Abstract: The invention relates to an apparatus (1) for producing a peripheral groove (101) in an end portion (103) of a metal tube (100), in particular a metal tube (100) which is to be coated on the inside, the groove (101) being set up for receiving tube connectors, having a first, rotationally driven roller (3), a second, freely rotating roller (5), the first roller (3) having a roughened or structured surface (6) relative to the second roller (5), a pressing device (15) for producing a relative movement between the first and second roller (3, 5), between a first and a second position, the rollers (3, 5) assuming a first spacing from one another in the first position, which first spacing permits an introduction of a wall of the tube between the rollers (3, 5), and assuming a smaller, second spacing from one another in the second position, which second spacing is smaller than a material thickness (M) of the wall of the tube.

Abstract: A fire extinguishing system including a fluid source, at least one sprinkler (2), and distribution pipes (3). The distribution pipes (3) are formed at least partially as soft-steel metal pipe having a friction loss defined according to the Hazen-Williams formula (1), with P=6.05·105·L·Q1.85·C(?1.85)·d(?4.87), in which P=pressure drop in the pipeline, in bar, Q=flow rate through the pipeline, in l/min, d=average inside diameter of the pipe, in mm, C=constant for the type and condition of the pipeline, and L=equivalent length of pipe sections and pipe fittings, in m. The distribution pipes (3) have an anti-corrosion coating on the inside in order to ensure a value for C in a range of 125 to 150 during commissioning of the fire extinguishing system.

Abstract: A fire extinguishing system including a fluid source, at least one sprinkler (2), and distribution pipes (3). The distribution pipes (3) are formed at least partially as soft-steel metal pipe having a friction loss defined according to the Hazen-Williams formula (1), with P=6.05·105·L·Q1.85·C(?1.85)·d(?4.87), in which P=pressure drop in the pipeline, in bar, Q=flow rate through the pipeline, in l/min, d=average inside diameter of the pipe, in mm, C=constant for the type and condition of the pipeline, and L=equivalent length of pipe sections and pipe fittings, in m. The distribution pipes (3) have an anti-corrosion coating on the inside in order to ensure a value for C in a range of 125 to 150 during commissioning of the fire extinguishing system.

Abstract: A fire extinguishing system including a fluid source, at least one sprinkler (2), and distribution pipes (3). The distribution pipes (3) are formed at least partially as soft-steel metal pipe having a friction loss defined according to the Hazen-Williams formula (1), with P=6.05·105·L·Q1.85·C(?1.85)·d(?4.87), in which P=pressure drop in the pipeline, in bar, Q=flow rate through the pipeline, in l/min, d=average inside diameter of the pipe, in mm, C=constant for the type and condition of the pipeline, and L=equivalent length of pipe sections and pipe fittings, in m. The distribution pipes (3) have an anti-corrosion coating on the inside in order to ensure a value for C in a range of 125 to 150 during commissioning of the fire extinguishing system.

Abstract: A fire extinguishing system including a fluid source, at least one sprinkler (2), and distribution pipes (3). The distribution pipes (3) are formed at least partially as soft-steel metal pipe having a friction loss defined according to the Hazen-Williams formula (1), with P=6.05·105·L·Q1.85·C(?1.85)·d(?4.87), in which P=pressure drop in the pipeline, in bar, Q=flow rate through the pipeline, in l/min, d=average inside diameter of the pipe, in mm, C=constant for the type and condition of the pipeline, and L=equivalent length of pipe sections and pipe fittings, in m. The distribution pipes (3) have an anti-corrosion coating on the inside in order to ensure a value for C in a range of 125 to 150 during commissioning of the fire extinguishing system.

Abstract: A fire extinguishing system including a fluid source, at least one sprinkler (2), and distribution pipes (3). The distribution pipes (3) are formed at least partially as soft-steel metal pipe having a friction loss defined according to the Hazen-Williams formula (1), with P=6.05•105•L•Q1.85•C(?1.85)•d(?4.87), in which P=pressure drop in the pipeline, in bar, Q=flow rate through the pipeline, in l/min, d=average inside diameter of the pipe, in mm, C=constant for the type and condition of the pipeline, and L=equivalent length of pipe sections and pipe fittings, in m. The distribution pipes (3) have an anti-corrosion coating on the inside in order to ensure a value for C in a range of 125 to 150 during commissioning of the fire extinguishing system.

Abstract: A method for coating a pipe (1) in the interior thereof, wherein the method has at least the following method steps: (i.) providing an immersion basin (2) which is filled with a coating liquid (3); (ii.) first immersion of the pipe (1) to be coated into the coating liquid (3); (iii.) first removal of the pipe (1) to be coated from the coating liquid (3) ensuring an angle (?) between the central axis (M) and the surface of the coating liquid (3) with 1°<(?)<30°; (iv.) second immersion of the pipe (1) to be coated into the coating liquid (3); (v.) second removal of the pipe (1) to be coated from the coating liquid (3) ensuring an angle (?) between the central axis (M) and the surface of the coating liquid (3) where ?30°<(?)<?1°.