User's Manual

ManualsBrandsGraco ManualsSprayersGraco 308225K - Bulldog Hydra-Cat Fixed Ratio Proportioning Pumps

308225 21

Operation

Startup

WARNING

INJECTION HAZARD

To reduce the risk of serious injury,

follow the Pressure Relief Procedure

on page 19 whenever you are instructed

to relieve the pressure.

Never exceed the maximum air and fluid working

pressure of the lowest rated component in your

system. See Equipment Misuse Hazard, page 4.

1. Install full containers of resin and hardener at the

feed pumps.

2. To prime the system, follow Steps 2 to 11 of the

Flushing procedure on page 17.

3. Turn on the heaters, if used, and allow them to

warm up for 10 minutes.

4. Open the feed pump air valves (A1,A2). Adjust the

air regulators (E1,E2) just enough to start the

pumps operating slowly.

5. Open the proportioning pump air valve (A3) and

slowly open the regulator (E3) to start the propor-

tioning pump.

6. Open the mixer manifold (N) and trigger the

dispense valve (S).

7. Set the air pressure to the feed pumps at 88 psi

(605 kPa, 6 bar) or 25% of proportional pressure at

the fluid outlets, whichever is less. Use the gauges

(J1) to monitor this pressure. Higher pressures

may prevent the proportioning pump inlet ball

checks from setting properly.

8. Set the air pressure to the proportioning pump (H)

to obtain the required fluid pressure. Refer to the

proportioning pump chart on page 6 for the fluid

to air pressure.

9. While triggering the dispensing valve, check the

fluid outlet pressure gauges (J2) and make note of

the pressures indicated. Check the gauges

frequently during operation. These notes will help

to analyze any problems that may occur since a

change in displacement pump performance will be

indicated by a change in pressure gauge readings.

NOTE: A pressure drop does occur during pump

stroke changeover.

NOTE: Flush the mixer manifold frequently during the

day’s operation. Follow Step 11 on page 17.

02913

Fig. 17

KEY

A Bleed-type master air valve

A1 Hardener feed pump

A2 Resin feed pump

A3 Proportioning pump

E Pump air regulator

E1 Hardener feed pump

E2 Resin feed pump

E3 Proportioning pump

J Fluid pressure gauge

J1 Proportioning pump intake

J2 Proportioning pump outlet

H Proportioning pump

N Mixer manifold

S Dispensing valve

V Fluid strainer