Silindirik tornalama sırasında meydana gelen çap hatalarının deneysel olarak araştırılması

Torna tezgâhında işlenen bir iş parçasının çap hatası üzerinde araştırma yapılmıştır. İki uçundan bağlı 450 mm boyunda iş parçasını 24 mm çaptan 16 mm çapa kadar ve bir uçundan bağlı 150 mm boyunda iş parçasını 24 mm çaptan 17 mm çapa tornalama işlemi yapılmıştır. Tornalama sırasında kesme kuvvetleri etkisinde iş parçasında sehim meydana gelmektedir Lazer Uzunluk Sensoru ile iş parçasına temas etmeden sehim miktarı ölçülmüştür. Aynı zamanda, her tornalama sonrası mikrometre ile iş parçasının değişik yerlerinden çap değeri ölçülmüştür. Çap hatasının sehim miktarı ile orantılı olarak değiştiği gözlenmiştir. Sehimin en fazla olduğu noktada çap hatasının da en büyük olduğu görülmüştür. Ayrıca, çap hatasına sebep olan talaş derinliği, ilerleme oranı ve kesme hızı gibi faktörler belirlenmiştir.

Experimental investigation of diametric errors during cylindrical turning

The experimental investigation was made on the diametric error of a workpiece machined on a lathe. The diameter cut from 24 mm to 16 mm of the 450 mm long workpiece in turning between centers and the diameter cut from 24 mm to 17 mm of the 150 mm long workpiece in cantilever bar turning has been realized. There was a deflection on the workpiece during the turning as a result of the pressure of the cutting forces. The deflection on the workpiece was measured with a laser distance sensor with no contact. At the same time, the diameter values from different parts of the workpiece were measured with a micrometer after each turning. It was observed that the diametric error and the deflection were changing proportionally. It was also observed that the larger the diametric error was it greater the deflection. In addition, the factors caused the diametric error as the depth of cut, feed rate and cutting speed were determined.

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