AU740716B2 - A method and a device for attaching insulation material on the outside of pipelines - Google Patents

Description

WO 99/18384 PCT/NO98/00300 A METHOD AND A DEVICE FOR ATTACHING INSULATION MATERIAL ON THE OUTSIDE OF PIPELINES The present invention relates to a method and an attachment device for attaching insulation material which, preferably in the form of insulation units such as mats, is placed insulatingly around the outside of pipelines which e.g. may be of the kind included in ventilation plants.

Conventional fastening of such insulation mats which each, preferably, extends one turn around the pipeline, has consisted in taping adjacent end portions of the insulation mats in pairs, so that tape covers the insulation mat joints.

Empirically, it has be found that such tape loosens after some time, resulting in the formation of apertures in the pipeline insulation, causing a deterioration of the insulating properties, simultaneously as particles of the insulation material gradually will be released therefrom and pollute the underlying room.

Known technique dealing with various solutions associated with fastening and fixing insulation units/material, does not solve the above defined problem.

WO 99/18384 PCT/NO98/00300 2 Prior art as represented through patent publications, are elucidated in the following: GB patent specification No. 1,134,432 deals with an insulation layer attached directly to the inner face of a jacket surrounding e.g. a knee. Metal rings are used only in order to achieve a better appearance between one casing and another. GB patent application No. 2,255,818 deals with an insulated pipeline, in which the entire insulation layer is encapsui0 lated within a metal jacket. Some places on this insulated and encapsulated pipeline, have been made available upon the removal of annular metal jackets with insulation and inserted therein divided, semi-circular, insulated insert pieces which may easily be removed and brought into place again by means of easily releasable, mutually co-operating locking means at adjacent ends. Normally, the insulation layer around the inner pipe is very well protected within the fully covering metal jacket. This has no similarity to insulated pipelines in which the insulation is fully unprotected, only kept together at the joint areas by means of tape.

DE 29 10 983, deals with a removable insulation compensator accommodating various expansions in insulation material and pipeline due to temperature increases (the drawings are defective and the specification lacks an explanation of the general structure of the pipeline). However, it seems as if the insulation of the pipeline is encapsulated within a jacket, and that an annular insert is divided and insertable/ withdrawable. The problems sought to be solved according to the invention, recovered where insulation mats were rolled around a pipeline, fixed thereto at the joint places by means of tape, do not exist here.

DE 36 34 347, deals with a device for thermal insulation of the seams between adjacent vacuum heat insulation elements 3 which, at one side, bear against a gas-tight, pressure proof wall. The insulation material is encapsulated between covering sheet plates. It is these plates that are jointed by means of sheet lists crossing each other right-angledly, the insulation material proper seemingly extending intactly between the plates.

GB patent specification No. 1,593,255 deals with a method for covering insulated/metal coated joints between cylindrical sections. This external clothing/insulation is covered by panels encapsulating the clothing and overlapping each other. Here, overlapping end edge portions of the panels can be fixed directly to each other without exhibiting a large force accommodating/transferring ability. Instead, around each overlapping place for the panels (which are not insulation mats, but has the task of covering a probably adhering insulation layer on the outside of the tubular or similar sections), stretchable, lockable bands have been disposed.

In accordance with the present invention there is provided a method for attaching insulation material in the form of *g.

S• units on the outside of a pipeline, each of said insulation material units being brought to extend substantially 3600 around a longitudinal portion of said pipeline and creating an intermediate join with an adjacent insulation material unit, characterized by attaching said insulation material units to the pipeline by means of fastener means in the form of an attachment band by placing the attachment band around said insulation material units and covering adjacent end portions of respective insulation units and said intermediate join; fixing said attachment band in position relative to said intermediate join; and tightening and locking said band; wherein the attachment band is a bendable, semi-rigid band having tensile strength and having fixing means for fixing the band in position.

H:\Shonal\Keep\speci\P37721 INSULATION MATERIAL 12/09/01 3a In accordance with the present invention there is further provided an attachment means for attaching adjacent insulation material units wrapped around the outside of a pipeline, characterized in that said attachment means comprises a bendable, semi-rigid attachment band having tensile strength and, in use, forms an annular shape and is adapted to be tightened 3600 around adjacent end portions of said adjacent insulation material units, said attachment band having a tensioning means co-operating with a locking means for securing said attachment band in a tensioned condition, the attachment band further having fixing means adapted to co-operate with adjacent insulation material units in order to positionally fix the attachment band on the insulation material units radially 15 of the pipeline.

