Model FF-2500 Proportioning Unit
20
25942-1, Issue 4
Air Purge
Before using the equipment, it is necessary to purge the entire chemical system of air and
mineral oil left over from the functional testing of the equipment at the factory.
To purge the machine proceed as follows:
1. Turn on the main air supply.
2. With the resin and isocyanate transfer pumps in their respective drums and the A
and R-inlet supply valves closed, pressurize the transfer pumps. Check for chemical
leaks.
3. Open the A and R-inlet supply valves.
4. Switch ON the main switch. (The white pilot light should be ON.)
5. Adjust both air pressure regulators to zero. (Fully counterclockwise).
6. Set the pump switch to NORMAL.
7. Adjust both the air pressure regulators
clockwise until the pumps begin to move
(approximately 15-psi air pressure). When
the pumps reach the top of their stroke, turn
the pump switch to OFF. This will allow
access to the pump lubricant cup on the
isocyanate pump. Fill the cup to about 1/4-
inch from the top with Gusmer pump
lubricant
(see Figure 13).
8. Hold the coupling block with the A- and R-
ports over separate containers and open
both manual valves.
Figure 13. Pump Lubricant
Cup
9. Set the pump switch to NORMAL. If necessary, gradually adjust both the air
pressure regulators clockwise to start the proportioning pumps moving slowly.
Please dispose of waste chemicals
in accordance with applicable
local, state, and federal codes.
10. Allow material to flow out of the coupling block until all spitting of air stops and all
traces of residual material have disappeared. Close the manual valves and flush any
residual chemical from the outside of the coupling block (see Gun Operating
Manual).
11. Slowly increase the air pressure and check all fittings for signs of hydraulic and
chemical leakage. Tighten fittings as required.
12. Turn OFF the pump switch.
13. Mount the gun to the coupling block. (See the Gun Operating Manual.)
IMPORTANT: After the proportioning system has been brought up to operating
pressure and all hose connections are tight and free of leaks, wrap together the hoses
and electrical wires around the area of the rubber isolators with a liberal amount of duct
tape to form a compact bundle. If a scuff jacket is being used, pull it over the bundle and
secure with tape.
