Corrosion in Oil and Gas Wells - Its Causes and Prevention

Abstract

IntroductionThe subject of corrosion is forcing itself to the attention of all branchesof the engineering profession because of the enormous wastes that are involved.Petroleum engineers are obliged to deal with it all the way from the bottom ofthe well to the last still in the refinery and even to the internal combustionengine itself. The subject of corrosion in the petroleum industry is, ofcourse, too broad to cover in a brief paper, but certain phases of its causesand prevention in the producing fields can be outlined to advantage. This paperdeals with underground corrosion in the wells themselves.A large part of the corrosion troubles that are now harassing operators inold fields could have been prevented, at only nominal cost, if protectionagainst the corrosion of well equipment had been properly established when thewells were first drilled and equipped. To wait until corrosion troubles developin an oil or gas field is like waiting until an army develops a typhoidepidemic before applying inoculation against the disease.In presenting this paper, there are three purposes in mind. The first is tooutline briefly the causes for corrosion in oil and gas wells. The second is topoint out reliable methods of detecting corrosive conditions in the wells atthe time they are being drilled and equipped. And the third is to emphasize theadvantages of establishing adequate protection of well equipment againstcorrosion at the time the wells are first drilled and equipped, that is, beforethe corrosion in the wells begins.The effort has been made to outline as briefly as possible a part of theresults of a three-year investigation of the corrosion of oil and gas fieldequipment by the U.S. Bureau of Mines. The subject has been more broadlycovered in Bulletin 233.