Empire Abrasive Equipment Company
Check the vent in the
blast air valve diaphragm
cover spring retainer nut
for leaking air.
Confirms that the blast air valve
diaphragm has failed. Repair or
replace the air valve.
Improper media.
See section
4.1 Media Selection and
Use.
Step 8:
There are media
problems.
Improper media flow.
See section
3.0 Equipment
Adjustment.
Problem:
There is excessive delay between stepping on the foot treadle and the blast
activation. Normally this delay should be between ½ and 1 second for suction systems
and 1 to 2 seconds for pressure systems.
Probable Cause
Test
Remedy
Step 1:
Restricted flow in
control lines.
Disconnect the control
tubing at the pipe string
air valve. Install a
pressure gauge on the
open end of the tubing
and step on the foot
treadle. The gauge slowly
reaches the full line
(supply) pressure.
Check for kinks or crimps in the
control air lines.
Trace leaks by moving the gauge up
stream until the full line pressure is
observed.
Step 2:
Leak in control
lines.
Disconnect the control
tubing at the pipe string
air valve. Install a
pressure gauge on the
open end of the tubing
and step on the foot
treadle. The gauge never
reaches the full line
(supply) pressure.
For pressure systems only, if the
gauge at the exhaust valve
pressurizes rapidly to full line
pressure, the exhaust valve has a leak
or a ruptured diaphragm.
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