Pentair Valves and Controls has announced that it has provided maintenance support under its specialist service brand, SABO, for a valve repair project at one of the largest gas storage facilities in Europe. After experiencing leakage of ball valves in the facility, Pentair was contracted to discover the reason for the loss of seal tightness and provide maintenance to solve the issue within a short timescale.
On examination of the critical ball valve, Pentair discovered corrosion of the seat and inner valve body, and identified that the seat required reworking and a hard-facing. By determining the root of the problem, providing a mirror polished surface to the ball and adjusting the clearance with new o-rings, Pentair completed the job almost two weeks ahead of schedule, which helped to minimise downtime and loss of production for the 17 billion m3 gas storage facility. This also led to the early start of the pipeline testing procedure, which in turn allowed for early restart of the full pipeline.
The 30 in./750 CL 600 ball valves were located between the depleted gas reservoir used as storage 2500m underground at the facility, and the pipeline system. Featuring an actuator with a high integrity pressure protection system (HIPPS) function, the valves isolate the high pressure gas storage from the pipeline system. It was essential that Pentair delivered a successful and rapid outcome in order for the customer to fulfill their critical requirement of injecting gas into storage tanks by a fixed deadline.
The repair project posed a number of challenges for Pentair to manage, including handling due to the weight of the valves of more than 15 t when assembled with the actuator. The extremely hard surface of the outer valve body also proved problematic. To overcome this, the previous coating, a two component polyurethane specific to offshore pipelines, was removed and grid blasted, which required special cast steel splitters . The Pentair team completed the mirror polishing of the valve ball, which helped to ensure the early completion of the valve service.
Edited from press release by Callum O'Reilly
Read the article online at: https://www.lngindustry.com/liquid-natural-gas/16032015/pentair-supports-ball-valve-repair-project-421/