Wolverhampton-based company Ovivo UK Ltd recently called on the resources of Cat Pumps when it was awarded the contract by a leading international oil producer to supply the Fresh Water Maker Package for two projects located in the West of Shetland area of the UK Continental Shelf. The packages use the reverse osmosis process to produce fresh water from seawater.
Pressure regulator acting as a back-pressure valve
The RO package being supplied by Ovivo requires a pressure regulator to act as a back-pressure valve, which regulates the system pressure allowing reverse osmosis to occur. The Cat Pumps pressure regulator is designed to a maximum set pressure of 70 Bar (1000 psi) and allows for a flowrate of up to 160 l/min (9.6 m3/hr). The Super Duplex components make up the wetted parts of the valve. The selection of this material as well as the design provides excellent resistance to the salt water and gives increased working life to the valve.
Adjustable spring loading allows for smooth operation and maintains close control of the working pressure. The valve is easily serviceable as it does not need to be disconnected from the pipework to access the working parts. The piston seat and Viton O-rings are replaceable as individual parts or as a repair kit.
Challenges: space and weight restrictions, remote location and harsh operating environment
Space and weight restrictions meant that a conventional control valve was not a viable option. Cat Pumps has supplied Ovivo with similar pressure regulating valves on many occasions in the past, but not with the demanding test and certification requirements necessary to meet the client’s specifications.
The remote location and harsh operating environment mean that safe and reliable operation of all components for the life of the package is of paramount importance. To ensure this is the case, Ovivo’s client require all Super Duplex materials to be sourced from approved suppliers, in accordance with their specifications defining material testing requirements, chemical analysis and mechanical properties superior to the normal international standards for this material. These requirements are similar to the Norwegian Standards NORSOK M-630 and M-650.
CAT pumps successfully supplied the valves in accordance with all the standard and specifications required by Ovivo’s customer.
Adapted from press release by Cecilia Rehn