2.0 Introduction
2.1 Purpose
The purpose of this manual is to
provide instructions for the
installation, operation and
preventative maintenance of the
complete TDW PIG-SIG
IV
Scraper Passage Indicator and
installation of a PIG-SIG
indicator assembly on a plug
assembly already set in a
pipeline.
2.2 Description
The TDW Scraper Passage
Indicator (PIG-SIG IV) is a
device that is installed on a
pipeline to detect the passage of a
pig or sphere.
The PIG-SIG IV has a trigger that
extends into the pipeline through
a welded fitting that has been
tapped. When a pig passes, the
trigger is tripped, activating the
signaling mechanism.
Signaling mechanisms available
include a flag indicator, electrical
indicator, combination flag and
electrical indicator, or rotary cap
indicator. All indicators are
compatible with all standard plug
assemblies now in the field and
are interchangeable.
This makes it possible to use
these units as conversion kits as
well as complete PIG-SIG
Indicators.
The PIG-SIG IV is weatherproof
and corrosion resistant. It features
housings manufactured from
space age plastic for durability
and weather resistance. The flag
indicator offers high visibility
from the air or ground.
The carbon steel nipple is
manufactured
from easily
weldable material. The PIG-SIG
Plug Assembly can be installed
on or removed from a pressured
pipeline using a TDW T-101 or
T-101b Drilling Machine and
accessories.
The PIG-SIG IV is available in
various combinations of
operation, indication and
materials of construction,
depending on piping
requirements, including:
• Flag Indicator with Manual
Reset flag
• Rotary Cap Indicator with
Manual Reset
• Electrical Indicator with Auto
Reset
• Flag/Electrical Indicator with
Auto Reset
• Indicator Extensions from 1
foot to 15 feet
• Unidirectional or Bidirectional
Trigger Mechanisms
• Special Materials and O-Ring
Seals
• Models for Environmentally
Harsh Conditions
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