A Novel Magnetic Equivalent Circuit Approach in Magnetic Flux Leakage Test System Design

Abstract

Magnetic Flux Leakage (MFL) is a widely used non-destructive testing method for ferromagnetic materials in the industry. Using this method, defects occurring within the material structure are detected, and their characteristics are evaluated. The design of the MFL test system, which performs the inspection process, is of critical importance for the reliable and accurate detection of these defects. Although three-dimensional (3D) magnetic analysis simulations used during the design phase produce highly accurate results, they incur high computational and time costs. An alternative approach to reducing this computational burden is the design of the MFL test system using the Magnetic Equivalent Circuit (MEC) method. In this study, a novel Segmented MEC (SMEC) model is proposed for magnetic system design. The validity of the developed SMEC model was tested on an MFL test system design. For this purpose, a sample MFL test system was analyzed in a 3D FEM simulation environment, and the obtained data were recorded as a performance reference. Subsequently, both the conventional MEC and the proposed SMEC models were developed for the designed MFL test system, and analysis results were generated. The performances of both methods were examined by taking the 3D FEM results as a reference. The findings demonstrate that the SMEC model achieves approximately 11% higher accuracy than the conventional MEC model.

Keywords

• Electromagnetic non-destructive testing
• magnetic flux leakage
• segmented magnetic equivalent circuit.

Manyetik Akı Kaçağı Test Sistemi Tasarımında Yeni Bir Manyetik Eşdeğer Devre Yaklaşımı

Abstract

Manyetik Akı Kaçağı (MFL), endüstride ferromanyetik malzemeler için yaygın olarak kullanılan tahribatsız bir test yöntemidir. Bu yöntem kullanılarak, malzeme yapısında oluşan kusurlar tespit edilir ve özellikleri değerlendirilir. Muayene işlemini gerçekleştiren MFL test sisteminin tasarımı, bu kusurların güvenilir ve doğru bir şekilde tespit edilmesi için kritik öneme sahiptir. Tasarım aşamasında kullanılan üç boyutlu (3D) manyetik analiz simülasyonları oldukça doğru sonuçlar üretse de, yüksek hesaplama ve zaman maliyetlerine neden olmaktadır. Bu hesaplama yükünü azaltmanın alternatif bir yolu, Manyetik Eşdeğer Devre (MEC) yöntemi kullanılarak MFL test sisteminin tasarlanmasıdır. Bu çalışmada, manyetik sistem tasarımı için yeni bir Bölümlü MEC (SMEC) modeli önerilmiştir. Geliştirilen SMEC modelinin geçerliliği, bir MFL test sistemi tasarımı üzerinde test edilmiştir. Bu amaçla, örnek bir MFL test sistemi 3D FEM simülasyon ortamında analiz edilmiş ve elde edilen veriler performans referansı olarak kaydedilmiştir. Daha sonra, tasarlanan MFL test sistemi için hem geleneksel MEC hem de önerilen SMEC modelleri geliştirildi ve analiz sonuçları üretildi. Her iki yöntemin performansı, 3D FEM sonuçları referans alınarak incelendi. Bulgular, SMEC modelinin geleneksel MEC modeline göre yaklaşık %11 daha yüksek doğruluk sağladığını göstermektedir.

Keywords

• manyetik akı kaçağı
• Elektromanyetik tahribatsız muayene
• bölümlü manyetik eşdeğer devre.

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