Graco A-25 important safety instructions Spray Adjustments, Sb Sa

Page 25

9.Slowly increase the air regulator setting until the approximate stall (static) pressure is achieved on fluid gauges (GA) and (GB).

SB SA

GA

GB

ti8441a

10.Check fluid pressure gauges (GA, GB) to ensure proper pressure balance. If imbalanced, reduce pressure of higher component by slightly turning PRESSURE RELIEF/SPRAY valve for that component toward PRESSURE RELIEF/CIRCULATION, until gauges show balanced pressures.

NOTE: Ensure relief tubes are in waste containers.

11. Open gun fluid inlet valves A and B.

ti2414a

12. Disengage gun piston safety lock.

ti2410a

13.Test spray onto cardboard. Adjust the air regulator to get the minimum fluid pressure that results in a good spray pattern.

NOTE: Pumps have fluid to air ratio of 25 to 1. Feed pumps add 2X feed pressure boost to outlet pressure (on the up stroke only). For best results, use regulators on feed pumps to limit inlet feed pressure to approxi- mately 100 psi (0.7 MPA, 7 bar).

14.Check A and B fluid pressure gauges (GA, GB) to ensure proper pressure balance between A and B.

15.Equipment is ready to spray.

Spraying

Spray Adjustments

Flow rate, atomization, and amount of overspray are affected by four variables.

Fluid pressure setting. Too little pressure results in an uneven pattern, coarse droplet size, low flow, and poor mixing. Too much pressure results in excessive overspray, high flow rates, difficult control, and excessive wear.

Fluid temperature. Effects are similar to when fluid pressure setting is too high or too low.

Mix chamber size. Choice of mix chamber is based on desired flow rate within machine capability and fluid viscosity.

Cleanoff air adjustment. Too little cleanoff air results in droplets building up on the front of the nozzle, and no pattern containment to control over- spray. Too much cleanoff air results in air-assisted atomization and excessive overspray.

3A1569B

25

Image 25
Contents Operation Contents Systems Proportioner ModelsRelated Manuals Proportioner Heated Hose GunElectric Shock Hazard Fire and Explosion Hazard Equipment Misuse Hazard Important Two-Component Material Information Changing Materials Typical Installation, without Circulation Key for FIG Typical Installation, without CirculationTypical Installation, with Circulation Typical Installation, with CirculationComponent Identification IG Typical InstallationMain Air Filter Filters system air supply See Tempera- ture Controls and Indicators Temperature Controls and IndicatorsControl Panel Size Component Main Power SwitchDetermine Power Source SetupLocate Reactor A-25 Electrical Requirements Step One Connect Electrical Cord Configure to Supply PowerHeater Jumpers WattsTerminal Blocks Ground System Fluid Supply Connections Iso Pump Lubrication System SetupAir Supply Connection Recirculation / Pressure Relief Lines Install Fluid Temperature Sensor FTSConnect Heated Hose Fusion AP Gun shown Load Fluid with Feed Pumps Initial StartupPressure Check Hose Manual current control mode only Set TemperaturesSupply Wet-Cups with Throat Seal Liquid Closed SprayingSB SA Spray AdjustmentsPark Pressure Relief ProcedureShutdown Open CloseFlushing Operation Daily Start-up ProcedureOpen gun fluid manifold valves a and B Circulation Through Reactor Fluid CirculationCirculation Kit CK Part Gun Manual Circulation Through Gun ManifoldRun Mode DataTrak Controls and IndicatorsSetup Mode Run Mode Setup ModeSee DataTrak Diagnostic Codes DataTrak OperationMaintenance Temperature Control Diagnostic Codes Diagnostic CodesDataTrak Diagnostic Codes Symbol Code Code Name Diagnosis CauseWith Wheels Without Wheels Dimension In. mm DimensionsCategory Data Technical DataGraco Information Graco Standard Warranty
Related manuals
Manual 56 pages 23.25 Kb