaning and maintenance of the valve’s wetted parts.
How the 781Mini Valve Operates
Input air pressure at 4.8 bar (70 psi) retracts the
piston and needle from the needle seat in the nozzle,
permitting uid ow through the nozzle. At the same
time, nozzle air ows around the liquid exiting the
nozzle. This adjustable nozzle air creates a pressure
drop around the nozzle, causing the liquid to atomize
into ne droplets.
The amount sprayed is controlled by the valve open
time, reservoir pressure, and needle stroke. The area
of coverage is determined by the nozzle size and the
distance between the nozzle and the work surface.
Once the cycle is complete, air pressure is exhausted,
causing the piston spring to return the needle back to
its position in the nozzle, stopping uid ow.
Fluid body
rotates for 360°
movement
QR clasp can be
removed for fast
valve change-out
Closed Open

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781Mini Series Spray Valve
5
How the QR Clasp Works
The QR clasp slides into grooves to wedge the uid
body against the air cylinder body. A thumbscrew
secures the entire valve assembly to prevent movement
during cycling. The thumbscrew also acts like a jack
screw to ease QR clasp removal.
Groove for QR
clasp
QR clasp and
thumbscrew
Air cylinder
body
How to Control the 781Mini Valve
Two controllers are recommended for use with the 781Mini
spray valve: the ValveMate™8040 and the ValveMate™7140.
For multiple valve installations, use the ValveMate8040
controller to provide easy adjustment of valve output
for maximum end-user convenience and efciency. The
ValveMate 8040 controller puts push-button adjustment of
valve open time where it needs to be — at the valve.
The ValveMate 8040 features micro-processor circuitry for
extremely precise control of deposit size. Feed lines can
be purged, initial deposit sizes set, and adjustments made
quickly and easily at the dispensing station, without stopping
the production line.
For single valve installations, use the ValveMate 7140
controller. Incorporating programmable dispense time, digital
time readout, keypad programming for easy user interface,
and input / output communication with host machine PLCs,
the ValveMate 7140 has been designed with the machine
builder and operator in mind. The objectives are to bring
dispensing control close to the point of application and to
provide the features necessary to make setup and operation
as easy and precise as possible.

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781Mini Series Spray Valve
6
Specifications
NOTE: Specications and technical details are subject to engineering changes without prior notication.
Item Specification
Size 71.4 mm length x 22.4 mm diameter
(2.8 x 0.9")
Weight 141 g (5 oz)
Actuating air pressure required 4.8–6.2 bar (70–90 psi)
Maximum uid pressure 7.0 bar (100 psi)
Fluid inlet M5
Mounting M4
Cycle rate Exceeds 400 per minute
Actuating air inlet 4 mm OD tubing, barb tting
Air cylinder body 303 stainless steel
Fluid body 303 stainless steel
Air cap 303 stainless steel
Piston 303 stainless steel
Needle 303 stainless steel
Maximum operating temperature 102º C (215º F)
All stainless steel valve parts are passivated.
US Patent No. 9,816,849 for QR clasp.
Operating Features
Adjustable cap with stroke control knob for
additional calibration
90° air inlet
push-in tting
Air cylinder body
90° uid inlet tting
(included)
Straight uid inlet
tting (included)
QR clasp
Fluid body
Retaining nut /
air cap / nozzle
assembly

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781Mini Series Spray Valve
7
Installation
NOTE: Prior to installing the valve, read the associated
reservoir and valve controller operating manuals to become
familiar with the operation of all components of the dispensing
system.
Mounting the Valve on the Dispensing
Equipment
1. Mount the valve using the M4 mounting hole opposite the
QR clasp.
CAUTION
Do not over-tighten the QR clasp thumb screw. Doing so can
break the screw.
2. Orient the uid body and install the QR clasp as follows:
a. Partially thread the QR clasp thumbscrew into the air
cylinder body.
b. When the thumbscrew is engaged, rotate the uid
body to the required alignment based on the use of a
90°uid inlet tting.
c. Finger-tighten the thumbscrew to fully secure uid
body to the air cylinder body.
Installing a 90° Fluid Inlet Fitting
1. Thread the tting nut fully onto the 90° uid inlet tting
(towards the luer tting).
2. Fully thread the 90° uid inlet tting assembly into the
valve uid body, then unthread the assembly until the luer
tting is at the desired orientation.
NOTE: Do not unthread the 90° uid inlet tting more than
one (1) turn.
3. Use an 8-mm wrench to tighten the tting nut against the
uid body.
QR clasp
Mounting bracket
(P/N 7360613,
optional)
Valve uid
body 90° uid inlet
tting nut
Luer tting

