What is an automatic oil lubrication system?
An automatic or centralised oil lubrication system is a lubrication system that is able to simultaneously lubricate multiple lubrication points of a machine with the correct amount of oil. Automatic oil lubrication systems are particularly suitable for lubricating the slideways, lead or ball drive screw nuts, and other lubrication points of machine tools.
A cyclically operated, single line resistance (SLR) lubrication system is an example of a automatic oil lubrication system. This is a popular type of automatic oil lubrication system that is particularly suitable for use on machine tools. A lubrication system of this type includes a pump and several meter units. A distribution system comprising tubing and various fittings, connects the pump to the meter units. The distribution system also connects each meter unit to a respective lubrication point of the machine on which the lubrication system is installed. The pump is operated in a cyclical manner at predetermined intervals of time so that oil is periodically forced through the meter units to the lubrication points.
The meter units serve to distribute oil amongst the lubrication points in the correct proportions. The amount of oil that can flow through a meter unit is determined by the flow rate of the meter unit. Connecting each lubrication point to a respective meter unit that has an appropriate flow rate allows the correct amount of oil to be pumped to each lubrication point.
When designing a single line resistance, automatic oil lubrication system, it is essential to accurately calculate the particular lubrication requirement of each lubrication point that is to be lubricated by the system. The flow rates of the system’s meter units must then be carefully selected to ensure that each lubrication point is connected to a meter unit that has an appropriate flow rate.
Why install an automatic oil lubrication system?
If a machine tool is not fitted with an automatic oil lubrication system, each lubrication point of the machine must be lubricated manually. Typically, this is done using an oil can and/or a brush. When lubrication is performed manually, it can be extremely difficult, if not impossible, to ensure that each lubrication point receives the correct amount of oil.
Also, although each lubrication point of a machine tool has a partricular lubrication requirement that is typically expressed in terms of cc.’s of oil per hour, it’s usually the case that this amount of oil must not be applied to the lubrication point all at once. Instead, the oil must be applied in smaller quantities at predetermined intervals of time over the course of an hour. It’s not difficult to imagine that manually lubricating multiple lubrication points with the correct amount of oil multiple times every hour can quickly become an extremely tedious and time-consuming task.
As a consequence of the need to lubricate each lubrication point with a particular amount of oil at regular intervals, it’s usually not practical to perform this lubrication manually. Consequently, it should come as no surprise that most machine tools that do not have an automatic oil lubrication system and that rely on manual lubrication are not properly lubricated. This means that the lubrication points of most manually lubricated machine tools are under- or over-lubricated.
Both under-lubrication and over-lubrication are undesirable. Under-lubrication is undesirable because it can result in increased friction between moveable parts of a machine. This increased friction can result in premature wear, which can decrease the accuracy of the machine. It can also adversely affect the smoothness of operation of the machine, and increase the forces that are required to operate it.
Over-lubrication is undesirable because in some circumstances it can result in damage to the machine. It usually also results in oil being wasted and creating an unnecessary mess.
Another problem with manual lubrication is that it is usually not possible to manually lubricate a machine while the machine is in operation.
All of the above-mentioned problems can be easily overcome by installing and using an automatic oil lubrication system. Such a system will automatically meter the oil that it applies to each one of a machine’s lubrication points so that each lubrication point receives the correct amount of oil. Also, it will lubricate all of the lubrication points within a matter of seconds, thus taking the hassle out of lubricating the machine at regular intervals. Furthermore, it can lubricate the machine while it is in operation.
In summary, if you want to make sure that your machine tools do not wear out prematurely through under- or over-lubrication, and you want to take the hassle out of lubricating them properly, the installation of automatic oil lubrication systems on your machine tools is a necessity and not a luxury.