One of the biggest causes of machinery failure, just behind failed seals and worn packings, is bearing failure. Bearings are not cheap and they are much more involved in the operation of machinery than most people realise, which is why it is so important that they are well looked after.
Shockingly, over two thirds of pump bearing failures are caused by
incorrect operating conditions, which means that it is within your reach to extend the life of your bearings, keep your machinery running, and save money. Here are some useful tips for doing just that:
Lubricants are vital to the correct working of machinery bearings. They are designed to stop elements from rubbing together and come in a range of viscosities, which are needed to cover all bases, from bearing size to rotation speed.
It is estimated that one third of bearing failures are caused by incorrect lubrication, and this isn’t all that surprising because there are so many lubricants with so many different properties available that it can sometimes be hard to choose the right one and to keep it in prime condition.
One study, for example, found that 0.02 percent of water would cut the life of petroleum-based lubricants by 48 percent. This means that not only is it important to choose a lubricant of the right viscosity, but you must also do all you can to ensure that lubricants are not contaminated.
Aspiration and contamination
Bearings generate heat as they move and this caused air in the bearing housing to expand and leave through any available gaps – usually worn lip seals. When machinery is stopped and the bearings cool down some, this process is reversed and air from outside the machine gets drawn into the bearing housing, bringing in moisture, a process known as aspiration.
Unfortunately, most pumps, particularly older models, are not equipped with effective lubricant protection, but you can make them better by instead using bearing isolators which will top moisture from getting into the bearing housing. This increases the life of your chosen lubricant.
A much simpler thing that you can do to extend bearing life is to carry out regularly oil analysis on your machinery. This will help you to quickly identify any contamination, whether from water, additives, dirt or any other matter, so that you can take swift action, clean things up and get your pump back to its working best.