Indicator Ports

Monitor Cylinder Pressure

Regular diagnostic testing is key to extending compressor runtimes and avoiding unplanned downtime. Many compressors, however, are not manufactured with indicator ports to allow pressure monitoring.

While adding a tapped indicator port requires cylinder disassembly, machining and hydrotesting – introducing cost, downtime and risk of damage to the cylinder – Cook indicator ports provide safe, easy access for monitoring cylinder pressure.

Valve indicator port

Non-invasive, Secure Access

A Cook indicator port valve provides access to cylinder pressure using a connection that passes through the center of a valve and extends out the cylinder. An indicator valve mounted on the end of the indicator port allows pressure readings to be taken manually, using a pressure transducer, or automatically, using an online monitoring system.

Cook indicator ports are designed to fit existing compressor valve ports, eliminating the need to machine or modify the cylinder. They can be included with any new MOPPET®, Manley® or Optima™ Series compressor valves, or retrofit to existing valves as part of upgrade projects. They can be applied to either suction or discharge valves.

Cook indicator ports are also compatible with most valve restraint designs. If the existing restraint uses a jack bolt, Cook Compression will upgrade it to an HSR design, which features multiple studs for stronger retention.


  • Streamlines pressure monitoring to promote safe, reliable compressor operation
  • Provides non-invasive access to cylinder pressure
  • Designed to fit existing valve ports
  • Available with any new Cook compressor valve or as retrofit to existing valves
  • Robust, secure assembly with no center bolt

Related Case Study

Valve solutions for LNG storage

Condition Monitoring Leads to Valve Solutions

When a series of compressors in boil-off gas service started to experience a spate of valve failures, Cook Compression valve indicator ports simplified the job of acquiring data for analysis.