Sarwat Engineering Company


Robuschi’s Range of Positive Displacement Blowers

Robuschi offers both types of positive displacement blowers. The rotary lobe (capacity up to 25,000 m³/h) and the screw (capacity up to 10.100 m³/h) meet the various needs of customers and their wide range of applications.

Take a look at some applications where Robuschi positive displacement blowers are used: 
  • Wastewater Treatment – Aeration &  Back Washing Sand Filtration 
  • Chemical – Vacuum Processing & Pneumatic Conveying
  • Environmental Services – Sewer Cleaning
  • Cement & Lime – Fluidization & Pneumatic Conveying
  • Resin & Plastic – Processing & Pneumatic Conveying
    Process Gas – Gas Boosting
  • Soil Remediation – Vacuum Extraction & Sparging
    Industrial – Material Vacuuming
  • Chemical – Vacuum Processing & Pneumatic Conveying
  • Milling & Baking – Blending & Pneumatic Conveying
  • Power Generation – Fly Ash Conveying & Aeration
  • Pulp & Paper – Chip Conveying & Process Vacuum
  • Aquaculture – Aeration & Pneumatic Conveying 
  • Rotary lobe blowers with pressure to 1,000 mbar (g), vacuum to 100 mbar (a) & air flow to 25,000 m³/h
  • Wide range of models, sizes, options, and configurations available
  • Optimal performance and maximum uptime with consistent quality and reliability in every application

The range of Robuschi Rotary Lobe Blowers has been reinvented, focusing on delivering exacting customer requirements. 

We launch the new Robox blower unit concept, a cutting-edge solution that can accommodate rotary lobe and screw technologies to provide users with greater choice than ever before in helping meet their industrial air and gas needs.

With the new Robox, the difference between lobe and screw technology is reduced to just a few components. This makes it simpler than ever to change from one technology to another and embraces the ongoing shift in mindset from capital investment to total cost of ownership.

Robuschi rotary lobe blowers are available 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.


Pressure - Vacuum

Tri Lobe Blowers


Three Lobe Rotary Blowers

Pressure up to 1,000 mbar (g) - Vacuum up to 500 mbar  (a) - Capacity up to 25,000 m³/h

RBS Steam


Rotary Lobe Blowers for MVR

Pressure up to 1,000 mbar(g) – Vacuum up to 500 mbar(a) – Capacity up to 13,859 m³/h

Blower Unit 1


Blower Unit (new sizes 3.5 & 4)

Pressure up to 1,000 mbar(g)
Vacuum up to 500 mbar(a)
Capacity up to 10,500 m³h

Robox Aqua Blower for Aquaculture


Rotary Lobe Blower Units for AQUA culture Application
Pressure up to 1,000 mbar (g) - Capacity up to 700 m³/h

CRBS GRBS Blower Package


Table Top Blower Units
Pressure up to 1,000 mbar (g) - Vacuum up to 500 mbar (a) - Capacity up to 25,000 m³/h

Robox Bio&Gas Blower for Biogas


Rotary Lobe Blower Units for Biogas and Gas Applications
Pressure up to 1,000 mbar (g) - Vacuum up to 500 mbar (a) - Capacity up to 2,850 m³/h

CRBIO GRBIO Blower Skid for Biogas


Rotary Lobe Blower Skid for Biogas Applications
Pressure up to 400 mbar (g) - Vacuum up to 500 mbar (a) - Capacity up to 2,850 m³/hRB DV Robuschi Vacuum Blower


Vacuum Blowers
Vacuum up to 100 mbar (a) - Capacity up to 10,500 m³/h

TRB DV Vacuum Blower for Truck


Packaged version of RB-DV complete with noise enclosure

Robox Direct Blower Package Direct Driven


Rotary Lobe Blower Package for Ehnanced Efficiency

Pressure up to 1,000 mbar(g) - Capacity up to 700 m³/h




Vacuum Units Vacuum up to 100 mbar (a) - Capacity up to 10,500 m³/h

RBS AV High Vacuum Blower


High Vacuum Blowers

Vacuum up to 0.001 mbar (a) - Capacity up to 9,400 m³/h

Because of the wide range of models, sizes, options, and configurations available from Robuschi, there is a rotary lobe blower that can provide solutions for most industrial applications. These blowers can operate in pressure and vacuum, and can be equipped as a complete package, with customisation according to specific industrial technical requirements and providing optimal performance and maximum uptime with consistent quality and reliability in every application.

There is a rotary lobe vacuum product for just about any industrial requirement.


Functionality of the “Roots” Positive Displacement Blowers

The air flow depends on the position and direction of the rotors. The typical installation provides a constant air flow, and that the rotational direction is dependent on the “Roots” blower design. As a side note, the Roots blower design is enduring and durable. The rotary positive air blower was designed in the 1850s and patented in 1860 by brothers Francis and Philander Roots and the Roots name has remained as the description of the 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

The performance of the compression principle is as follows. 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 are made up of 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 synchronised by means of a timing 1:1 gear ratio, positioned at the end of the shafts. Bearings are positioned externally to the compression chamber with an oil lubricated system. The drive shafts have labyrinth style oil seals, so called because of the labyrinth of grooves that the oil must pass through. The splash lubrication system uses a fine mist of oil for lubrication.

Our products include vacuum pumps, screw compressors, and lobe compressors, and we can deliver the rotary lobe compressor to meet and exceed your application requirements. Our systems have a reputation for being low maintenance.


