Analytical Sizing and Modal Analysis Verification of Circular Saw Shafts

Abstract

In circular saw machines used for cutting aluminum and PVC profiles, saw shafts are subjected to structural damage due to torsional moments, fatigue effects, and possible resonance. This study aims to determine appropriate material selection and perform analytical sizing for a safe, durable, and efficient shaft design under specified boundary conditions. During the design process, the mechanical properties of AISI 1040, 1050, 4140, and 4340 steels were compared. While analytical methods were used in the shaft diameter calculations, modal analysis was conducted using the “Half-power bandwidth” method to evaluate the dynamic behavior of the system and the risk of resonance. Analytical calculations revealed that the minimum safe shaft diameter for AISI 4340 steel, which has the highest strength among the evaluated materials, is 11.7 mm. As a result of the static analysis, the maximum shear stress occurring on the shaft was determined to be 4.2 MPa. Frequency analysis results confirmed that the system’s operating frequency of 50 Hz remains outside the critical resonance band.It was determined that the obtained minimum shaft diameter values are compatible with the existing shaft dimensions and meet safe design criteria. Consequently, the study demonstrates that in designing a safe saw shaft, geometric sizing alone is not sufficient; material properties must be evaluated together with static, fatigue, and dynamic behavior in an integrated manner.

Keywords

• Shaft Design
• Vibration Analysis
• Design Parameters
• Modal Analysis

Dairesel Testere Millerinin Analitik Boyutlandırılması ve Modal Analiz Doğrulaması

Öz

Alüminyum ve PVC profil kesiminde kullanılan dairesel testereli makinelerde, testere milleri burulma momenti, yorulma etkileri ve olası rezonans nedeniyle yapısal hasarlara maruz kalmaktadır. Bu çalışma, belirlenen sınır koşulları altında güvenli, dayanıklı ve verimli bir mil tasarımı için uygun malzeme seçimini ve analitik boyutlandırmayı amaçlamaktadır. Tasarım sürecinde AISI 1040, 1050, 4140 ve 4340 çeliklerinin mekanik özellikleri karşılaştırılmıştır. Mil çapı hesaplamalarında analitik yöntemler kullanılırken, sistemin dinamik davranışını ve rezonans riskini değerlendirmek için "Half-power bandwidth" yöntemi ile modal analiz uygulanmıştır. Analitik hesaplamalar, en yüksek mukavemetli malzeme olan AISI 4340 çeliği için minimum emniyetli mil çapının 11,7 mm olduğunu ortaya koymuştur. Statik analiz sonucunda mil üzerinde oluşan maksimum kayma gerilmesi 4,2 MPa olarak belirlenmiştir. Frekans analizi sonuçları, sistemin 50 Hz olan çalışma frekansının kritik rezonans bandının dışında kaldığını doğrulamıştır. Elde edilen minimum mil çapı değerlerinin mevcut mil ölçüsü ile uyumlu olduğu ve güvenli tasarım kriterlerini sağladığı tespit edilmiştir. Sonuç olarak, güvenli bir testere mili tasarımında yalnızca geometrik boyutlandırmanın yeterli olmadığı; malzeme özellikleri ile birlikte statik, yorulma ve dinamik davranışın bütüncül olarak değerlendirilmesi gerektiği ortaya konmuştur.

Anahtar Kelimeler

• Mil Tasarımı
• Titreşim Analizi
• Tasarım Parametreleri
• Modal Analiz

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