The column’s author, Michael Holloway, has been involved with maintenance, reliability, and manufacturing for over 25 years. He has spoken at numerous conferences and given hundreds of seminars and lectures on the topic, but prefers to skin his knuckles and get dirty on all sorts of equipment. He can be reached by e-mail at mhollowa@nch.com.
Max, my six-year-old son, was having problems tying his shoelaces. Of course this was right before he was to get into the car to go to school so the anxiety of being late only compounded the problem. It wasn’t until I actually got down on the floor and tried to understand what the problem was that I was able to provide a solution. First off, he had tucked the tongue of his sneaker under his foot as opposed to letting it rest on top. Secondly, he was attempting to loop the ends through and not just tying the loops. It was only after I spent time “on the floor” was I able to understand the problem. I offered up some quick and accurate suggestions that would ease the anxiety and “increase his production rate.” Problem solved; no tardiness. Max is happy, dad is happy, and most importantly, mom is happy.
Problems that occur on the production floor are far more complicated and critical than understanding why a six-year-old is having problems tying his shoelaces. But the idea of actually spending time understanding the problems by direct involvement is critical and beneficial regardless of the machine or application. You have to spend time on the floor with the folks that are actually skinning their knuckles and getting dirty. If not, you will never know what the problems are and how to effectively address them.
The role of the maintenance technician has evolved over the past century. Many years ago, teams would only be relied on to fix a machine when broken. This approach is known as “reactive maintenance.” Even today, this approach is very common mainly because many companies just can’t catch up to do the types of things they know would actually increase reliability and decrease downtime. In many cases, there is not enough time or resources.
Shortly after World War II ended, there was an increase in prosperity. An increase in domestic production of various items followed. The increase in production demands meant that equipment had to produce more in a shorter time. For the first time, the use of electronics was heavily relied on. This had a direct effect on productivity, but it also meant that maintenance technicians had to become quick studies in troubleshooting these devices. Computers (albeit first generation punch-card and reel) were now being used by many of the forward-thinking facilities. Data was stored and analyzed. Manufacturing and maintenance technology in the late 1950s blossomed due to competition, innovation, and the “space race.”
During the space race, the National Aeronautics and Space Administration had to employ a technique called failure mode effects analysis (FMEA). Aerospace technology demanded that equipment failure was not an option. Therefore, when a part broke, the root cause had to be identified and a corrective action (and potential design change) be put in place. This approach was quickly adopted by many factories, including part, tool, and machine manufacturers. FMEA had a direct effect on the bottom line and the quality initiative that many companies were trying to develop. This technique helped users in the next generation of maintenance approaches – “preventative maintenance.”
Preventative maintenance schedules the rebuild or replacement of parts or machines prior to failure. Through recordkeeping it is possible to determine that certain parts will fail after many hours of operation. Scheduled downtime to administer preventative maintenance becomes routine, with various parts being rebuilt of replaced prior to failure. Unscheduled downtime can be reduced dramatically. Using preventative maintenance techniques, the maintenance team contributes to the facility’s efficiency and profitability. Maintenance departments transition from a loss center to a loss prevention center.
As preventative maintenance techniques and practices began to flourish and evolve, the next natural progression would be that a technician attempted to predict equipment failures as well as trying to prevent them. Many years ago, it was not uncommon for mechanics to listen to a bearing or a gearbox with a screwdriver. The mechanic would put the screwdriver handle to his ear and place the tip onto a gearbox, pump, or bearing housing and “listen.” This is a technique I use to this day on various pieces of equipment, including engines. The human ear is especially sensitive to various vibration states and our brains are wired in such a way that we tend to remember variations of different sounds. It is actually rather easy to pick up the slightest amount of grit grinding away at a bearing race or a pump experiencing subtle cavitation. This approach is known as “predictive maintenance and condition monitoring;” when various analytical techniques are done on a regular basis to determine if failure is approaching. Action is taken if eminent failure is possible.
If preventive maintenance is a good diet and exercise, then predictive maintenance and condition monitoring is a check-up by your doctor that includes blood work (oil analysis), listening to your lungs and heart (acoustic and ultra-sonic analysis), taking your temperature (thermal analysis), and a stress test (vibration analysis), just to name a few.
These are only a few concepts that are being implemented with great success. Other concepts such as continuous education, procurement specifications, and plant surveys are also finding great success.
In the months to come, we will take a good hard look at each of the techniques and understand how they can be easily integrated into your maintenance department’s current operating procedures. More importantly, we will learn how to actually track the benefits of the various techniques that will be explored and how to implement a reliability-centered maintenance directive.
Getting Down on the Floor - August 2005 Render