Abstract: A system and method for producing flat tubes is described and illustrated. The flat tubes can be produced from at least one strip of endless band material having at least one wall part and an inner part formed with corrugations on a roller train provided with roller pairs, with the strip running in a longitudinal direction through the rollers and being shaped. The inner part of the flat tube can be formed with corrugations placed between the shaped wall parts, after which the closure of the flat tube is carried out. Production of the flat tubes can include forming spaced apart band thinning lines running in the longitudinal direction of the strip, and forming corrugation peaks and corrugation troughs at the band thinning lines.

Abstract: A method for manufacturing tubes, in particular for heat exchangers, composed of endless ribbons on a roller mill, wherein the tubes are composed of at least two ribbons which are subjected to a shaping process on the roller mill, wherein perforations or predetermined break points are introduced into the ribbons at predetermined locations, wherein a step of making the perforations in the ribbons is carried out, after which the ribbons are combined to form the tube and after which individual tubes are separated off at the predetermined locations. The formation of the perforations or the predetermined break points in at least one of the two ribbons is performed within or at the end of the shaping process of the corresponding ribbon so that some of the pairs of rollers do not require a drive.

Abstract: A number of flat tubes, flat tube heat exchangers, and methods of manufacturing both are described and illustrated. The flat tubes can be constructed of one, two, or more pieces of sheet material. A profiled insert integral with the flat tube or constructed from another sheet of material can be used to define multiple flow channels through the flat tube. The flat tubes can be constructed of relatively thin material, and can be reinforced with folds of the flat tube material and/or of an insert in areas subject to higher pressure and thermal stresses. Also, the relatively thin flat tube material can have a corrosion layer enabling the material to resist failure due to corrosion. Heat exchangers having such flat tubes connected to collection tubes are also disclosed, as are manners in which such tubes can be provided with fins.

Abstract: A number of flat tubes, flat tube heat exchangers, and methods of manufacturing both are described and illustrated. The flat tubes can be constructed of one, two, or more pieces of sheet material. A profiled insert integral with the flat tube or constructed from another sheet of material can be used to define multiple flow channels through the flat tube. The flat tubes can be constructed of relatively thin material, and can be reinforced with folds of the flat tube material and/or of an insert in areas subject to higher pressure and thermal stresses. Also, the relatively thin flat tube material can have a corrosion layer enabling the material to resist failure due to corrosion. Heat exchangers having such flat tubes connected to collection tubes are also disclosed, as are manners in which such tubes can be provided with fins.

Abstract: A method for manufacturing tubes, in particular for heat exchangers, composed of endless ribbons on a roller mill, wherein the tubes are composed of at least two ribbons which are subjected to a shaping process on the roller mill, wherein perforations or predetermined break points are introduced into the ribbons at predetermined locations, wherein a step of making the perforations in the ribbons is carried out, after which the ribbons are combined to form the tube and after which individual tubes are separated off at the predetermined locations. The formation of the perforations or the predetermined break points in at least one of the two ribbons is performed within or at the end of the shaping process of the corresponding ribbon so that some of the pairs of rollers do not require a drive.

Abstract: A number of flat tubes, flat tube heat exchangers, and methods of manufacturing both are described and illustrated. The flat tubes can be constructed of one, two, or more pieces of sheet material. A profiled insert integral with the flat tube or constructed from another sheet of material can be used to define multiple flow channels through the flat tube. The flat tubes can be constructed of relatively thin material, and can be reinforced with folds of the flat tube material and/or of an insert in areas subject to higher pressure and thermal stresses. Also, the relatively thin flat tube material can have a corrosion layer enabling the material to resist failure due to corrosion. Heat exchangers having such flat tubes connected to collection tubes are also disclosed, as are manners in which such tubes can be provided with fins.

Abstract: A number of flat tubes, flat tube heat exchangers, and methods of manufacturing both are described and illustrated. The flat tubes can be constructed of one, two, or more pieces of sheet material. A profiled insert integral with the flat tube or constructed from another sheet of material can be used to define multiple flow channels through the flat tube. The flat tubes can be constructed of relatively thin material, and can be reinforced with folds of the flat tube material and/or of an insert in areas subject to higher pressure and thermal stresses. Also, the relatively thin flat tube material can have a corrosion layer enabling the material to resist failure due to corrosion. Heat exchangers having such flat tubes connected to collection tubes are also disclosed, as are manners in which such tubes can be provided with fins.

