Surge Relief systems

Surge Relief System

Surge Relief Systems are widely used in many applications such as major oil pipe lines, sea terminals, tank farms etc. Generally all systems where pressure is contained require some kind of pressure safety relief.

Ignoring this rule endangers both personnel and equipment and may lead to serious damage of valuable assets and environment and the potential for loss of life.

Taken as an example, Pipeline Surge Relief System is meant to relief pressure surges which occur at moments when pumping modes and flowrates change. Such change can be caused by opening/closing of valves and/or change of operating modes of the pumps.

The rate of transmission of such pressure surge along the pipeline is extremely fast. Therefore in order to relief it in time special Nitrogen loaded Axial type relief valves with high relief volume capacity and very rapid response (opening) time (100 milliseconds) are required. The conventional spring type relief valve can respond (open) to fast rising pressures but it tends to immediately slam/close down once the pressure is relieved only locally at particular point of the pipeline. This leads to constant and rapid opening and closing cycles which seriously restrict the valve capacity to relieve excessive pressure and causes the upstream pressure to climb rapidly to unacceptable levels, making the situation even worse.

Surge Relief Skid 3D

In case with Nitrogen loaded axial type relief valves, valve closure is gradual and configured in a way to equalize the pressure along the whole pipeline.

As a summary all Surge Relief Systems designed and supplied by us have following essential basic features:

  • Fast opening – Relief valves react fast enough to be able to equalize rapidly rising pressure;
  • Non-Slam capability – valves return to the closed state gradually but fast enough to avoid relieving excessive volume of fluid from pipeline system;
  • High capacity – Surge Relief System should be able to relief fluid at rates equal to maximum overall flowrate through the pipeline, if it’s required.

Depending on required relief flow rate Surge Relief System can be equipped with a single of multiple Surge Relief Valves installed in parallel arrangement. Configuration of a particular Surge Relief System (relief valves quantity, size and pressure rating) is determined by our engineers on the basis of the transient processes simulation calculations.

Surge relief systems can be supplied as a skid-mounted solution or located inside modular building / enclosure produced in-house.