JPH05501906A - environmental sealing - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] environmental sealing The invention applies to substrates such as cables or pipes, especially in ducts, or Regarding environmental sealing of splice cases. Such seals can be used for water, gas or other prevent contaminants from entering manholes along ducts, This can be done to protect the splice from the environment. The present invention is mainly based on sealing (this term also includes feedthrough) The present invention is useful for splice cases, pipe protection and It can also be applied to seals in other cases, including mets and the like.

May require sealing (as opposed to less thick adhesive bonding) The reason is that the substrate to be sealed and other target objects such as the housing it resides in This is because the dimensions and shapes are different between the two.

For example, a duct may be several millimeters to a few seconds larger than the cable or other substrate it contains. inches, and oval-shaped cables are present in circular ducts. The fitment dimensions of the splice case housing may may be larger than the attached cable. Also, between two or more cables If it is necessary to seal the branches of the For example, it can be enclosed by a sleeve or dimensionally recoverable (generally heat-shrinkable) sleeve. It is necessary to change the surface to a convex or straight surface.

Such sealing typically involves the use of compatible sealing members, such as O-rings. or by using a/-land, e.g. a blob of hot melt adhesive. is formed. These seals generally work well or sometimes have problems. occurs. For example, by their nature, conformable sealing members have a small modulus. creep after a long period of time, especially when used to fill large spaces. tends to occur. Also, apply enough heat to melt the hot melt adhesive. If it is not possible to do so, a leaky path may occur. For example, heat is generated during takt. It is difficult to supply.

Problems may also arise due to incompatibility or the materials required for some ducts and cables. It may happen. Cables are often made from polyethylene or lead and are They are made from PVC, steel or cement, which can be dirty or They can be brittle and difficult to clean.

Described in British patent (GB1594937, Raychem) Widely used duct seals are It consists of a hollow body member with a plurality of spaced apart flanges, each of which has a the flange extends around and away from the surface and includes a portion of the flange remote from the surface. At least a portion of the surface is deformable only at high temperatures; and/or the surfaces of the flanges have a sealant.

The European patent (EPO179657, Raychem) states that when activated, In particular, approximately 4 The book describes tact sealing for cables. Cables should be heat-sealed in duct seals. Sealed by collapsible outlet. The spring seals the part of the duct seal in which it resides. Works after heating. Heating can soften the sealing material and activate the adhesive.

The European patent (EPO152696, Raychem) includes (tact and assembly for sealing openings (such as between cables) and The assembly is a flexible tube that is adapted to wrap around itself for insertion into the opening. Envelopes (envelope-like objects), containers and containers attached to envelopes the envelope is inflated to inflate it. or accept expanding filler materials, e.g. curable foams. the container includes the inflatable material, and the means is connected to the enclosure. is adapted to introduce filler material into the envelope to inflate the envelope; an adhesive or sealant is present on at least a portion of the outer surface of the envelope; or is located in association with it. The European patent (E [PO] 52696) can be used in the present specification.

Other patent specifications disclosing hollow envelopes for sealing include: . The European patent (EPO 100228, Raychem) has at least one length A method of forming a seal between a target object and a surface surrounding the target object is disclosed; The method comprises: (a) a flexible material comprising a void-filling composition capable of changing from a low viscosity state to a high viscosity state; (b) placing the sexual envelope between the target object and the surface; (b) reducing the envelope; deforming at least a portion of the material, thereby applying the void-filling composition to the target object and surface. and (C) a step of causing the change from low viscosity to high viscosity. consists of

A European patent (EP0210807, Raychem) states that a small amount of friction between two walls A chamber filled with attrition-reducing liquids (preferably of high boiling point or low vapor pressure) or solids. Duplex in the form of a tube, using two to form a duct seal, one around the other Wall items are listed.

The article rotates on the substrate due to the misalignment between the two walls to provide environmental or electrical protection. can provide protection.

British patent (GB2006890, Kraftwerk Union (Kraftve) rk　U　n1on) has a protective tube in the wall and an isolation layer around the no. made from elastic plastic sheets and partially filled with liquid, supplied between A closure comprising a container is described. Containers are essentially Trojans. It has a toroidal shape and does not maintain a seal between the isolation layer and the tube. However, the pipe can be moved axially and radially.

US patent (US3038732, Scott and Bo nd)) includes an inflatable sealant for sealing the vibrine casing. a pipe fitting is described which conforms to the inner surface of the casing to hollow elastic means having an expanding structure in contact with the outer surface of the hollow elastic means; means for introducing the body and inflating it and centralizing the pipe within the casing; integral with and transverse to the hollow elastic means for placing and supporting; a means of relatively stiff spacers arranged at an angle, each space being A pacer means is configured to provide fluid communication within the hollow interior of the hollow elastic means. It has a passage.

