Primary Isolation – Monoflange Application Guide: Single Block (SB), Block/Bleed (BB) & Double Block/Bleed (DBB) Valves

Westech Feature Logo 400x270

Monoflanges protect and safely service pressure instrumentation by allowing the operator/maintenance engineer to safely isolate the instrument from the process line and vent any excess pressure in the piping before removing or calibrating the pressure gauge, switch, or transmitter. Monoflanges can also be used in sampling or chemical injection applications & supplied with an integral fitted quill. The TESCOM Anderson Greenwood Instrumentation monoflange products minimize leakage, save installation and operational costs, and enhance safety of personnel.

Where it WORKS

Monoflanges are installed as a part of the instrument ‘tapping point’. These provide an alternative to traditional first block valve arrangements on process lines / vessels in clean (no dirt/debris) gas, liquid, OR steam service and are commonly seen in following applications:

  • Static or differential pressure measurement – the monoflange is the primary ‘first isolation’ valve that connects the process line to the instrument installation interface – this instrument could include pressure gauges, pressure switches, and Pressure / Level / DP transmitters
  • Chemical injection/sampling connections – the customer would inject chemicals or take a sample through the integral quill/check valve connected to the monoflange The top of the monoflange would be connected to the sampling collection point or chemical storage area.
  • Straight isolation applications (open/close, no flow control) / Positive shut-off
  • If a customer requires a smaller/ lighter installation than traditional piping
  • When customers have economic considerations

Primary Isolation – Monoflange Application Guide - Westech 1

WHO needs it

Oil & gas companies – Upstream / Downstream facilities (Platforms, FPSO, wellheads & refineries), chemical/ petrochemical facilities, pipelines / compressor stations, FLNG (Floating Liquefied Natural Gas carriers), Storage tanks, production vessels, etc.

Application PAINS

  • Leakage – the more connections piping has – the more potential leak points. If one of these points starts to leak, the customer could have emissions, safety or environmental issue on their hands
  • Inconsistent pressurization rate– if pressure is increased too quickly to a pressure transmitter, it can damage the sensing element of transmitter, resulting in the pressure being measured incorrectly
  • Ease of Installation – the more gaskets and bolts required, the more expensive and longer the installation/turn around. Time is
  • Ease of Service – Customers want to minimize vibration problems that large instrumentation assemblies can cause as well as easily calibrate/remove transmitters during maintenance / servicing of the
  • Safety – Ensuring secure pressure isolation / venting configuration of process medium to avoid operator accidents
  • Space and Weight – traditional individual first valve arrangements are heavy and space consuming.

Primary Isolation – Monoflange Application Guide - Westech 2

The Monoflange is a compact, economic & powerful solution for primary isolation in static pressure, DP, and Level applications & also for chemical injection and/or sampling connections. It provides a safe, secure, and leak free way for customers to isolate / vent before they service / calibrate their instrumentation.

More Information

For more details about Westech Industrial’s TESCOM AGI product line please visit our website or call and speak to one of our representatives at 1-800-912-9262.

Share This:

More News Articles