• 한국전산유체공학회:학술대회논문집
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• 2008.03b
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• pp.232-235
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• 2008

The vibration of steam turbine is caused by Mass Unbalance, Shaft Misalignment, Oil Whip and Rubbing etc. but in turbine which is normally operated and maintained, the Mass Unbalance component possesses the greatest portion. Our power plant has two steam turbines in capacity of 200MW and 135MW respectively and each turbine is supported by 6 journal bearings. However, we had many difficulties because the vibration amplitude of No 3 and 4 Bearings was high during the start-up and operation mode change of steam turbine. But, with this study, we completely solved the vibration problem caused by the mass unbalance of No 1 steam turbine. Until a recent date, No 3 and 4 bearings which support high pressure turbine for No 1 steam turbine had shown about 135${\mu}$m in vibration amplitude (sometimes it increased to 221${\mu}$m maximum. alarm: 6mils, trip: 9mils) at base load. After applying the study, they decreased to about 40${\mu}$m maximum. It is a result from that we did not change the setting value of Bearing Alignment and only changed the assembly position of internal parts in Synchro Clutch Coupling Rachet Wheel which links between high pressure turbine and low pressure turbine, and increased the internal gap and machining of the Pawl stopper surface. In the operation of steam turbine, if the vibration value increases by 1X, we should reduce the vibration of bearing by weight balancing. However, unless the vibration of bearing is declined by the balancing, we will have to disassemble and check the component and find the cause. In this study, We researched the way to lower mass unbalance that is 1X vibration component which has the greatest portion of vibration generated by steam turbine and We got good result by applying the findings of this study.

• Journal of Korean Orthopaedic Sports Medicine
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• v.9 no.1
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• pp.7-15
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• 2010

Anterior knee pain syndrome would best be defined as a painful condition that arises in or around the patellofemoral joint and is insidious in onset and bilateral, with an enigmatic entity with multiple causes. Although its etiology is uncertain, the cause is often considered to be abnormal lower limb biomechanics, pathology of extensor mechanism, disorder of patellofemoral joint, malalignment or lateral tracking of the patella, soft tissue tightness, muscle weakness. The measurement of patellar alignment has come to be accepted as an integral part of the examination of anterior knee pain syndrome. Various measurement techniques exist, both clinical and radiological, and these have been frequently used in the diagnosis and treatment of the condition.?Treatment depends on the underlying cause of anterior knee pain and should be directed to the cause rather than to the results. Most often, this involves non-surgical measures, such as anti-inflammatory medications, quadriceps exercises, and hamstring stretching. Shin splint, or medial tibial stress syndrome refers a syndrome of pain running along the inner distal 2/3 of tibia shaft. Shin splint is a common problem for athletes whose sport involves a repeated, jarring impact to the leg. A major factor determining the efficacy of the treatment is that correct diagnosis be made of the problem. The varied etiology has led to the development of several theories as to the cause, treatment, rehabilitation and prevention of shin splint. The management is rest, ice massages, pain relief by medication, and muscle strengthening exercise. Proper rehabilitation and preventative measures can ensure that there is no further recurrence.