Schwing SPB 28, Operation Manual

Page: 79 / 216

GENERAL RULE S
700+smgr.fm
PAGE 49
S AF ETY M AN U AL
• Be sure to open both valves on the blowout cap and verify all air has been
removed from the system before opening any clamps. Use a shovel or other
tool when opening clamps to assure a safe distance and avoid concrete blow-
ing in your eyes.
• The plug or go-devil must be thick enough to prevent compressed air flow
around the plug into the concrete.
• The pipeline must not be disassembled until it has been completely
relieved of air.
Be sure of this! (See Figure 65.)
• Be sure to open both valves on the blowout cap and verify all air has been
removed from the system before opening any clamps. Use a shovel or other
tool that will assure a safe distance from clamps to avoid concrete blowing in
your eyes.
• Do not use compressed air to blow out concrete delivery hose, single pipe
sections and short pipelines up to a length of 40 feet. Hoses will jump and
move unpredictably; short pipelines don’t have enough concrete to resist the
force of the air, causing it to discharge too quickly, like a cannon (Figure 66).
• When air pressure begins to drop rapidly, shut off the air supply from the
compressor, and immediately begin bleeding air out of the pipeline.
(The
drop in pressure signifies that the pipeline is almost empty of concrete.)
ball catcher
Water/air inlet
Air discharge
regulator valve
Air inlet
regulator valve
blowout head
catcher
&
cap
3
.eps
Figure 64
Ball catcher and
blowout head
e x plode2col.eps
sme
x
plode.eps
NO!
Figure 65
Never open a
pressurized pipeline