Introduction to System Reliability Engineering

Transcription

1 Introduction to System Reliability Engineering

2 Course Instructor Name: Oseghale Lucas Okohue BEng. Msc. CIPMP Position: Manager Business Development Snr. Consultant Summary : Project Management, RAMS of Production Systems (Onshore Offshore Subsea), Drilling Engineering Education : PhD. RAMS of Production System (Onshore Offshore) Inview Msc. Subsea Engineering BEngr. Petroleum Engineering

3 Copyright All rights reserved. No part of this publication may be reproduced or transmitted in any form or by any means, including photocopying and recording without the written permission of the copyright holder, application for which to be addressed to: Such written permission must also be obtained before any part of this publication is stored in a retrieval system of any nature. Brand names, company names, trademarks, or other identifying symbols appearing in illustrations and / or test are used for educational purposes only and do not constitute an endorsement by the author or publisher.

4 Aim Objectives Appreciation of System Reliability Engineering

5 Reliability Engineering Design

6 Outline Expectations Introduction to Reliability Engineering System Load Strength Relationship load Strength Relationship No Overlaps load Strength Relationship Overlaps Objectives of Reliability Engineering Importance of Reliability Engineering Summary

7 Introduction to Reliability Reliability is associated with unexpected failures of products or services and understanding why these failures occur is key to improving reliability. The main reasons why failures occur includes: The product is not fit for purpose or more specifically the design is inherently incapable. The item may be overstressed in some way.

8 Introduction to Reliability Items are designed for a specific operating environment and if they are then used outside this environment then failure can occur. Note : There are many reasons for failure in system the list above is a generic list.

9 System Load Strength Relationship The load and strength of an item may be generally known, however there will always be an element of uncertainty. The strength values of any system components will varies. Some components will be relatively strong while others will be relatively weak. Although most will be of nearly average strength.

10 System Load Strength Relationship Similarly there will be some loads greater than others but mostly they will be average.

11 load Strength Relationship No Overlaps Maximum Load Maximum Strength Note: The load strength relationship with no overlap shows the maximum load and strength that can be withstand.

12 load Strength Relationship Overlaps However if, there is an overlap of the two distributions then failures will occur.

13 load Strength Relationship Overlaps Note: Introduction of safety margin ensures that there is no overlap of these distributions.

14 load Strength Relationship Overlaps Thus, to ensure good reliability the causes of failure need to be identified and eliminated.

15 Objectives of Reliability Engineering Objectives of reliability engineering are as follows: To apply engineering knowledge to prevent or reduce the likelihood or frequency of failures; To identify and correct the causes of failure that do occur; To determine ways of coping with failures that do occur;

16 Objectives of Reliability Engineering To apply methods of estimating the likely reliability of new designs, and for analyzing reliability data.

17 Importance of Reliability Why is Reliability important? Unreliability has a number of unfortunate consequences and therefore for many products and services is a serious threat.

18 Importance of Reliability For example poor reliability can have implications for: Safety Competitiveness Profit margins Cost of repair and maintenance Delays further up supply chain Reputation Good will

19 Summary Reliability is a measure of uncertainty and therefore estimating reliability means using statistics and probability theory. Reliability is quality over time Reliability must be designed into a product or service

20 Summary Most important aspect of reliability is to identify cause of failure and eliminate in design if possible otherwise identify ways of accommodation Reliability is defined as the ability of an item to perform a required function without failure under stated conditions for a stated period of time The costs of unreliability can be damaging to a company

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