Corrosion in geothermal is a process of material degradation caused by the chemical or electrochemical reaction of the geothermal fluids with the exposed surface of the material of the equipment. Most of the geothermal equipment is made from carbon steel material owing to its superior mechanical properties and high strength. However, carbon steel materials are susceptible to corrosion in low pH acidic, and hyper-saline geothermal fluid environments.
A lot of geothermal wells are not being utilized in the world because they are producing aggressive fluids which are either acidic or hyper-saline. This makes them corrosive to carbon steel. For subsurface requirements such as production casing and production liner, we supply pure corrosion-resistant alloy (CRA) such as 25Cr or 17Cr materials to eliminate corrosion at the subsurface level,
At the surface level, from wellhead to geothermal gathering systems, we eliminate corrosion with the application of weld-overlay cladding of critical geothermal equipment such as casing head flange (CHF), Master Valve, Wing Valves, Production Cross, Production Tee, Through Conduit Valve (TCV), and the rest of piping spools, fittings, and downstream valves.
A variety of CRA material are available that can be used in weld-overlay cladding. Currently, the material of choice by geothermal clients is Inconel Alloy 625. Inconel Alloy 625 material performed well in anti-corrosion application in acidic geothermal fluids as low as pH 2.2. We have provided cladded Master Valve to EDC in the Philippines in one (1) of its acid geothermal well production. In Indonesia, we have collaboration with Sarulla Geothermal Operations to supply weld-overlay cladded materials for five (5) wells that include cladded CHF, cladded Master Valve, cladded wing valves, cladded Production Cross, cladded production tee, piping spool, cladded elbow spool, cladded injection spool, and cladded sampling spool.
Inconel alloy 625 has been the anti-corrosion material of choice in Oil and Gas, petrochemical, and chemical industries. Wilclad bring this knowledge in anti-corrosion control in geothermal applications so that those aggressive wells will be utilized to give geothermal clients additional geothermal production, increased power generation, and increase rate of return.