Single-line metering devices for central lubrication
Single-line metering devices are a central component in single-line systems for the central lubrication of small and medium-sized systems and machines. Such systems for consumption and loss lubrication serve to compensate for evaporation and aging-related lubricant losses and are characterized above all by the very precise meterability of the lubricant.
The technical basis of central single-line systems is an intermittent, usually time or machine cycle dependent supply of lubricant to several points. To do this, a single line pump builds up pressure and pumps lubricant into the lubrication system using a main line. The single-line or piston metering device is then responsible for distributing the volume flow to the individual lubrication points. A dosing element at each of the metering device outputs ensures that each point receives exactly the required amount of lubricant. The grease or oil is then forwarded to the intended locations in the system via lubrication point lines. In addition to machine tools and packaging machines, typical applications include escalators, compressors or wind turbines.
Technical basics for piston metering devices and single-line metering devices
Single-line metering devices for MonoFlex single-line systems are available in different versions. The primary task of the distributors is the precise metering and allocation of the lubricant as part of an intermittent operation. Depending on the application, the piston metering devices can distribute a flow rate of 0.01 to 0.15 cm³ of lubricant per stroke and have two, three or even five outlets per metering device. Each outlet is responsible for a permanently assigned lubrication point.
In general, a distinction is made in the case of single-line metering devices between prelubrication metering devices, relubrication metering devices and pulse metering devices. Prelubrication metering devices are mainly used in central lubrication systems with high back pressures and systems with long lines. The lubricant is fed to the designated places during the pressure build-up of the inlet pump. In the case of relubrication metering devices, on the other hand, the oil or grease is only pumped after the pump has been switched off, in order to supply heavily loaded areas only after relief. Classical applications are systems with slide guides, such as grinding machines. Pulse metering devices, on the other hand, are suitable for applications in which the lubricant has to be pumped in a very short time. These metering devices are used primarily for chain lubrication.
The single-line metering devices for MonoFlex single-line systems are available in many different versions. One of the entry-level models, the AB product range, is suitable, for example, for the lubrication of a dosing point with a relief pressure of up to 3 bar and a dosing of up to 0.6 cm³ per stroke.
With the VR product series, on the other hand, up to 12 digits can be supplied with a dosage of 1.3 cm³ per stroke. Both variants belong to the class of prelubrication metering devices. Suitable models are also offered in the area of relubrication metering devices and pulse metering devices with the VN or 370 product series.
Advantages of piston metering devices in single-line lubrication systems
Single-line systems with piston metering devices can be dimensioned relatively easily. When selecting the metering device, the number of lubrication points, the required dosage and the lubricant (oil or grease) play a major role.
The operation of a central single-line lubrication system is uncomplicated and is characterized by low maintenance and simple monitoring. Thanks to the modular principle, the system can be expanded very easily if the number of lubrication points changes subsequently.