Print this pageSeawater Systems
Currently, the need for reliability and high availability is paramount on utility systems such as Seawater systems, so the consequences of failure can be costly. But failure can be common. Surge pressures and transients have caused weld failure, fatigue to pipes and damage to heat exchangers.
Equipment damage leading to shortened life or shutdowns can also occur. Non-return valves can be prone to damage as can air vents (vacuum breakers) and some control valves.
Most of the failures occur during start-up or shutdown of the system, but some systems have problems when starting or stopping individual exchangers.
These problems can be overcome by either careful design or by remedial measures and revised operating procedures in existing systems.
Surge pressures also cause dynamic forces in Seawater systems that move pipes and develop excessive stresses. The technology to study these dynamic forces caused by transient pressures is recent (over the last 5-10 years) and is still not universally used. So older systems are particularly prone to pipe movement which can cause failures and fatigue in some systems.
We have also investigated air pockets in systems that cause poor flow distribution and hence inadequate heat exchange. These (often) small air pockets can also amplify transient pressures leading to unstable, or unpredictable, operation and system shutdown.
