Preventive Maintenance for Instrumentation

Share on linkedin
Share on twitter
Share on facebook
Share on email

IDCON often gets the question, “What kind of Preventive maintenance should be in place for instrumentation?” from maintenance managers with mechanical background.  The exact answer will vary from plant to plant depending on equipment and level of automation, but in general on can divide the preventive maintenance tasks for instrumentation as follows:

Instrumentation devices needs to be calibrated from time to time to make sure they show the right value.  The interval is different from different devices, brands and styles.  Some suppliers give up to 10 years warranty on the device they sell to stay true, others are less.  But, if you are a non-instrumentation manager, look for calibrations in your instrument PM’s.  

Control Loop Checks
Part of an instrumentation preventive maintenance program is to check your loop response.  For example, if you set a flow to 22 gpm, the flow should become 22 gpm.  In tests by control loop experts such as Fisher and others, on average, the typical plant have about 80% of their control loops respond incorrectly.  Part of the loop response problem can be design issues.  It is for example not uncommon to see plants select a valve that is larger than needed, which result in errors.  If a maximum flow is supposed to be 30 gpm and a larger than necessary valve is chosen, the maximum flow may be achieved at 75% open and the range will therefore be 0-75% for the corresponding 0-30 gpm, instead of 0-100%.

Physical Instrumentation Checks
All instrumentation should be checked physically in our opinion.  Most instrumentation people I’ve met resist doing these checks. I’m not sure exactly why.  While a packing leak on a valve , a damaged transmitter, or a damage membrane on a regulator eventually will show up on a computer screen somewhere, it is not always the problem can be pinpointed to physical damage, or to what device(s) that have the problem.  A physical inspection route for instrumentation equipment will pinpoint physical problems and identify problems earlier.  It is a must for a world class instrumentation preventive maintenance program.  

An idea may be to have your operators do physical inspections of instrumentation and mechanical equipment? 

Need to have operators trained in basic equipment and instrumentation functionality and in how to inspect equipment? Call Tor Idhammar at IDCON +1 919 723 2680

At IDCON, we understand the pressure you face trying to build a reliable plant.
We provide side-by-side reliability and maintenance consulting and training designed to keep your equipment running.

For over 45 years, we’ve partnered with 100s of manufacturing plants around the world to eliminate the costs and the pressure caused by unreliable equipment. And we’d love to do the same for you.

Contact us today to see how we can help you keep your plant running.

Related Articles

Torbjörn Idhammar

Torbjörn Idhammar

President & CEO, IDCON Inc. Reliability and Maintenance Consultant

Want weekly Reliability & Maintenance Tips?

Best practices. Common sense. Pratical tips.
All designed to help you and your team keep your plant running

IDCON © 2020 All rights reserved

Free Download & Video

8 Steps to Successfully Implement Preventive Maintenance

Reduce your costs with an effective PM program