Airmap Compressors Imperial



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

How the Robuschi Screw Blower Airend Works?

The Robuschi oil-free  screw blower airend is a positive displacement machine with rotary motion, also known as “helical screw” compressor. 

It delivers constant flow (volume) and variable pressure, which means that at a given speed (rpm), the compressor airend always supply the same amount of air, independently by the pressure variation. 

The screw blower airend consists of a pair of helical profile rotors (one male rotor with 3 convex lobes and one female rotor with 5 concave lobes or “flutes”), contained in a casing. 

The rotors turn in opposite direction maintaining precise alignment by means of timing; meshing they form a series of working chambers between the rotors and the casing wall. 

The gas is sucked from the intake side (suction), trapped between the rotors and the casing (radially) and the cover (axially), transported to the compression side (discharge) where the working chamber shrinks, and compressed.     The internal compression leads to supply a steady, non-pulsating air flow, minimizing vibration and maintenance and maximizing lifetime. 

Due to the fact that there is no oil for sealing (oil-free screw), the rotors have very precise and small tolerances to maintain a very small air-gap between the two in order to guarantee optimal performance without touching each other. 


Watch video on YouTube!


Schraubengebläse Robuschi


The Robuschi Screw Blower Range

The Robuschi screw blower range combines innovative components, cutting-edge design and outstanding efficiency. The result is a very comprehensive choice of screw blowers that includes Robox Screw and Robox Energy series.

The new Robox Screw blower fits the state-of-the-art CDL airend. This patented screw blower is equipped with 3x5 profile rotors designed with wide diameter shafts. This reduces the deformation caused by internal and external loads, and ensures the blower can work efficiently in even the harshest conditions.


Thanks to its exclusive design, Robox Screw ensures low noise with a new canopy concept and improved panels. It has a small footprint that uses up to 11% less space while delivering 20% more air flow. It also provides energy efficiency, easy installation and simple accessibility for service and maintenance.

Robox Energy meets the unique characteristics of the RSW "core" (patent) that uses an innovative motor with permanent magnets and an integrated electrical panel. This offers maximum efficiency, compactness, simple maintenance and flexibility for wastewater treatment plant requirements.

Screw Blower 1


Screw Blower Unit 1


The ROBOX Screw blower unit up to 1,000 mbar(g)


The new Robox blower unit design allows you to fit either a lobe or a screw airend into our engineered Robox enclosure. To accommodate this innovation, our teams performed a complete package redesign. You can call it thinking outside the box to create our best Robox yet.

The Robox Screw is able to reach up to 1,000 mbar(g) and vacuum up to 300 mbar(a) with a maximum capacity of 10,100 m³/h.

Unique design, best in class footprint, low noise, easy installation, easy to service and maintain access throughout the range.

Unique Design, Best-in-class Footprint 

Thanks to its exclusive features, the new Robox Screw blower unit has compact dimensions with the possibility of side-by-side installation. It is easy to be installed with no requirements for ducting. The Robox Screw blower’s compact dimensions will optimise your floor space usage. The new Robox Screw blower unit size 3.5 requires on average 11% less space to deliver 22% more air flow.

Screw Blower Unit4

The Robox Screw blower unit is available in a new plug and play version. It’s simple, reliable and a great value for your money. This includes:

Blower Unit Plug & Play Frequency Converter
  • Premium frequency converter for maximum performance and reliability
  • Electrical cabinet with IP54 protection degree and a forced cooling system
  • Modular installation close to Robox unit or in another location via wired connection for maximum flexibility
  • Programmed control panel for process optimization and regulation
  • Industry 4.0 solution with data transmission through the most popular communication protocols (Modbus, Profibus-Profinet, Canopen)
  • Preset frequency converter for peace of mind
  • Additional system for continuous monitoring of main parameters (optional)
  • Quick start guide included
  • EMC certification



Robox Energy Screw Blower Unit


Screw Blower Unit with Permanent Magnet Motor

Pressure up to 1,000 mbar(g) – Capacity up to 4,200 m³/h

Maximum Energy Efficiency

Superior pump technology, incorporating a permanent magnet motor fitted directly to the conductor shaft, with a wear-free design, prevents any potential loss of power from the belt drive and can realise energy savings of up to 30 per cent, compared to a standard rotary lobe machine. 

Robox Energy Screw Blower

Smart and Flexible

The Robox Energy screw blower is equipped with the latest generation (HMI) “touch screen” control panel. It is user-friendly with an intuitive menu, easy to program thanks to the well-known Windows CE system and can be remotely connected.  The flexibility and versatility of the new Robox screw blower is masterminded by Robuschi’s Smart Process Control tool. It analyses and applies the oxygen data received directly from the process and adjusts the operating parameters accordingly without interrupting the process.

Extremely Compact

Robox Energy requires approximately 30% less space than comparable units. It responds to the growing market for smaller and compact machines in the compressor room. An other advantage of its design is the fact that several units can be placed next to each other with front access for the maintenance.


WATER 4.0 puts digitisation and automation at the centre of the industry strategy, aimed squarely at creating resource-efficient, flexible and competitive water management.

The new Robox Energy screw blower equipped with iConn module delivers just that.

iConn Industry 4.0

iConn provides plant operators with in-depth and real-time data, essential for an optimised and efficient wastewater treatment operation. The remote availability of machine operation data saves time by removing the need for on-site supervision, optimises maintenance and parts management, and paves the way for the development of predictive models.

iConn optimises maintenance, maximises blower reliability and enables customers to focus on their core business.