An Ergonomically Sound Encapsulating System Application in an Automotive Stamping Press Line for Reducing Employee Noise Exposure

Abstract

Stamping press lines are among the highest noise sources in the automotive industry. The noise limits imposed by OSHA (Occupational Safety and Health Organization) force companies to keep employees away from these high-decibel noises. The most ergonomic and effective program for noise safety is to block the noise at the source. In this study, a press line of the Renault-Turkey automotive plant was enclosed with a novel foam-core sandwich structure to improve the comforts and ergonomics of the stamping press workshop environment. Three different encapsulating cases were applied: four sides circumferentially closed with soundproofing walls, five sides encapsulated with a closed top, and a gap-reduced case. For all three cases, the sound levels were measured in the stamping press workshop. The sound levels were reduced below 85 dB (A) in all cases. The performance of the encapsulating system was observed while producing two different parts. It was determined that this type of stamping press line should be encapsulated on all five sides to reduce the stamping workshop noise level. The four lateral sides’ sound barriers were not sufficient to soundproof the press line. The small gaps and the die changing doors were very important in the all-five-sides encapsulated case.

Keywords

• Sound Proofing,Press Line,Sandwich Structures,Workshop Ergonomics,OSHA,Noise

Çalışanların Gürültü Maruziyetini Azaltmak için Otomotiv Sac Şekillendirme Pres Hattında Ergonomik Bir Ses Yalıtım Sistemi Uygulaması

Öz

Sac parça üretiminde kullanılan pres hatları otomotiv endüstrisindeki en yüksek gürültü kaynakları arasındadır. OSHA (Mesleki Güvenlik ve Sağlık Örgütü) tarafından getirilen gürültü limitleri şirketleri çalışanlarının bu yüksek şiddetteki gürültüden uzak tutmaya zorlamaktadır. Gürültü güvenliği için en ergonomik ve etkili yöntem gürültüyü kaynağında engellemektir. Bu çalışmada, Renault Türkiye otomotiv fabrikasının bir pres hattı, pres atölyesi ortamının konforunu ve ergonomisini geliştirmek için yeni bir köpük çekirdekli sandviç yapısı ile tamamen kapatılarak ergonomik bir gürültü önleme uygulaması gerçekleştirilmiştir. Üç farklı kapatma tasarımı denenmiştir: a) Dört cepheden çevresel olarak kapatılmış gürültü önleme sistemi, b) Tavanı da kapatılan beş cepheli sistem ve c) açıklıkları azaltılmış beş cepheli kapatma sistemi. Her üç durumda da, pres atölyesinde gürültü seviyeleri ölçülmüştür. Tüm durumlarda gürültü seviyesi 85 dB (A) altına düşürülmüştür. Geliştirilen gürültü yalıtım sistemlerinin performansı iki farklı sac parçanın seri üretimi esnasında ölçümlenerek gözlemlenmiştir. Pres atölyesi gürültü seviyesini düşürmek için uygulama yapılan pres hattının beş cepheden kapatılmasının gerektiği tespit edilmiştir. Sadece dört yan cepheli kapatma sisteminin diğer ikisine göre daha başarısız olduğu görülmüştür. Beş cepheli kapatma sisteminde küçük açıkların dahi iyileştirilmesinin ses yalıtımına önemli katkısı olduğu tespit edilmiştir.

Anahtar Kelimeler

• Ses Yalıtımı,Pres Hattı,Sandviç Yapı,OSHA,Gürültü,İşyeri Ergonomisi

Kaynakça

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