Graco 311321M User Manual

Operation, Parts, Service, Repair

GX-7A™, GX-7® DI, and GX-7 400

311321M

Spray Guns

For use with non-flammable polyurethane foams, two-component coating systems (polyureas), and some two-component epoxy systems. For professional use only.

See page 2 for model information.

3500 psi (24 MPa, 240 bar) Maximum Working Pressure

Important Safety Instructions

Read all warnings and instructions in this manual. Save these instructions.

GX-7A

GX-7 400

GX-7 DI

Models

Contents

Models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

Warnings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Overall View . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Centerline Components . . . . . . . . . . . . . . . . . . . 8

Mixing Module . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Operation Basics . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Isocyanate Hazard . . . . . . . . . . . . . . . . . . . . . . 11

Keep A and B Components Separate . . . . . . . . 11

Grounding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Safety Position . . . . . . . . . . . . . . . . . . . . . . . . . 11

Air Hose Connection . . . . . . . . . . . . . . . . . . . . . 12

Coupling Block . . . . . . . . . . . . . . . . . . . . . . . . . 13

Air Inlet Configuration . . . . . . . . . . . . . . . . . . . . 14

Mixing Module and PCD Installation . . . . . . . . . 15

Valving Rod Adjustment . . . . . . . . . . . . . . . . . . 16

Initial Set Up . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

Daily Start-up . . . . . . . . . . . . . . . . . . . . . . . . . . 18

Daily Shutdown . . . . . . . . . . . . . . . . . . . . . . . . . 18

Pressure Relief Procedure . . . . . . . . . . . . . . . . . . 19

Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

Gun Service Kits . . . . . . . . . . . . . . . . . . . . . . . . 20

Clean Spray Gun Procedure . . . . . . . . . . . . . . . 20

Flush Gun . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

Repair . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

Service Screen Screw . . . . . . . . . . . . . . . . . . . . 22

Remove Centerline Components . . . . . . . . . . . 22

Install Centerline Components . . . . . . . . . . . . . 24

Replace End Cap and Air Piston Assembly . . . 25

Replace Trigger Valve O-Rings . . . . . . . . . . . . . 26

Clean Mixing Module . . . . . . . . . . . . . . . . . . . . . 27

Install Mixing Module . . . . . . . . . . . . . . . . . . . . . 28

Clean Pattern Control Disc . . . . . . . . . . . . . . . . 29

Parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

GX-7A Model Final Assembly . . . . . . . . . . . . . . 30

GX-7 DI Model Final Assembly (295541) . . . . . 32

GX-7 400 Model Final Assembly (295540) . . . . 34

GX-7A Model Handle Assembly (24K734) . . . . 36

GX-7 DI Model Handle Assembly (295809) . . . 38 GX-7 400 Model Handle Assembly (24K733) . . 40

Coupling Block Assembly (295383) . . . . . . . . . . 42

Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43

GX-7A Mix Module Kit . . . . . . . . . . . . . . . . . . . . 43

Set-Up Chart for GX-7A Model . . . . . . . . . . . . . 44

GX-7 400 Mix Module Kit . . . . . . . . . . . . . . . . . . 45

Set-up Chart for GX-7 400 Model . . . . . . . . . . . 46

GX-7 DI Model Specifications . . . . . . . . . . . . . . 47

Tip Kits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48

Tool Kit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48

Technical Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49

Graco Standard Warranty . . . . . . . . . . . . . . . . . . . 50

Graco Information . . . . . . . . . . . . . . . . . . . . . . . . . 50

Models

Includes:

Part No. Description

295540 GX-7 400 296859 (451)

295541 GX-7 DI - 4/213 296901 (4)

295542 GX-7A - 1/90 296909 (1)

295543 GX-7A - 10/210 296906 (10)

295544 GX-7A - 3/70 296226 (3)

295545 GX-7A - 5/70 296923 (5)

2 311321M

Mix Module Tip

296853 (212)

296706 (213)

296712 (90)

296704 (210)

296710 (70)

Warnings

The following general warnings are for the setup, use, grounding, maintenance, and repair of this equipment. Additional, more specific warnings may be found throughout the body of this manual where applicable. Symbols appearing in the body of the manual refer to these general warnings.

