AU9466598A

AU9466598A - A method and a device for attaching insulation material on the outside of pipelines

Info

Publication number: AU9466598A
Application number: AU94665/98A
Authority: AU
Inventors: Tor Reidar Lea
Original assignee: Individual
Current assignee: Individual
Priority date: 1997-10-07
Filing date: 1998-10-07
Publication date: 1999-04-27
Anticipated expiration: 2018-10-07
Also published as: NO974623L; CA2307373A1; NO306003B1; NO974623D0; EP1021673A2; WO1999018384A8; IL135285A0; WO1999018384A1; AU740716B2

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 5 the form of insulation units such as mats, is placed insulat ingly 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 con 10 sisted 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 insulat 15 ing 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 20 solve the above defined problem.

WO 99/18384 PCT/N098/00300 2 Prior art as represented through patent publications, are elucidated in the following: GB patent specification No. 1,134,432 deals with an insula tion layer attached directly to the inner face of a jacket s surrounding e.g. a knee. Metal rings are used only in order to achieve a better appearance between one casing and an other. GB patent application No. 2,255,818 deals with an insulated pipeline, in which the entire insulation layer is encapsu 10 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 15 of easily releasable, mutually co-operating locking means at adjacent ends. Normally, the insulation layer around the in ner 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 to 20 gether 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 de fective and the specification lacks an explanation of the 25 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 30 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 WO 99/18384 PCT/NO98/00300 3 which, at one side, bear against a gas-tight, pressure proof wall. The insulation material is encapsulated between cover ing sheet plates. It is these plates that are jointed by means of sheet lists crossing each other right-angledly, the 5 insulation material proper seemingly extending intactly be tween 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 10 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 15 mats, but has the task of covering a probably adhering insu lation layer on the outside of the tubular or similar sec tions), stretchable, lockable bands have been disposed. In accordance with the present invention, around adjacent end portions of neighbouring insulation mats or insulation mate 20 rial in some other form, i.e. within the joint areas formed between each pair of insulation units, disposed bendable, lockable bands, especially metal bands in the form of flexi ble bands of sheet metal. Thereupon, the respective attach ment band is tensioned evenly around adjacent insulation end 25 portions at each joint space in the insulation, the tension ing also being able to cause a simultaneous locking of the respective attachment band in tensioned condition, or that the attachment bands may be subjected to a locking operation subsequently to the tensioning. 30 By means of such attachment bands which may be made rela tively narrow in relation to the individual length extent of the insulation mats, the aforesaid defined problem relating to freely supported insulation units surrounding pipelines without any other connection with the pipeline than at the WO 99/18384 PCT/NO98/00300 4 joint spaces of the insulation units, is solved in a simple manner. Such bendable, tensionable, lockable attachment/ fas tening bands may, without great costs, be manufactured, mounted and tightened such that they also are secured against 5 loosening for a long time. Any deterioration of the insula tion 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 10 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 is 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, 20 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. 25 In order to secure an advantageous centring of each attach ment band in the area of the joint spaces of the insulation mats, the attachment band or each attachment band half, re spectively, may be formed with a central, inwardly projecting bead orientating itself such in said space that the attach 30 ment 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, pos sibly, be deleted if the band, at that side which come rest WO 99/18384 PCT/NO98/00300 5 against the opposing insulation face, is provided with pro jections 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 5 positionally fixingly into the meshes of the net. Advanta geously, the spikes may be formed through punching triangular attachment band material configurations in the form of slop ingly projecting, pointed spike-like portions of the attach ment band. 10 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 15 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, insula tion and a divided attachment band according to the inven tion; 20 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 25 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 em bodiment-comprising punched out spikes as well as a centring 30 circular bead; WO 99/18384 PCT/NO98/00300 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 10 by the same reference numerals in figures 5 - 8. Reference numeral 10 denotes a pipeline intended to be in cluded in e.g. a ventilation plant or a pipe plant for water. Externally, the pipe line 10 is provided with 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 mate rial proper better together. Especially in pipelines for wa ter, it may also be used shape-durable insulation where two opposing insulation halves surround the pipe. 20 Joint spaces between adjacent insulation mats 12, 12' are de noted 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, 25 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 tighten ing of the attachment band 18 will seek to orientate itself within the space 16 of jointing between two neighbouring in 5 sulation end portions and, thus, centre the attachment band laterally. This bead-shaped centring projection 20 may con sist of a circumferentially extending, continuous bead or of bead portions disposed in mutually equal distances or similar projecting means. 10 Figure 2 which is a cross-sectional view along the section plan line II - II in figure 1, shows an attachment band de sign consisting of two approximately 1800 semi-circular at tachment band parts 18a, 18b, both having the same width and the same central bead design 20. The two attachment band 15 halves 18a, 18b overlap each other at both adjacent end por tions and are, at one overlapped end area, interconnected by means of screws 22, which exclusively have a connecting func tion; also see figure 3. At the other overlapped end area, plastically deformable lips 20 24 on a radially seen innermost end portion 18b' of the at tachment 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 25 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 30 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/NO98/00300 8 An absolutely necessary measure for establishing attachment band assemblies without any tendency of loosening, displace ment or other weakening of the retaining function thereof, is the locking of the tightened attachment band 18; 18a, 18b. 5 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 10 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 mate 15 rial 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 20 body at the opposite, broad end, and where each of the trian gular spikes 26 normally will form a right angle with adja cent attachment band face facing the outer face of the insu lation. Sometimes in association with insulation around pipes, an ex 25 ternal net (not shown) having small meshes and adapted to re tain 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 30 centring means 20, possibly, may be deleted. Attachment bands 18 having spikes 26 may also be used on the previously de scribed 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 ade quately large radius of curvature or, as indicated in figure 5 6, through successive angulations. The cross-section of each attachment band 18, see the attach ment band extending around the joint 16A, has side faces par allel to the angled portion of the insulation 12, 12' sur rounded by the band 18. 10 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 be is ing twisted and made flat downwardly toward opposite fasten ing 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 10C and pipeline 10D in the jointing area.

