Optimized Valve Stem Design in Oil and Gas Industry to Minimize Major Failures

Abstract

A valve is a mechanical component in a piping system that is used to open and close the fluid passage, avoid return of the fluid, control the flow, or for safety purposes. An industrial valve contains different parts in general, such as pressure-controlling and pressure-containing parts. The valve stem is categorized as a pressure-containing part, and failure of this component leads to leakage of the fluid to the environment. Thus, failure of the valve stem leads to asset losses, oil or gas spillage into the environment, human injury or death, and in general health, safety, and environmental concerns. Therefore, this article addresses some of the main stem design features to minimize the risk of failure in stem. The main design features are the maximum allowable stem torque to enable the stem to handle the operator torque or force, stem diameter calculation, material selection, anti-blow out and anti-static design. Different materials for the stem, especially those with high mechanical strength, are proposed in this article. The anti-blow out design feature and solutions for stem and closure member connection, as well as stem and body connection, have been explained in detail. The anti-static design will provide electrical continuity among the stem, ball, and body to minimize the risk of fire inside the valve due to the accumulation of static electricity in the valve’s soft materials, which has been explained. The valve stem sealing is not included in this article and requires separate research.