Process Capability Studies in an Automated Flexible Assembly Process: A Case Study in an Automotive Industry

Document Type: Research Paper

Authors

1 Faculty of Industrial and Systems Engineering, Tarbiat Modares University, Tehran, Iran

2 Department of Industrial Management, Faculty of Management, University of Tehran, Iran

3 Department of Industrial Management, Faculty of Management and Economics, Tarbiat Modares University, Tehran, Iran

Abstract

Statistical Process Control (SPC) methods can significantly increase organizational efficiency if appropriately used. The primary goal of process capability studies is to obtain critical information about processes to render them even more effective. This paper proposes a comprehensive framework for proper implementation of SPC studies, including the design of the sampling procedure and intervals as well as process capability indices. Some of the most essential process capability indices in the literature were reviewed to develop a methodology to utilize process capability indices within the SPC framework. The current study presents an efficiency-oriented criterion designed for measuring SPC implementation productivity. The framework is applied to the windshield installation process of an Iranian automobile assembly line. The process was sampled in various sessions. Results verify that the implemented SPC framework could successfully improve the process and that the proposed framework could significantly address bottleneck in the process and enhance the quality level of the process from satisfactory to excellent according to the reference values of process capability indices. Managerial insights are also drawn from results.

Keywords

Main Subjects


Article Title [Persian]

مطالعات قابلیت فرآیند در فرآیندهای مونتاژ اتوماتیک انعطاف‌پذیر (مطالعه موردی: در یک شرکت خودروسازی)

Authors [Persian]

  • بختیار استادی 1
  • محمدرضا تقی زاده یزدی 2
  • عبدالکریم محمدی بالانی 3
1 دانشکده مهندسی صنایع و سیستم ها، دانشگاه تربیت مدرس، تهران، ایران
2 گروه مدیریت صنعتی، دانشکده مدیریت، دانشگاه تهران، تهران، ایران
3 گروه مدیریت صنعتی، دانشکده مدیریت و اقتصاد، دانشگاه تربیت مدرس، تهران، ایران
Abstract [Persian]

سازمان‌هایی که روش‌های کنترل آماری فرآیندها را به نحو موفقیت‌آمیزی اجرا کنند از بازده قابل توجهی برخودار خواهند بود. هدف یک برنامه بهبود کیفیت بر اساس SPC، بهبود مستمر بطور هفتگی، فصلی و سالی است. SPC برنامه‌ای نیست که فقط سازمان آن را یکبار و آن هم در زمان بروز مشکل از آن استفاده کند و هنگامیکه مشکل برطرف شد کنار گذاشته شود. لازم به ذکر است که, عناصر موثر در اجرای موفقیت آمیز SPC عبارتند از رهبری مدیریت,  نگرش تیمی,  آموزش پرسنل در کلیه سطوح , مکانیزمی برای تشخیص موفقیت و  تأکید بر بهبود مستمر. هدف اولیه استفاده از مطالعات قابلیت فرآیند اینستکه اطلاعاتی درباره فرآیند کسب کنیم. این اطلاعات یک پایه‌ای را برای بهبود فرآیندها شکل می‌دهند که به فرآیندهای تواناتر منجر می‌شوند. . اگر شاخص‌های قابلیت فرآیند بطور مناسب مورد استفاده قرار گیرند، اطلاعات با ارزشی در مورد قابلیت یک فرآیند در اختیار قرار می‌دهند. این اطلاعات برای بهبود عملکرد فرآیندها مفید هستند و باعث کاهش هزینه‌های تولید و رضایت بیشتر مشتریان می‌شوند. در این مقاله, شاخص‌های قابلیت فرآیند ارائه و مراحل جامع پیاده سازی کنترل فرآیند آماری با در نظر گرفتن مطالعات قابلیت فرآیند بیان شده و در فرآیند نصب شیشه یک شرکت خودروسازی پیاده و نتایج آن نیز بیان گردیده است. به منظور اندازه‌گیری بهره‌وری اجرای کنترل فرآیند آماری شاخصی تعریف شده است. بوسیله این شاخص، تیم اجرایی بطور کمی مشخص می‌کند که در شروع کار چه وضعیتی داشته و مدتی پس از اجرا چه پیشرفتی صورت گرفته است. اندازه گیری این شاخص بهبود را نشان داد.

Keywords [Persian]

  • کنترل آماری فرآیند
  • مطالعات قابلیت فرآیند
  • شاخص‌های قابلیت فرآیند
  • تجهیزات مونتاژ خودرو
  • فرآیند نصب شیشه جلو
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