An arrangement for continuous making of a pipe insulation section of mineral wool, said arrangement comprising: - a core having an external surface for defining the shape of the internal surface of a pipe insulation section to be made - means whereby mineral wool is capable of being placed against the external surface of the core - curing means whereby the pipe insulation section to be made is capable of being cured to its substantially tubular shape, - pleating means (8, 9, 10 or 8', 9', 10') which enable a web of mineral wool to be pleated into a mat to desired width and thickness, such that each pleat folds up at least partially on top of the preceding pleat - a first blade, which is present on the external surface of the core and extends in the direction of its center axis and in its radial direction and which has two opposite and parallel planar main faces, and that the means whereby mineral wool is capable of being placed against the external surface of the core consist of bending means (18, 20; 13, 33, 23; 44, 14, 34, 24, 54; 45, 15, 35, 25, 55; 47, 46, 16, 36, 26, 56, 57; or 118, 120; 113, 133, 123; 144, 114, 134, 124, 154; 145, 115, 135, 125, 155; 147, 146, 116, 136, 126, 156, 157), by which the mat, produced by pleating, is capable of being bent against and advanced along the external surface of the core and each main face of the first blade over at least a part of the length of the external surface of the core and each main face of the first blade, characterised in that the bending means consist of a belt conveyor which comprises an endless belt and rollers (18, 20; 13, 33, 23; 44, 14, 34, 24, 54; 45, 15, 35, 25, 55; 47, 46, 16, 36, 26, 56, 57), which are installed inside the same and upon which the endless belt circles and which have their reeling shafts lying transversely relative to the longitudinal axis of the core, whereby the number of rollers (18, 20; 13, 33, 23; 44, 14, 34, 24, 54; 45, 15, 35, 25, 55; 47, 46, 16, 36, 26, 56, 57) below the belt in a lateral direction thereof at an upstream end of the belt conveyor is at least one (18, 20) and the rollers in the belt conveyor in a lateral direction of the belt increase in number but decrease in length towards a downstream end of the core, and that, as the rollers (18, 20; 13, 33, 23; 44, 14, 34, 24, 54; 45, 15, 35, 25, 55; 47, 46, 16, 36, 26, 56, 57) present under border areas of the endless belt are, in the traveling direction of the carrier surface of the belt conveyor's belt, adapted in an increasing extent to incline against the belt's edges and the external surface of the core, so that what in the belt conveyor's traveling direction is a left-hand side border area of the belt turns in the traveling direction gradually more and more clockwise against the core's external surface as well as against one main face of the first blade and the belt has its right-hand side border area turning gradually in the traveling direction more and more counterclockwise against the core's external surface as well as against the other main face of the first blade, whereby the belt has its both border areas inclining gradually upwards and closer to each other in such a way that, by means of the belt conveyor, the mat is capable of being first remodeled into an open and gradually deepening trough type shape against and along the core and then at a downstream end of the core, at the latest, into a substantially tubular shape against and along the external surface of the core and the two main faces of the first blade by pressing the mat tightly against the external surface of the core and the two main faces of the first blade while at the same time conveying the mat forward by means of the belt conveyor's belt. - a core having an external surface for defining the shape of the internal surface of a pipe insulation section to be made - means whereby mineral wool is capable of being placed against the external surface of the core - curing means whereby the pipe insulation section to be made is capable of being cured to its substantially tubular shape, - pleating means (8, 9, 10 or 8', 9', 10') which enable a web of mineral wool to be pleated into a mat to desired width and thickness, such that each pleat folds up at least partially on top of the preceding pleat - a first blade, which is present on the external surface of the core and extends in the direction of its center axis and in its radial direction and which has two opposite and parallel planar main faces,