Desktop version

Home arrow Engineering

  • Increase font
  • Decrease font


<<   CONTENTS   >>

Introduction

Reliability History

The history of the reliability field goes back to the early years of the 1930s when probability concepts were applied to electric power generation-related problems [1,2]. During World War II, Germans applied the basic reliability concepts for improving reliability of their VI and V2 rockets. In 1947, Aeronautical Radio, Inc., and Cornell University carried out a reliability study of over 100,000 electronic tubes. In 1950, an ad hoc committee on reliability was formed by the United States Department of Defense and in 1952 the committee was transformed to a permanent body: Advisory Group on the Reliability of Electronic Equipment (AGREE) [3]. Also, in 1952, a nowadays widely used exponential probability distribution in reliability field received a distinct boost after the publication of an article [4], presenting failure data and the results of various goodness-of-fit tests for competing failure distribution.

In 1964, the first time a National Symposium on Reliability and Quality Control was held in the United States, and in the following year, the Institute of Electrical and Electronic Engineers (IEEE) formed an organization called the Reliability and Quality Control Society. In 1956 and 1957, the following three important documents concerning reliability appeared:

  • • 1956: a book entitled Reliability Factors for Ground Electronic Equipment [5],
  • • 1957: first military reliability specification: MIL-R-25717 (USAF): Reliability Assurance Program for Electronic Equipment [6],
  • • 1957: AGREE report [7].

In 1962, the first master’s degree program in system reliability engineering was started at the Air Force Institute of Technology of the United States Air Force (USAF), Dayton, Ohio. Moreover, ever since the inception of the reliability field many organizations and individuals around the globe have contributed to it, and has branched out into many specialized areas including software reliability, mechanical reliability, and human reliability.

Additional information on reliability history is available in Design Reliability: Fundamentals and Applications [8].

Need of Reliability in Product Design

In the past, there have been many factors responsible for considering reliability in product design including product complexity, past system failures, the awareness of cost effectiveness, insertion of reliability-related clauses in design specifications, competition, and public demand. The first three of these factors is described below in detail:

  • Product complexity. In this case, even if we consider the increase in the product complexity with respect to parts alone, there has been a phenomenal growth of some products. For example, a typical Boeing 747 jumbo jet was made up of around 4.5 million parts, including fasteners. Even for relatively simpler products, there has been a significant increase in complexity in regard to parts. For example, in 1935 a farm tractor was made up of 1200 critical parts and in 1990 the number increased to approximately 2900.
  • The past system failures: In this case, well-publicized system failures such as those presented below may have also contributed to more serious consideration of reliability in product design [9-11]:
  • Point Pleasant Bridge Disaster: This bridge was located on the West Virginia/Ohio border and collapsed in 1967. This disaster caused 46 deaths and its basic cause was metal fatigue of a critical eye bar.
  • Space Shuttle Challenger Disaster: This debacle took place in 1986, in which all crew members lost their lives. The main reason for the occurrence of this disaster was design defects.
  • Chernobyl Nuclear Reactor Explosion: This debacle also took place in 1986, in the former Soviet Union, in which 31 deaths occurred. This disaster was also due to design defects.
  • Awareness of Cost-Effectiveness: In this case, many studies conducted over the years indicated that the most effective for-profit contribution is the involvement of reliability professionals with product designers. In fact, according to the judgments of some experts, if it costs $1 to rectify a design defect prior to the initial drafting release, the cost would increase to around $10 after the final release, $100 at the prototype stage, $1000 at the pre-production stage, and $10,000 at the production stage.

Reliability Application and Specialized Areas

Ever since the inception of the reliability field, the reliability discipline has branched into many applications and specialized areas such as follows:

  • Robot reliability. This is an emerging new area of the application of basic reliability principles to robot-related problems. Over the years, many publications on the subject have appeared, including two textbooks [12, 13].
  • Power system reliability. This is a well-developed area and is basically concerned with the application of reliability principles to conventional power system-associated problems. Over the years, many books on the subject have appeared, including a large number of other publications [14].
  • Medical equipment reliability. This is also an emerging new area of the application of basic reliability principles to medical equipment-associated problems. Over the years, many publications on the subject have appeared, including one textbook [15].
  • Computer and Internet reliability. This is also an emerging new area of the application of basic reliability principles to computer- and Internet-related problems. Over the years many publications on the topic have appeared, including one textbook [16].
  • Mining equipment reliability. This is also an emerging new area of the application of basic reliability principles to mining equipment reliability-associated problems. Over the years, many publications on the subject have appeared, including one textbook [17].
  • Transportation systems reliability. This is also an emerging new area of the application of basic reliability principles to transportation systems reliability- related problems. Over the years, many publications on the topic have appeared, including one textbook [18].
  • Oil and gas industry equipment reliability. This is also an emerging new area of the application of basic reliability principles to oil and gas equipment reliability-associated problems. Over the years many publications on the topic have appeared, including one textbook [19].
  • Software reliability. This is a very important emerging area of reliability as the use of computers and other electronic devices is increasing at an alarming rate. Many books have been written on this topic alone and a comprehensive list of publications on the topic may be found in Refs. [20,21].
  • Mechanical reliability. This is concerned with the reliability of mechanical items. Over the years, many textbooks and other publications on the subject have appeared. An extensive list of publications on the topic is available in Dhillon [22].
  • Human reliability. This is a very important emerging area of reliability, as in the past, many times systems failed not due to technical faults but due to human errors. The first book on the topic appeared in 1986 [23] and an extensive list of publications on the topic is available in Dhillon [21].
  • Structural reliability. This is concerned with the reliability of engineering structures, in particular civil engineering. Over the years a large number of publications including books have appeared on the topic [24].
 
<<   CONTENTS   >>

Related topics