When these symbols appear throughout the manual, refer back to these pages for a description of the specific hazard.

WARNING

PERSONAL PROTECTIVE EQUIPMENT

You must wear appropriate protective equipment when operating, servicing, or when in the operating area of the equipment to help protect you from serious injury, including eye injury, inhalation of toxic fumes, burns, and hearing loss. This equipment includes but is not limited to:

• Protective eyewear

• Clothing and respirator as recommended by the fluid and solvent manufacturer

•Gloves

• Hearing protection

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 MSDS’s to know the specific hazards of the fluids you are using.

• Store hazardous fluid in approved containers, and dispose of it according to applicable guidelines.

SKIN INJECTION HAZARD

High-pressure fluid from gun, 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 gun at anyone or at any part of the body.

• Do not put your hand over the spray tip.

• Do not stop or deflect leaks with your hand, body, glove, or rag.

• Do not spray without tip guard and trigger guard installed.

• Engage trigger lock when not spraying.

•Follow Pressure Relief Procedure in this manual, when you stop spraying and before cleaning, checking, or servicing equipment.

311321M 3

Warnings

WARNING

FIRE AND EXPLOSION HAZARD

Flammable fumes, such as solvent and paint fumes, in work area can ignite or explode. 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 arc).

• 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.

• Ground all equipment in the work area. See Grounding instructions.

• Use only grounded hoses.

• Hold gun firmly to side of grounded pail when triggering into pail.

• If there is static sparking or you feel a shock, stop operation immediately. Do not use equipment until you identify and correct the problem.

• Keep a 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 Data in all equipment manuals.

• Use fluids and solvents that are compatible with equipment wetted parts. See Technical Data in all equipment manuals. Read fluid and solvent manufacturer’s warnings. For complete information about your material, request MSDS forms from distributor or retailer.

• Check equipment daily. Repair or replace worn or damaged parts immediately with genuine Graco/Gusmer replacement parts only.

• Do not alter or modify equipment.

• Use equipment only for its intended purpose. Call your Graco/Gusmer 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.

PRESSURIZED EQUIPMENT HAZARD

Fluid from the gun/dispense valve, leaks, or ruptured components can splash in the eyes or on skin and cause serious injury.

•Follow Pressure Relief Procedure in this manual, when you stop spraying and before cleaning, checking, or servicing equipment.

• Tighten all fluid connections before operating the equipment.

• Check hoses, tubes, and couplings daily. Replace worn or damaged parts immediately.

4 311321M

Warnings

WARNING

PRESSURIZED ALUMINUM PARTS HAZARD

Do not use 1,1,1-trichloroethane, methylene chloride, other halogenated hydrocarbon solvents or fluids containing such solvents in pressurized aluminum equipment. Such use can cause serious chemical reaction and equipment rupture, and result in death, serious injury, and property damage.

311321M 5

Overall View

2 !

Overall View

Model GX-7A

Gun Block

Manual Valves

FIG. 1: GX-7A Overall View

Forward Stop Locknut

Valving Rod Rear Stop

Air Cap Adjustment Valve

Valving Rod Forward Stop

Rear Packing Nut

Trigger

Model GX-7 DI

. 2: GX-7 DI Overall View

6 311321M

Overall View

Model GX-7 400

Gun Block

Trigger

FIG. 3: GX-7 400 Overall View

Forward Stop Locknut

Valving Rod Rear Stop

Air Cap Valve

Valving Rod

Forward Stop

Rear Packing Nut

311321M 7

Overall View

Centerline Components

Model GX-7A

Valving Rod

Rear Packing

Packing

Nut

Rear Packing Retainer

Screen

Screw Seal

Check Valve Assembly

R-Screen Screw

FIG. 4: GX-7A Centerline Components

Gun Block

Coupling Block Gasket

A-Screen Screw

Check Valve

Front Packing

Pattern Control Disc (PCD)

Mixing Module

PCD Retainer

Screen Screw Seal

Screen

PCD Body

O-ring

Air Cap

Model GX-7 DI

Check Valve

Mixing Module

Mixing Module Retainer

PCD Retainer

Air Cap

. 5: GX-7 DI Centerline Components

R-Screen Screw

Screen

Gun Block

Pattern Control Disc (PCD)

