General Information on Service Units
Function and service life of all compressed air tools depend crucially on the quality of the air and its supply.
The service unit serves as an assembly for the preparation of compressed air in pneumatic systems.
In this process, the compressed air is cleaned by the filter, the pressure is regulated by the regulating unit, and the air is lubricated for other pneumatic components by the lubricator.
In order to operate compressed air tools and components with a long service life and proper function, a dedicated air network is just as important as optimally installed compressed air preparation in the operation, because without an effective service unit and professional air connection, even the best tool is neither functionally reliable nor durable.
Before commissioning, it is important to clean the pipe of welding residues, rust, and dirt. When laying the pipe system, it is recommended to install horizontally running air lines with a slight gradient (approx. 1 percent) in the direction of air flow. Branching should always be upwards from horizontal air lines and never at the lowest point from vertical ones.
In order to supply every compressed air tool with the required amount of air, it is recommended to dimension the minimum cross-sections of the pipe system accordingly.
| Nominal Pipe Sizes | Pipe Inner Diameter | Pipe Cross-Section | |
| Inch | NW | ∅ | mm |
| 1/8 | 6 | 6.2 | 30 |
| 1/4 | 8 | 8.8 | 61 |
| 3/8 | 10 | 12.5 | 123 |
| 1/2 | 15 | 16.0 | 201 |
| 3/4 | 20 | 21.6 | 366 |
| 1 | 25 | 27.2 | 581 |
| 1 1/4 | 32 | 35.9 | 1012 |
| 1 1/2 | 40 | 41.8 | 1372 |
| 2 | 50 | 53.0 | 2206 |
| 3 | 80 | 80.8 | 5125 |
| 4 | 100 | 105.3 | 8704 |
Example: 4 compressed air consumers each with a 1/4" connection (61 mm²) require a minimum supply line cross-section of 264 mm², i.e., a pipe with NW 3/4" (NW 20)
The selection of the size of service units is based on the air flow in l/min required by the consumer. Only then are the connection size and other parameters considered.
The service unit should generally be mounted at eye level and at the shortest possible distance from the consumer. First, the filter must be installed, then the pressure regulator, and finally the lubricator in the direction of flow.