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Rotary Lobe Blowers

The Robuschi Rotary Lobe Blower range has been renovated, focusing on suiting its customer’s requirements. Robuschi provides premium rotary lobe blowers at varying pressures above atmospheric up to 1,000 mbar (g) and for vacuum duties up to 100 mbar (a) along with maximum air flow of 25,000 m³/h. The large number of models, sizes, options, configurations available provides solutions for most industrial applications.They can operate in pressure and vacuum, equipped as a complete package, customized according to technical requirements and providing optimal performance and maximum uptime with consistent quality and reliability in every application.

Functionality of the “Roots” Positive Displacement Blowers

The air flow depends on the position and direction of the rotors. Based on the assumption that the typical installation p provides a constant air flow, and that the rotational direction is dependent on the “roots” blower design.

The basic principle is as follows: the process starts with air flowing from the inlet port into the element chamber. The timed rotation of the rotors against the wall of the chamber creates so-called “ air flow direction”. There is still atmospheric pressure in these chambers.

As soon as the first lobe passes the opening to the pressure side, the system pressure is adjusted. This is called isochoric compression. The rotors seal each other off to the inside, which prevents a change of pressure.

Compression Principle

Positive displacement blowers operate using the isochoric compression principle, also known as external compression. The pressure increase is achieved by intermittently transporting a gaseous medium (e.g. atmospheric air) into a system. By forcing the medium from atmospheric conditions into a system with a given resistance (e.g. a water column, distribution network ), the relevant pressure increase is achieved. The blower will operate at a controlled output level to overcome this resistance.

Positive displacement blowers, comprise two or three conjugate lobe shaped rotors which rotate inside a pre-machined chamber. The chamber is sealed by the rotating rotors. The rotors are synchronized by means of a timing, 1:1 gear ratio, positioned at the end of the shafts. Bearings are positioned externally the compression chamber with an appropriate design lubrication system The drive shafts have labyrinth style oil seals. The lubrication systems is splash in design.


Airmap Compressors Imperial
Airmap Compressors Imperial

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PD Blowers Application

These products are suitable for many different applications, including the following:

  • Food and Beverage

  • Lime and Cement

  • Environmental

  • Wastewater Treatment

  • General Manufacturing

  • Mining

  • Pulp - Paper

  • Plastics

  • Power Generation – Oil & Gas

  • Chemical – Pharmaceutical