The US patent (US2816575, Stokes) states that expansion An apparatus for arranging pipes is described that uses an annular sealing ring.

US patent (US3339011, Ewers Jr. et al. ) includes a long means for holding a pair of end wall panels apart. a longitudinally split sealable cylindrical case having a longitudinally split sealable cylindrical case therein adjacent to each hand end; an air-sealed cable sprocket comprising a shing and an inflatable sealing means; The rice case is marked and each end wall panel has an aligned cutout Two semi-circular disc parts with rounded outer and inner edges , thereby allowing the cable to enter the casing through the alignment cutout. and an inflatable sealing means for each of the paired panels of the end wall. an inflatable sealing means having an opening confined therebetween and aligned with the panel opening; If so trapped, the cable passing through the opening in the end wall can be expanded against bulls, the end wall is removable from the means for retaining it; The semi-circular disc portions are rotationally pinned to each other with a cutout. forming the opening in the panel whereby the semi-circular disk portion It can be pivoted open and separated for easy placement.

A bulge for insertion between the twin faces of the hub and spigot end of a pipe joint. A stretchable filling device has been awarded a British patent (GB1077314, Woodward Iron ・Listed in the company (Woodward Tron Company) ing.

Hollow wall sleeve that injects fluid to insulate ducts is now available in the UK! 'f　(GB 1421960, Commissaria a Shifuji Atomic (Commissa riat　a　Energie　Atomique)　) .

Although many of the articles described in the above-mentioned patent specifications provide a satisfactory seal, , some problems remain. For example, the use of crosslinkable or curable materials can subsequently may be inhibited or difficult to remove. Also, generally Merely pressurizing the seal with gas will reduce the lifespan of the item due to leakage or gas diffusion. It means your life will be shortened.

We can avoid these and other problems in certain aspects. Invented soil countermeasures and related articles.

Accordingly, the present invention provides for positioning a movable wall adjacent to a substrate and for communicating with the wall. the liquid holding the wall in sealing engagement with the substrate. Provided is a method for sealing a substrate that has sufficient vapor pressure to

This method does not require and generally does not involve heating. This is inconvenient It not only avoids the process steps of the It is advantageous because it allows you to The fact that solidification of the sealing material can be avoided generally This means that the seal is acceptable for migration during use and also for storage life before use. It means that life doesn't matter.

Such a method has a typical The cable accessories market is expected to have a lifespan of at least 20 years. It is particularly useful in A seal that is simply pressurized with gas will not have any obvious leaks. Even if the It's not something you should be satisfied with. Also, over many years, ducts and/or Or pressure drop may occur due to creep of cable material. deer However, according to the present invention, a constant pressure (constant temperature) is maintained despite the diffusion of pressurized steam. ). This constant pressure continues until the last drop of liquid evaporates. . If necessary, the seal can be refilled with liquid at regular intervals. Separate individual seals Even after refilling or connecting two or more seals to a common fluid reservoir. You may continue. Removal of the seal can be easily accomplished by releasing the liquid. Ru. Damage to weak cables or ducts over long periods of time must be avoided. lower pressures are preferred when a stronger seal is desired; higher pressures are preferred when a stronger seal is desired. Something bad happened.

The liquid and/or its vapor preferably or need to be in contact with the wall. The movement of the wall is not caused by the wall and some other object on which the vapor pressure directly acts. This may be done by mechanical means of interconnecting.

The movable wall preferably forms part of a flexible hollow article containing liquid. It is preferable to do so. while keeping the liquid in the reservoir away from the walls and substrate. It is also possible for the steam to communicate with the wall by means of pipes. By personal belongings This is important since it is preferable to achieve a tight seal and avoid the effects of external pipes. , now not preferred. The article contains a quantity of liquid, preferably sufficient for one filling. Can be supplied, preferably as a kit of parts, with a container containing the quantity .

