Abstract: The present invention relates to a method of producing mineral wool, mineral raw material (2) is introduced into a melting unit (3), preferably a cupola furnace, for heating the mineral raw material in such a manner that molten mineral material (4) is formed on the bottom of the melting unit, whereafter the molten mineral material is discharged from the melting unit, heated further, and introduced along at least one tapping chute (8, 9) into a spinning machine (10) in which the mineral material is converted into fibre form.

Abstract: The invention relates to a method and a device for producing a mineral wool web from a thin primary web formed on a movable collecting surface (6). According to prior known methods, the primary web is folded on a receiving conveyor (18) in an overlapping configuration so that the desired thickness of web is achieved. It is also known to combine two or several primary webs and to form the final mineral wool web by folding. The problem when producing mineral wool webs is the high rate of production of the primary webs and consequently, the high requirements on the devices in the further process and a great loss of material because of uneven edges which have to be cut down.According to the invention, the primary web is split into separate sheets before the deposit on the receiving conveyor (18), and the sheets are deposited by an oscillating distributing conveyor (16) in an overlapping configuration on the receiving conveyor, or, in case sheets are being produced, stacked on top of each other.

Abstract: A furnace for producing a melt for mineral wool production includes a shaft for preheating and melting of the raw material. A water-cooled grate is disposed in the bottom portion of the shaft, which supports a bed of ceramic filling bodies as well as the raw material. A combustion chamber is disposed underneath the shaft, which has a bottom portion for collecting the melt dripping from the shaft and an outlet for melt tapping. At least one main burner is disposed in the combustion chamber. Auxiliary burners are disposed above the grate. The bottom surface of the combustion chamber is larger, preferably 20 to 400% larger, than the transverse cross-sectional area of the shaft.

Abstract: A pipe insulation sleeve is made of mineral wool bound by a thermosetting binder and comprising an outer insulating layer consisting of a slab of mineral wool hardened throughout, the outer layer having a plurality of radial slits taken out from its inwards-turned surface, which slits run axially and are essentially closed and originally of V-shaped form, and an inner layer of mineral wool bonded to the outer layer by a thermosetting binder and of such thickness and density that it is in itself rigid and at the same time imparts rigidity to said outer layer. The insulating sleeves according to the invention are particularly advantageous when the inner diameter is 300 mm or greater and the thickness is more than 100 mm. A method and arrangement for production of the pipe insulation sleeve is also described.