The QX pumps are the 5th generation of Bucher internal
gear pumps, which have proven themselves in thirty years
of service around the world. Numerous improvements have
been made to the straightforward and robust design.
Advances in the manufacturing process have made it possible without making higher demands on individual components to build pumps that are considerably lighter and more
compact.
A new tooth profile, conceived and optimised with the help
of CAE, has yielded another significant reduction in noise
levels. Large sealing areas result in higher efficiencies.
The internal ring gear is supported by a hydrodynamic/
hydrostatic lubrication film, which allows operation at low
viscosities or low and high speeds. QX pumps are therefore
suitable for use with variable speed drives, where they can

1.2 Advantages
Extremely long service life
Volumetric efficiency up to 98%
Suitable for use with variable speed drivers
Can be used with fire resistant fluids (HFB, HFC and HFD
= QXV), fuels, biodegradable and low-viscosity fluids
Certifications by ATEX 2, ABS, DNV, GL, LR, NK, ...
Low flow and pressure pulsations