As part of the services regarding dynamic engineering and trouble shooting on dynamically loaded installations, Techno Fysica provides are all kinds of specific calculations. The most commonly used of these are:
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As part of the services regarding dynamic engineering and trouble shooting on dynamically loaded installations, Techno Fysica provides are all kinds of specific calculations. The most commonly used of these are: |
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Alignment calculations (sag & gap method). With these calculations, the optimum bearing positions are calculated. This results in better distribution of bearing reaction forces, gear forces. The result is longer bearing life, less gearbox noise, and less risk of premature bearing failure. |
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Torsional vibration calculations These calculations are made in accordance with the rules of all major classification societies and serve to identify problem areas that may exist within the speed range of the Installation. Standard, the load on gears and elastic coupling (including thermal loading), and vibratory stresses in shafts is calculated. Modifications can be made whilst still in the design stage, which will considerably lower the risk of problems during service. Often very small improvements, for instance by selecting a different stiffness of the selected elastic coupling, will help to increase the useful life of all components of the installation. |
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Lateral vibration calculations of propeller shafts (whirling calculations) and turbo machinery Just like torsional vibration calculations, these calculations are required by classifications societies for larger installations, to minimise the risk of damage or failure |
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Calculations of resiliently mounted installations
Basically, this is just a calculation predicting the behaviour of an installation, mounted on a sub frame or a stiff foundation, and placed on resilient mounts. The idea of such a configuration is to lower the levels of noise and vibrations into the surrounding structure or the building. However, the resilient mounts much be well chosen, or else the effect of a well-meant solution can be adverse, or even disastrous |
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The Finite element method makes it possible to perform calculations on complex geometries, as well as perform calculations which normally can not performed by normal rules or hand methods. Techno Fysica uses the finite element method for both static calculations (strength, stress, strains) as well as in the behaviour of vibration predictions. Furthermore, it is also engaged in failure analysis, |
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Fracture mechanics calculations Using fracture mechanics, the effect of a defect can be evaluated. Often enough, a defect, for instance discovered during routine non destructive testing can set of an alarm, leading to the close down of an installation or plant, and removal or repair of the component. This is not always required, and this can be evaluated by performing calculations with parameter such as crack size, material properties, and loading conditions. |
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The advantages of having these calculations performed are multiple. Some are required by class, such as whirling and torsional vibration calculations. Others are optional. The purpose of these calculations is to optimize the installation within its operational speed range. This will result is less wear, longer life and more reliability of components. In addition, some of the problem areas may be defined in a stage where modifications are still possible at low costs. This may prevent you having to fix a problem when an installation is already commissioned. This usually magnifies the costs involved. Fracture mechanics are applied when a defect, often a crack or corrosive attack, is to be evaluated with regards to allowable dimensions. Within Techno Fysica, this method of calculation is also used as a tool to support failure analysis problems. |
