A method for sawing a metal tube (3) or hollow section using a band-saw machine which has a stationary lower saw part (1) having a saw table (2) for placing and fixing a metal tube (3) to be sawn, and an upper saw part (4) which is movable in relation to the lower saw part (1) and which has a revolving saw band (5). The revolving saw band (5) via a feed motion (13) of the upper saw part (4), which is performed in relation to the lower saw part (1), penetrates the metal tube (3) and, for performing a saw cut, is guided through said metal tube (3). The feed motion is carried out substantially counter to the force of gravity.

An apparatus for detecting the breakage of at least one cutting element disposed in a guide includes at least one sliding piece which is linearly displaceable relative to the guide and which can be connected to the cutting element for holding the cutting element. A force applying element is provided to produce a force on the sliding piece so that if the cutting element breaks, the sliding piece is displaced relative to the guide. A sensor detects such a displacement of the sliding piece relative to the guide. A system having the detection device is also provided.

A method for sawing a metal tube 3 or hollow section using a band-saw machine which has a stationary lower saw part 1 having a saw table 2 for placing and fixing a metal tube 3 to be sawn, and an upper saw part 4 which is movable in relation to the lower saw part 1 and which has a revolving saw band 5. The revolving saw band 5 via a feed motion 13 of the upper saw part 4, which is performed in relation to the lower saw part 1, penetrates the metal tube 3 and, for performing a saw cut, is guided through said metal tube 3. The feed motion is carried out substantially counter to the force of gravity.

A double-saw band saw machine includes a base, a first band saw unit, a second band saw unit, a feeding unit and a clamp unit. When an object to be sawn is located in a sawing area between the first and second band saw units, the first and second motors control the first and second frames to move toward each other along the first axial direction, so that the first and second band saw blades can be used to cut the object to be sawn simultaneously. Hence, the sawing efficiency of the double-saw band saw machine is improved, and the replacement interval for the first and second band saw blades is extended.