Study on the influence of mixing chamber dimensions in abrasive waterjet cutting heads on cutting efficiency

摘要

The cutting efficiency of abrasive waterjet cutting heads is influenced by the dimensions of nozzle, mixing tube, abrasive (kind of abrasive, flow rate and particle size), type of abrasive feeding systems and geometry of the mixing chamber. To evaluate the influence of the dimensions of the mixing chamber on cutting efficiency, kerf and cutting tests are carried out Different diameters and lengths of mixing chambers are used The cutting parameters (pressure, abrasive flow rate and diameter of nozzle and mixing tube) are varied over a wide range to cover most of the occurring applications The test results are compared by roughness of the cutting surface or by depth of kerf. The air flow rate in the abrasive feeding system has a great influence on the limits of working conditions (possible applications). Therefore the air flow rate in the abrasive feeding hose is measured for each mixing chamber over a pressure range of 50 - 350 MPa (7,250 - 50,800 psi) and for several combinations of nozzle and mixing tube by a flowmeter. An effort is made to define a correlation between results of cutting tests, air flowmeter tests and dimensions of the mixing chamber.