In accordance with the present invention there is still further provided an attachment means for attaching adjacent insulation material units wrapped around a 20 pipeline and around a branch pipe projecting from the pipeline, the attachment means comprising a bendable, semi-rigid attachment band adapted, in use, to form an ":annular shape to attach the insulation material units at e the join area between the pipeline and branch pipe wherein a middle portion of the attachment band has a crosssection angled corresponding to an angle at the join area and the end portions of the band on either side of the middle portion are flattened such that the band extends around the join area with the end portions overlapping and fastened to secure the band around the insulation material units and wherein the band has fixing means to fix the band in position.

By means of such attachment bands which may be made relatively narrow in relation to the individual length extent of the insulation mats, the aforesaid defined problem relating to freely supported insulation units H:\Shonal\Keep\Speci\P37721 INSULATION MATERIAL 12/09/01ol 3b surrounding pipelines without any other connection with the pipeline than at the H:\Shonal\Keep\Speci\P37721 INSULATION MATERIAL 12/09/01 IWO 99/18384 PCT/N098/00300 4 joint spaces of the insulation units, is solved in a simple manner. Such bendable, tensionable, lockable attachment/ fastening bands may, without great costs, be manufactured, mounted and tightened such that they also are secured against loosening for a long time. Any deterioration of the insulation of the pipeline due to the formation of unintentional apertures between the insulation units due to the lack of holding means will, therefore, not arise.

If possibilities exist for threading in the attaching bands from one pipeline end, the attachment bands may have closed annular shape and be equipped with an appropriate tensioning device. Usually, such a threading possibility does not exist, and the attachment band is, therefore, usually made in form of a bendable band or, possibly, in the form of a divided band. Then, a tensioning device may consist of plastically deformable lips/tongues at the one free end and insertion holes in the other free end portion. The lip is inserted into and through the insertion hole and bended over such that an appropriate tensioning in the attachment band is achieved, simultaneously as locking is established through the plastic deformability of the tongues. If desired, the attachment band may be provided with a plurality of spaced insertion holes, so that the same attachment band can be used for varying pipe diameter/insulation thickness.

In order to secure an advantageous centring of each attachment band in the area of the joint spaces of the insulation mats, the attachment band or each attachment band half, respectively, may be formed with a central, inwardly projecting bead orientating itself such in said space that the attachment band easily centralises laterally. Such a bead may be 3600 continuous or formed by means of several bead portions or the like, spaced at mutually equal distances.

This centring or positional fixing, continuous bead may, possibly, be deleted if the band, at that side which come rest WO 99/18384 PCT/N098/00300 against the opposing insulation face, is provided with projections in the form of spikes. Such spikes are particularly efficient when used with insulation kept in place by means of an external net having small meshes, the spikes engaging positionally fixingly into the meshes of the net. Advantageously, the spikes may be formed through punching triangular attachment band material configurations in the form of slopingly projecting, pointed spike-like portions of the attachment band.

A non-restricting exemplary embodiment of an attachment band in accordance with the invention is further explained in the following, reference is made to the drawings, in which: Figure 1 shows a fragmentary longitudinal view through the wall of an externally insulated pipeline, the insulation mats thereof at the respective joint space being firmly connected to the pipeline by means of an attachment band; Figure 2 shows a lateral section through pipeline, insulation and a divided attachment band according to the invention; Figure 3 shows a divided attachment band fastened to a pipeline; Figure 4 corresponds to figure 3, but here the attachment band is shown from the opposite side, where one free band end carries two projecting, plastically deformable lips passed through holes in the other free band end as well as bent lockingly over, so that the tongues extend almost parallel to the band-face in the locking position; Figure 5 corresponds to figure 4, but illustrates an embodiment-comprising punched out spikes as well as a centring circular bead; WO 99/18384 PCT/N098/00300 6 Figure 6 shows a plurality of attachment bands fixed around a band where the central portion is shown in axial section; Figure 7 shows a laterally angled attachment band to be s placed at the joint place for a branch pipe; Figure 8 shows a cross-section along the line VIII -VIII in figure 7.

