Abstract

Within reliability engineering, different time periods are being used to determine time-related reliability parameters. For example, when determining the mean (expected) time to failure (MTTF) of downhole pumps, typically the operating times or running times are used. But, in some cases, also periods where the pump is available (in an up state), and idle for whatever reason (e.g. surface facilities are down), could be included. ISO 14224:2016 and IEC 60050-192:2015 are key documents guiding reliability data collection and analysis in the petroleum, petrochemical and natural gas industries. However, not much guidance is provided in these documents on what circumstances one should use one time period or another. Furthermore, the concept of running time is lacking a formal definition, and the way it differs from operating time could be given more focus in these documents.

In this paper, we discuss the perceived gaps in international standards and how further guidance could be provided to achieve consistent use of reliability parameters and associated terminology across the industries addressed, focusing on the MTTF. We refer to a downhole pump example, and cross-reference also the ISO/TR 12489:2013, to clarify implications for reliability modelling and calculations. One suggestion is the introduction of the terms running time to failure and operating time to failure, which would be consistent with existing terminology, while also clarify the time periods being referred to.

Author: Selvik, Jon T., Signoret, Jean-Pierre, Alhanati, Francisco J.S.

Publisher: European Safety and Reliability Association

Year: 2019

Purchase LinkESREL Conference

RELATED CONTENT

Filter by
Post Page
Insights Media Room Latest News - Home Page Piramid Latest News - Piramid Full Scale Testing
Sort by
2020-06-04

8

2020-04-29

0

Do you have a question or comment?

If you are interested in our engineering or testing services, want a demo of a software product, want to join a joint industry project, or are interested in a training course, we want to connect with you.

Please complete the contact form and we will respond within 48 hours.

Follow us on LinkedIn to keep up-to-date on the latest happenings at C-FER.