Dynamics of Pipelines with a Finite Element Method.pdf
6.7 MB
Dynamics of Pipelines with a Finite Element Method
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کاتالوگ نفتا صنعت ناظران- 960425.pdf
19.6 MB
Mechanical Vibration Analysis (Design Approach 3, API 618, 5th Edition)
While pulsation forces can be reduced through the pulsation solution (as outlined in Section 2), the remaining
forces such as gas forces, crosshead forces, mass unbalance and couples, cannot be reduced – they must be
controlled through a mechanical vibration analysis. This analysis provides recommendations on piping supports,
package design, piping, clamps, skid, and other components.
forces such as gas forces, crosshead forces, mass unbalance and couples, cannot be reduced – they must be
controlled through a mechanical vibration analysis. This analysis provides recommendations on piping supports,
package design, piping, clamps, skid, and other components.
Mechanical vibration analysis is part of a Design Approach 3 of API 618, 5th edition. The scope includes calculating Mechanical Natural Frequencies (MNFs) throughout the system and a Forced Response Analysis to predict vibration and stress amplitudes, if necessary.
The goal of the analysis is to avoid mechanical resonance in the compressor/piping system. In many situations, and especially at higher order frequencies, it may be impossible to avoid resonance.
In this case, the engineer must “manage resonance”. Vibration will exist, but through detailed mechanical modeling and Forced Response Analysis techniques, the vibration consultant can predict whether a certain mode or location will have acceptable vibration and stress amplitudes.
In this case, the engineer must “manage resonance”. Vibration will exist, but through detailed mechanical modeling and Forced Response Analysis techniques, the vibration consultant can predict whether a certain mode or location will have acceptable vibration and stress amplitudes.
The mechanical analysis starts by developing an accurate computer model of the mechanical system. The model starts at the compressor (or cylinder); includes the pulsation control devices, scrubber, and main piping, and ends, as a minimum, at the second clamp away from the discharge/suction.
this model includes a (super element) frame FE model to accurately model the boundary conditions of cylinder/piping interface. This superelement frame model is an option for our standard Mechanical Vibration Analysis.