Prestressed universal rolling mill
AssigneeNippon Kokan Kabushiki Kaisha
InventorKeiichi Aramaki
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Abstract
There is provided a prestressed universal rolling mill of a type in which a housing is divided into three parts, i.e., an upper cross beam carrying a top horizontal roll, an intermediate frame carrying vertical rolls and a lower cross beam carrying a bottom horizontal roll, and these three parts are clamped together by means of tension bars, whereby after the clamping force on the housing has been released, the tension bars are rotated to simultaneously move the upper and lower cross beams the same distance in different directions, thereby making it possible to readily adjust the position of the top and bottom horizontal rolls and making the construction of the roll stand itself compact and rigid.
Claims5
A prestressed universal rolling mill of a type in which a roll stand for supporting a top horizontal roll, a bottom horizontal roll and vertical rolls is divided into three parts composed of an upper cross beam, a lower cross beam and an intermediate frame and tied together by a plurality of tension bars, characterized in that said tension bars are adapted so that said three parts of the roll stand are bound together by said tension bars with each thereof being elongated by the application of a hydraulic pressure and thereafter said hydraulic pressure is removed to apply a prestressing force to said roll stand, each of said tension bars is rotated within a hole provided in said housing to permit an easy adjustment of the clearance between said top and bottom horizontal rolls, said tension bars are simultaneously actuated from a single source of power, each of said tension bars includes a pair of nuts respectively mounted on the upper and lower portions of said tension bar extending through said hole in said intermediate frame, each of said nuts having threads formed on the inner surface thereof, a pair of thread rings each thereof having external threads adapted for engagement with one of said nuts and an internal surface adapted for loose fit on said tension bar, each of said thread rings adapted to be rotated by said tension bar by means of a stud key mounted thereon, a third externally threaded thread ring mounted on the upper end of said tension bar, a cylindrical nut having internal threads adapted for engagement with the external threads of said third thread ring and a worm wheel formed on the outer surface thereof, a worm adapted for engagement with said worm wheel, a thrust bearing fitted in said lower cross beam to restrain the longitudinal movement of said tension bar, said threads of said pair of thread rings are opposite in direction and of the same pitch as the other, and said threads of said third thread ring are in the same direction as the threads of said lower thread ring of said pair of thread rings and of a pitch two times the pitch of said threads of said pair of thread rings.
A prestressed universal rolling mill of a type in which a roll stand for supporting a top horizontal roll, a bottom horizontal roll and vertical rolls is divided into three parts composed of an upper cross beam, a lower cross beam and an intermediate frame and tied together by a plurality of tension bars, characterized in that said tension bars are adapted so that said three parts of the roll stand are bound together by said tension bars with each thereof being elongated by the application of a hydraulic pressure and thereafter said hydraulic pressure is removed to apply a prestressing force to said roll stand, that each of said tension bars is rotated within a hole provided in said housing to permit an easy adjustment of the clearance between said top and bottom horizontal rolls, and that said tension bars are simultaneously actuated from a single source of power, said mill further including means for supplying said hydraulic pressure to each said tension bar, said means including the body portion of said tension bar having a closed top, an elongated internal hole and a hydraulic cylinder provided at the lower end of said tension bar, the lower structure of said tension bar including an upper portion providing a cover for said hydraulic cylinder, a central portion in the form of a hollow splined rod for hydraulic pressure and a swivel joint connected to the lower portion thereof for introducing hydraulic pressure, a piston mounted in said hydraulic cylinder and adapted to be forced up by said hydraulic pressure, and a compressed bar movably mounted in said elongated hole of said tension bar with the lower end thereof in abutting engagement with said piston so that the upper end of said compression bar forces upward said closed top of said tension bar body portion when said piston is forced up by said hydraulic pressure.
A prestressed universal rolling mill of a type in which a roll stand for supporting a top horizontal roll, a bottom horizontal roll and vertical rolls is divided into three parts composed of an upper cross beam, a lower cross beam and an intermediate frame and tied together by a plurality of tension bars, said tension bars having disposed thereon an upper thread ring and a lower thread ring being located at the top and bottom surfaces respectively of said intermediate frame, said tension bars are adapted so that said three parts of the roll stand are bound together by said tension bars with each thereof being elongated by the application of a hydraulic pressure and thereafter said hydraulic pressure is removed to apply a prestressing force to said roll stand wherein the improvement comprises that each of said tension bars is rotated within a hole provided in said three parts to permit an easy adjustment of the distance between the upper surface of said upper thread ring and the lower surface of said lower thread ring, and that said tension bars are simultaneously rotated from a single source of power.
Dependencies are inferred from the claim text.