Contactless application of grease and oil
Precise metering from distance
The contactless application of lubricants meets all conditions for complex, automated production processes and is now standard in many industries. We present the options available and what needs to be considered in the design of the metering system.
Today, the limitations of dot application or continuous application in bead form are quickly reached. Lubricants often have to be applied in hard-to-reach places. This is the case, for example, in the automotive industry, where grease has to be applied to components after they have been assembled, as well as in other industries such as the furniture and household appliance industries. Here, contactless greasing in the form of shot or spray application is often the only option.
Contactless material application offers numerous benefits: precision, speed, reproducibility, reliability and documentation. With contactless material application, the lubricant is applied to the component from a set distance. Regardless of the positioning of the valve on the axis, for example, shots can be set with 100 per cent accuracy with a shot or high-speed valve, even from distances of up to 120 millimetres. The shot valve can perform up to 200 switching cycles in a second with minimal amounts of material. Both valves apply the material in dot form, with the application taking place in the longitudinal direction of the nozzle. With the shot valve, the shot direction can be varied depending on the extension. The dots can be set individually or overlapping in the form of a bead. Application remains contactless compared to a dot application using a needle metering valve, where lubricant temporarily bridges the gap between the metering valve and the component. Spray valves are ideal for contactless, full-surface application of greases and oils. They are capable of both intermittent and continuous material application. Here, too, the shot direction can be varied depending on the extension.
Contactless greasing is always a solution when the point of use of the valve is not freely accessible.
Thanks to a wide range of extensions, attachments and nozzles, all valves offer a high degree of flexibility. Different distances, shot angles and spray patterns, as well as complex geometries, are possible without any difficulty. Contactless greasing is a good solution when the component in question cannot be greased before the assembly of other parts that subsequently prevent access to the application point or when a long immersion distance has to be bridged. With the shot valve, for example, grease can be applied on two sides simultaneously, while, with the spray valve, 360° application is possible.
Spray valve: spray cone and directions
Whether contactless greasing is suitable and offers advantages over material application with a metering valve should always be checked for the particular application. Both contactless application with dispensing valves and metering valves enable precise metering and clean material application. The nature of the material itself plays an important role in the choice. The optimum combination of material and valve should always be chosen. The main advantage of contactless greasing is the higher frequency and speed of metering. In series production, in particular, a few seconds can be critical and can lead to improved efficiency and greater cost-effectiveness. The valves can be optionally supplemented with various measuring devices for optimum quality assurance and documentation, such as a light barrier for shot detection, a gear flow meter, stroke detection or a pressure sensor. This means that process reliability, high quality, and continuous monitoring and control are possible at all times, even with short cycles, high repetition rates and stringently defined tolerances.
The challenges involved in contactless greasing should not be underestimated. The type and consistency of the grease and oil play an important role. Not all types of material are suitable for all valves, for example thin wetting of surfaces with the spray valve. Depending on the nozzle size, materials with different viscosities can be processed with the high-speed and shot valve. In any case, it is important to consider the main criteria involved in the decision process before selecting the metering system. In this way, there are many benefits in terms of speed, precision and material cost savings.