3D FEA models of the pipe supports

Relief Valve Failure

⬇️⬇️ Stress Analysis of a Pressure Relief Valve

A pressure relief valve (PRV) or safety relief valve (SRV) is used to increase safety of thermo-hydraulic plants. The functionality of a relief valve is quite simple: it automatically releases the substance (liquid or gas) from pressure vessels, boilers etc. when the prescribed pressure limit is reached. Common industries using this type of valve include petrochemical, natural gas processing, petroleum refining, food, drinks, cosmetics, pharmaceuticals etc.

In this project, the stresses in a working PRV were analysed.

The geometry and mesh are shown in figures below.

Geometry

Mesh study

For the analysis, nonlinear static structural was selected. The penalty contact with higher stiffness was used for all the contacts. Steel was selected as a default material for the full assembly. In order to preset a pressure limit for the valve, the top spring step was moved downward by 0.15 m (1.5 cm) restricting the closed disk of the valve to open only when the pressure from below increases to ~0.18 MPa (~180 kPa). Two pressure boundary conditions were applied; one on the disk from below and other on the internal surfaces of the body after the disk is opened. First two figures below show the displacement plot of the valve in open state. Vectors in second figure show moving directions of the spring and spindle.

The further three figures below show the stress plots; the first two figures show the stresses in spring and body in opened valve state whereas the third figure shows the stresses in body after the valve was closed. It is worth noting that high stress areas in the body are due to thinner wall in the middle.

The graph below shows the Cauchy stresses in spring plotted over time.

Finally, the figures below show the animation of the final result.