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781Mini Series Spray Valve
8
Making the System Connections
For complete installation, setup, and testing instructions, refer to the controller operating manual.
ValveMate 8040 System with a 781Mini Valve
NOTE: The area of spray coverage is determined (1) by the distance between the spray valve nozzle and the work surface and
(2) by the stroke adjustment and uid pressure. Refer to “Round Pattern Spray Area Coverage” on page 10 to determine the
distance.
Always de-pressurize the uid reservoir before opening it. To do this, slide the shutoff valve on the air line away from the reservoir.
Before opening the reservoir, check the pressure gauge to verify that pressure is zero (0). If using an EFD tank, also open the
pressure relief valve.
On all EFD cartridge reservoirs, the unique threaded design provides fail-safe air pressure release during cap removal.
CAUTION
1. Connect the valve actuating air tubing
(white) and the nozzle air tubing
(black) to the ValveMate 8040 dual
solenoid pack used to control valve
open time (white) and nozzle air
(black).
2. Connect the white male quick-
connect on the constant air line to the
white female quick-connect on the
5-micron lter / regulator.
3. Install the syringe barrel reservoir
on the uid inlet tting (for use with
Optimum® syringe barrels). For low
viscosity uids, ll the reservoir after
installing it on the uid inlet tting.
NOTE: Fill syringe barrel reservoirs no
more than 2/3full.
4. Attach the syringe barrel adapter
to the barrel reservoir using the air
interconnect coupler to connect the
adapter to the uid pressure regulator
air line.
5. Set the uid pressure regulator to
low for thin uids and higher for thick
uids.
6. Use the MODE button on the
ValveMate controller to place the
controller in the PURGE mode. In the
PURGE mode only, channels 1 and
3 can be selected independently
without nozzle air pressure.
7. Use the stroke control knob on the
781Mini valve to set the desired ow
rate. Lower strokes (< 5) will produce
smaller patterns. Check the ow rate
by actuating the controller in the TIME
OVERRIDE mode.
NOTE: Make valve stroke
adjustments only when the valve is
not cycling.
8. Set the nozzle air pressure to 0.7 bar
(10 psi) and actuate the controller.
The valve will produce a ne spray.
To change uid ow, use the stroke
control knob and / or the reservoir
pressure. To change the nozzle air,
use the nozzle air pressure regulator.
Higher pressures will provide ner
spray.
NOTE: The 5-micron lter / regulator
assembly is not included. Order
separately:
7020584: 0–100 psi lter / regulator
7020585: 0–15 psi lter / regulator
Nozzle air pressure
regulator
5-micron lter /
regulator
781Mini valve
30 cc syringe barrel
Constant air
Fluid pressure
regulator
Constant uid
pressure
Valve actuating air (white)
ValveMate 8040
Controller
Plant air
4.8–6.8 bar
(70–90 psi)
Dual solenoid pack
Nozzle air (black)
Solenoid cables
Fluid inlet tting

