pH Buffer Provides Corrosion Control Alternative for High Temperature Well Completions

Abstract This study applied a pH buffer as a corrosion inhibitor in brine packer fluids. The study systematically evaluated the effect of pH buffer on corrosion control of steel materials at elevated temperatures up to 425°F. The paper describes laboratory results of pH buffer in sodium chloride, potassium chloride, sodium bromide and sodium chloride/sodium bromide brines and field case histories for buffered brine packer fluids in high-temperature high-pressure wells. The pH buffer applied is cost effective, readily available and easily handled and monitored in the field. Results from buffer capacity, general corrosion and stress corrosion cracking tests are presented. Field case histories are presented to demonstrate the successful use of the pH buffer in brine packer fluids at high temperatures.