Graco PD44 Guide

3A7284B
EN
Operation - Parts
PD44 Metering Valve
for High Wear Material
Meter, mix, and dispense valve for precise, two-component micro-dispensing of high wear
material. For professional use only.
Part No. UA0421
See page 3for model information, including maximum
working pressures.
Important Safety Instructions
Read all warnings and instructions in this
manual and in all related manuals before
using the equipment. Save all
instructions.

2 3A7284B
Contents
Related Manuals . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Model Information . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Warnings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Important Iscocyanate (ISO) Information . . . . . . . . 7
Isocyanate Conditions . . . . . . . . . . . . . . . . . . . . . 7
Keep Components A and B Separate . . . . . . . . . 7
Moisture Sensitivity of Isocyanates . . . . . . . . . . . 7
Changing Materials . . . . . . . . . . . . . . . . . . . . . . . 8
A (Red) and B (Blue) Components . . . . . . . . . . . 8
Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Grounding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Component Identification . . . . . . . . . . . . . . . . . . . 10
Motor Driven PD44 Metering Valve . . . . . . . . . . 10
Typical System Configuration . . . . . . . . . . . . . . 11
Typical Feed System Components . . . . . . . . . . 12
Setup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Typical Installation . . . . . . . . . . . . . . . . . . . . . . . 13
PD44 Metering Valve Mounting Diagram. . . . . . 14
Motor Mounting Diagram . . . . . . . . . . . . . . . . . . 14
Custom Drive Mounting Diagram. . . . . . . . . . . . 15
Startup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Ratio Check. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Sequence of Operation . . . . . . . . . . . . . . . . . . . 18
Pressure Relief Procedure . . . . . . . . . . . . . . . . . . . 19
Shutdown. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Schematics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Rebuild. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Wetted Section Disassembly . . . . . . . . . . . . . . . 22
Spool Valve Rebuild . . . . . . . . . . . . . . . . . . . . . . 24
Wetted Section Rebuild . . . . . . . . . . . . . . . . . . . 25
Wetted Section Reassembly . . . . . . . . . . . . . . . 27
Parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Stepper Motor Drive Body . . . . . . . . . . . . . . . . . 30
Metering Rod and Spool Valve. . . . . . . . . . . . . . 32
High Viscosity Spool Valve. . . . . . . . . . . . . . . . . 33
Spool Air Piston Assembly . . . . . . . . . . . . . . . . . 34
Material Inlet Blocks . . . . . . . . . . . . . . . . . . . . . . 35
Standard Nose with 7/8-9 Thread. . . . . . . . . . . . 36
Accessories. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Electrical Requirements . . . . . . . . . . . . . . . . . . . . . 39
Technical Specifications . . . . . . . . . . . . . . . . . . . . 40
California Proposition 65 . . . . . . . . . . . . . . . . . . . . 41
Graco Standard Warranty . . . . . . . . . . . . . . . . . . . 42

Related Manuals
3A7284B 3
Related Manuals
Manuals are available at www.graco.com
Component manuals are in U.S. English.
Model Information
* The UA0421 model of the PD44 metering valve does not include a motor. You will need to supply a motor to
operate the valve.
Part Description
308116 Severe-Duty, UHMWPE/PTFE or PTFE
Packed Stainless Steel Pumps
308167 Low Volume Air Regulators
308168 High Volume Air Regulators
308169 Air Filters, Lubricators and Kits
313526 Check-Mate®Pump Packages
PD44 Metering
Valve Model
Maximum Outlet Fluid
Working Pressure
psi (MPa, bar)
Maximum Air
Working Pressure
psi (MPa, bar)
Maximum Inlet Working Pressure
psi (MPa, bar)
Metal Sleeves Plastic Sleeves
UA0421
Motor Driven* 2000 (14, 138) 100 (07, 7) 1200 (8, 83) 400 (2.8, 28)

Warnings
4 3A7284B
Warnings
The following warnings are for the setup, use, grounding, maintenance, and repair of this equipment. The
exclamation point symbol alerts you to a general warning and the hazard symbols refer to procedure-specific risks.
When these symbols appear in the body of this manual or on warning labels, refer back to these Warnings.
Product-specific hazard symbols and warnings not covered in this section may appear throughout the body of this
manual where applicable.
S
WARNING
SKIN INJECTION HAZARD
High-pressure fluid from dispensing device, hose leaks, or ruptured components will pierce skin. This
may look like just a cut, but it is a serious injury that can result in amputation. Get immediate surgical
treatment.
• Do not point dispensing device at anyone or at any part of the body.
• Do not put your hand over the fluid outlet.
• Do not stop or deflect leaks with your hand, body, glove, or rag.
• Follow the Pressure Relief Procedure when you stop dispensing and before cleaning, checking, or
servicing equipment.
• Tighten all fluid connections before operating the equipment.
• Check hoses and couplings daily. Replace worn or damaged parts immediately.
TOXIC FLUID OR FUMES HAZARD
Toxic fluids or fumes can cause serious injury or death if splashed in the eyes or on skin, inhaled or
swallowed.
• Read Safety Data Sheets (SDSs) for handling instructions and to know the specific hazards of the
fluids you are using, including the effects of long-term exposure.
• When spraying, servicing equipment, or when in the work area, always keep work area well-ventilated
and always wear appropriate personal protective equipment. See Personal Protective Equipment
warnings in this manual.
• Store hazardous fluid in approved containers, and dispose of it according to applicable guidelines.
PERSONAL PROTECTIVE EQUIPMENT
Always wear appropriate personal protective equipment and cover all skin when spraying, servicing
equipment, or when in the work area. Protective equipment helps prevent serious injury, including
long-term exposure; inhalation of toxic fumes, mists or vapors; allergic reaction; burns; eye injury and
hearing loss. This protective equipment includes but is not limited to:
• A properly fitting respirator, which may include a supplied-air respirator, chemically impermeable
gloves, protective clothing and foot coverings as recommended by the fluid manufacturer and local
regulatory authority.
• Protective eyewear and hearing protection.

