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Page 11
GENERAL OPERATION
PRIMARY COMPONENTS/HOW #3390 SHOTBLAST WORKS
The shot hopper is the area of the machine where steel shot is initially loaded into the machine. A shot
lever is attached to the handle of the machine and when the lever is squeezed a cable connected to the
lever opens the shot valve. As the shot valve is opened, steel shot fall through the shot valve and passes
through the feed spout into the blast wheel. The blast wheel sits in a control cage. A 110 volt right angle
motor spins the blast wheel at a very high rate of speed. As the steel shot falls into the spinning blast
wheel it is thrown by the blast wheel through an opening in the control cage and down on to the floor
being cleaned. Due to high rate of speed at which the steel shot is traveling, the steel shot fractures the
concrete surface producing concrete dust. The shot rebounds, or bounces off of the floor and through a
combination of the the rebound effect and the use of a vacuum the steel shot and the concrete dust travel
through the blast housing. The steel shot is heavier than the concrete dust. Due to the difference in the
weight of the steel shot compared to the weight of the concrete dust the steel shot, through gravitation
force, is deposited back into the shot hopper and is recycled through the machine.
After traveling through the blast housing, the concrete dust is sucked into a duct hose which travels from
the blast housing to the dust collector. After traveling through the duct hose the concrete dust deposited
into the dust collector’s dust bin.
SAFETY START UP PROCEDURE
After performing the safety site assessment procedures bring the #3390 and dust collector to the work
area and perform the following procedures:
1. Inspect all electrical cords on the #3390 and dust collector for damage, tears or other signs of wear. If
electric cords are damaged do not attempt to perform blasting operations until cords have been repaired
or replaced.
2. Inspect the #3390 blast wheel, control cage, feed spouts, liners, seals, shot hopper, magnets and
other parts for wear. Replace worn parts where necessary.
3. Inspect the duct hose leading from the #3390 to the dust collector. Make sure hose is free of debris,
hose is not cracked and holes do not exist. If necessary replace hose.
4. Inspect the dust collector. Verify that dust bin is empty, filters are clean and clear of debris, motors
and fans are in working order. N
OTE
: T
HE
DUST
BIN
SHOULD
BE
EMPTIED
AT
THE
END
OF
EACH
JOB
.
5. Locate the #3390 adjacent to the dust collector and blast in straight lines moving away from the dust
collector. Blasting in straight lines will produce the most uniform results. Working away from the dust
collector will help prevent cords and hoses from becoming an obstruction. N
EVER
RUN
OVER
AN
ELECTRICAL
CORD
OR
A
HOSE
WITH
THE
#3390. R
UNNING
OVER
AND
ELECTRICAL
CORD
WITH
THE
#3390
CAN
RESULT
IN
SERIOUS
INJURY
TO
THE
OPERATOR
AND
DAMAGE
EQUIPMENT
.