Patent ID: 7765901
Filing Date: 2010-08-03
Classification: B23D,Y10T

Abstract:
1. A method for cutting off a thick-walled pipe, wherein the pipe to be cut comprises an inner circumference closer to the longitudinal axis of the pipe and an outer circumference further from the longitudinal axis of the pipe, the method comprising: bringing the cut-off point of the pipe to the cut-off point of a sawing unit, locking the pipe in its place by means of a fastener, sawing the pipe at the cut-off point by moving a saw of the sawing unit towards the centre of the pipe, moving at least two saws of the sawing unit during the sawing radially towards the centre of the pipe until blades of the saws pass through the inner surface of the pipe, and rotating the pipe during the sawing with respect to its longitudinal axis by means of a rotating device connected to the fastener until the pipe is cut off, characterized in that the rotating device starts to rotate the pipe before the blades of the saws pass through the inner surface of the pipe whereby, due to the rotating of the pipe, the blades of the saw work the pipe during a blade revolution only in one direction, which is directed from the outer circumference towards the inner circumference.