Investigations into the hydraulic-pressure augmented deep drawing process

Improvement in formability of tailor welded blanks by application of counter pressure in biaxial stretch forming

“…The weld properties were not considered in the simulations. The coefficient of friction between blank and the punch and blank and the die was taken as 0.23 for conventional stretch forming (Gupta and Kumar, 2006), while in HMSF, the value of coefficient of friction between blank and the die was taken as 0.05 (Thiruvarudchelvan and Wang, 2001). In case of simulations in lubricated conditions, the value of coefficient of friction between blank and the punch was assumed to be 0.125 (Ghosh, 1977).…”

A note on fluid-pressure-assisted deep drawing processes

“…Counter pressure is absent as in hydraulic pressure augmented deep drawing and the draw stress is proportional to the hydraulic pressure [16]. With the small-end and draw punch diameters 10 and 36 mm, respectively, the draw stress can be calculated to be:…”

“…The last technique produces cups with the largest draw ratio (about 6) ever achieved in any cup-drawing process. Fluid-pressure-assisted deep drawing processes include hydroforming [1][2][3][4], hydro-mechanical drawing [5][6][7][8], drawing against hydraulic counter pressure [9][10][11][12], and the recently developed hydraulic pressure augmented deep drawing process [13][14][15][16].…”

Considerations Regarding Multi channel Sheet Hydroforming

“…One of these processes is the sheet hydroforming [12,15]. Different methods have been developed during the years: hydro-mechanical deep drawing [2,3,14], hydroforming with an elastic membrane [4][5][6], counter pressure drawing [7,8], hydraulic pressureaugmented drawing [9][10][11]13]. Studies of these technologies offered information about sheet formability, surface quality, dimensions accuracy, spring-back effect reduction, and part wall thickness uniformity.…”