Machine safety and degrading component reliability

Is your machine downtime sometimes a surprise? Did a component in a safety circuit fail because it simply wore out and nobody knew it was about to fail? Well, maybe help has just arrived. Has anyone heard about EN ISO 13849-1; 2008? See "4 ways to reduce surprise downtime."

07/14/2011


JB Titus, CFSEIs your machine downtime sometimes a surprise? Did a component in a safety circuit fail because it simply wore out and nobody knew it was about to fail? Well, maybe help has just arrived. Has anyone heard about EN ISO 13849-1; 2008?

   This new standard (Safety of machinery, Safety-related parts of control systems) has arrived and the Machinery Directive in Europe has established its effective date as Jan. 1, 2012. Since the US is part of the ISO (International Standards Organization) many companies in the US are making plans to or have already adopted this new standard. In my opinion, 13849-1 improves machine safety because it moves machine safety from qualitative Categories to quantitative Performance levels. Compliance requirements in this new standard will now address all of the components in a safety circuit while determining that circuit’s Performance Level. As such, the expected life of a component is determined and documented relative to its expected number of cycles during machine operation. Therefore, the weak links can be identified and flagged early on during the design stage. This is particularly important for those components that are electro/mechanical, such as contactors or safety relays, and have moving parts or points that wear out over time. This wearing out over time is what many people refer to as “degrading component reliability”.

   OK, great! Does anyone have an idea with this information how to reduce the surprise downtime (and possible hazard) related to this type of component failure?

4 ways to reduce surprise downtime

   Several thoughts I have are as follows:

1.)   Identify and document these components in your risk assessment for the machine.

2.)   Add these components to your preventive maintenance plan.

3.)   Plan for routine machine maintenance to replace these components before their expected failure.

4.)   Update your risk assessment for the machine.

   I have barely touched on the comprehensive approach for Functional Safety addressed by EN ISO 13849-1; 2008. Several companies and consultants offer two and three day classes on the new compliance requirements embedded in this new standard. In my opinion, to fully understand these compliance requirements you should consider contacting these sources and consider enrolling in one of their classes.

   Your comments or suggestion are always welcome so please let us know your thoughts. Submit your ideas, experiences, and challenges on this subject in the comments section below. Click on the following text if you don't see a comments box, then scroll down: Machine Safety & Degrading Component Reliability.

   Did you see the Safety Integration Webcast?

   Related articles:

EN ISO 13849-1; 2008 - Are We Ready? - Part 2

Trouble Implementing ISO 13849-1; 2006 per the European Machinery Directive

B10s at work for machine guarding

Contact: www.jbtitus.com for “Solutions for Machine Safety”.



The Engineers' Choice Awards highlight some of the best new control, instrumentation and automation products as chosen by Control Engineering subscribers. Vote now (if qualified)!
The System Integrator Giants program lists the top 100 system integrators among companies listed in CFE Media's Global System Integrator Database.
Each year, a panel of Control Engineering and Plant Engineering editors and industry expert judges select the System Integrator of the Year Award winners in three categories.
This eGuide illustrates solutions, applications and benefits of machine vision systems.
Learn how to increase device reliability in harsh environments and decrease unplanned system downtime.
This eGuide contains a series of articles and videos that considers theoretical and practical; immediate needs and a look into the future.
Maximize ROI with integrated control system approach; Microcontrollers vs. PLCs; Power quality; Accelerate and rewire IIoT; Traits for excellent engineers
HMI effectiveness; Distributed I/O; Engineers' Choice Award finalists; System Integrator advice; Inside Machines
Women in engineering; Engineering Leaders Under 40; PID benefits and drawbacks; Ladder logic; Cloud computing
Programmable logic controllers (PLCs) represent the logic (decision) part of the control loop of sense, decide, and actuate. As we know, PLCs aren’t the only option for making decisions in a control loop, but they are likely why you’re here.
This digital report explains how plant engineers and subject matter experts (SME) need support for time series data and its many challenges.
This article collection contains several articles on how advancements in vision system designs, computing power, algorithms, optics, and communications are making machine vision more cost effective than ever before.

Find and connect with the most suitable service provider for your unique application. Start searching the Global System Integrator Database Now!

Control room technology innovation; Practical approaches to corrosion protection; Pipeline regulator revises quality programs
Cloud, mobility, and remote operations; SCADA and contextual mobility; Custom UPS empowering a secure pipeline
Infrastructure for natural gas expansion; Artificial lift methods; Disruptive technology and fugitive gas emissions
Automation Engineer; Wood Group
System Integrator; Cross Integrated Systems Group
Jose S. Vasquez, Jr.
Fire & Life Safety Engineer; Technip USA Inc.
This course focuses on climate analysis, appropriateness of cooling system selection, and combining cooling systems.
This course will help identify and reveal electrical hazards and identify the solutions to implementing and maintaining a safe work environment.
This course explains how maintaining power and communication systems through emergency power-generation systems is critical.
click me