Abstract: A system and method for producing flat tubes is described and illustrated. The flat tubes can be produced from at least one strip of endless band material having at least one wall part and an inner part formed with corrugations on a roller train provided with roller pairs, with the strip running in a longitudinal direction through the rollers and being shaped. The inner part of the flat tube can be formed with corrugations placed between the shaped wall parts, after which the closure of the flat tube is carried out. Production of the flat tubes can include forming spaced apart band thinning lines running in the longitudinal direction of the strip, and forming corrugation peaks and corrugation troughs at the band thinning lines.

Abstract: A number of flat tubes, flat tube heat exchangers, and methods of manufacturing both are described and illustrated. The flat tubes can be constructed of one, two, or more pieces of sheet material. A profiled insert integral with the flat tube or constructed from another sheet of material can be used to define multiple flow channels through the flat tube. The flat tubes can be constructed of relatively thin material, and can be reinforced with folds of the flat tube material and/or of an insert in areas subject to higher pressure and thermal stresses. Also, the relatively thin flat tube material can have a corrosion layer enabling the material to resist failure due to corrosion. Heat exchangers having such flat tubes connected to collection tubes are also disclosed, as are manners in which such tubes can be provided with fins.

Abstract: A number of flat tubes, flat tube heat exchangers, and methods of manufacturing both are described and illustrated. The flat tubes can be constructed of one, two, or more pieces of sheet material. A profiled insert integral with the flat tube or constructed from another sheet of material can be used to define multiple flow channels through the flat tube. The flat tubes can be constructed of relatively thin material, and can be reinforced with folds of the flat tube material and/or of an insert in areas subject to higher pressure and thermal stresses. Also, the relatively thin flat tube material can have a corrosion layer enabling the material to resist failure due to corrosion. Heat exchangers having such flat tubes connected to collection tubes are also disclosed, as are manners in which such tubes can be provided with fins.

Abstract: A number of flat tubes, flat tube heat exchangers, and methods of manufacturing both are described and illustrated. The flat tubes can be constructed of one, two, or more pieces of sheet material. A profiled insert integral with the flat tube or constructed from another sheet of material can be used to define multiple flow channels through the flat tube. The flat tubes can be constructed of relatively thin material, and can be reinforced with folds of the flat tube material and/or of an insert in areas subject to higher pressure and thermal stresses. Also, the relatively thin flat tube material can have a corrosion layer enabling the material to resist failure due to corrosion. Heat exchangers having such flat tubes connected to collection tubes are also disclosed, as are manners in which such tubes can be provided with fins.

Abstract: A number of flat tubes, flat tube heat exchangers, and methods of manufacturing both are described and illustrated. The flat tubes can be constructed of one, two, or more pieces of sheet material. A profiled insert integral with the flat tube or constructed from another sheet of material can be used to define multiple flow channels through the flat tube. The flat tubes can be constructed of relatively thin material, and can be reinforced with folds of the flat tube material and/or of an insert in areas subject to higher pressure and thermal stresses. Also, the relatively thin flat tube material can have a corrosion layer enabling the material to resist failure due to corrosion. Heat exchangers having such flat tubes connected to collection tubes are also disclosed, as are manners in which such tubes can be provided with fins.

Abstract: A number of flat tubes, flat tube heat exchangers, and methods of manufacturing both are described and illustrated. The flat tubes can be constructed of one, two, or more pieces of sheet material. A profiled insert integral with the flat tube or constructed from another sheet of material can be used to define multiple flow channels through the flat tube. The flat tubes can be constructed of relatively thin material, and can be reinforced with folds of the flat tube material and/or of an insert in areas subject to higher pressure and thermal stresses. Also, the relatively thin flat tube material can have a corrosion layer enabling the material to resist failure due to corrosion. Heat exchangers having such flat tubes connected to collection tubes are also disclosed, as are manners in which such tubes can be provided with fins.

Abstract: The invention relates to a method for manufacturing tubes, in particular for heat exchangers, composed of endless ribbons on a roller mill, wherein the tubes are composed of at least two ribbons which are subjected to a shaping process on the roller mill, wherein perforations or predetermined break points are introduced into the ribbons at predetermined locations, wherein a step of making the perforations in the ribbons is carried out, after which the ribbons are combined to form the tube and after which individual tubes are separated off at the predetermined locations. The formation of the perforations or the predetermined break points in at least one of the two ribbons is performed within or at the end of the shaping process of the corresponding ribbon so that some of the pairs of rollers do not require a drive.

Abstract: Solid rocket fuels with a low pressure exponent and with little or no sigure comprise high-energy nitramine compounds in an amount of 50-90% by weight, an azide group-containing, high-energy binder system of polymers and plasticizers in an amount of 8-50% by weight and heavy metal catalysts in the form of lead, tin or copper compounds in an amount of 0.5 to 10% by weight.