Graco 311320H important safety instructions Spray Pattern Adjustment, Point of Valving

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Spray Pattern Adjustment

Spray Pattern Adjustment

This adjustment may create a large mass “bun” of urethane foam. Very high tempera- tures created by chemical reaction inside a bun may not dissipate after outside surface has cooled. A large bun may continue to react for several hours after spraying until flash (burning) point of foam is reached. ALWAYS break buns into smaller pieces so heat can escape.

1.Check valving rod clearance in closed posi- tion. Rod should extend approximately 1/32 in. (1 mm) beyond tip of mixing chamber. If it does not, see Valving Rod Adjustment procedure, page 21.

1/32 in.

FIG. 10: Valving Rod (Closed Position)

2.Adjust valving rod travel to initial setting.

a.Loosen friction lock. Turn valving rod adjustment screw clockwise until it stops.

b.Turn valving rod adjustment screw 11 times counterclockwise.

3.Locate point of valving:

a.Aim gun at disposable target.

b.Dispense short (1 second) bursts toward target while simultaneously with- drawing valving rod adjustment screw

from retainer case by 1/4-turn incre- ments in counterclockwise direction.

c.Point of valving is reached when chemi- cal stream mists as shown in FIG. 11.

FIG. 11: Point of Valving

4.Adjust spray pattern. Note position of notch in hexhead of adjustment screw, then back screw out counterclockwise the number of turns specified in Table 1. Notice spray pat-

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311320H

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Contents Important Safety Instructions Model D Spray GunContents ModelsPersonal Protective Equipment Fire and Explosion Hazard Overall View Major ComponentsCenterline Components Centerline ComponentsIsocyanate Hazard Operation BasicsGrounding Keep a and B Components SeparateManual Valves Remove Coupling BlockValving Rod Adjustment Screw Air Hose ConnectionClean Felt Wiper Air Cap Adjustment ValveAdjust Felt Wiper Felt WiperInitial Set Up Valving Rod Closed PositionDaily Start-Up Daily ShutdownPressure Relief Procedure Spray Pattern Adjustment Point of ValvingTern opens as adjustment is made FIG Distance of Gun Chamber Minimum Maximum From Surface Valving Rod Adjustment for Standard Mixing ChambersTurns Out From Point Recommended Maintenance Gun Service KitsClean Spray Gun Procedure Filter Screen Removal and Service RepairClean Injection Slots Check ValvesValving Rod Adjustment Not RemoveCenterline Component Removal Mixing Chamber RemovalSleeve Removal Block Centerline Component Installation Chamber SeatingRepair Model D Spray Gun Assembly PartsModel D Spray Gun Assembly No. Part No. DescriptionAC chamber Standard Mixing Chambers Air Cylinder Assembly Part NumberCoupling Block Assembly Model311320H Technical Data Category DataGraco Standard Warranty Graco Information