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Pros and Cons of Automatic Greasing Devices It is well known that wear and friction reduce the lifetime of machines and electrical equipment. For this reason, it is important that they are lubricated regularly with grease or oil. Greasing devices allow this process to be automated. Every year, wear and friction cause damage and repair costs in the billions. This statistic alone shows the importance of frequent lubrication for machines and electrical equipment. For example, a well lubricated drive chain not only has a long life span, but also runs quieter because the grease in the chain joints lowers the noise level. Another benefit is that the motor does not have to compensate for the performance loss caused by friction. A study by the German Federal Ministry of Research and Technology concluded that the energy savings in Germany alone would be as high as US$3-4 billion (€2.5-€3.5 billion) as a result of frequent greasing and the proper selection of greases. An improperly lubricated drive-chain results in wear and tear as well as reduced operating time. This is why proper and regular lubrication is crucial. The alternative is dry running which leads directly to rapid deterioration. Rust, cased by friction, develops in the joints. In addition, the surfaces become rough and groves start to form. All these effects cause the joints to stiffen and ultimately the chain breaks. If the chain is lubricated only once, the deterioration process is delayed until the grease is consumed and then the chain runs in dry mode. If not enough grease is applied, the result is uneven wear and the formation of grooves in a part of the slide. This, combined with increased running temperatures, also causes the grease to change color as a result of the grating and by-products. If optimal lubrication occurs, the joints in the slides are evenly worn and deterioration hardly exists. Te grease color remains the same and the grease is free of impurities caused by erosion or by-products resulting in low wear on the chain. The drive-chain example shows that running machines and accessory parts need regular greasing. This fact also applies to production equipment where the greasing process is largely automatic or has been changed to dry lubrication. However, dry lubrication is only suitable if the lifetime of a machine or accessory is the same as its running time. Basic Points to Consider The rule is that one tries to minimize the maintenance of automated production equipment through central greasing devices or greasing transducers. Furthermore, high quality grease can result in longer storage capability. However, there are a number of different types of automatic greasing systems to consider. The following are some points to take into consideration when choosing the best approach for your application. Greasing transducers have the advantage that the lubricators can be in operation for one year or more without maintenance and that they can be filled with any grease. If they are in operation for more than 18 months, however, the danger arises that the composition of the grease will change and the grease quality will decrease. To achieve even lubrication it is important that the greasing device regulates the amount of grease being dispersed through an electronic circuit. High quality lubricators are equipped with synchronous controls and are able to connect to a control mechanism or a PC through a power relay. It is also important that the greasing devices must be filled correctly in order for them to function well. The grease must be put into the lubricator with no air bubbles. This is only possible if the grease is exposed to a centrifugal force of 1400 revolutions per minute. During this process, the grease thickens and the result is a compact filling. To enable the lubricator to function smoothly one must consider certain points during the installation and maintenance. Improper and careless treatments of the greasing device are among the most frequent causes of production loss. An example of this would be the accidental breaking off of the greasing nipple or exposing the greasing device to temperatures of over 150ºF (65ºC). To ensure that such incidences do not occur, one should install the lubrication device so that a visual check is possible. The advantage of this is that the quality of remaining grease can easily be determined. For this reason it is advantageous to use lubricators with transparent cylinders. As a rule it is much more difficult to check the grease volume in brass containers. The unnoticed breakdown of a greasing device during its run time can result in damaging effects. The exchange of a lubricator of the effort of cleaning a machine so that the grease can be dispenses freely is far less troublesome than when a machine stops being greased altogether. Far worse than these preventative measures are the costs of production loss, which are often higher than the machine/part repair. A Survey of the Basic Types of Greasing Devices Available As noted above, when selecting a greasing device, one should pay close attention to such aspects as user friendliness, simple volume check, as well as the option of linking to a PC or control device. Such a greasing device should be able to send an automated signal indicating the grease volume level to the PC or control device. In this regard there are differences that are especially great when lubrication should take place over a long time. This is often the case with roller-bearings in production equipment. The photo below shows a number of different greasing devices that are available on the market today.
Starting from the left, the first of these is called the stuffed lubricator, also referred to as Stauffer-lube (lubricator a). It greases through the manual turning of the upper lid (which has inner thread). The lubricator is filled with grease by means of a spatula. Continuous refilling is required. The consequent risk here is that this task will be forgotten. The second from the left in the photo is the spring pressure lubricator b. It is equipped with a squeezable steel spring that presses on a plastic piston. The output quantity is regulated through a stopcock or a valve. Long-term lubrication at an even pressure is not possible with such a lubricator and it also must be refilled constantly. The third is the tin lubricator marked with c. It is responsible for pressing out a chemical cell that disintegrates within a certain time period. During this process gas builds up which presses on the grease. Disadvantages are the mechanism's sensitive reaction to temperature fluctuation (with premature emptying or a complete halt) and the fact that it cannot be switched off. Grease consumption and functionality cannot be assessed. The tin lubricator is a product that has a very minimal acquisition cost. It is now being produced as a plastic container. Greasing lubricator d is equipped with a single cell battery drive based on electrolysis. But after sustained use the internal pressure falls because its plastic container starts leaking gas. There is also a high risk of the greasing nipple fracturing. The lubricator is an interesting alternative from a technical point of view, but it is not yet fully developed for long-term rigorous industrial use. A characteristic of the greasing lubricator e is that is combines the two pressure building mechanisms of lubricators 'b' and 'd' (steel spring and single cell electrolysis). That, however, complicates the handling. The same components found in lubricators that have been on the market for longer periods are built into this lubricator. It is evident, then, that clear differences exist between the greasing devices. These differences become especially apparent when comparing simple lubricators with high quality greasing devices. The high quality lubricators are higher in cost but offer more reliability and easier maintenance. Relatively new on the market is greasing lubricator f, which is equipped with a small electric motor (1.5 volt batteries). The pressure is generated through a stroke-spindle. The lubricator sounds like a toy car but it has developed an excellent performance record in trials undertaken in rigorous conditions. It also has a pressure of 5 bar, functions well in extreme cold, and can be recycled. Similar to this is greasing lubricator g, but this greasing device is not programmable and dos not function in extreme temperatures. Given thee limitations, this type is also relatively expensive. The high tech lubricators (lubricators h-j) can be used in different temperatures and climate zones. They are suitable for greasing places that are difficult to access as well as sensitive machine parts. Maintenance-free greasing over a period of one and a half years is possible. They also have the largest number of programmable settings available so the dosage and use period can meet any requirement. The lubricator makes it possible for contents volume to be controlled either visually or through a control or PC. The grease release is adjustable to a desired setting. It is possible to turn the lubricator off, to switch it over, or to interrupt the running time -- all while the lubricator is running. The greasing time can be synchronized with the running time of the machine or equipment. The electronic volume display of the lubricator is standard equipment with a signal transducer. The bayonet top includes a built-in magnifying glass for better visual control of the switches. A Final Word on Know-How Frequent causes for incorrect or insufficient lubrication are personnel shortage as well as ignorance of the proper grease or oil types for particular uses. Machine or equipment damage occurs, resulting in production loss. Lack of knowledge is also partly responsible for certain machine parts being over-lubricated. One can optimize lubrication by using a suitable lubrication device. However, an indispensable prerequisite is that the personnel have basic knowledge of the technical attributes of current oil and grease types. Unfortunately, the specialized knowledge of friction, lubrication, and wear is insufficient in many businesses.
125 Unit 475 Unit EM Unit Low-Cost Unit Central Lube | |||||||
