Field of the invention The present invention relates to a novel method and a novel system for the manufacture of compensator material of a flexible web of material consisting of several lay- ers, e. g. thermally insulating material, gas-tight mem- brane, cover material coated with an elastomer for use in the manufacture of compensators, e. g. for power and heat- ing works.

Prior art Compensators of flexible material for flue ducts in power works and heating works are still custom-made as hand- work. A typical structure of the wall in such a compensa- tor comprises an inmost wire net, a laminate with a bar- rier to the flue gases, a thermal insulation, and an outer layer e. g. with a protective surface of silicone rubber. The compensators are mounted in an interruption in the flue duct with a flange joint, for which purpose the side wall of the compensator is bent at the ends out into flanges with holes for bolts for clamping with the flanges of the flue duct. The entire structure is hand- work right from the construction of the side wall with the various layers, measuring and punching of the holes for the mounting bolts until the compensator is finished.

Object The object of the invention is to facilitate the manufac- ture of compensators of this type.

Summary of the invention The invention provides a method of manufacturing compen- sator material of a flexible web of material consisting of at least two layers, e. g. thermally insulating mate- rial, gas-tight membrane, cover material coated with an elastomer for use in the manufacture of compensators for

flue ducts, typically in power and heating works, said method ensuring a) that various layers of material are fed from a stor- age station so that the layers are positioned on top of each other in the desired layer structure, alter- natively are fed as a laminate, b) that, during the further feeding, the side edges of the resulting web of material consisting of several layers are bent inwardly over one of the sides of the web of material, preferably on the upper side, to form flange reinforcements, c) that the bent side edges are secured to the rest of the web of material, e. g. by sewing, stitching, weld- ing or gluing, and d) that the web of material is cut to the desired length.

The invention also relates to a system for the manufac- ture of compensator material of a flexible web of mate- rial consisting of at least two layers of material, e. g. thermally insulating material, gas-tight membrane, cover material coated with an elastomer for use in the manufac- ture of compensators, e. g. for power and heating works, said system comprising a storage station from which the materials are fed so that they are positioned on top of each other in the de- sired layer structure, alternatively are fed as a lami- nate, side guides configured so that these, when the webs of material are fed, bend the side edges inwardly over one of the sides of the web of material, preferably on the upper side, to form flange reinforcements,

means for securing the bent side edges with the web of material, e. g. in the form of sewing machines, stitching machines, welding or gluing stations, a feeding station for feeding the material, and optionally a station for collecting and optionally also packaging the finished material.

The method and the system enable production of the fin- ished compensator material or wall material for use in the manufacture of a compensator, thereby considerably simplifying the manufacture of a compensator. The manu- facture may be made considerably faster, and moreover a more uniform product and thereby a better and more uni- form quality are obtained. If the positions of the holes are known in advance, these may additionally be made si- multaneously with the production of the compensator mate- rial.

In terms of working environment, the invention is also advantageous, as the workers are not exposed to fibre dust to the same high degree as in the manual processes, released both by punching of holes and handling contact with e. g. the fibres of the glass tissues, which scratch and irritate the skin and can also give respiratory tract disturbances.

For the manufacture of the compensator material in vari- ous widths, the system is constructed such that side guides and the edge securing means are adjustable in the transverse direction, i. e. they may be adjusted to the width concerned of the compensator material.

At the entry end, the individual layers of material are fed over a transverse guide rod with a contact means ar-

ranged in connection with a microswitch, so that the sys- tems stops if a layer of material breaks or gives out.

Of course, the individual layers of material may be fed singly, but it has been found expedient to feed the joined layers as a unit, for which purpose two longitudi- nally movable, transverse jaw beams are arranged at the delivery end of the system. The individual layers of ma- terial may initially be moved in between the jaw beams which are caused to squeeze the material. The beams are then moved forwards in the feed direction of the mate- rial, pulling the material along. The jaw beams are re- leased, i. e. moved away from each other, and return to the starting position, following which they close again around the web of material, which is hereby fed intermit- tently.

After the jaw beams the material may be fed e. g. by means of friction rollers, or a combination of jaw beams and friction rollers.

To stabilize the individual layers of material in a flat state between the side guides during feeding, the web of material is loaded by smoothing wheels or rollers, pref- erably suspended from weight arms. These keep the mate- rial down against the feed substrate and prevent the ma- terial from folding and curling.

The system is provided with a measuring wheel for re- cording the length of the compensator material produced.

The entire system is expediently controlled by a com- puter, and the measuring wheel is connected to the com- puter.

The punching tool comprises a hanger which extends in- wardly over the web of material at the sides of the web.

The lowermost part of the hanger is provided with an abutment across which the web of material is moved. A punching tool, preferably driven pneumatically, is ar- ranged at the uppermost end of the hanger. Controlling the punching tool by means of a computer allows the holes to be punched in a simple manner, as the measuring of these may be skipped. This results in a significant re- duction in the production time, as 30-40% of it is spent on the measuring of the holes in the traditional produc- tion. The lateral position of the holes is determined by moving the punching tool in a lateral direction, and the distance in the longitudinal direction may be controlled by means of the measuring wheel.

The invention moreover relates to a method of manufactur- ing a compensator of the compensator material manufac- tured by the method according to claim 1, by folding the material to the desired shape of the compensator, cutting the compensator material to the desired length, and se- curing the ends of the compensator material to each other.

In a further development of the invention, the system comprises a device for folding the material to the de- sired shape of a given compensator as well as tools for at least joining the ends of the innermost layer and the ends of the outermost layer, the web material having been cut to the desired length in advance.

What may be involved here is the case where the holes have been punched in the material, so that the compensa- tor is finished after the folding and the joining of the ends of the webs of material. Or it may be the case where no holes have been made in the material.

In another further development the system comprises a ma- chine for making holes in the material. This machine com- prises a table with mutually movable securing means for securing a portion of the web of material and means ar- ranged movably along the table and having punching tools for punching the holes in the web of material, said punching tools being also arranged to be adjustable in the transverse direction.

List of figures The invention will be explained more fully below with reference to accompanying drawings. In the drawings: fig. 1 shows a system for the manufacture of compensator material for compensators, seen directly from the side, fig. 2 shows the system of fig. 1, seen directly from above, fig. 3 shows a system for making holes in compensator ma- terial for compensators, seen directly from the side, fig. 4 shows the system of fig. 3, seen directly from above, and fig. 5 shows the system of fig. 3, seen directly from one end.

Description of the example To the far left in figs. 1 and 2 of the drawing a rack 1 for Euro-pallets 2 is shown, on which layers of material for use in the manufacture of the compensator material are stacked in a folded state. In the case shown, there are four stacks 3a-d. Rollers 4a-h, over which the layers of material may be unrolled, are provided at the upper edge of the stacks in the rack. As will appear, the web

is passed from the lowermost left stack up between the two uppermost ones via rollers 4g, 4f and 4b, 4c.

In addition to the rack there is a frame 5 for two rolls of material 6a, b. The rolls are provided on a mandrel 7 which protrudes from a support column 8. Above the rolls of material 6a, 6b there are three guide rollers 9a, b, c over which the layers of material from the stacks 3a, 3b, 3d are passed.

A plurality of rollers 11 are provided on the front end of the machine 10 where the respective layers of material are fed into the machine. The layers of material are joined between a pair of rollers 12, of which the lower roller is stationary, and the upper roller is adjustable for adaptation to the thickness of the joined layers of material. To keep the individual layers of material to- gether, there is provided a load roller 13 which can be pivoted down and keep the layers of material pressed to- gether by its weight. After this there are two side guides 14a, 14b which partly fold a side strip of the web of material thus produced inwardly over its upper side and partly guide the web of material in a lateral direc- tion. The bent side strips (flange reinforcements) form flanges in the finished compensator. The load roller 13 is in contact with the web of material immediately before the side guides to avoid bulges, which might otherwise disturb the passage into the side guides.

As an alternative to the foregoing, the individual layers of material may have been laminated in advance to a web of material, which is fed to the side guides for the bending of the side edges.

After the side guides, a sewing machines 15a, b known per se is provided on each side for sewing the individual

layers of material together in the web of material at its edge. The sewing machines are arranged in guideways so that they may be adjusted in the transverse direction for adaptation to the width of the web of material.

A jaw beam 17, which is driven reciprocally by two air cylinders, is provided after the sewing machines for feeding the web of material 16. The lowermost beam of the jaw beam is stationary, while the uppermost one 17a is operated by an air cylinder 19. A pair of friction roll- ers 20a, b, between which the web of material passes, is arranged immediately after the jaw beam for feeding the web of material. The uppermost roller 20a may be raised and lowered by means of an air cylinder 21 on each side.

After the machine, the finished web of material is fed to a packaging unit 22. This consists of a portal 23 in which a large box 24 for the material may be positioned.

A roller 25, over which the web of material passes, is provided at the top at the end which faces toward the ma- chine 10.

A transom 27 is drivably mounted between the two upper- most side beams 26 in the portal, said transom carrying two friction rollers 28a, b which are arranged above each other and between which the web of material extends. The transom 27 is driven by an electric motor 28 via a chain drive at each side to and fro in the portal. During this operation the material is folded down into the box placed in the portal. The material thus produced may then be fed further on in the production. It will be appreciated that the box 24 as such need not be a box. It may be a frame or merely a pallet if the material is sufficiently pro- tected against toppling over.

The machine 10 may also be provided with punching devices 30 for punching holes in the joined edge on the web of material. The punching device 30 has replaceable punching tools for punching holes of the desired shape. The dis- tance between the holes may be controlled by the stroke of the jaw beam or in that the punching tool is mounted axially movably. To adjust the punching tool to the width concerned of the web of material, the punching tool is arranged to be laterally movable on the machine.

The machine shown in figs. 3-5 of the drawing is intended for punching holes in the edge regions on a web of mate- rial. It may be undesirable for a variety of reasons to punch holes during the manufacture of the web of mate- rial. It may e. g. be a matter of a form of standard width of a web of material where the hole distance is not known until the compensator concerned is to be manufactured.

The machine is configured as a long table 31 on which the web of material is placed. A locking beam 32 is arranged at the right-hand end of the table to secure the web of material at one end, said locking beam cooperating with the table to lock the web of material.

A carriage 34 is arranged on the side members 33 of the table at each end and carries a transverse jaw beam 35 for securing the opposite end of the web of material. The carriage is driven by means of toothed belts or chain drives.

Additionally, the side members 33 of the table have ar- ranged thereon an extra carriage 36 on which a punching tool 37 is arranged on each side. This tool is arranged slidably in that the end of the hanger 38 is secured to a transverse beam 39 with a slide bracket. The holes may be punched by intermittent movement of the carriage along

the table, as the step distance of the carriage is adapted to the desired distance between the holes. To keep the web of material stretched where the punching takes place, the carriage is provided with a dome-shaped plate 40 across which the web of material passes.

It will be appreciated that, if desired, this machine may be arranged in extension of the production system shown in figs. 1 and 2. It will moreover be appreciated that the machine may be developed further to fold the web of material into a compensator. This may be done e. g. by ar- ranging grippers and guide rollers.