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781Mini Series Spray Valve
9
Making the System Connections (continued)
For complete installation, setup, and testing instructions, refer to the controller operating manual.
ValveMate 7140 System with a 781Mini Valve
Always de-pressurize the uid reservoir before opening it. To do this, slide the shutoff valve on the air line away from the reservoir.
Before opening the reservoir, check the pressure gauge to verify that pressure is zero (0). If using an EFD tank, also open the
pressure relief valve.
On all EFD cartridge reservoirs, the unique threaded design provides fail-safe air pressure release during cap removal.
CAUTION
1. Connect the valve actuating air tubing
(white) and the nozzle air tubing
(black) to the corresponding outputs
on the back of the 7140 controller.
2. Connect the constant air supply to
the 5-micron lter / regulator.
3. Install the syringe barrel reservoir
on the uid inlet tting (for use with
Optimum syringe barrels) and connect
the uid supply to the valve. For low
viscosity uids, ll the reservoir after
installing it on the uid inlet tting.
NOTE: Fill syringe barrel reservoirs no
more than 2/3full.
4. Attach the syringe barrel adapter
to the barrel reservoir using the air
interconnect coupler to connect the
adapter to the uid pressure regulator
air line.
5. Set the uid pressure regulator to
low for thin uids and higher for thick
uids.
6. Use the MODE button on the
ValveMate controller to place the
controller in the PURGE mode. In the
PURGE mode only, channels 1 and
2 can be selected independently
without nozzle air pressure.
7. Use the stroke control knob on the
781Mini valve to adjust the pattern.
Lower strokes (< 5) will produce
smaller patterns. Check the ow rate
by actuating the controller in the TIME
OVERRIDE mode.
NOTE: Make valve stroke
adjustments only when the valve is
not cycling.
8. Set the nozzle air pressure to 0.7 bar
(10 psi) and actuate the controller.
The valve will produce a ne spray.
To change uid ow, use the stroke
control knob and / or the reservoir
pressure. To change the nozzle air,
use the nozzle air pressure regulator
(located on the front of the 7140).
Higher pressures will provide ner
spray.
NOTE: The 5-micron lter / regulator
assembly is not included. Order
separately:
7020584: 0–100 psi lter / regulator
7020585: 0–15 psi lter / regulator
NOTE: The area of spray coverage is determined (1) by the distance between the spray valve nozzle and the work surface and
(2) by the stroke adjustment and uid pressure. Refer to “Round Pattern Spray Area Coverage” on page 10 to determine the
distance.
5-micron lter /
regulator
781Mini valve
Fluid inlet tting
Plant air
4.8–6.8 bar
(70–90 psi)
ValveMate 7140
Controller
Constant uid pressure
Fluid pressure
regulator
Constant air
Valve
actuating air
(white)
Nozzle air
(black)
30 cc syringe barrel

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781Mini Series Spray Valve
10
Valve Stroke Calibration
The stroke control reference ring of each 781Mini valve is factory
calibrated to the zero position. After cleaning, disassembly,
and reassembly, the stroke control zero position may require
recalibration.
CAUTION
Before any component change or service activity, relieve air
pressure from the uid reservoirs.
CAUTION
Do not over-tighten the stroke control knob past the stop point of
clockwise rotation. Doing so can damage the assembly.
1. Make a note of the current stroke number setting.
2. Turn the stroke control knob clockwise until it bottoms out.
If the zero on the reference ring does not match up with the
reference mark on the actuator body, adjustment is needed.
3. Use a wrench to loosen the set screw.
4. Turn only the stroke reference ring until the 0 position lines up
with the reference mark on the air cylinder body.
5. Tighten the set screw.
6. Return the stroke control knob to the stroke number setting
noted in step 1.
Round Pattern Spray Area Coverage
Nozzle
Nozzle Distance from the Work Surface
2.54 mm
(0.1")
6.35 mm
(0.25")
12.7 mm
(0.5")
25.4 mm
(1.0")
38.1 mm
(1.5")
50.8 mm
(2.0")
76.2 mm
(3.0")
P/N 7361625:
Valve, spray,
781Mini, 0.01"
(0.254 mm)
1 mm
(0.04")
7.5 mm
(0.30")
8.25 mm
(0.325")
13.0 mm
(0.50")
15 mm
(0.60") n/a n/a
P/N 7362301:
Valve, spray,
781Mini, 0.03"
(0.76 mm)
7 mm
(0.275")
7.5 mm
(0.30")
10 mm
(0.40")
13 mm
(0.50")
15 mm
(0.60")
19 mm
(0.75")
25.5 mm
(1.0")
Stroke control
knob
Stroke reference
ring (shows the
stroke number
setting)
Set screw
Reference mark on
air cylinder body

