Research on corrosion mechanism of pipe elbow with weld overlay using different corrosion-resistant alloys in shale gas field
Author of the article:LIU Jun1, LI Musong2, CHEN Bowen3, ZHANG Fufeng4, ZAN Linfeng1, TANG Xin1, MA Jingxuan4
Author's Workplace:1. CPECC Southwest Company, Chengdu, Sichuan, 610041, China; 2. CPECC, Beijing, 100120, China; 3. Mianyang City College Dingli College, Mianyang, Sichuan, 621000, China; 4. Zhengzhou Wanda Heavy Industry Co., Ltd., Zhengzhou, Henan, 451162, China
Key Words:Shale gas; Pipe elbow with weld overlay; Inconel alloy; Corrosion
Abstract:
The gas composition in shale gas production and
gathering system is complex and can easily cause corrosion and perforation
leading to leakages in equipment and piping, seriously affecting the normal
development and production to shale gas field. Cold-formed carbon steel pipes and cold-formed pipes with Inconel 825 and 316L weld overlay
are designed as experimental pipe sections to assess their corrosion resistant
properties. Simulated sandblast tests and field tests were conductedon these
test sections. The tests results showed that carbon steel pipe elbow were
affected by erosion corrosion and prone to pitting corrosion, while pipe elbows
with Inconel 825 and 316L weld overlay were less affected by erosion corrosion,
with no sign of pitting. Hence, pipe elbows with Inconel 825 weld overlay has
higher cost effectiveness and meet site requirements, and are recommended for
shale gas development. Pipe elbows with 316L weld overlay could be the
alternative solution. The research resultsprovide reference for material
selection of pipe elbows in shale gas field development.