Abstract: In the perforation of sheet material including leather, artificial leather, foam, paper, filter paper, cardboard and foils by at least one group of spikes with perforating spikes, the individual pieces (9) of the sheet material are held on an endless conveyor device (2) and are pulled off the perforating spikes by a hold-down band (10a) which moves synchronously with the conveyor. It is especially advantageous that the at least one group of spikes is in each instance formed by a spike roller (7) and the hold-down band (10a) passes synchronously with the pieces (9) through the roller gap (8) of the at least one spike roller (7).

Abstract: A linear gas burner for the heat treatment of webs of material has at least one feed line for fuel gas and a long, hollow body, in one of the long sides of which a series of burner nozzles is provided. To equalize the length of the flames and to avoid useless excess lengths or burner at the two sides of the material webs, the hollow body is divided in its longitudinal direction by a baffle into a low-pressure space and a high-pressure space, into which the feed line for the fuel gas opens. The baffle has openings for the passage of the fuel gas, which flows into the low-pressures space in front of the burner nozzles.