Schmidt AmphiBlast 120 Operation And Maintenance Manual Download

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7.6.7. Turn the abrasive cutoff valve/switch (#62) to the “OFF” position. See Figure 5.3.

7.6.8. For initial startup the Thompson® Valve (#14) should only be partially open. Turn the

valve knob clockwise to completely close, then turn counterclockwise about four turns
to partially open. The best setting for the valve varies depending on abrasive type, blast
pressure, and nozzle size; therefore, it may take more than one adjustment to achieve the
desired air/abrasive mixture. Further adjustment can be made later as needed.

7.6.9. Close the blowdown ball valve (#4). The ball valve is closed when the handle is

perpendicular to the body (See Figure 7.1).

7.6.10. Slowly open the inlet ball valve (#3). This will pressurize the abrasive blaster and

supply air to the controls.

7.6.11. Slightly open the ball valve (#8) on bottom of the moisture trap (#7) to permit moisture

to continually drain during the blast operation. Once each day completely open the drain
valve to blow out all moisture and dirt particles.

7.6.12. Check the closure, manway, hoses, and piping for leaks while the blaster is pressurized.

Periodically check for leaks thereafter.

7.6.13. The following steps are for setting the water flow and wetting the blast hose (#10). The

water differential pressure gauge (#51) setting can only be seen while blasting, so it is
easier to perform this adjustment with two people.

Wet blasting greatly reduces air borne dust but the use of a respirator is still required
during blast operation.

All operators and personnel in the vicinity must wear OSHA

approved respiratory protection during the operation of this equipment See Sections 3.9,
3.10, and OSHA 29 CFR 1910.134

7.6.14. With one hand grip the blast hose assembly (#10) and with the other hand press in the

deadman safety button.

To begin blasting, aim the blast nozzle (#11) at the object to be

blasted, then firmly press down the deadman lever (#12). Air will flow into the blast
hose and out of the blast nozzle (#11).

Do Not aim the blast nozzle towards yourself or any person. A system malfunction or a
blocked blast nozzle that clears can trigger accidental start up resulting in injury to
personnel.

7.6.15. Turn the blast air pressure regulator knob (#44) to set the blast pressure gauge (#49) to

the desired blasting pressure. See Section 5.17 for procedure.

7.6.16. Adjust the water differential pressure regulator (#50) until the desired water flow is

achieved. See Section 5.21 for procedure. It could take approximately 10-15 seconds for
the blast hose (#10) to become wetted and for water to reach the blast nozzle (#11). This
delay only happens when starting with a dry blast hose (#10). Once the blast hose (#10)
has been wetted, the water will reach the blast nozzle (#11) instantly on subsequent
start-ups. Release the deadman lever (#12) to stop blasting.

7.6.17. Turn the abrasive cutoff valve or switch (#62) to the “ON” position. See Figure 5.3.

7.6.18. The following steps are for abrasive flow setting which may require several adjustments

and testing of the blast flow. It is recommended that testing of the blast be made on a
test piece so not to damage anything of value.