Yakup Turgut

Effects of different cutting methods for electrical steel sheets on performance of induction motors

In this study, by cutting electrical steel stator laminations, one of the most important components of electrical machines by different cutting methods, the effects of these cutting methods on motor efficiency are investigated. As cutting methods, wire electrical discharge machining, punching, laser and abrasive water jet methods are used. Burr formation at the cutting edge leads to short circuits during the steel packaging and causes magnetic losses in steel packages to increase. In addition, depending on the cutting methods, electrical steel lamination insulation layer is damaged as a result of residual and thermal stress formations. These negative conditions cause iron, friction and windage, stator, rotor and additional load losses occurred in the engine to decrease. In order to minimize these cases, electrical steel stator laminations are cut with the cutting parameters determined as a result of pre-cut tests and 5.5-kW induction motors are manufactured. These manufactured motors, according to IEC 60034-2-1-1B method, are subjected to no-load performance tests in addition to six different loading ratios of 25%–50%–75%–100%–115%–125% and constant 50 Hz frequency. As a result of the test measurements, losses occurred in electrical steels cut with abrasive water jet are found to be higher than the other cutting methods. In addition, in terms of the motor performance, the best results are obtained with wire electrical discharge machining cutting method.

Ti-6Al-4V ALA?IMININ FREZELENMESYNDE Y?LEME PARAMETRELERYNYN TAGUCHI METODU KULLANARAK OPTYMYZASYONU

Bu caly?ma Ti-6Al-4V ala?ymynyn karbur takymlarla kuru ?artlarda yuzey frezelenmesinde i?leme parametrelerinin kesme kuvvetleri ve yuzey puruzlulu?u uzerindeki etkilerini ve optimizasyonunu gostermektedir. Deneysel duzen Taguchi metodu kullanylarak belirlenmi?tir. Optimum i?leme parametreleri kombinasyonu sinyal-gurultu orany analizi kullanylarak elde edilmi?tir. Deney sonuclaryna gore, bile?ke kesme kuvveti ve yuzey puruzlulu?u ilerlemenin artmasyyla artarken kesme hyzynyn artmasyyla azalmy?tyr. Hem bile?ke kesme kuvveti (FR) hemde yuzey puruzlulu?u (Ra) icin optimum kesme ?artlary 180 m/dak kesme hyzynda ve 250 mm/dak ilerlemede elde edilmi?tir.