An experimental investigation of abrasive suspension flow machining of injector nozzle based on orthogonal test design

The application of abrasive suspension flow machining (ASFM) to grind a diesel engine injector nozzle is discussed in this paper. The purpose is to remove the sharp corners of the spray holes and improve the fuel flow through the injector nozzle. The proposed method adopts one-way flow to grind the spray holes for high-efficiency production. Compared with traditional reciprocating flow grinding methods using abrasive pastes, the viscosity of slurry and abrasive concentration of ASFM are lower, better for more smooth flow. To achieve a good grinding performance, it is important to determine proper viscosity and concentration. For this purpose, a design of experiments (DoE) method is adopted. In this paper, an orthogonal test method is combined with a non-linear regression method to optimize the process parameters. Through a range analysis on experiment results, the optimal process conditions in terms of the grinding efficiency and the grinding quality are determined. Experiment verifications show that the optimized process parameters can significantly improve the ASFM grinding efficiency and grinding quality.