For the patented volume-flow measuring device, the injection nozzle to measure is briefly included in a hydraulic circuit with an energetically favourable hydro-pneumatic reservoir, and the time of the pressure drop between two defined pressures is measured. By means of the adiabatic state equation of the reservoir filled with nitrogen, the quantity of the discharged test oil and the volume flow are calculated and immediately displayed. The needle lift can be adjusted and checked.
The volume-flow measuring device provides for a quick and exact measurement of the most important parameters of injection nozzles. In this new method, the energy storing capacity of a membrane reservoir is utilized. The reservoir is filled by a small liquid pump operated by compressed air, and the required volume flow passes through the nozzle during the short measuring time of approx. 0.5 s, depending on the size of the nozzle. In this way, just about 80 cm3 test oil are needed for one measurement By means of the adiabatic state equation for nitrogen, the quantity of test oil discharged during the pressure drop from 26 to 24 bar can be calculated from the measurement of the temperature and of the pressure. By the additional measurement of the discharge timer, the mean volume flow of the injection nozzle at 25 bar is determined and immediately displayed, standardized to 20°C. Such mean volume flow deviates just at a negligible rate from the measured value at a constant pressure of 25 bar. The measurement can be made on a favourably low pressure level because the test oil has a very low viscosity equal to the one of diesel oil, so that the reduction of the flow coefficient, caused by flow cavitation in the spray bores, is constant at 25 bar already.
Health protection is ensured by a spray protection device and an electrical coupling of the protective door with the measuring valve and the lifting cylinder valve.
Herr Dipl.- Ing. Norbert Krümmling
Phone: +49 34901 883-244 | Fax: +49 34901 883-121