External-gear pump / high-pressure
71 - 125 cm³/r, max. 280 bar | KP 3
Thanks to their construction (design principle) and the materials used KRACHT series KP 2/KP 3 external gear pumps are suitable for use under the most stringent operating conditions. The housing and the flange mounting cover (see the sectional drawing) – both made of gray cast iron – have high dynamic load capabilities and are therefore insensitive to peak pressures and permanent oscillations. Large-scale PTFE-Pb coated plain bronze bearings on steel backs in the housing and the flange mounting cover carry the extremely finely ground bearing pins of the gear, which consists of the driving shaft pinion. The tooth profiles of the gear, which is made of case hardened steel, are ground to achieve the best running characteristics. A considerable reduction in the volume flow fluctuation and
thus of the pressure pulsation is achieved through the high number of teeth (z = 14) and in combination with a tooth from shaped in accordance with the special requirements of Description Construction hydraulics and the optimum rating of the expansion grooves in the quench oil area. This leads to much lower noise levels for the pumps, or for complete systems and machines. The function of the axial play compensation that is essential for high pressure pumps is carried out by the sliding plates located at the side of the gear. These have hydraulic pressure fields that guarantee compensation of the axial play on all operating pressures. The sliding plates are designed so that play is compensated inde-pendently of the viscosity. This ensures a high degree of volumetric and mechanical efficiency at every working point.