Fatigue Life Enhancement of Three Point Hitch System Brackets in the Garden Series Tractors

Abstract

The main objective of this research was to enhance the fatigue performance of the brackets found in the three point hitch system used in garden series tractors. This was achieved by using experimental tests and finite element analysis. The manufactured brackets were validated with fatigue rig tests, namely a lifting capacity test, a push-pull test and a liftinglowering test. The lifting capacity test of three point hitch mechanism was established according to ISO 730-1 standards. In addition to the lift capacity test, problems were also experienced with the cylinder clamping brackets during the pushpull tests. The bracket brakeage occurred during the 11,218th test cycle. According to the test results and finite element analysis, the brackets were strengthened at critical damage points. The thickness of the bracket connection surface was increased from 12 mm to 19 mm and the bracket material was changed from GG25 to GG35. The enhanced brackets passed the tests without any breakage

Keywords

• Hydraulic lift,Three point hitch mechanism,Push-pull tests,Lifting-lowering tests,Fatigue analysis,Stress analysis

Bahçe Tipi Traktörlerin Üç Nokta Askı Sistemi Braketlerinin Yorulma Ömürlerinin İyileştirilmesi

Abstract

Bu araştırmanın temel amacı bahçe tipi traktörlerde kullanılan hidrolik kaldırıcılı üç nokta askı sistemi bağlantı braketlerinin yorulma performanslarını iyileştirmektir. Bu amaca deneysel ve sonlu elemanlar analizi yardımıyla ulaşılmıştır. Üretilmiş olan braketlere kaldırma kapasitesi testi, çek bırak testi ve indir kaldır yorulma testleri uygulanmıştır. Kaldırma kapasitesi testleri ISO 730-1 standartlarına göre gerçekleştirilmiştir. Kaldırma kapasitesi testlerine ek olarak uygulanan çek bırak testlerinde silindir bağlantı braketlerinde problemler gözlenmiştir. Denemelerin 11218. çevriminde braketlerde kırılmalar görülmüştür. Test sonuçları ve sonlu elemanlar analizlerine göre braketlerin kritik hasar bölgeleri güçlendirilmiştir. Braket bağlantı yüzeyinin kalınlığı 12 mm’den 19 mm’ye çıkartılmıştır ve GG25 olan braket malzemesi GG35 olarak değiştirilmiştir. İyileştirilen braketler, deneysel testleri kırılma olmadan tamamlamıştır.

Keywords

• Hidrolik kaldırıcı,Üç nokta askı sistemi,Çek bırak testi,İndir kaldır testi,Yorulma analizi,Gerilme analizi

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