Machinery Lubrication

Machinery Lubrication Jan Feb 2013

Machinery Lubrication magazine published by Noria Corporation

Issue link:

Contents of this Issue


Page 51 of 76

Oil Analysis BACK PAGE BASICS WES CASH NORIA CORPORATION SAMPLING is Key to Oil Analysis ACCURACY Oil analysis is perhaps one of the best tools in your arsenal when it comes to determining the health of a machine. The data in the oil not only holds the key to the health of the lubricant but also to that of any wear modes existing in the machines. When you pair this with historical data, you are able to trend these results and better understand what is going on inside the equipment. Many people regard drawing oil samples as an "as time allows" activity and fail to reap the benefits this technology has to offer. It should be taken seriously and be performed with the utmost care and diligence. It is not enough to simply fill a bottle with oil from the system; you must perform this task properly to accurately trend the data you receive back from the lab. The first step to accurately track data from your oil samples is to identify the proper location for an oil sample. Samples should be taken from turbulent or "live" zones within the oil system. Pulling a sample from the drain valve is not an accurate representation of the condition of the machine. Wear particles, contaminants and water settle to the bottom of the sump, thus making this sample full of historical data and difficult to trend as you continue to sample from this location. Oil Sampling Best Practices Bull's-eye Data • Consistent use of documented "best practice" sampling method and "in application" • Live zone sampling "on the run" • Upstream of filters, downstream of machine components • Flushed sampling valves and sampling devices, clean bottles • Sampled at proper frequency cy • Hours on oil recorded and other meaningful inspection and operating details • Report make-up fluid volume added prior to sampling (if any) • Samples forwarded immediately to lab 52 | January - February 2013 | 71% of machinerylubrication. com visitors report equipment at their plant has been modified to include oil sample ports or valves Drop-tube sampling is another method that should be avoided. This involves a vacuum sample pump, a length of tubing and the reservoir of the machine you are testing. With this method, it is challenging to get the tubing into a live zone of the oil and to repeat the exact same test location time after time. This also leads to poor trending of data and skews the accuracy of your sample. Oil analysis data has a wealth of benefits for those who utilize it properly. Modifying your equipment to include sample ports is a must if you wish to accurately trend your oil analysis data. Installing a sample port or sample valve provides a location where you can consistently pull a representative sample of the oil in your systems. The sample valve should be located in a turbulent area of oil flow. This can be found after pumps or in elbows where the oil turns and begins to flow violently. You want to sample upstream of any filters to ensure that you aren't losing any of the valuable data due to filtration. Some systems may have only one sample port. For instance, if you have a gearbox, you should install a sample port with a stainless-steel tube extension so that the end of the tube (where the sample will be drawn from) is close to the gear teeth and at least 2 inches away from any of the walls of the gearcase. When you sample, you then will use the same port and draw oil from the same place every time. This leads to consistent and trendable data. It also makes spotting any abnormalities in the oil very easy. Many systems should have several sample ports. This is where the discussion of primary and secondary sample ports begins. A

Articles in this issue

Links on this page

Archives of this issue

view archives of Machinery Lubrication - Machinery Lubrication Jan Feb 2013