Butterfly valves have simple geometric structures and are lightweight. This makes them suitable for use in petrochemical, metallurgical steelmaking, water treatment, and Electric power applications. However, these valves are susceptible to flow separation and vortex shedding. This leads to pressure fluctuation close to the disc-stem assembly which causes structural vibration. Consequently, steam pressure fluctuations lead to damage to the valve structure and pipeline systems. Therefore, analyzing the characteristics of the fluid forces acting on the disc-stem assembly is essential for the performance enhancement of this type of valve. Check this out: shiphamvalves.com
The existing single and double-offset butterfly valves have a simple design and are easily manufactured. But rubbing and friction between the seal and seat during opening and closing shorten their lifetimes. Triple eccentric butterfly valves solve this problem by using a three-eccentric design which enables metal-to-metal contact throughout the full operating cycle. This cam action eliminates rubbing and reduces wear between the sealing surfaces, thereby prolonging their life.
Triple Eccentric Butterfly Valves in Oil and Gas: Critical Applications and Benefits
The purpose of this study is to analyze the frequency spectrum of pressure fluctuation near the disc-stem assembly of a triple eccentric butterfly valve with different inlet flow rates. This will enable us to predict the stability of the valve against steam pressure fluctuation and the resulting effects on the structural vibration of the valve. The analysis is based on the CFD method, which simulates 3D unsteady steam flow inside the valve and obtains the transient pressure and velocity at key points in five typical sections of the fully open state.