Měření a vyhodnocení porušení nehomogenních materiálů kapalinovým paprskem v tlakové komoře

Import 08/08/2006Prezenční516 - Institut fyzik

Řízení technologických parametrů kapalinového paprsku při porušování materiálů

Import 07/02/2010Prezenční545 - Institut ekonomiky a systémů řízenívýborn

Experimental method for the investigation of the abrasive water jet cutting quality

V článku uvedeno L.M. Hlaváč a I.M. Hlaváčová.The use of the declination angle for a prediction and control of the abrasive water jet cutting quality is presented in the paper. The term declination angle is defined and the method for its measurement is proposed. The relationship between the declination angle and cutting wall quality is explained in the theory resulting from former conclusions of Hashish, Zeng and Kim, Hlaváč and others. Experiments proving the theoretical base were performed. The values of the limit traverse speeds predicted from the theoretical equations were compared with values experimentally determined on selected samples. The data calculated from the theoretical models predicting the appearance of the striations on the cutting walls by cutting head tilting are compared with experiments as well

The model of product distortion in AWJ cutting

V článku uvedeno Libor M. HlaváčThe abrasive water jet (AWJ) retardation inside the cut material, the characteristic phenomenon of the AWJ cutting, causes declination of the kerf sidewalls especially in corners and curvatures. This paper is aimed at a description of the origin of these negative consequences of jet retardation. The model for calculation of the limit traverse speed from both the jet parameters and material properties has been derived using laws of conservation. The equation expressing dependence of the angle between the tangent to the striation curve and the impinging jet axis on the depth of jet penetration into material has been used for evaluation of the product distortion in the cutting process. Proposed model has been applied for setting up the tilting angle of the cutting head during the AWJ cutting process to reduce the product shape distortion. The model was supplemented by geometrical analysis of curved parts of cut trajectories. The resulting equation makes possible to calculate the shift of the jet trajectory at the outlet side of the workpiece from its regular position determined by projection of the trajectory at the inlet side of the workpiece along the jet axis. The model is capable to determine the appropriate tilting angles of the cutting head for compensation of the jet retardation and the taper. The experimental data measured on metal samples seem to be in a good accordance with the proposed model.Web of Science621-416615