CHERNE Test-Ball - Proper Plug Removal Procedures

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13. PROPER PNEUMATIC PLUG REMOVAL.
A. RELEASE ALL RESTRAINED MEDIA (back pressure) from a
pneumatic plug before deatiing the plug.
PLUGS PROPERLY BLOCKED OR SUPPORTED BY BRACING MAY
BE DEFLATED TO RELEASE THE MEDIA RESTRAINED BY THE
PLUG (BACK PRESSURE).
Gradual plug deation can control the rate
of media discharge. Use extreme caution to ensure that such bracing is
properly designed to withstand the full force of the plug and any restrained
media. Ensure that any media released does not result in injury or property
damage.
SOME CHERNE PRODUCTS ARE DESIGNED TO SAFELY RELEASE
BACK PRESSURE WITHOUT THE USE OF BRACING.
This includes
MS2® Long Test-Ball® plugs and Clean-Seal® plugs which are simply
deated to release back pressure. Other plugs such as most sizes of
pillow type Muni-Ball® and Test-Ball® plugs have tether attachment points
of sufcient strength to allow attachment of an anchor cable that can
withstand full rated back pressure. Call Cherne toll free at 1-800-843-7584
for specic recommendations.
A HOSE AND SHUT OFF VALVE MAY BE ATTACHED TO THE BY-PASS
OF A MUNI-BALL® PLUG.
The valve is opened from outside the Danger
Zone to release back pressure. The back pressure may be released by
gravity ow or the hose may be attached to the inlet of a water pump.
THE SUCTION HOSE OF A PUMP MAY BE INSERTED BEHIND A PLUG.
Some applications allow direct access to the restrained media. Back
pressure is relieved by activating the pump to remove the media.
THE BY-PASS OF A MUNI-BALL® PLUG MAY BE TEMPORARILY
BLOCKED USING A SMALL PNEUMATIC PLUG.
The small plug,
connected to an ination extension hose, is deated from outside the
Danger Zone to allow release of back pressure, air or water, through the
Muni-Ball® bypass. NOTE: Damage to the small plug and extension hose
may occur as the plug is ejected from the bypass area. Inspect the plug
and hose carefully before attempting further use.
WATER
WATER
ZONE
DANGER
ZONE
DANGER
WATER MAY BE PUMPED FROM
BEHIND PLUG TO RELEASE
BACK PRESSURE
CONSULT A REGISTERED ENGINEER
ON BRACING CONSTRUCTION
PLUGS PROPERLY
BRACED MAY BE
DEFLATED TO
RELEASE BACK
PRESSURE
BRACING