Belman Design implemented this project to provide a lifting solution for replacing a compensator at a site, one of the largest chemical complexes in Europe. Thus, we have executed a detailed advanced analysis to ensure the steel structure loads and stresses are within the tolerable limits specified by the client, i.e. an analysis of compensator stress and deformation for lifting lugs.

 

Client Challenge
The project was to replace 50+ years old expansion joint installed in the main cooling water lines at a Petchem site in Europe. There were a few challenges to be overcome. The main challenge of the project was to design a unit that fits into the existing pipeline, which the length of the compensator was supposed to be ten meters. The next was to design external hardware supporting the weight of the spool pipe in between the expansion joint’s bellows. In addition, it was a requirement to design the lifting lugs, including the assistance in preparing lifting procedure that ensures safe handling of the unit.

 

Belman Design Solution
In Expansion joint stress analysis, experience plays the most vital role. Therefore, doing a Finite Element Analysis always counts experiences in the piping industry for a reliable result; otherwise, it could consume a long time to complete the task. Similarly, the time was crucial for the client to avoid unnecessary shutdowns; Belman Design was required to analyse a lifting solution in a very short time span and present it in a report including the finite element model geometry, mesh statistics, boundary conditions, simulations and total deformation.

 

Expertise and Experience
The Finite Element Model for this project was created in Ansys Workbench 19.1 software based on 3D simplified modelling of steel parts, including the geometry used for FE model. In addition, 3D solid elements, mainly hex and tetrahedral, were used to discretize the model’s geometry. Above illustrations show the results of mesh generation in Ansys Workbench. It was necessary to introduce lifting slings and the subject analyzed the model to gravity to simulate the lifting operation of the compensator. For this purpose, the ‘remote displacement’ option as a boundary condition was used that connects lifting holes with the end of slings. It has also performed a stress verification of the compensator. Verification of the strength of a compensator could be performed using Equivalent (von-Mises) Stress. The von Mises stress value is supposed to assume the yielding of materials, such as metal, under a complex load. The illustration on the cover page is an Equivalent von Mises stress plot that has been created to indicate the areas for further evaluation. The following drawing shows the calculated solution for lifting by four lifting lugs. These detailed materials in hand, including an analysis of compensator stress calculations and an engineered lifting solution, the client could make reliable and systematic decisions. We at Belman Design always ensure reliable engineered solutions that help our clients with efficiency and safety requirements while saving both time and project cost.