含气地层采卤井生产套管被气体刺破原因分析

Analysis on the Reason of Gas Puncturing the Production Casing of Brine Well in Gas Bearing Formation

陕北盐田某盐矿部分卤井停产检修期间高压天然气刺破生产套管从孔洞处喷出,对矿山安全生产造成很大的威胁。本文分析了套管外腐蚀、天然气在溶腔内聚集的原因,提出高压天然气在溶腔内受压力、温度变化而体积膨胀置换生产套管内液体的观点,计算出套管内介质被天然气置换后地面段的内压力,反算出生产套管腐蚀的厚度,针对该问题提出生产应对措施。

High pressure natural gas punctures the production casing and ejects from the hole during the shutdown and maintenance of some brine wells in a salt mine in Northern Shaanxi Province,Great threat to mine safety production.This paper analyzes the causes of corrosion outside the casing and the accumulation of natural gas in the solution cavity,The viewpoint that high pressure natural gas volume expands due to pressure and temperature changes in the solution cavity to replace the liquid in the production casing is put forward,Calculate the internal pressure of the surface section after the medium in the casing is replaced by natural gas,Back calculation of corrosion thickness of production casing,Put forward production countermeasures against this problem.