First, reference is made to the embodiment shown in figures 1 4. Identical components, parts and portions are indicated by the same reference numerals in figures 5 8.

Reference numeral 10 denotes a pipeline intended to be included in e.g. a ventilation plant or a pipe plant for water.

Externally, the pipe line 10 is providedwith insulation units 12 and 12', e.g. in the form of insulation mats which, is at least externally in relation to the pipeline 10, may have a foil layer 14, 14', in order to keep the insulation material proper better together. Especially in pipelines for water, it may also be used shape-durable insulation where two opposing insulation halves surround the pipe.

Joint spaces between adjacent insulation mats 12, 12' are denoted at 16.

It appears from figure 1 that an attachment band 18 according to the invention has been laid around adjacent end portions of neighbouring insulation mats, and that the end portions, thus, are clamped somewhat together in the radial direction of the pipeline 10; this being due to the tensioning of the attachment band 18.

WO 99/18384 PCT/N098/00300 7 Likewise, figure 1 shows an inwardly directed bead-shaped centring projection 20 which, upon the mounting and tightening of the attachment band 18 will seek to orientate itself within the space 16 of jointing between two neighbouring ins sulation end portions and, thus, centre the attachment band laterally. This bead-shaped centring projection 20 may consist of a circumferentially extending, continuous bead or of bead portions disposed in mutually equal distances or similar projecting means.

Figure 2 which is a cross-sectional view along the section plan line II II in figure i, shows an attachment band design consisting of two approximately 1800 semi-circular attachment band parts 18a, 18b, both having the same width and the same central bead design 20. The two attachment band halves 18a, 18b overlap each other at both adjacent end portions and are, at one overlapped end area, interconnected by means of screws 22, which exclusively have a connecting function; also see figure 3.

At the other overlapped end area, plastically deformable lips 24 on a radially seen innermost end portion 18b' of the attachment band half 18b have been passed through through-going holes 24' in the radially seen outermost end portion 18a' of the attachment band half 18a.

The longitudinal proportion is such that when the major part of the plastically deformable lips 24 on the attachment band half 18b have been pulled through said through-going holes in the attachment band half 18a, the joined attachment band halves 18a, 18b will be appropriately tightened around a standard insulation mat laid around a pipeline 10 having a given diameter, so that when the lips 24 are folded down about 900 from the piercing position an adequate tensioning is established in the attachment band 18; 18a,18b.

WO 99/18384 PCT/N098/00300 8 An absolutely necessary measure for establishing attachment band assemblies without any tendency of loosening, displacement or other weakening of the retaining function thereof, is the locking of the tightened attachment band 18; 18a, 18b.

s When using said bendable lips 24, stretching and locking are simultaneously provided for. When the lips and the adjacent portions of the end portion of the attaching band half are dimensioned adequately, the ability to deform plastically will provide a locking effect which does not let itself be nullified.

Also, the attachment band will be capable of being tightened and, thereupon, locked by means of a screw connection or in another known way.

Figures 5 8 show an embodiment characterised in band material punchings in the form of triangular spikes 26 projecting slopingly out from the attachment band face opposing the outer insulation side face. Each of these spikes 26 may have a narrow triangular circumferential shape tapering toward the free end and being connected to the remaining attachment band body at the opposite, broad end, and where each of the triangular spikes 26 normally will form a right angle with adjacent attachment band face facing the outer face of the insulation.

Sometimes in association with insulation around pipes, an external net (not shown) having small meshes and adapted to retain the insulation is used. Spikes 26 on the inner side of the attachment band are especially advantageous in connection with such fixing nets, as the spikes 26 will engage positional-fixingly into the small net meshes, so that the centring means 20, possibly, may be deleted. Attachment bands 18 having spikes 26 may also be used on the previously described insulation 12, 12' which, outermost, is provided with a foil layer 14, 14'.

WO 99/18384 PCT/N098/00300 9 In figure 6, an attachment band according to the invention is used to retain the insulation in position around a bend zone.

