Method for testing strength of fuel injector e.g. common rail injector, involves increasing hydraulic closing force of nozzle needle by change in partial regions, while maintaining test pressure to increase total closing force

摘要

The method involves arranging the nozzle element (13) in a high-pressure chamber (17) of injector (11) under test pressure medium. The additional hydraulic closing force is applied to nozzle needle (15) in the direction of sealing seat (24), so that the nozzle needle with sealing seat forms the total closing force from mechanical closing force and hydraulic closing force. The hydraulic closing force of nozzle needle is increased by change in cross section in partial regions (DK,DN,DS), while maintaining the test pressure in order to increase the total closing force.