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781Mini Series Spray Valve
11
Service
Perform these service procedures as needed for the best valve operation. You will need the following tools:
• 0.035" hex wrench (included)
• 1.5 and 2.5 mm hex wrenches (included)
• 3 mm hex wrench (included)
• Snap-ring pliers (not included)
• Adjustable wrench (not included)
CAUTION
Before any component change or service activity, relieve air pressure from the uid reservoirs.
Cleaning the Wetted Parts
Disassemble the Wetted Parts
1. Disconnect the actuating air, nozzle air, and uid supply from
the valve.
2. Make a note of the current stroke setting number.
3. Loosen the stroke control knob until the spring pressure is
relieved.
4. Turn the QR clasp thumbscrew counterclockwise to disengage
the clasp.
5. Carefully move the uid body downward until it clears the
needle-and-piston assembly.
6. Remove the double-stacked O-rings from inside the uid
body (these O-rings typically remain in the uid body after it is
removed).
7. Remove the uid inlet tting and the nozzle air tting.
8. Remove the air cap retaining nut and then remove the air cap
and the nozzle components.
Clean the Wetted Parts
1. Clean the uid body, nozzle, dispersion ring, air cap, and air
cap retaining nut in an appropriate solvent.
CAUTION
Do not clean the needle with an abrasive material, specically in
chemically sensitive applications.
2. Clean the needle with a cloth dampened in solvent.
Nozzle (PEEK
nozzle shown)
Air cap
Air cap
retaining nut
Fluid inlet
tting
QR clasp
Double-stacked
O-rings
Nozzle air
tting
Fluid body
Removing the fluid body
Removing the nozzle
Stroke control
knob
Nozzle O-ring
Nozzle
dispersion ring

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781Mini Series Spray Valve
12
Cleaning the Wetted Parts (continued)
Reassemble the Wetted Parts
1. Lubricate the nozzle O-ring with uorocarbon grease and
reassemble the nozzle components.
CAUTION
Do not over-tighten the nozzle. Doing so can damage the assembly.
2. Reinstall the nozzle assembly, ensuring that the dispersion
ring tab ts into the notch on the uid body. Depending on the
nozzle material, tighten the nozzle to the following torque:
Nozzle Size Material Torque
0.01" (0.254 mm) Stainless steel 1.4 N•m (12 in.-lb)
0.03" (0.76 mm) PEEK 0.1N•m(1 in.-lb) max.
Service (continued)
Correct installation location for the
fluid inlet fitting
Correct installation location for the
nozzle air fitting
3. Install the uid inlet tting in the uid inlet side of the uid body.
If installing a 90° uid inlet tting, refer to “Installing a 90° Fluid
Inlet Fitting” on page 7 to install the tting in the desired
orientation. Return here to continue.
NOTE: Ensure that the uid inlet tting is installed on the
uid inlet side of the uid body. A uid symbol indicates the
uid inlet.
4. Install the nozzle air tting in the uid body.
NOTE: Ensure that the nozzle air tting is installed on the air
inlet side of the uid body. An air symbol indicates the air
inlet.
5. Install a replacement double-stacked O-ring set on the needle.
NOTE: Lubricate double-stacked O-rings before installing.
Use the supplied uorocarbon grease only if the assembly uid
being dispensed is compatible with it.
6. Use one hand to position the uid body on the air cylinder /
needle assembly and then slide the QR clasp into the grooves
on the air cylinder body.
Nozzle (PEEK
nozzle shown)
Nozzle O-ring
Dispersion
ring tab
Notch on
uid body for
dispersion ring tab
Groove for
QR clasp
Double-
stacked
O-rings

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781Mini Series Spray Valve
13
CAUTION
Do not over-tighten the QR clasp thumb screw. Doing so can break
the screw.
7. Fully install the QR clasp as follows:
a. Partially thread the QR clasp thumbscrew into the air
cylinder body.
b. When the thumbscrew is engaged, rotate the uid body to
the required alignment.
c. Finger-tighten the thumbscrew to fully secure uid body to
the air cylinder.
8. Reconnect the actuating air, nozzle air, and uid supply to the
valve.
9. Turn the stroke control knob clockwise until it bottoms out.
If the zero on the reference ring does not match up with the
reference mark on the actuator body, adjustment is needed.
Refer to “Valve Stroke Calibration” on page 10.
Zero (0) and reference mark lined up,
indicating that the stroke control is
properly calibrated.
Service (continued)
Cleaning the Wetted Parts (continued)
Reassemble the Wetted Parts (continued)

