Water jet incremental sheet metal forming: pressure distribution analysis

Abstract

Incremental Sheet Metal Forming (ISMF) is a very flexible technology for fast prototyping and small batch production of sheet metal parts. This contribution deals with an innovative variant of ISMF, where instead of a rigid tool a Water Jet (WJ) is used as the main tool. Such a process can be addressed as Water Jet Incremental Sheet Metal Forming (WJISMF). The main aim of this paper is to present the technological window for WJISMF and characterize the attributes of the WJ used as the main tool. A Finite Element Analysis (FEA) simulation of axis-symmetrical, incompressible, turbulent, free surface flow was developed to simulate the impact of a WJ on the impingement rigid surface. Measuring the surface pressure distribution at the interface between the WJ and the impingement rigid surface experimentally validated the FEA simulation. Calculated pressure distributions along the surface are in good agreement with those obtained experimentally.

Investigation of machining performance in high pressure jet assisted turning of Inconel 718: A numerical model

“…With tests from small distances it was found that for averaged nozzle design efficiency factor Á w can be greater than 0.75 (Sajn et al, 2008). As a first assumption in this study, Á w has been considered equal to 1 and thus, the overpressure on the impacted surface P s considered as uniform and equal to the nozzle overpressure P n .…”

“…In the literature, experimental and numerical studies on high speed water jet impact on plane surface (Sajn et al, 2008) showed that overpressure in stagnation point on the surface P s can be calculated from Eq. (4):…”

Investigation of Process Parameters in High-Speed Die-less Water Jet Spin-Forming of Copper Sheets

“…The deformation of the aluminium sheet was analysed by a plane strain theory and it is concluded that the WJ can be used instead of the rigid tools to form the sheets [6]. Jurisevic et al illustrated the pressure and velocity pro les of WJ using two-dimensional nite-element simulation [7][8]. In addition, they introduced laminated supporting tools to increase the accuracy of the WJIF process.…”

A study of incremental sheet forming by using water jet

“…To increase the forming accuracy, Jurisevic et al [14] introduced a laminated tool to support the sheet in the ISF-WJ process, which resulted in forming time reduction and part quality improvement. Aiming to derive the technological window of water jet sheet forming process, Sajn et al [15] carried out numerical modeling and finite element simulation to obtain pressure and velocity distributions, by considering turbulent fluid flow through nozzle and water jet impact on a flat rigid surface. Numerical results were in good agreement with those obtained experimentally to provide an insight of the influence of water jet pressure and water jet nozzle diameter on the process.…”