The composite bend may be formed on the basis of an adequately large radius of curvature or, as indicated in figure 6, through successive angulations.

The cross-section of each attachment band 18, see the attachment band extending around the joint 16A, has side faces parallel to the angled portion of the insulation 12, 12' surrounded by the band 18.

In figures 7 and 8, a specially shaped attachment band has been Shown, adapted to provide secure hold on of insulation around a branch pipe 10C emanating perpendicularly from a pipeline 10D. At its central portion, this special attachment band 18 has a right- angled cross-section, the band ends being twisted and made flat downwardly toward opposite fastening points 28, simultaneously as the attachment band portions all the time rest supportingly and retainingly against the external insulation face (mesh net face) around branch pipe and pipeline 10D in the jointing area.

Claims (10)

1. 3. An attachment means as defined in claim 2, characterized in that the fixing means is provided on a H:\Shonal\Keep\Speci\P37721 INSULATION MATERIAL 12/09/01 11 side face of the attachment band which in use faces said insulation material units, wherein the fixing means is defined by projections in the form of small spikes that attach to the insulation material units.
2. 4. An attachment means as defined in claim 3, characterized in that said insulation material units are surrounded by net means with said small spikes extending through the net means to attach to the insulation material units. An attachment means as defined in claim 4, characterized in that said small spikes are formed by o *punching the attachment band plate material to form triangular spikes.
3. 6. An attachment means as defined in any one of claims 2 to 5, characterized in that a bead-like projection is provided in a central, longitudinal eeoc 20 direction of the attachment band and is adapted to centrally position the attachment band around the adjacent insulation units by engaging with a complementary cavity o at the intermediate join between the insulation units.
4. 7. An attachment means as defined in any one of claims 2 to 6, characterized in that the band is not continuous but has at least two band members with overlapping free end portions, the tensioning means being provided at the overlapping free end portions wherein the free end portion of one band member has a projecting securing means, and the free end portion of the other member has a through-hole for receiving the securing means, the securing means being subsequently bent to lock the free end portions.
5. 8. An attachment means as defined in claim 7, characterized in that said securing means consists of at H:\Shonal\Keep\Speci\P37721 INSULATION MATERIAL 12/09/01o 12 least one plastically deformable lip, the length and positioning thereof in relation to said hole of the other attachment band member being such that a bending of the lip subsequent to its passage through said hole provides a tightening of said attachment band when the band is locked in position.
6. 9. An attachment means as defined in any one of claims 2 to 8, wherein insulation material units are placed around a pipeline band such that faces on adjacent insulation units are at an angle, characterized in that the side faces of the attachment band, in a cross- sectional view, extend parallel to corresponding angled side faces on the adjacent insulation material units. oooo
7. 10. An attachment means for attaching adjacent insulation material units wrapped around a pipeline and around a branch pipe projecting from the pipeline, the attachment means comprising a bendable, semi-rigid •co• 20 attachment band adapted, in use, to form an annular shape to attach the insulation material units at the join area between the pipeline and branch pipe wherein a middle portion of the attachment band has a cross-section angled corresponding to an angle at the join area and the end portions of the band on either side of the middle portion are flattened such that the band extends around the join area with the end portions overlapping and fastened to secure the band around the insulation material units and wherein the band has fixing means to fix the band in position.
8. 11. The attachment means as defined in claim characterized in that the fixing means is provided on a side face of the attachment band which is use faces said insulation material units, wherein the fixing means is defined by projections in the form of small spikes that attach to the insulation material units. H: \Shonal\Keep\Speci\P37721 INSULATION MATERIAL 12/09/01 13
9. 12. The attachment means as defined in claims 10 or 11, wherein the attachment band is made of two band members having the features defined in any one of claims 7 and 8.
10. 13. A method for attaching insulation material substantially as herein described with reference to and as illustrated by the accompanying drawings. S14. An attachment means substantially as herein described with reference to and as illustrated by the accompanying drawings. th Dated this 1 2 t h day of September 2001 TOR REIDAR LEA By their Patent Attorneys GRIFFITH HACK S 20 Fellows Institute of Patent and Trade Mark Attorneys of Australia *•o H:\Shonal\Keep\Speci\P37721 INSULATION MATERIAL 12/09/01