Flow monitor for monitoring the oil flow
Monitoring the volume flow in lubrication systems is an important task for controlling the proper functioning of the system. Central lubrication systems generally supply a large number of different locations with lubricant. The amount of lubricant is precisely defined for each point and must be adhered to exactly in order to ensure the function of the machine or system. The volume flow must meet the requirements both in the main line between the pump and the distributor and in the secondary lines between the distributor and the consumer. If secondary distributors are used, the sections between the main and secondary distributors must also be monitored.
In addition to flow monitors, flow sensors and pulse generators are used to monitor the volume flow. Flow monitors are used either in the main line between the pump and the distributor element or in front of the lubrication point and are available in different versions. Flow sensors are installed in the line between the metering element and the lubrication point if small amounts of oil are dispensed intermittently. When monitoring oil and air lubrication systems, special streak sensors are also used to check the required continuity of the flow. The devices used are part of the periphery of the lubrication system and each act as a pulse generator. This means that to transmit the measured flow volume, electric pulses are generated and passed on.
Technical details on flow monitors and flow sensors
Various considerations play a role when deciding on a particular flow switch or flow sensor. On the one hand, it is crucial whether the lubrication system is a continuous or intermittent operation. Intermittent lubrication systems such as progressive systems are characterized by the fact that the distributor gradually provides the defined amount of lubricant and that there is no continuous lubrication. In addition, the amount of lubricant to be monitored, the effective viscosity of the lubricant and the system pressure must be taken into account.
Flow monitors such as the models 171-210-05x and 171-210-06x are each suitable for monitoring oil systems with a viscosity between 20 and 1,000 mm²/s. The model 171-210-05x is able to guarantee a flow rate between 50 and 1,800 cm³ per minute, with the 171-210-05x the volume flow is between 1.6 and 14.0 liters. Both models are suitable for pressures from 4 to 25 bar at temperatures between +5 and +80°C and are therefore predestined for use in circulating oil lubrication systems such as the SKF CircOil. The sister model of type 171-100-011 also belongs to the group of flow monitors and is particularly suitable for single-line central lubrication systems of type SKF MonoFlex. The flow rate for this type is between 0.2 and 1.5 cm³ of oil per stroke.
The GS300 model, on the other hand, belongs to the class of flow sensors and can be used with viscosities of 10 to 2,000 mm²/s. A quantity of 0.01 to 0.06 cm³ of oil flows through the device per pulse, which produces a maximum of four pulses per minute. The GS3000 pulse generator can be used at pressures of up to 40 bar and temperatures between 10 and 50°C.
For particularly small volume flows in oil-air lubrication, the models GS4011 and GS6011 are suitable, for example, which allow a dosage of 2 to 600 mm³ per hour.