Condition-based maintenance offers a system check-up
Condition-based maintenance (CBM), when used with a computerized maintenance management system (CMMS), can help to implement a preventative maintenance plan.
For most drivers, it's the mileage sticker that reminds them that it is time to change the oil. It's hard to imagine the average car owner waiting until his engine ceases before he realizes he's four quarts low. Even if he waits till the lantern icon flashes on the dashboard, he'll no doubt raise some eyebrows at the gas pump.
Likewise on the plant floor—if a gear box low in oil costs production time and product output, the culprit may be looking for a new job. The production machine equivalent of the 3,000 mile oil change reminder is condition-based maintenance (CBM): one part native technology to monitor all equipment pieces and parts, and two parts computerized maintenance management system (CMMS) to set the thresholds and issue the work orders. Keeping equipment in optimal condition is done with the help of CMMS by implementing a preventative maintenance (PM) plan and schedule, and completed work orders.
Let's say a compressor is out of alignment. The machine's vibration detection system continually monitors the machine. It picks up the imbalance and forwards the data in numerical form to an OPC server where a CMMS retrieves the data and converts it to actionable information. A CMMS not only tracks the compressor's maintenance and repair history, but sets up a CBM if the alignment falls below tolerance levels, and issues a work order to make the adjustments.
CBM utilizes the combined vibrational analysis and corresponding maintenance tasks dictated by the CMMS to fine-tune machine performance and keep the asset humming.
A thermal camera picks up a heat signature in a motor which indicates a pending failure. Now what? The analysis from the infrared camera is an impetus for further action by the CMMS, which sets threshold levels and spits out work orders as needed. A pressure gauge shows two different pressure readings for both sides of an air handler filter. Again, CMMS grabs the data from the server and makes sense out of it. CMMS sets tolerance levels and automatically issues work orders to make the repairs. Another CBM process fulfilled.
If you're going to employ a CBM strategy and make the investment in monitoring technologies, be sure to tie machine operations data to your CMMS where ongoing maintenance can be tracked. Keep in mind, CBM will not cover all maintenance needs. You'll still need regularly scheduled PMs for routine maintenance based on machine manufacturers’ recommendations and intelligence gathered over time by your CMMS.
Most manufacturing or facility equipment will come with built in sensors to keep an eye on equipment behavior. The idea behind CBM is to perform the necessary maintenance when the machine tells you to do so. But if you make an investment in equipment-based monitoring hardware, it should be used in conjunction with CMMS.
Paul Lachance is president and chief technology officer for Smartware Group, producer of Bigfoot CMMS. Lachance has been developing and perfecting the company’s CMMS solution for the maintenance professional for 20 years. Check out his blog, Lachance on CMMS, at www.plantengineering.com/blogs.