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781Mini Series Spray Valve
14
Service (continued)
CAUTION
Before any component change or service activity, relieve air pressure from the uid reservoirs.
CAUTION
After a needle and nozzle are used together, do not replace either component with a different needle or nozzle.
When replacing a needle, also replace the corresponding nozzle. Failure to replace needles and nozzles together
can create a poor seal, causing leakage.
Replacing a Valve Component (Full Disassembly
and Reassembly)
Disassemble the Valve
1. Make a note of the current stroke setting number.
2. Turn the stroke control knob counterclockwise to fully open.
3. Remove the stroke control assembly.
4. Remove the spring from air cylinder body.
5. Use snap ring pliers to remove the piston retaining ring.
WARNING
The needle is very sharp. Handle it cautiously to prevent injury.
CAUTION
Do not grasp the needle with pliers. Doing so can damage the
needle.
6. Carefully pull the needle-and-piston assembly out of the air
cylinder body.
NOTES:
• The needle-and-piston assembly cannot be disassembled.
• The stroke control and piston O-rings are the same size.
7. Remove the U-cup seal from the inside of the uid body only if
it needs to be replaced.
8. Turn the QR clasp thumbscrew counterclockwise to disengage
the QR clasp and then remove the clasp.
9. Remove the double-stacked O-rings from inside the uid
body (these O-rings typically remain in the uid body after it is
removed).
10. Remove the uid inlet tting and nozzle air tting.
11. Remove the air cap retaining nut and then remove the air cap
and the nozzle components.
Stroke control assembly
with O-ring
Air cylinder body
Needle-and-piston
assembly
Piston O-ring
Spring
Piston retaining
ring
Air cap
Air cap
retaining nut
Fluid body
Fluid inlet
tting
Nozzle air
tting
Double-stacked
O-rings
U-cup seal
Nozzle (PEEK nozzle
shown)
Nozzle O-ring
Nozzle dispersion ring

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781Mini Series Spray Valve
15
Replacing a Valve Component (Full
Disassembly and Reassembly)
(continued)
CAUTION
Replacement parts for 0.01" and 0.03" valves are not
interchangeable:
• Use the correct replacement parts based on the size of the
valve.
• Do not attempt to convert a 0.01" valve to a 0.03" valve, or vice
versa.
Reassemble the Valve
Reassemble the valve in the reverse order of disassembly (refer
to “Disassemble the Valve” on page 14). Perform the following
actions as you reassemble the valve:
• Replace damaged or worn components.
• Always replace the needle-and-piston assembly and the nozzle
together if one of these components is damaged or worn.
• Lubricate O-rings with the supplied uorocarbon grease
(P/N7014917) only if the assembly uid being dispensed is
compatible with it.
• If reinstalling the U-cup seal, lubricate it with the supplied
grease and ensure that it is in the correct orientation.
• Ensure that inlet ttings are connected to the correct inlet port.
Air and uid symbols are provided on the uid body. Refer
to “Reassemble the Wetted Parts” on page 12 for detailed
reassembly steps for the wetted parts.
• Recalibrate the stroke control knob if needed.
Correct orientation of the U-cup seal
Zero (0) and reference mark lined up,
indicating that the stroke control is
properly calibrated.
Correct installation location for the
fluid inlet fitting
Correct installation location for the
nozzle air fitting

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781Mini Series Spray Valve
16
Replacement Parts
7361405
QR clasp
7361989
Piston retaining ring (2 pack)
7361991
Air cylinder body
7361990
Stroke control
knob assembly
7361398
90° air inlet tting
7361986
Nozzle air cap
retaining nut
Nozzle O-ring kit (2 pack)
7361987 Viton
7363361 EPDM
7363360 Silicone
7361984
Nozzle assembly and air cap,
stainless steel, 0.01"
7362306
Nozzle assembly and air cap,
PEEK, 0.03"
NOTE: Stainless steel nozzle shown.
7361988
Fluid body
7361411
90° uid inlet
tting
OR
7361983
Needle-and-piston assembly, 0.01"
(includes spring and retaining ring)
7362307
Needle-and-piston assembly, 0.03"
(includes spring and retaining ring)
7028737
U-cup seal
Double-stacked O-rings
7361407 Viton (brown)
7361408 EPR (black)
7361409 Silicone (orange)
7020671
M5 uid inlet tting
with barb
Valve Part Numbers
Part # Description Nozzle Orifice Spray Pattern
7361625 781Mini-0.01" spray valve 0.254 mm (0.01") Round
7362301 781Mini-0.03" spray valve 0.76 mm (0.03") Round
Additional Parts and Supplies
Part Number Description
7361985 Seal kit (includes U-cup seal and all Viton O-rings)
7362062 Bushing kit (2 pack)
7360613 Mounting bracket
7028765 M4 thread mounting rod
7014917 Fluorocarbon grease (for lubricating O-rings; before using, ensure
compatibility with the uid being dispensed)
CAUTION
Replacement parts for 0.01" and 0.03"
valves are not interchangeable:
• Use the correct replacement parts
based on the size of the valve.
• Do not attempt to convert a 0.01"
valve to a 0.03" valve, or vice versa.
OR
Spring-energized seal
7362507 Carbon-lled PTFE
(for reactive adhesives)

