Screw Compressor
It is no coincidence that a truck manufacturer declares the screw compressor in the video below. If one should make a ranking order for
production cars, the turbocharged passenger car with gasoline engine has the fewest, the car diesel a higher and the truck diesel the highest
pressure requirements.
A turbocharger meets the requirements of a high boosted diesel engine very well. But should it be a compressor with its known advantages,
such as already to charge early at lowest speeds and if they have to be changed quickly, the screw compressor is the best choice. In
comparison to a Roots blower it reaches in normal operation up to three times the pressure.
| Small tolerances important. |
It is available with one to three shafts, but interesting compared to the Roots blower is only the version with a main and an auxillary rotor, the former with a more convex, the latter with concave
profile, not necessarily with the same number of recesses, dry and running in oil. With its maximum reachable pressure it can not compete with the piston compressor, but otherwise, it has a wide
operating range.
The screw compressor is said to work with internal compression. For this the pressure ratio between inlet and outlet openings is not so
important as the continuous decreasing of the void space between the two rotors. 05/16
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