Machinery Lubrication magazine published by Noria Corporation
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the top 20 percent of failure causes are responsible for roughly 80 percent of the failure occurrences. It only makes sense to focus resources and condition monitoring on the top 20 percent. Failure modes and failure root causes are closely associated and are often the same. For instance, abrasive wear may be the failure mode, but particle contamination is the root cause. Ignorance, culture, insufficient maintenance and poor machine design are all possible pre-existing conditions that individually or collectively lead to contamination. Because you can always search for deeper levels of "cause," for simplicity, the terms "failure mode" and "root cause" are used interchangeably. Figure 1 shows the relationship between machine and lubricant failure. On the left are common causes (failure modes) of lubricant failure (LFM) and machine failure (MFM). For example, heat, aeration and contaminants are known to be highly destructive to lubricants. In a similar sense, overloading, misalignment and contamination can abruptly cause a machine to fail. Note how contamination not only can fail a lubricant but also can fail a machine directly without the need to harm the lubricant first. It is best to not only list failure causes but also to rank them in terms of probability and severity. This helps allocate resources by priority. From lubricant and machine failure come specific consequences, which are listed on the right in Figure 1. Again, these consequences are mutually exclusive. Lubricant failure consequences include oil replacement costs, downtime during the oil change, labor to change the oil and flushing costs. Machine failure consequences relate to safety, spare parts, labor to repair and downtime (e.g., production losses). Machinery Lubrication 3 PUBLISHER Mike Ramsey - mramsey@noria.com GROUP PUBLISHER Brett O'Kelley - bokelley@noria.com EDITOR-IN-CHIEF Jason Sowards - jsowards@noria.com SENIOR EDITOR Jim Fitch - jfitch@noria.com TECHNICAL wRITERS Jeremy Wright - jwright@noria.com Wes Cash - wcash@noria.com Alejandro Meza - ameza@noria.com Bennett Fitch - bfitch@noria.com Loren Green - lgreen@noria.com CREATIvE DIRECTOR Ryan Kiker - rkiker@noria.com GRAPHIC ARTISTS Julia Backus - jbackus@noria.com Terry Kellam - tkellam@noria.com Josh Couch - jcouch@noria.com Patrick Clark - pclark@noria.com ADvERTISING SALES Tim Davidson - tdavidson@noria.com 800-597-5460, ext. 224 MEDIA PRODUCTION MANAGER Ally Katz - akatz@noria.com CORRESPONDENCE You may address articles, case studies, special requests and other correspondence to: Editor-in-chief MACHINERY LUBRICATION Noria Corporation 1328 E. 43rd Court • Tulsa, Oklahoma 74105 Phone: 918-749-1400 Fax: 918-746-0925 Email address: jsowards@noria.com MACHINERY LUBRICATION Volume 14 - Issue 3 May-June 2014 ( USPS 021-695) is published bimonthly by Noria Corporation, 1328 E. 43rd Court, Tulsa, OK 74105-4124. Periodicals postage paid at Tulsa, OK and additional mailing offices. POSTMASTER: Send address changes and form 3579 to MACHINERY LUBRICATION, P.O. BOx 47702, Plym - outh, MN 55447-0401. Canada Post International Publications Mail Product (Canadian Distribution) Publications Mail Agreement #40612608. Send returns (Canada) to BleuChip International, P.O. Box 25542, London, Ontario, N6C 6B2. SUBSCRIBER SERVICES: The publisher reserves the right to accept or reject any subscription. Send subscription orders, change of address and all subscription-related correspondence to: Noria Corporation, P.O. Box 47702, Plymouth, MN 55447. 800-869-6882 or Fax: 866-658-6156. Copyright © 2014 Noria Corporation. Noria, Machinery Lubrication and associated logos are trademarks of Noria Corporation. All rights reserved. Reproduction in whole or in part in any form or medium without express written permission of Noria Corporation is prohibited. Machinery Lubrication is an independently produced publication of Noria Corporation. Noria Corporation reserves the right, with respect to submissions, to revise, republish and authorize its readers to use the tips and articles submitted for personal and commercial use. The opinions of those interviewed and those who write articles for this magazine are not necessarily shared by Noria Corporation. CONTENT NOTICE: The recommendations and information provided in Machinery Lubrication and its related information properties do not purport to address all of the safety concerns that may exist. It is the respon - sibility of the user to follow appropriate safety and health practices. Further, Noria does not make any representations, warranties, express or implied, regarding the accuracy, completeness or suitability of the information or recommendations provided herewith. Noria shall not be liable for any inju- ries, loss of profits, business, goodwill, data, interruption of business, nor for incidental or consequential merchantability or fitness of purpose, or damages related to the use of information or recommendations provided. MACHINE FAILURE MODE (MFM) RANkING (Example below) Overall Machine Criticality (OMC) Score 100 90 80 70 60 50 40 30 20 10 1. Particle Contamination CM1 CM1 CM1 CM2 CM3 CM3 CM3 CM4 CM4 CM5 2. Water Contamination CM1 CM1 CM2 CM3 CM3 CM3 CM4 CM4 CM5 CM5 3. Varnish & sludge CM1 CM2 CM3 CM3 CM3 CM4 CM4 CM4 CM5 CM5 4. Low oil level CM2 CM2 CM3 CM3 CM4 CM4 CM4 CM5 CM5 CM6 5. Wrong oil CM2 CM3 CM3 CM4 CM4 CM4 CM5 CM5 CM6 CM6 6. Misalignment CM3 CM3 CM3 CM4 CM4 CM5 CM5 CM6 CM6 CM6 7. Aeration & foam CM3 CM3 CM4 CM4 CM4 CM5 CM5 CM6 CM6 CM6 CONDITION MONITORING ZONES SURVEILLANCE LEVEL CM1 = A plus D Real-time Surveillance CM2 = A or B plus D Daily Surveillance CM3 = A, B or C plus E Weekly Surveillance CM4 = D Monthly Surveillance CM5 = E Bi-monthly Surveillance CM6 = F Quarterly Surveillance CM7 Never Surveillance TEST AND INSPECTION CATEGORIES A = Real-time Sensors B = Daily Field Tests or Inspections C = Weekly Field Tests or Inspections D = Monthly Lab Analysis E = Bi-monthly Lab Analysis F = Quarterly Lab Analysis LUBRICANT FAILURE MODE (LFM) RANkING (Example below) Overall Lubricant Criticality (OLC) Score 100 90 80 70 60 50 40 30 20 10 1. Heat CM1 CM1 CM1 CM2 CM3 CM3 CM3 CM4 CM4 CM5 2. Water Contamination CM1 CM1 CM2 CM3 CM3 CM3 CM4 CM4 CM5 CM5 3. Cross Contamination CM1 CM2 CM3 CM3 CM3 CM4 CM4 CM4 CM5 CM5 4. Aeration CM2 CM2 CM3 CM3 CM4 CM4 CM4 CM5 CM5 CM6 5. Metal Particles CM2 CM3 CM3 CM4 CM4 CM4 CM5 CM5 CM6 CM6 6. Wrong or Defective Lubricant CM3 CM3 CM3 CM4 CM4 CM5 CM5 CM6 CM6 CM6 7. Microdieseling CM3 CM3 CM4 CM4 CM4 CM5 CM5 CM6 CM6 CM6 Figure 2. Surveillance Planning Table for the Machine Figure 3. Surveillance Planning Table for the Lubricant www.machinerylubrication.com | May-June 2014 | 3