TDW PIG-SIG V, Operating And Maintenance Instructions Manual

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Section IV – Pipeline Under Pressure
Section IV
Overview
This section provides instructions for the installation
of the TDW PIG-SIG V Scraper Passage Indicator in
pipelines or pig traps while under pressure and where
there is product flow.
A THREAD-O-RING nipple may be installed over a
pre-cut opening in the pipe. As an option to installing
the nipple over a pre-cut opening, the opening may
be cut using a drilling machine with a 1-7/16-inch drill
after the nipple has been welded to the pipe. Once a
nipple has been welded to the pipe, it is
recommended that a drilling machine be used to cut
the opening in the pipe wall so that the nipple will act
as a guide and ensure proper alignment. The
opening through the pipe wall must be 1-7/16- to 1-
1/2-inch diameter, and the bore of the nipple must be
coaxial with the hole cut in the pipe to within 1/64-
inch. No part of a THREAD-O-RING nipple may
extend inside the pipe for reinforcement or for any
other purpose. If additional reinforcement is required,
THREAD-O-RING nipples can be provided for
attachment to various types of integrally-reinforced
connections.
If the PIG-SIG V indicator is replacing a PIG-SIG IV
assembly, remove all PIG-SIG IV components.