Tapped Vent CONQUEST® Couplers
CONQUEST® Plastic Lined Piping uses a mechanical
coupler over a welded liner to provide a leak-free, flangeless
joint. PTFE lined systems require a venting system to prevent
permeants from collecting between the liner and steel shell. The new
tapped vent coupler provides more flexibility by allowing a variety
of devices to be attached to the coupler:
For insulated pipe, vent paths should be provided between
vent holes and the atmosphere. Failure to do so often results in
accelerated corrosion of the steel shell and contamination of the
insulation. (Learn more about Venting and Insulation).
PTFE-lined CONQUEST® is designed to vent at the
coupling. The new coupling has a 1/8"
NPT tapped vent hole which
allows extenders to be threaded in, and routed through the
Tests show that a breech in the liner or weld
usually results in fluid traveling through the spiral grooves
on the metal ID to the annular space between the butt weld and
the coupling body. Attachment of leak detection devices to the
tapped vent can provide early warning of a liner failure.
In some cases, venting of even minute quantities of
permeants to the atmosphere is undesirable. This may be true with
extremely hazardous or toxic chemicals, or in environmentally
sensitive areas. The tapped vent allows attachment of collection
systems to prevent permeant release to atmosphere.
High Integrity vent extender featuring Fire-Safe Design
A Hastelloy® porous disc vent fitting is shipped with
the coupler as an optional
addition to the completed installation. It's porous nature allows
permeated gases to escape the system, but contains any entrained
liquids which may result from a liner breech. The vent fitting is also
designed according to the same principles as the Fire-Safe Factory
Mutual approved HIF system.
The tapped vent coupler is different than the standard vented
coupler. The tapped vent holes required a thicker cross section in
the coupler body than is possible with the standard coupler. The groove that accommodates the jaw of the installation
tool was previously located in the center of the coupler. The new
center rib requires that the groove be located on both sides of the
new rib. These changes add to the overall length of the coupler.
There is adequate design tolerance in the CONQUEST®
fittings to use the longer tapped vent coupler without concern for
joint make-up clearance. The exact length of standard vented and the
new tapped vent couplers are as follows: