DK171905B1 - Method and apparatus for making a mineral bowl tubing for insulation purposes - Google Patents

Description

in DK 171905 B1

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of making a tube bowl of mineral fibers, such as glass, stone and slag fibers, for insulating purposes, whereby a mineral fiber web is wound to form a roller with an axially extending hole and the roller is slit after producing forming an openable tube bowl.

The tube bowls made by such a known method are relatively rigid and therefore cannot immediately be used for insulating bent pipe pieces. It is therefore known to cut away portions of the pipe bowls so as to enable the pipe bowls to be sufficiently bent to be placed on pipe bends.

15 This reduces the insulating capacity of the pipe bowls and requires extra work to insulate pipe systems with bends.

The object of the invention is to provide a pipe bowl 20 which is manufactured in a traditional manner and which has such flexibility that it can easily and without extra work be used for insulating pipe bends.

This object is achieved according to the invention by a method 25 of the kind set forth in the introduction, characterized in that the mineral fiber web is treated in at least one longitudinal zone prior to the winding to form a roll in such a way as to weaken the connection between the fibers in this zone.

In the above treatment of the web prior to the winding to form a roll, in the finished roll areas are produced which, because of the weakening zones being superimposed on each other, give the roll a desired flexibility.

35

The aforementioned weakening of the relationship between the fibers can be achieved in several ways. For example, in the longitudinal zone or zones a compression of the fibers can be made.

DK 171905 B1 2

This can be .ex. is achieved by exerting a linear pressure on it in said zone during the advance of the mineral fiber web.

By using this embodiment, a number of parallel separated attenuation zones are preferably produced, e.g. using an embossing roller formed by a plurality of axially spaced discs. Alternatively, attenuation can be achieved by removing material by milling or cutting.

In those cases where the bond between the fibers of the mineral fiber web is provided by an organic binder contained in the web, the weakening of the bond can be achieved by heating the binder to decomposition temperature, e.g. using gas burners or heat sticks.

The method according to the invention is particularly suitable for use in the production of pipe bowls of mineral fiber webs having a weight of from 40 to 150 kg / m3 for mineral fiber webs of stone fibers and from 40 to 100 kg / m3 for webs of fiberglass.

The mineral fiber web may be formed of rock fibers, glass fibers, slag fibers or other synthetic, inorganic fibers.

The invention further relates to an apparatus for making tubular bowls of mineral fibers for insulating purposes, which comprises means for winding a mineral fiber web in the form of a roller with an axially extending hole and means for slitting the roll to form an openable tubular bowl, which Apparatus is characterized in that it further comprises means for weakening the connection between the fibers of the mineral fiber web in one or more longitudinal zones.

Said bodies comprise e.g. of pressure wheels capable of crushing the fibers of said zones or of gas burners 35 or heat rods.

The invention will then be described in more detail with reference to the drawing, in which DK 171905 B1 3

FIG. 1 is a schematic representation of a plant for carrying out the method according to the invention,

FIG. 2 is a perspective view of the embossing and winding members of the system of FIG. 1, and

FIG. 3 shows a longitudinal sectional view of a pipe bend isolated with a pipe bowl made by a method according to the invention.

10

In FIG. 1 comprises an endless conveyor belt 1 supported by two or more rollers, of which only one, 2, is shown.

A mineral fiber web 3 is advanced by the endless conveyor belt 1 passing the web 3 through a roller set comprising a lower support roller 4 and an upper embossing roller 5. As can be seen in FIG. 2, the embossing roller 5 comprises a plurality of spaced discs 6 disposed on a common shaft 7.

During passage through the roller set 4, 5, a number of parallel linear embossing zones 8 are formed in the web 1 corresponding to the number of disks 6 on the embossing roller 5. The embossing of the mineral fiber web 3 results in a substantial weakening of the web in said zones 8, during embossing. a partial crushing of the fibers occurs.

After leaving the conveyor belt 1, the embossed mineral fiber web 3 is inserted between two rollers 10 and 11, which together with five other rollers 12, 13, 14, 15 and 16, 30 of which one, e.g. 15, connected to non-shown driving means, supports an endless elastic band 17 which is passed around a tube 18, which is connected to non-shown driving means, which serves to wind up the mineral fiber web 3 in roll form.

35

Due to the elasticity of the band 17, during the winding of the mineral fiber web 3, it will become longer, thus allowing a roll 19 of gradually increasing outer diameter to be formed. Alternatively, a non-elastic band and one or more rollers 12-16 may be applied to radially displaceable shafts.

When the roll 19 has reached the desired wall thickness, the winding is stopped and the formed roll is removed from the tube 18, which is then prepared to wind a new roll.

The roll 19 removed from the tube 18 will, after slit 10, form a foldable tube bowl. Due to the fact that axially spaced weakening zones 8 are formed in the pipe bowl, the weakened portion of the pipe bowl can be relatively easily bent and is therefore suitable for insulating a pipe bend 20 as illustrated in FIG. 3. A pipe tube 21, prepared as described above, is placed here on a bent tube 21.

By attaching the tube bowl 21 to the tube bend 20, the parts of the tube bowl which are to form the inner side of the tube bend can be easily compressed while the parts on the opposite side remain largely intact.

Consequently, the tube bowl can easily be adapted to the shape of the tube bend 20.

Claims (6)

A method of making a mineral fiber tube bowl for insulating purposes, whereby a mineral fiber web is wound to form a roller with an axially extending hole, and the roller is slit after forming to form an openable tube bowl, characterized in that the mineral fiber web prior to winding to form a roll, it is treated in at least one longitudinal zone in such a way as to weaken the coherence of the fibers in that zone. Process according to claim 1, characterized in that the attenuation is produced by compressing the mineral fibers in the zone. Method according to claim 2, characterized in that the crushing of the fibers in the weakening zone is achieved by exerting a linear pressure on it in said zone during the advance of the mineral fiber web. The method of claim 1, wherein the mineral fibers in the mineral fiber web are bonded together by a binder, characterized in that the attenuation is produced by heating the binder to decomposition temperature in said zone. Process according to claim 4, characterized in that during its advance the mineral fiber web is subjected to the action of one or more burning gas jets. Apparatus for making mineral fiber tube bowls for insulating purposes, comprising means for winding a mineral fiber web in the form of a roller with an axially extending hole and means for slitting the roller after forming a retractable tube bowl, characterized by It further comprises means for weakening the connection between the fibers of the mineral fiber web in one or more longitudinal zones.