Our client approached us with a requirement to examine their temporary refuge blast wall to allow them to get approval for their safety case.
A model was set-up and analysed to demonstrate the wall reacting to a variety of pressures. The acceptable pressure was found to be 0.2 bar. This was supplemented with manual calculations as required.
Apollo worked alongside the client throughout the development of the designs due to the complexity of the existing structure, fabrication, and installation requirements typical of clamp design scopes, with good feedback throughout the scope.
The Problem
- There is insufficient documentation to demonstrate the temporary refuge blast wall allowable rating, however the safety case required analysis to demonstrate that the wall could withstand a maximum blast pressure of 0.2bar.
The Solution
To ensure accurate demonstration of the suitability of the blast wall, the following was undertaken:
- ANSYS Structural Analysis of the blast wall with varying pressures
- Manual hand calculations as required
And for all you engineers who want more details:
The background
Apollo was asked to demonstrate the suitability of the client’s temporary refuge blast wall to withstand a blast pressure of 0.2bar.
A model was created using drawings provided by the client and this was analysed in ANSYS to a variety of pressures affecting the wall surface, excluding the doors & windows as these were assumed to be suitably rated. The boundary conditions were also modelled in based on the drawings & information provided by the client. The acceptance of the FEA was based in line with API codes.
The analysis provided results that showed higher stress points where the welded connections would be. Manual calculations were done to evaluate the welded connections not explicitly modelled in the analysis.
The solution
Apollo delivered a Basis of Analysis document to ensure the client was happy with how we were going to proceed with modelling the blast wall, and a report which contained all the information used and results from ANSYS, as well as the local checks from manual calculations.
We gave our conclusion and recommendations where we found the wall can survive the predicted maximum blast pressure of 0.2bar. We suggested that it may be possible to further increase the maximum blast pressure if required by creating a significantly more complex model with more rigorous analysis, however, the approach used was both efficient and accurately demonstrated the integrity of the wall in the event of a blast.
What did the client think?
We worked alongside the client throughout the development of the designs due to the complexity of the existing structure, fabrication, and installation requirements typical of clamp design scopes. The client was delighted with our approach to not just look to fix the problem but to complement the work already undertaken by their team. As a client who had primarily used Apollo across other disciplines, this was a great scope to work on and they were very impressed.
The client couldn’t fault the support we provided:
I was very happy with the report which has now been issued as part of the safety case. I thought that there was excellent communication throughout and that you guys have a great understanding of the project and what was expected. I couldn’t fault the work you put in. Thanks for your help and the effort you put in.
If you have a pressing issue and need engineering support, let us know on oilandgas@apollo.engineer