Warnings
3A7284B 5
WARNING
FIRE AND EXPLOSION HAZARD
Flammable fumes, such as solvent and paint fumes, in work area can ignite or explode. Paint or solvent
flowing through the equipment can cause static sparking. To help prevent fire and explosion:
• Use equipment only in well-ventilated area.
• Eliminate all ignition sources; such as pilot lights, cigarettes, portable electric lamps, and plastic drop
cloths (potential static sparking).
• Ground all equipment in the work area. See Grounding instructions.
• Never spray or flush solvent at high pressure.
• Keep work area free of debris, including solvent, rags and gasoline.
• Do not plug or unplug power cords, or turn power or light switches on or off when flammable fumes
are present.
• Use only grounded hoses.
• Hold dispensing device firmly to side of grounded pail when triggering into pail. Do not use pail liners
unless they are anti-static or conductive.
•Stop operation immediately if static sparking occurs or you feel a shock.Do not use equipment until
you identify and correct the problem.
• Keep a working fire extinguisher in the work area.
EQUIPMENT MISUSE HAZARD
Misuse can cause death or serious injury.
• Do not operate the unit when fatigued or under the influence of drugs or alcohol.
• Do not exceed the maximum working pressure or temperature rating of the lowest rated system
component. See Technical Specifications in all equipment manuals.
• Use fluids and solvents that are compatible with equipment wetted parts. See Technical
Specifications in all equipment manuals. Read fluid and solvent manufacturer’s warnings. For
complete information about your material, request Safety Data Sheets (SDSs) from distributor or
retailer.
• Turn off all equipment and follow the Pressure Relief Procedure when equipment is not in use.
• Check equipment daily. Repair or replace worn or damaged parts immediately with genuine
manufacturer’s replacement parts only.
• Do not alter or modify equipment. Alterations or modifications may void agency approvals and create
safety hazards.
• Make sure all equipment is rated and approved for the environment in which you are using it.
• Use equipment only for its intended purpose. Call your distributor for information.
• Route hoses and cables away from traffic areas, sharp edges, moving parts, and hot surfaces.
• Do not kink or over bend hoses or use hoses to pull equipment.
• Keep children and animals away from work area.
• Comply with all applicable safety regulations.

Warnings
6 3A7284B
WARNING
MOVING PARTS HAZARD
Moving parts can pinch, cut or amputate fingers and other body parts.
• Keep clear of moving parts.
• Do not operate equipment with protective guards or covers removed.
• Equipment can start without warning. Before checking, moving, or servicing equipment, follow the
Pressure Relief Procedure and disconnect all power sources.
PLASTIC PARTS CLEANING SOLVENT HAZARD
Many cleaning solvents can degrade plastic parts and cause them to fail, which could cause serious
injury or property damage.
• Use only compatible solvents to clean plastic structural or pressure-containing parts.
• See Technical Specifications in all equipment manuals for materials of construction. Consult the
solvent manufacturer for information and recommendations about compatibility.