www.nordsonefd.com [email protected] 800-556-3484 Sales and service of Nordson EFD dispensing systems are available worldwide.
781Mini Series Spray Valve
17
Troubleshooting
Problem Possible Cause Corrective Action
No uid ow Valve operating air pressure too low Increase air pressure to 4.8bar (70psi)
minimum.
Fluid reservoir air pressure too low Increase the air pressure to the uid
reservoir.
Needle stroke adjusted to the closed
position (0 stroke)
Open the stroke adjustment. If
adjustment is needed, refer to “Valve
Stroke Calibration” on page 10.
Clogged nozzle Clean the nozzle. Refer to “Cleaning the
Wetted Parts” on page 11.
Actuating air and nozzle air supplies
reversed
Check the air supply connections.
Valve not providing clean shutoff, leaving
buildup on the nozzle
Needle not properly seated Remove the nozzle, clean the needle and
nozzle, and replace worn or damaged
parts.
Fluid ows from the nozzle but will not
spray
Nozzle air pressure too low Increase the nozzle air pressure.
Air passage between nozzle and air cap
obstructed
Remove the air cap and clean the air cap
and nozzle.
Fluid viscosity too high If the uid viscosity is too high, it will
not atomize. Increase the nozzle air
pressure.
Steady drip Damaged needle, debris in needle seat,
or improper valve assembly
Replace the damaged needle. Whenever
replacing a needle, also replace the
nozzle.
Fluid leaks from drain hole Worn O-ring seals Replace the double-stacked O-rings.
Refer to “Cleaning the Wetted Parts” on
page 11.
Inconsistent deposit size Value actuating air pressure and / or uid
reservoir air pressure uctuating or valve
actuating air pressure less than 4.8bar
(70psi)
Make sure that the valve and uid
reservoir air pressures are constant and
that the valve actuating air pressure is
4.8bar (70psi).
Valve open time inconsistent The time the valve is open must be
constant. Make sure the valve controller
is providing a consistent output.

For Nordson EFD sales and service in over
40 countries, contact Nordson EFD or go to
www.nordsonefd.com.
Global
East Providence, RI USA
800-556-3484; [phone]
[email protected]
Europe
Dunstable, Bedfordshire, UK
0800 585733; [phone]
[email protected]
Asia
China: [phone]; [email protected]
India: [phone]; [email protected]
Japan: [phone]; [email protected]
Korea: [phone]; [email protected]
SEAsia: [phone]; [email protected]
Viton is a registered trademark of E.I. DuPont.
The Wave Design is a trademark of Nordson Corporation.
©2018 Nordson Corporation 7362159 v050118
NORDSON EFD ONE YEAR LIMITED WARRANTY
Nordson EFD products are warranted for one year from date of purchase to be free from
defects in material and workmanship (but not against damage caused by misuse, abrasion,
corrosion, negligence, accident, faulty installation or by dispensing material incompatible
with equipment) when the equipment is installed and operated in accordance with factory
recommendations and instructions. Nordson EFD will repair or replace free of charge any
part of the equipment thus found to be defective, on authorized return of the part prepaid to
our factory during the warranty period. In no event shall any liability or obligation of Nordson
EFD arising from this warranty exceed the purchase price of the equipment. This warranty is
valid only when oil-free, clean, dry, ltered air is used.
Nordson EFD makes no warranty of merchantability or tness for a particular purpose. In no
event shall Nordson EFD be liable for incidental or consequential damages.