The author describes how the crankshaft fillet stresses are measured using FM radio link strain telemeter.
The results of the measurements were summarized as follow;
1) When the additional stress by resonance is smaller, there are good agreements between the measured fillet stresses and calculated ones which are computed considering the resilience of main bearings.
2) The alternating bending stresses were found on fillet at the resonance of torsional vibration.
3) On large two stroke cycle engine crankshaft alternating bending stresses were found at the resonance of axial vibration. And the mode curve estimated from the measured stress differ from the one calculated theoretically.
4) Axial vibration damper is effective to reduce the bending stress induced by axial vibration, but ineffective to reduce the bending stress induced by torsional vibration.

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This is intended to make the basic explanation what steam condition, what system of auxiliaries are the best in the marine reheat turbine plant.
As the result of efficiency calculation in scope of the auxiliary system in four kinds, of output 16-64×10³ PS, steam conditions 450-570°C, 30 kg/cm²-200 kg/cm², it is reached to the conclusion that:
(1) The optimum ratio of reheat point against the initial pressure is 15-25%.
(2) The initial pressure 60-80 kg/cm² is optimum at non-reheat cycle with conventional auxiliary system. But, the initial pressure 100 kg/cm² or above can be optimum for the reheat cycle in the improved auxiliary system such as the main turbine direct driven generator. In consideration of thermal stress and other practical condition, the steam condition of 100 kg/cm²/520°C/520°C is proposed in the range of 20-40×10³ PS.
(3) An auxiliary turbine system of the feed pump are discussed, in which the auxiliary turbine is driven by steam extracted at not reheated point, and the auxiliary turbine bleed and exhaust to the feed heaters located at lower pressure side of the reheater. This system make possible to use less superheated steam for feed heating than using the steam extracted from the main turbine. The efficiency improvement by the system can be almost the same as main turbine direct driven feed pump system. Considering the convenience in operation, this system has some advantage.

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