Stress Analysis and Optimization of Plunger Pump Critical Components

Abstract

This paper presents mechanical strength analysis and optimization of the critical components of the plunger pump. Due to the uneven stress distribution and high contact pressure created between the contacting surfaces the v-packing seals and the PTFE cup were subjected to failure. During the analysis of stresses, the critical components that are considered as a tri-layer compound cylinder such as the assembly of suction tube, PTFE cup, and the check seat and the assembly of plunger, v-packing seals and the spacer tube were analyzed based on the lame’s equation of compound cylinders. The materials that are used for making these components were 316 stainless steel and polytetrafluoroethylene or Teflon that are ductile in nature. The failure criteria’s which are adopted in this analysis was the maximum shear stress /Tresca criteria and the von-misses criteria’s. To optimize the stress distribution in the compound cylinders a classical Lagrangian multiplier method was adopted based on the maximum shear stress theory. The analytically calculated result was compared with the finite element ANSYS simulation software and results from the optimization technique shows that the uneven stress distributions were optimized.

Key words: plunger pump, thick-walled cylinder, tri-layer compound cylinder, stress analysis, Lagrangian multiplier optimization