Important Iscocyanate (ISO) Information
3A7284B 7
Important Iscocyanate (ISO) Information
Isocyanate Conditions Keep Components A and B
Separate
Moisture Sensitivity of
Isocyanates
Exposure to moisture (such as humidity) will cause ISO
to partially cure, forming small, hard, abrasive crystal
that become suspended in the fluid. Eventually a film will
form on the surface and the ISO will begin to gel,
increasing in viscosity.
NOTE: The amount of film formation and rate of
crystallization varies depending on the blend of ISO, the
humidity, and the temperature.
Spraying or dispensing fluids that contain isocyanates
creates potentially harmful mists, vapors, and
atomized particulates.
• Read and understand the fluid manufacturer’s
warnings and Safety Data Sheets (SDSs) to know
specific hazards and precautions related to
isocyanates.
• Use of isocyanates involves potentially hazardous
procedures. Do not spray with this equipment
unless you are trained, qualified, and have read
and understood the information in this manual and
in the fluid manufacturer’s application instructions
and SDSs.
• Use of incorrectly maintained or mis-adjusted
equipment may result in improperly cured
material. Equipment must be carefully maintained
and adjusted according to instructions in the
manual.
• To prevent inhalation of isocyanate mists, vapors,
and atomized particulates, everyone in the work
area must wear appropriate respiratory protection.
Always wear a properly fitting respirator, which
may include a supplied-air respirator. Ventilate the
work area according to instructions in the fluid
manufacturer’s SDSs.
• Avoid all skin contact with isocyanates. Everyone
in the work area must wear chemically
impermeable gloves, protective clothing and foot
coverings as recommended by the fluid
manufacturer and local regulatory authority. Follow
all fluid manufacturer recommendations, including
those regarding handling of contaminated
clothing. After spraying, wash hands and face
before eating or drinking.
Cross-contamination can result in cured material in
fluid lines which could cause serious injury or damage
equipment. To prevent cross-contamination:
• Never interchange component A and component B
wetted parts.
• Never use solvent on one side if it has been
contaminated from the other side.
NOTICE
Partially cured ISO will reduce performance and the life
of all wetted parts.
• Always use a sealed container with a desiccant
dryer in the vent, or a nitrogen atmosphere. Never
store ISO in an open container.
• Keep the ISO pump wet cup or reservoir (if
installed) filled with appropriate lubricant. The
lubricant creates a barrier between the ISO and the
atmosphere.
• Use only moisture-proof hoses compatible with
ISO.
• Never use reclaimed solvents, which may contain
moisture. Always keep solvent containers closed
when not in use.
• Always lubricate threaded parts with an
appropriate lubricant when reassembling.

Important Iscocyanate (ISO) Information
8 3A7284B
Changing Materials
A (Red) and B (Blue)
Components
NOTE: Material suppliers can vary in how they refer to
plural component materials.
Be aware that when standing in front of the manifold on
proportioner:
• Component A (Red) is on the left side.
• Component B (Blue) is on the right side.
For all machines:
• The A (Red) side is intended for ISO, hardeners,
and catalysts.
• If one of the materials being used is moisture-
sensitive, that material should always be in the A
(Red) side.
• The B (Blue) side is intended for polyols, resins, and
bases.
NOTE: For machines with material volume ratios other
than 1:1, the higher volume side is typically at the B
(Blue) side.
NOTICE
Changing the material types used in your equipment
requires special attention to avoid equipment damage
and downtime.
• When changing materials, flush the equipment
multiple times to ensure it is thoroughly clean.
• Always clean the fluid inlet strainers after flushing.
• Check with your material manufacturer for
chemical compatibility.
• When changing between epoxies and urethanes
or polyureas, disassemble and clean all fluid
components and change hoses. Epoxies often
have amines on the B (hardener) side. Polyureas
often have amines on the B (resin) side.

Overview
3A7284B 9
Overview
This plural component meter, mix, and dispense device
accurately meters liquid and semi-paste materials.
The machine is ideal for a two-component application
requiring very small and precisely mixed shots.
The ratio of the pneumatic cylinder area to pump shaft
area provides the adjustable pressure intensification
needed to move the separate liquids through the mixer
with a flow rate suitable for production requirements.
The complete system is enclosed. Mixing of the two
materials takes place only in the mixer at the final stage
of metering valve operation. See Sequence of
Operation on page 18.
Grounding
Metering valve: attach the ground wire from the
grounding lug (C) to a true earth ground. See Motor
Driven PD44 Metering Valve on page 10.
Fluid hoses: use only electrically conductive hoses with
a maximum of 500 ft. (150 m) combined hose length to
ensure grounding continuity. Check electrical resistance
of hoses. If total resistance to ground exceeds 29
megohms, replace hose immediately.
Fluid supply container: follow local code.
Feed System components: attach ground wire from
grounding lug to true earth ground. See the pump
manual for grounding points. See Related Manuals on
page 3.
Solvent pails used when flushing: follow local code.
Use only conductive metal pails, placed on a grounded
surface. Do not place the pail on a nonconductive
surface, such as paper or cardboard, which interrupts
grounding continuity.
To maintain grounding continuity when flushing or
relieving pressure: hold metal part of the dispense
valve firmly to the side of a grounded metal pail, then
trigger the gun/valve.
The equipment must be grounded to reduce the risk
of static sparking. Static sparking can cause fumes to
ignite or explode. Grounding provides an escape wire
for the electric current.

Component Identification
10 3A7284B
Component Identification
Motor Driven PD44 Metering Valve
FIG. 1: PD44 Metering Valve Component Identification
P
E
J
F
C
P
K
DD
B
A
R
L
M
SN
Key:
A A Material Inlet (1/4 NPT)
B B Material Inlet (1/4 NPT)
C Grounding Lug
D Spool Assemblies
E Metering Rods
F Retaining Block
J Dispense Air Inlet
K Reload Air Inlet
L Outlet Nose
M Over-travel Proximity Switch
N Home Proximity Switch
P Spool Valve Proximity Switch
R Motor (not included)
S Main Air Inlet/Control
Solenoid (on far side of valve
as shown)
M