Pumping platforms utilizing pumps and compressors are known to often vibrate, causing damage to the entire equipment and affecting the production. It is crucial to consider vibration as one of the important factors while designing the platform structure, as the entire high powered mechanical equipment is supposed to rest on it. Since pumps are known to produce large vibrational frequencies, there may be instances when the structure supporting these pumps may fail, resulting in excessive maintenance costs; as such raising the safety issues. The use of finite element analysis remains the best choice for platform designers to evaluate the vibration response of the structure and its subsequent compensation.
Considering Various Dynamic Forces:
FEA software packages like ANSYS Mechanical is useful in addressing such problems through structural analysis. However, in order to achieve meaningful results, it is crucial to consider the effects of each and every dynamic force that is supposed to act in real operating conditions. The structural analysis should take into account all the dynamic forces, weights, inertia, damping as well as the structure design. Additionally, offshore pumping stations should also consider the effects of dynamic forces resulting due to wind and tidal waves. The platforms also vibrate due to the acoustic resonance in piping systems, which should also be considered while performing the analysis.
Meshing also remains an important factor while performing the structural analysis. Regions predicted as sensitive to vibration must have fine mesh, in order to precisely simulate the response behavior. The analysis broadly includes studying the natural frequencies of the platforms and pumps, which give rise to resonance and vibrations. In order to reduce the vibration, the amplitude, stress and deflection are evaluated against industry guidelines through modal as well as harmonic response analysis.
Once the values are obtained, practical modifications are possible to increase the dynamic stiffness of the support structure. Also, through software assistance, it is ideal to test the platforms for worst-case loading conditions in order to determine the design safety. Finer meshes applied at sensitive regions help in producing precise results, which can be utilized to improve the stiffness at key locations.
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