Abstract: The invention relates to sail battens comprising tubular batten rods (1) which meet each other in a loose manner and in which tubular inner rods (2) of the same length are arranged to span tubular inner rod joining areas and meet each other in a loose manner. The mutual transverse play (5) of said inner rods determines the arch. To this end an internal support line holds together the arched section and the longer fixed rear rod.

Abstract: A roller, particularly for a roller hearth furnace for heating materials to high temperatures, has a supporting body defining a roller axis and having a curved center line and a cross-section substantially normal to said center line. The supporting body includes a plurality of portions which are connected with one another and radially surround the roller axis in spaced relationship therewith. The portions extend in a circumferential direction and are positioned at axially spaced locations relative to one another so that a periphery of the roller is materially formed only at locations corresponding to the axially spaced locations of the portions and the roller has a plurality of empty regions between these locations.

Abstract: A roller-hearth furnace has workpiece-supporting rollers which are thermally shielded at the sides and from below. Intermediate the rollers the workpieces are exposed to heat action from below.

Abstract: A furnace for heat treating of workpieces includes a workpiece-engaging member mounted on an elongated, internally cooled supporting member for supporting workpieces from below which are to be advanced through and heat treated in the furnace. A ceramic material heat-insulating jacket partially surrounds the supporting member for insulating the latter from heat. A protective arrangement is provided on at least one of said members for protecting the ceramic jacket from damage by a workpiece in the event that a workpiece slides off the workpiece-engaging member.

Abstract: A furnace for the heat treating of workpieces includes an elongated internally-cooled supporting member which supports workpieces which are to be advanced through the furnace and a plurality of workpiece-engaging elements, each having a lower portion mounted on the supporting member and an upper portion which is larger than the lower portion and which has an upwardly-directed planar surface which is adapted to support the workpieces from below.

Abstract: In a furnace for heat treating of workpieces, a workpiece-engaging element which is adapted to support a workpiece which is to be advanced through and heat treated in the furnace is mounted upon a mounting surface of an elongated, internally-cooled supporting member. The supporting member includes a first section having first walls which diverge from each other in direction away from the mounting surface until the first walls define a maximum spacing therebetween. The supporting member also includes a second section adjoining the first section and having second walls which are spaced from each other at a predetermined distance not exceeding the maximum spacing so as to permit heat to flow towards the underside of the workpiece without being screened by the second walls.

Abstract: Burners of an oven are operated to satisfy heat loads changeable between a high load and substantially smaller loads. At least under the smaller loads the burners are cyclically controlled in a cycle of time periods T-1 and T-2. During the periods T-1 the burners are steadily regulated to maintain a uniform temperature in the oven. For periods T-2 the burners are periodically controlled to admit one of two selected magnitudes of fuel flow to the oven. At least under the smallest loads the latter magnitudes are periodically controlled to be zero or close to zero.