Surge Suppression

When a surge study shows that surge pressures will pose problems, or when problems are found on existing systems then it is necessary to consider surge suppression techniques.

If the risks are identified at an early design stage then it is sometimes possible to fundamentally change the design so that the surge problems are avoided. We sometimes call this an ‘inherently safe’ system. But this can be a costly solution and many designs do not have the flexibility required to accomplish this.

So, it is common to install surge suppression equipment to control, or mitigate, the surge pressures. The type and size of suppression equipment depends upon the precise problem, the system itself and needs of the final asset owner/operator. Generally we consult intensively with our clients to find techniques that have a suitable performance and a tolerable life-time cost.

The following brief list summarises the most common surge protection equipment:

Air/Surge Vessels
Pressure Relief Valves (surge relief valves)
Bursting Discs
Fast acting (non-slam) NRVs
Inline NRV
Surge tower
Flywheels
Shutdown systems (such as high pressure trips)
Air Valves and Vacuum Breakers
Slow Valve Closure
Variable Speed Drives
Soft start/stop controllers

Not all of these can be used on ever systems and not all will protect against all surge problems. Choosing the best alternative to prevent a problem requires a surge analysis, some good consultation and productive discussions with our clients. Normally surge suppression equipment can be used to protect systems and is a cost-effective solution to most problems.

Surge Suppression

Water