Instrumentation Valves

Needle Valves are primarily used to isolate delicate pressure instrumentation in Oil & Gas applications. A needle valve is comprised of a small, shaped flow port and a threaded, needle-shaped plunger. By moving the needle into the port aperture it allows very precise flow regulation. Needle valves can cope with pressures (up to 10,000psi), and are often manufactured from high-grade stainless steel or other exotic alloys.

A simple, quarter-turn instrumentation Ball Valve is another method of isolating pressure in aggressive environments. An instrumentation ball valve contains a hollow pivoting ball, which, through rotation, enables the control of flow by varying the size of the aperture. Instrumentation ball valves are usually a quarter-turn solution, with full flow at a 90-degree angle. One of the benefits of an instrumentation ball valve is that the control handle can be set in line with the aperture of the ball, which provides a quick visual indication of the status of the valve. Instrumentation ball valves are generally more economical than Needle Valves.

Preventing Back Pressure in highly critical Oil & Gas applications is a supremely important task. Instrumentation Check Valves are often used to perform such duties. The instrumentation check valve allows flow in one direction only, closing when flow reverses. In other words, it is a non-return valve used for isolation within process measuring apparatus. Instrumentation check valves are available in a wide range of materials and are able to perform at high pressures.

As a safety precaution, many process applications require ‘Double Isolation’ to protect employees and plant integrity whilst performing maintenance. Here, Double Block & Bleed valves are used. A Double Block & Bleed Valve consists of two isolation valves, with a bleed or vent valve in the middle to bleed off any excess pressure. When both valves are in the closed position they will provide a seal against pressure from both ends which allows the cavity between the two to be drained. Double Block & Bleed Valves are critical in applications where piping needs isolation for maintenance, and are often found in oil & gas industries.