FATIGUE ANALYSIS OF PROCESS EQUIPMENT USING FINITE ELEMENT METHOD

OBJECTIVE

A significant supplier of process equipment and pressure vessels requested CADE’s services to perform design validation for fatigue of a process reactor, aimed to be installed in a petrochemical plant.

Validation of mechanical design, previously conducted by the manufacturer, was carried out according to ASME VIII Div.2 (“Fatigue Assessment – Elastic Stress Analysis and Equivalent Stresses”), and based on final user and licensor’s design specifications. Design conditions with respect to the cyclic service conditions (T+P) were considered. Fatigue analysis was conducted by using finite elements method simulation software (ANSYS).

METHODOLOGY AND ANALYSIS

In order to carry out the design validation, CADE initially conducted a fatigue screening, following the design code prescriptions, to determine whether a fatigue analysis was indeed necessary or not, considering materials, design conditions and expected number of cycles.

Results determined that fatigue analysis was necessary, so the following analysis were then executed:

Transient thermal analysis considering cycles of thermal and mechanical loads.
Static structural analysis, in order to determine alternating stresses (Sa) derived from equipment’s operation and regeneration cycles.

EXPERIENCE

CADE has acquired more than 15 years of a wide experience in design and validation of process equipment, pressure vessels, heat exchangers and storage tanks, among other equipment. CADE counts on specific capabilities and tools for thermal, hydraulic and mechanical design, as well as advanced analysis and simulation (FEM / CFD) in compliance with most common codes and standards in Oil & Power (TEMA, API, ASME VIII div. 1 & 2, AD2000, EN13445 , etc.). Equipment suppliers, engineering, EPC Companies and plant owners s are some of CADE’s regular clients.

Author: Adrian García Moyano