Rear Seal Gland

Rear Packing

Coupling Block Gasket

Coupling Block Mounting Screw

Rear Seal Retainer Assembly

Check Valve

Screen

A-Screen Screw

8 311321M

Model GX-7 400

Overall View

R-Screen Screw

Screen Screw Seal

Check Valve

Mixing Module

Pattern Control

Disc (PCD)

Air Cap

Spring

PCD Retainer

Coupling Block Gasket

Coupling Block Mounting Screw

Rear Packing

Retainer

Gun Block

Rear Packing

Valving Rod

Rear Seal Retainer

Check Valve

Screen

Screen Screw Seal

A-Screen Screw

FIG. 6: GX-7 400 Centerline Components

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Overall View

Mixing Module

All gun models employ the concept of impingement mixing through the use of a single-part MIXING MODULE. This system is cleaned by a mechanical self-cleaning process, eliminating the need for solvent or air purging between dispenses.

Valving Rod

The gun can be assembled with two styles of mixing components; their selection is dependent upon the type of system sprayed. The Set-Up Charts on pages 44 and 46 show several of the more common sets of these configurations.

The Mixing Module, in combination with a Pattern Control Disc (PCD), produce a thoroughly mixed chemical and reliable spray patterns. The module can be set up to spray at its maximum rated output. Additionally, by changing to a smaller PCD the module can spray at the low outputs and pressures that are required for detail work.

PCD (round or flat)

Valving Rod

Mixing Module (round or flat)

PCD (round or flat)

. 8: GX-7 400 Mixing Module

Mixing Module (round or flat)

PCD (round or flat)

. 9: GX-7 DI Mixing Module

Valving Rod

Mixing Module (round or flat)

FIG. 7: GX-7A Mixing Module

10 311321M

Operation Basics

To prevent accidental gun operation, always disconnect air supply before servicing gun or anytime gun is not in use.

Isocyanate Hazard

Spraying materials containing isocyanates creates potentially harmful mists, vapors, and atomized particulates.

Read material manufacturer’s warnings and material MSDS to know specific hazards and precautions related to isocyanates.

Prevent inhalation of isocyanate mists, vapors, and atomized particulates by providing sufficient ventilation in the work area. If sufficient ventilation is not available, a supplied-air respirator is required for everyone in the work area.

To prevent contact with isocyanates, appropriate personal protective equipment, including chemically impermeable gloves, boots, aprons, and goggles, is also required for everyone in the work area.

Operation Basics

Grounding

Check your local electrical code and proportioner manual for detailed grounding instructions.

Ground the spray gun through connection to a Graco-approved grounded fluid supply hose.

Safety Position

The guns have a two-position valving rod rear stop. The SERVICE position allows for minimal rearward travel of valving rod but will not allow chemical to discharge. The OPEN position allows full rearward travel of valving rod and permits gun to dispense. Whenever gun is not spraying, set to SERVICE position.

Engage Safety Stop

To engage safety stop, push in and turn safety stop clockwise to place gun in CLOSED (SERVICE) position.

Keep A and B Components Separate

CLOSED (SERVICE)

CAUTION

To prevent cross-contamination of the gun’s wetted parts, do not interchange A component (isocyanate) and B component (resin) parts. The gun is shipped with the A side on the left.

311321M 11

FIG. 10: Safety Stop - Closed

When not spraying in safety position.

Operation Basics

Disengage Safety Stop

To disengage safety stop, push in and turn safety stop counterclockwise to place gun in OPEN position (red band is exposed).

Red Band

OPEN

Red band exposed when spraying.

FIG. 11: Safety Stop - Open

Close Manual Valves

Air Hose Connection

Connect Air Hoses

Pull back sleeve of female fitting, insert male fitting and slide sleeve forward to secure connection.

Disconnect Air Hoses

Pull back sleeve of female fitting and pull out male fitting.

Pull Sleeve

Closing manual valves prevents chemicals in heated hoses from entering gun. For your own safety, close manuals valves before servicing gun.