Claims

1. A method for attaching insulation material, preferably in the form of insulation units (12, 12'), on the outside of a pipeline (10), the insulation units each (12, 12') being 5 brought to extend substantially 3600 around a longitudinal portion of the pipeline (10), leaving an intermediate joint (16), the insulation units (12, 12') at each joint (16) being attached to the pipeline (10) through fastening means, c h a r a c t e r i z e d i n that said fastening means in 10 the form of a bendable, semi-rigid attachment band (18; 18a,18b) exhibiting tensile strength, preferably of metal, is placed around adjacent end portions of respective insulation units/insulation bodies (12, 12') and positionally fixed e.g. in relation to the intermediate joint (16), tightened and 15 locked.

2. An attachment means for use when carrying out the method as defined in claim 1, c h a r a e t e r i z e d i n that said attachment means consists of a bendable, semi-rigid at tachment band (18; 18a,18b) exhibiting tensile strength, 20 preferably of metal and which, in an annular active position, is adapted to be tightened around neighbouring 3600 annular end portions of adjacent insulation units/insulation bodies (12, 12') juxtaposed in the longitudinal direction of the pipeline,_and that the attachment band (18; 18a,18b) is as 25 signed a tension means (24) and a locking means for securing it in the tensioned condition thereof, or a combined ten sion/locking means (24), and that the attachment band (18; 18a,18b) has fixing means (20; 26; 20, 26) co-operating with the two adjacent insulation units/ insulation bodies (12, 30 12') and/or net surrounding the insulation, in order to posi tionally fix the attachment band (18; 18a,18b) laterally.

3. An attachment means as defined in claim 2, c h a r a c t e r i z e d i n that the attachment band (18; 18a,18b), WO 99/18384 PCT/N098/00300 11 centrally in the longitudinal direction, has a bead-like de sign (20) constituting said centring member and which may be 3600 coherent or broken in the longitudinal/circumferential direction of the attachment band (18; 18a,18b). 5

4. An attachment means as defined in claim 2 or 3, c h a r a c t e r i z e d i n that the attachment band is divided and has at least two free end portions (18a', 18b') having overlap possibility in the position of use, and that one (18b') of the free end portions has projection-like piercing 10 and securing means (24), and the other free end portion (18a') has a through-going hole (24') for the piercing and subsequent bending of said piercing and securing means (24).

5. An attachment means as defined in claim 4, c h a-r a c t e r i z e d i n that said piercing and securing means 15 consists of at least one plastically deformable lip (24), the length and positioning thereof in relation to the hole (24') of the other attachment band portion being such that a fold ing of the lip (24) subsequently to its piercing in the hole (24') provide a tightening and locking of the attachment band 20 (18; 18a,18b).

6. An attachment means as defined in claim 2, wherein the in sulation (12, 12') preferably is surrounded by a net having small meshes, c h a r a c t e r i z e d i n that the side face of the attachment band (18) which in use faces the insu 25 lation (12, 12'), exhibits projections in the form of spikes (26).

7. An attachment means as defined in claim 6, c h a r a c t e r i z e d i n that the spikes (26) are formed by at tachment band material punchings in the form of preferably 30 triangular spikes. WO 99/18384 PCT/NO98/00300 12

8. An attachment means as defined in any one of the preceding claims, wherein insulation units (12, 12') are placed around a bend, c h a r a c t e r i z e d i n that the attachment band (18), divided or continuous, has a cross section paral 5 lel to the adjacent insulation (12, 12').

9. An attachment means in the form of a special attachment band for use in the jointing area at a branch pipe (10C) ema nating from a pipeline (10D), the special attachment band ex hibiting an annular shape in the position of use, c h a r 10 a c t e r i z e d i n that the special attachment band (18,20,18) at two first points positioned diametrically op posed, the imaginary connecting line thereof imaginarily di viding the branch pipe in the middle of its cross section, has a substantially 90* angled cross section, and that the 15 special attachment band from these diametrically opposed points has been twisted and made flat toward the fastening point (28) of the band halves.