Performance Characteristics of Drilling Equipment Elastomers Evaluated in Various Drilling Fluids

Abstract

ABSTRACT The type of elastomer chosen for use in drilling equipment can mean the difference between a normal service life or sudden unpredictable failure. Drilling fluids can chemically alter elastomers in equipment used for drilling oil and gas wells. The degree and magnitude of this interaction depends on the type of the drilling fluid, temperature, pressure, and chemical formulation of the elastomer. Certain components of drilling fluids, such as the base oil in an oil-base mud, can cause changes in weight, volume, and hardness of elastomeric compounds. These changes can affect the resulting performance of the elastomer. This paper will discuss different types of elastomeric compounds and their performance in various drilling fluid systems. The focus will be on elastomers used in downhole drilling equipment such as stator material which is an important component in positive displacement motors (PDMs). Field data concerning the performance of certain elastomers in specific drilling fluids will be discussed. Results of recent elastomer immersion tests in various fluids used in the drilling industry are presented.