Abstract: The invention relates to an apparatus for manufacturing a metal pipe. At present, accurately measured, thick-walled pipes to be used as rolls must be manufactured in a plurality of working steps. The manufacture of pipes of accurate diameters is complicated e.g. due to inner stresses in pipe blanks which results in deformations in internal or external machining of pipes. An object of the present invention is to overcome the drawbacks of the prior art.

Abstract: The present invention relates to a sheet cutting apparatus comprising a body; a lower blade provided with a cutting edge and supported on the body; an upper blade provided with a cutting edge and mounted on the body by connecting means so as to be scissorwise movable with respect to the lower blade; as well as support means supported adjacent to the cutting edge of the lower blade below the upper blade. The support means comprises a support plate mounted upon the support means by means of at least three pre-stressed springs fitted along the support means. The springs may be pre-stressed between support plate and support means by means of pull rods. The support means is preferably provided with a power unit for moving the support means upwards and downwards.