Manual Valves rotate clockwise to close.

FIG. 12: Close Manual Valves

FIG. 13: Disconnect Air Hose

12 311321M

Operation Basics

Coupling Block

Chemical hoses are joined to gun block by coupling block to ease installation and removal of gun.

Manual Valves

Two manual valves located on coupling block control flow of each chemical component to gun.

Triggering gun with manual valves closed may cause crossover if any residual chemical remains in gun ports.

Never open manual valve unless coupling block is secured to gun or unless you point gun into waste container.

Close Manual Valves

Use 5/16 in. nut driver to turn manual valve fully clockwise.

CAUTION

To prevent accidental gun operation, always set safety stop to CLOSED (SERVICE), close both manual valves, and disconnect air supply.

Installation and Removal

To prevent release of pressurized chemicals, close both manual valves before removing coupling block.

Install Coupling Block

1. Replace nicked, damaged, or worn coupling block gaskets.

Open Manual Valves

Use 5/16 in. nut driver to turn manual valve counterclockwise three full turns.

Coupling Block

Manual Valves

FIG. 14: Open Manual Valves

2. With gaskets in place, fit coupling block to gun block.

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Operation Basics

3. Insert coupling block mounting screw and use 5/16 in. nut driver to tighten to gun block.

Coupling Block

Gaskets

Coupling Block Mounting Screw

Optional Configuration

Refer to page 42. If bottom-mount hose connection is desired, alternate swivel fitting (2 and 3) with pipe plugs (1). Use pipe thread sealant. Do not cross-over which side each fitting is on.

Air Inlet Configuration

There are two configurations for the air inlet. In the standard configuration the air inlet is at the base of the handle, and in the alternate configuration the air inlet is at the rear of the gun.

Pipe Plug

FIG. 15: Install Coupling Block

Remove Coupling Block

1. Set safety stop to CLOSED (SERVICE).

2. Disconnect air hose.

3. Close both manual valves.

4. Remove coupling block mounting screw.

5. Separate coupling block from gun.

6. Wipe mating surfaces of gun block and coupling block to remove residual chemical.

7. Cover exposed openings with grease.

Optional Pipe Nipple

Pipe Nipple

FIG. 16: Air Inlet Configuration

To change to alternate configuration,

1. Remove pipe nipple.

2. Remove pipe plug from rear of gun.

3. Install pipe plug in location previously occupied by pipe nipple.

4. Install pipe nipple in location previously occupied by pipe plug.

14 311321M

Operation Basics

Mixing Module and PCD Installation

1. Install mixing module:

a. Disconnect gun from coupling block.

b. Connect air supply to gun.

c. Set safety stop to OPEN.

d. Hold down trigger and place module

over tip of valving rod.

e. Align keying pin with hole in gun block

and push in firmly (GX-7 DI model only).

f. Install front packing into module retainer

(GX-7 model only).

f. Use wrench to loosen piston locknut.

Turn valving rod rearward as far as it will turn.

g. Place and orient PCD over mixing mod-

ule retainer.

h. Install PCD retainer and hand tighten

(GX-7 DI model only).

i. Install PCD retainer and wrench tighten

(GX-7 model only).

3. Adjust valving rod. See procedure for appropriate gun model.

4. Set safety stop to OPEN position.

5. Check adjustment of valving rod:

g. Install module retainer, hand tight.

Release trigger.

h. Use wrench to strongly tighten module

retainer (250 in.-lbs.). GX-7 DI model only: use wrench to tighten module retainer (150 in.-lbs.). DO NOT OVERTIGHTEN.

2. Install PCD:

a. Disconnect air supply from gun.

b. Loosen forward stop screw (GX-7

model only).

c. Turn forward stop nut clockwise (as

viewed from front of gun) 1-2 turns (GX-7 model only).

a. With air supply connected, hold down

gun trigger and loosen PCD retainer. Release trigger.

b. Hand tighten PCD retainer.

c. While maintaining tightening torque,

trigger gun. Retainer should rotate approximately 1/10 of turn.

d. Release trigger.

d. Slightly loosen rear seal retainer

assembly.

e. Remove safety stop.

311321M 15

+ 35 hidden pages