Graco Dispensit 792-20 [6/14] Periodic maintenance

PERIODIC MAINTENANCE

MATERIAL HOSE RENEWAL

Material hose life is difficult to predict due to its dependence on the cycles, speed, downtime and material

dispensed. A common sign of a worn material hose is a reduction in shot volume. Inspect the material

hose periodically and renew or replace as necessary.

Depending on the application layout it may be possible to renew the pinch area of the material hose by

pulling it through the valve and trimming off the worn area.

1. Depressurize the material reservoir, and remove/disconnect it.

2. Pressurize the Pinch-off Piston (11). This is the purge mode. The Material Hose (16) will now be

completely free of compression.

3. If your valve has a Hose Adapter (19), disconnect downstream fittings as required so that the Hose

Adapter can be turned freely.

4. Remove the Hose Adapter (19) or Needle Assembly (18) from the Bottom Tube Adapter (17).

5. Pull the Material Hose (16) down through the valve to expose the worn pinch area on the Material

Hose. Cut the Material Hose squarely above the worn pinch area and flush with the end of the the

Bottom Tube Adapter (17).

6. Insert the steel end of the Hose Adapter (19) or Needle Assembly (18) into the end of the Material

Hose (16) and tighten onto the Bottom Tube Adapter (17). Check all connections.

7. If your valve has a Hose Adapter (19), connect downstream fittings to it.

8. Connect the material reservoir and pressurize it.

9. Perform the Wet System Checkout and return to operation.