CORROSION MANAGEMENT OF DUPLEX STAINLESS STEEL GAS PRODUCTION FLOWLINES

摘要

Onshore gas production facilities commonly consist of a network of flowlines feeding the gas inlet manifold before processing. A number of operators use duplex stainless steel (DSS) as one of the materials of construction (MOC) for gas flowlines due to their good corrosion resistance with the aim of avoiding extensive maintenance and providing high gas production availability. However duplex stainless steels (DSS's) can still be susceptible to internal and external corrosion threats in both above-ground and buried environments. The threat of corrosion can be effectively managed if DSS flowlines are operating within their integrity operating window (IOW) and the material limits are clearly understood. For these reasons effective corrosion management of gas flow lines is one of the core requirements in maintaining the integrity of gas assets and extending their period of operation beyond their design life. This paper will present a methodology for corrosion management of DSS flowline installations. This paper will also discuss flowlines preservation strategy during the long periods of well shutdowns, and threats associated with stray current interference.