Calibrating a flow of a vertical axis tubular body of a fuel injector for a heat engine, comprises mounting a sliding needle in the injector body, injecting an abrasive oil in a hole through a feeding channel, and treating the abrasive oil

摘要

The process for calibrating a flow of a vertical axis tubular body of a fuel injector for a heat engine, comprises mounting a sliding needle in the injector body (10), injecting an abrasive oil in a hole through a feeding channel (30), treating the abrasive oil under a determined pressure, and rinsing the oil residues during which a rinsing product is injected in the injector body through a supply opening. The oil circulates through the injection hole for eroding the peripheral edge of the opening. The heat engine comprises an upper axial end face (18) and a central axial bore (22). The process for calibrating a flow of a vertical axis tubular body of a fuel injector for a heat engine, comprises mounting a sliding needle in the injector body (10), injecting an abrasive oil in a hole through a feeding channel (30), treating the abrasive oil under a determined pressure, and rinsing the oil residues during which a rinsing product is injected in the injector body through a supply opening. The oil circulates through the injection hole for eroding the peripheral edge of the opening. The heat engine comprises an upper axial end face (18), a central axial bore (22) that opens in the end face, an opening (26) for injecting the fuel, and the fuel supplying channel. The opening is arranged in a lower end of the injector body for connecting the central bore with the outside of the injector body. The channel is connected to a central conduit and opens in the upper face by the supply opening. The central conduit is intended to receive a sliding needle between a lower position in which the lower end of the needle seals the injection opening and an upper position in which the injection opening is opened. The manufacturing step is interrupted when the flow of oil is equal to a reference flow. The oil is injected to the channel under a pressure of 10 MPa for sliding the needle towards the raised position. The needle is controlled by sliding so as to carry out an opening and a closing cycle of the injection hole. The needle is made of a material that is capable of resisting the erosion. An independent claim is included for a device.