Abstract: In a method for the hydro-erosive rounding of an edge of a part, particularly an edge in a duct of a high pressure-resistant part, and a use thereof, a liquid to which abrasive elements are added is directed along the edge that is to be rounded. In order to optimize the result of the rounding process, a high-viscosity liquid is used as a liquid (10). The inventive method is used for rounding parts of a fuel injection system.

Abstract: A fuel injection valve comprising a nozzle body (8) having a nozzle body seat (18), and a nozzle needle (2) is disclosed which is guided into the nozzle body (8) in a sealed manner and which comprises a nozzle needle shaft (6) and a nozzle needle seat (12). The nozzle body seat (18) and the nozzle needle seat (12) together form a sealed seat (20). A gap (28) is provided between the sealed seat (20) and the nozzle needle shaft (6). An outer surface (25) of the nozzle needle (2) extends in the region of the gap (28) essentially parallel to an inner surface (26) of the nozzle body (8).

Abstract: In order to set the nozzle opening pressure for an injection nozzle, in particular for a diesel injection nozzle, to an accuracy of around ±1%, the method provides that the injection needle is first pressed against the valve seat with a closing force (Fz), and then when two different test pressures (pU, p1, p2) are applied to the injection nozzle the test forces (Fz, F1, F2) effective on the injector needle are measured, with the pressure stage (A) being determined from the measured test forces and the test pressures applied, and finally using the pressure stage (A) a nozzle valve with a suitable valve spring force (Fv) is selected to correspond to the desired nozzle opening pressure (pD).

Abstract: Located between the frustoconical needle tip and the cylindrical needle shank of a nozzle needle of a fuel injection valve is a frustoconical needle portion, into which is introduced a peripheral groove. Through this kind of arrangement damping is capable of being set, depending on the position of the groove, during the axial movement of the nozzle needle.

Abstract: The nozzle body (5) of a fuel injection valve has a central bore (54) in which a nozzle needle (1) is guided. The tip (52) of the nozzle body (5) has a tapered valve seat (55) which forms together with the sealing edge (27) of the nozzle needle (1) a valve (27, 55) which controls the flow of fuel to the injection holes (9) in the nozzle tip (52). Underneath the sealing edge (27) a circumferential groove (33) is disposed in the truncatoconical needle tip (30, 35, 40, 45) at the level of which the injection holes (9) are disposed, so that when the valve (27, 55) opens the nozzle needle (1) is axially stabilized and the shaping of the injected jet is improved.

Abstract: In a nozzle body, a degree of rounding of edges of an entry region of an injection hole duct in the nozzle body is dependent on a distribution of a fuel stream around the entry region. The edges being more rounded, the greater the fuel stream at the respective edge portion is. The entry region of the injection hole duct has, in this case, preferably the form of an ellipse.