Operation
6.
Turn the machine around by first closing the feed valve. Then turn the machine to
the right and guide it in an arc to get back to the last blasted path. Repeat this in
order to complete the surface. Move away from the filter towards the open surface.
7. Move the dust collector to the surface already blasted and finished the area where
the filter was located before.
THE BLAST PATTERN
Abrasive scatter is restricted to an angle of about 55°. The position of the window in the
control cage determines the direction and hot zone of the blast pattern.
Correct adjustment of the control cage and thus of the blast pattern is the most important
factor for optimum working with this machine. Incorrect adjustment of the control cage will
result in very high wear and premature blasting through of the liners in the blast wheel
housing, as well as reduced blasting performance and a possible loss of the rebound
energy of the abrasive.
After each blast wheel repair work, switch on the blast wheel motor for a short period
(without feeding abrasive) in order to find out whether the rotating parts turn freely and
without vibration. After that, the blast cleaning procedures can be continued.
PATTERN AND CONTROL CAGE ADJUSTMENTS
In order to get a uniform blast pattern on the surfaces to be treated, the correct adjust
-
ment of the blast pattern is most important. Incorrect adjustment of the blast pattern
results in:
•
Uneven cleaning (shadows on the right or left hand side).
•
Extreme wear on wheel kit and liners.
Factors That Affect the Blast Pattern
•
The rotation direction of blast wheel must correspond to the arrow indicating the
turning direction on the housing.
•
With increased wear of the wheel kit, the blast pattern will change.
•
Every change of abrasive requires the blast pattern to be set or to be re-adjusted.
•
The position of the lateral window in the control cage determines where the abra
-
sive is fed on the blast wheel blades. After changing the wheel kit, the control cage
must be checked and re-adjusted.
Adjusting the Control Cage (Figure 14)
The adjustment is done by slackening the cage clamps (H), and turning the control cage
(Z) into a pre-setting position. The cast grooves or notches on the control cage show the
position of the control cage opening. The feed spout remains in its former position; the
control cage opening is approximately opposite to the throwing angle.
The adjustment can be carried out with the following steps (Figure 15):
1.
Determine the upper (OK) and lower (UK) window edges of the control cage.
2.
Set the upper window edge of the control cage to the angle that would be 11:00
on a dial.
3.
Place the cage clamps (3) and fix them with nuts (2).
4.
Place the feed spout (4) onto the control cage.
Test blast for 45 seconds at full amperage without moving the machine on a 3/16-5/16”
(5-8 mm) steel plate. Move the machine from the blast zone when finished and inspect
12
FIG. 14
FIG. 15
FIG. 16
FIG. 17