Compressor plants are widely used in domestic economy, in technical equipment of small workshops and in production facilities. Such equipment allows economically to generate operating effort, in some cases eliminating the need for direct connection of equipment to the power grid. But for the high-quality servicing of the target instrument, it is necessary to initially determine the optimal installation option. At the first stage of selection, the answer to the following question is answered: which compressor is better – oil or oil-free? Both variants are attractive in their own way, but in different operational qualities.
Arrangement of oil compressors
To begin with, it should be noted that both types are part of a common group of reciprocating compressors, also called coaxial ones. This technique is characterized by quite high performance, reliability and versatility of use. But already within the family there are differences between subspecies, which represent oil and oil-free compressors, as well as belt modifications.
So, the oil unit has in the composition of the crankshaft and the piston group, which exerts the necessary force action in conjunction with the drive system. The lubricating liquid is just poured into the crankcase of the crankshaft, after which it is distributed over the elements of the mechanical tooling, ensuring the stability of its operation. Therefore, in terms of ease of maintenance, the question of which compressor is better – oily or oil-free, will be decided in favor of the second option. The lack of regular lubrication level support is particularly sensitive in large enterprises where preventive maintenance is performed after each working session.
Design features of oil-free models
In general, the technical and construction base of such compressors is similar to oil analogs. The basis is represented by the same piston group, power unit, crankshaft, etc. The difference is exactly the approach to the organization of the cleaning system. In the case of oil equipment, air flows intersect with the lubricant supply channels. Conversely, the arrangement and advantages of the oil-free compressor are interrelated and are due to the fact that the lubricating fluid and the air flow pass through different channels. The oil is not poured into the crankcase but is sent to a special cleaning system. Therefore, it can not be said that oil-free coaxial models are completely devoid of lubrication. It is only limited to the design nuances of the filing, in which there are pluses and minuses.
Advantages of oil compressors
The main advantage of the units with a full-scale oil supply is the high resource of the element base. Thanks to effective lubrication, the parts of the same piston group receive a sufficient wear-resistant shell, which increases their durability. At the same time, the user can expect high performance. Massive construction can be used in factories and machine-building industries. However, in such conditions almost any coaxial unit can work – oil or oil-free. Which compressor is better in terms of continuous operation? With this requirement, it is desirable to give priority to oil devices, since they are initially calculated for long working sessions.
Advantages of oil-free equipment
And the alignment of the air channel with the lubricant supply circuit, and the separation of these lines is not an incidental structural consequence, but a fully conscious technical solution. It separates oil and oil-free compressors, as well as their performance. And if the first option gets advantages in the form of increasing the working resource of the structure and increasing the productivity, the oil-free units differ in the quality of their work.
A separate supply of lubricant allows the outlet to give clean compressed air. Therefore, the question as to which compressor is better – oil or oil-free, in terms of the quality of the serviced tool will be decided in favor of the second option.
Comparison of the performance of two compressors
It is not possible to say which option will be optimal in each case. It has already been said that for large plants where the quality of the supplied air does not matter much, it is advisable to use oil equipment. Such a device can meet high demands on load, wear resistance and stability of the working function. Quite differently is the comparison of oil and oil-free compressors in the context of domestic use. In this area, compressors are more often used for servicing spray guns, pneumatic screwdrivers and other devices working in compressed air. And regardless of the purpose of such a tool will be demanding on the quality of the air jet. Accordingly, impurities of the lubricant from the oil compressor are not needed here, and the choice should be made in favor of an oil-free unit.
What else to consider in choosing?
Belonging to this or that type of compressors determines only the direction of the operational potential. In one case – towards reliability and productivity, and in the other – it speaks about the quality of the working function. But also it is necessary to approach in detail to a choice of model on the basic characteristics. What should be the right choice? Oil and oil-free compressors, features, as well as their functional capabilities, are determined by the level of pressure, airflow and volume of the receiver. The pressure is usually from 6 to 10 bar, if it is a question of application in workshops or in small production. The optimum air flow for similar needs should be 200-400 l / min. For domestic tasks in working with a spray gun, you can also limit the compressor to 75-100 l / min. As for the volume of the receiver, In a private farm, models with a tank of 20-30 liters are usually used. Professional equipment for the same long-term work can also have 500-liter containers.
Feedback on the manufacturers of compressors
Compressors are widely represented by the brands Abac, Elitech, Daewoo, Hyundai and FUBAG. These are semiprofessional and professional units, users of which note the high quality of assembly and durability. In the construction segment, the products of Hitachi, Metabo and Sturm are especially appreciated. These manufacturers can be contacted regardless of the type of unit that you plan to buy – whether oil, or oil-free.
The most successful choice will be made in the event that the disadvantages of the compressor does not affect the practice of use. It happens rarely, but it is quite possible. Even if we are talking about a clear deviation from the requirements, the difference can be corrected by an accurate selection of technical parameters. But often there is a need for a universal generator of compressed air. Which compressor is better – oil or oil-free, if you choose a model for a wide range of needs? Specialists still recommend turning to oil-free units, as they are theoretically able to solve the problems of traditional oil models. But as an alternative, it makes sense to consider and belt equipment. This technique is a balanced solution, but requires regular updating of consumables, among which the same drive belt.