For an ammonia plant in Western Australia, cooling water is supplied by a Sea Cooling water (SCW) as well as a Fresh Cooling Water (FCW) system. Both piping systems were constructed out of fiberglass material with pipe diameters of up to 72”. Heat exchangers acts as the interface between the two systems. A significant part of the piping is installed above ground.
Since the day of commissioning the seawater system has had repeated failures, mainly in the above ground piping. A root cause analysis has been performed, combining a study of failure information, site visits, material testing and engineering analyses. The study indicated a relatively large number of weaknesses and deficiencies both in the material and in the design.
Part of the CW system has been replaced and the remaining CW system has been mitigated by measures that reduces the pipe stresses. The engineering for the replacement piping as well as construction supervision was performed by Dynaflow. Focus was on achieving uncompromised quality while achieving the turnaround job in a minimal downtime.