The
Onyx Isolator Ring Out-Performs Conventional Isolator Rings &
Standard Diaphragm Seals (click drawings to enlarge)
Obtaining accurate pressure readings on slurry lines
is difficult because slurries, abrasives and solids
clog pressure elements such as gauges, switches and
transmitters. Isolator rings
consist of a rubber "inner tube" captured
in a steel ring. The assembly is installed between
flanges in the process pipe. Clear instrument oil behind
the rubber membrane transmits pressure to the gauge.
The inside diameter of the ring assembly matches the
adjacent pipe so the ring is continually cleaned by
the motion of the process fluid.
A common
problem with this type of isolator ring is that any
air inside the instrument will compress when
pressurized. This stretches the rubber membrane,
causing accuracy to to degrade or the instrument to
malfunction. (An air bubble as small as a pea can
make an isolator non-functional.) To counter this
obstacle, isolator ring manufacturers use a vacuum
pump to evacuate the air from the isolator before
injecting the instrument fluid. To remove the gauge
for replacement or calibration, the entire ring and
gauge assembly must be removed from the process pipe
and the gauge and ring have to be drained, evacuated
and refilled. This causes considerable downtime and
expense.
Some manufacturers try to
circumvent this problem by adding a valve to the
ring assembly. This holds the fluid in the ring, but
attempting to fill the gauge by turning it upside
down and pouring fluid into it traps an air pocket
at the tip of the Bourdon tube. Also, attempting to
remount the gauge by covering the connection with
your finger while turning it upright and screwing it
into the isolator is rarely successful.
Robust 0.87" dia. mounting
post resists breakage. Provides sturdy mounting for
heavy gauges and instruments. Up to three gauges,
pressure switches and transmitters can be combined
on one isolator without additional support.
The Onyx Isolator Ring The Solid Solution for Solving Your Pressure
Measurement Problems
The Onyx
Isolator Ring provides a practical, cost-effective
method for obtaining accurate pressure measurements
on slurries, abrasives and hard-to-handle materials.
The Onyx Isolator Ring's new
patented design solves the problems associated with
isolator rings on the market today.
The Onyx Isolator Ring is
vacuum-filled at the factory with high-viscosity
silicone fluid; then permanently sealed with Onyx's
Revolutionary "Module-Seal".
With the Onyx Isolator Ring,
there is no fill port anywhere on the assembly:
gauges, switches and transmitters are supplied
separately, are pre-filled with Onyx's special
fitting attached.
Select any combination of
isolator ring and gauge and simply snap them
together.
With the Onyx Isolator Ring, you
are guaranteed hassle-free operation and added protection
for your sensitive indication instrumentation.
The gauge can be
removed from the ring without breaking the vacuum
seal. The rubber "Module Seal" closes the
instant the probe is removed.
Practical
Applications of the Onyx Isolator Ring
The Onyx Isolator Ring
can be used in a variety of industries such as
chemical, food & beverage, mining, pulp &
paper and waste water treatment. Typical applications
include:
Pressure
measurement of slurries, corrosives and difficult
fluids.
Tank Level
Indication.
Monitor pressure on
long distance pipe lines to detect line breaks.
Measure the output
pressure of a pump.
Send a signal to
stop a pump or open a by-pass valve.
Proven Benefits of the Onyx
Isolator Ring
Gauges can be
removed or replaced without interrupting process.
Gauges can be
replaced without vacuum filling.
No tools required
to change pressure instrument (simply remove and
replace by turning the lock ring).
No snubber required
(needle functions as built-in snubber).
Improved safety
(process liquid cannot escape if gauge is removed,
even if process pipe is under pressure).
High accuracy
(because air can never get into the system).
No isolation valve
required.
Gauges can be
rotated by hand to face any direction.
Isolation rings and
gauges can be stocked separately (combine as
needed on the spot).
Technical Specifications of the
Onyx Isolator
Center Section:
Carbon Steel
316 Stainless Steel
Carpenter-20
End Plates:
Acetal
Kynar
316 Stainless Steel
Titanium
Teflon
Carpenter-20
Elastomer:
Neoprene
-20ºF --> 220ºF
Nitrile (Buna-N)
-20ºF --> 180ºF
EPDM (Nordel)
-20ºF --> 300ºF
Fluoroelastomer (Viton)
(Available with optional Teflon coating)
-20ºF --> 375ºF
Chlorosulfonated
Polyethylene (Hypalon)
-20ºF --> 250ºF
Fill Fluid:
Silicone Fluid
-40ºF --> 400ºF
Food Grade Silicone
(Optional)
-20ºF --> 400ºF
Pressure Range:
Vacuum to +1000 psi
- The Onyx Isolator has
been tested by an independent lab to 1,500
psi.
Dimensions
Standard Gauge:
Size: 100mm dia.
Sealed stainless steel case
with crimped ring.
Bronze tube and socket
Liquid filled
ANSI grade B accuracy
+30ºF --> 150ºF ambient
temp range
Available ranges from -30 Hg /
0 / +15
Compound to +1,000 psi.