The walls are preferably flexible and stretchable, so that they can accommodate substrates and substrates of various dimensions. and/or can accommodate irregularly or inconveniently shaped substrates. The wall has at least 3 two layers, e.g. a layer that acts to retain steam, mechanical strength, e.g. layers and substrate surfaces that provide tensile strength, tear strength, or fracture resistance to forms a seal against the substrate by absorbing small-scale irregularities in It has a layer that acts like this. For this purpose, the walls may contain liquids and/or bases. Metals (or hardened plastics or metal-coated plastic materials) that the body comes into contact with ), and is directly or indirectly in a face-to-face relationship with the first layer; A second reinforcing layer, such as high-density polyethylene, located between the base material and a third layer. , may consist of This third layer is made of rubber or other elastomer or foam. It may comprise a deformable material such as a foam. As this third layer, other materials, For example, using a sealing material such as a mastic or gel-like adhesive. However, for multi-purpose applications, it is preferable that it does not permanently adhere to the substrate. , the second layer has a molecular weight of 35 to 85, more preferably 40 to 80. Especially those between 45 and 75. - It is preferable that it has hardness. However, the various functions mentioned above are If it has two or more functions, it can be provided by fewer layers.

The wall may be a laminate of e.g. a metal film and a layer of plastic material on either side It may consist of Such a plastic layer allows the wall to adhere to its own heat. Can be made into hollow articles. Lap bonding, possibly using patches, preferably So formed will not delaminate under stress when the article is inflated. the Such a bond has a substantial width, for example at least 1Q mm, preferably at least 1 5) the extent to which liquid passes through the joint and thereby escapes from the envelope. decreases. Two layers of oriented, e.g. biaxially or uniaxially oriented Valeron (V Addition of high-density polyethylene, such as that known as aleror+, trademark) may be provided for mechanical strength.

Possible structures are shown below; dimensions are only preferred.

Copolymer-15-300 miflo 40-160 micron mylar (Mylar, trademark) 5- 20 micron aluminum (as single layer or multilayer) 20-80 micron Mylar (trademark’) 5-20 micron copolymer 15-30 micron This construction can be done by omitting the mylar or by using another material there. It can be changed by The copolymer must be capable of being heat bonded or welded; y) Melt adhesives, such as those based on ethylene vinyl acetate. good. Additionally or alternatively, polyamide adhesives can be used. The structure is , preferably has an elongation at break of at least 10%, preferably at least 20%. Yes. This structure can be used within the envelope, e.g. for example rubber, optionally reinforced with e.g. nylon. Can be used inside the rope. Alternatively, this could be laminated to such polymers or or may be used alone. Additional materials can reduce creep.

Typically, the sealing contact between the wall and the substrate is a line that crosses a potential leakage bath. a contact area of considerable width is preferred. be. Thus, the encapsulated article consists of a thin comb strand extending over only a portion of the first layer. It is sufficient to have a third layer of lips or ponds as described above. Base material to position a wall against or to obtain some special effect when pressurized Therefore, a first layer of larger dimensions may be desirable.

The layers described above are preferably thin in order to be flexible, but in some embodiments the layers are , may be considered the nominal layer' of an article of considerable thickness.

As explained above, the wall may form at least a portion of the flexible hollow article. preferable. This article can be wrapped around a long substrate such as a cable to vaporize a liquid. A substantially annulus that can be deformed by air pressure to increase its radial thickness. flattened (this term refers to the ability of an article to be made into a curved or similar shape, so it can be flattened) (including) a flexible envelope (openable). In this way, Dak The annular gap between the cable and the cable it contains can be sealed.

The envelope gives it rigidity or shape and/or its manufacture, e.g. Peeling to prevent opposing surfaces from sticking together during heat bonding or welding of edges between It may include sheets of material acting as layers.

Vapors or liquids may be injected into the article, but the article may be provided with a valve to prevent its release. . Instead of filling the article at regular intervals, the valve removes any remaining liquid and then Refilling is desirable, allowing for the planned release of vapor or liquid from the article. It may have means to make it.

In this way, a sufficient amount of filling can be ensured. The valve is closed when the goods are within the takt. It is preferable to be easily accessible when the item is worn, or when it is worn. Flush with the side surface, the nozzle attached to the source of liquid may be flexible Preferably, it can be accessed using a hose.

Simply tie two rectangular sheets of material together around their edges, one on top of the other. Various shapes using flat envelopes formed by joining or welding It has been found that it is possible to seal the substrate of When a hollow article with a convex surface is supplied, the article is placed inside a duct, etc. It may be desirable to sealingly engage the surface. Such hollow articles are an outwardly concave surface for sealing engagement with a cable or other substrate placed around it Alternatively or additionally, it may have. Such curved surfaces avoid wrinkles This reduces the occurrence of leakage paths and also allows the use of lower internal pressures. by thermoforming a substantially flat surface or by molding it from scratch. Can be formed by molding.

Preferably, the article is of so-called "wraparound" construction, the term Well known in the field of cable accessories, without having to access the end of the cable. This means that it has the ability to be installed around cables. (wrap around Reference may be made to the British patent (GB1155470) which discloses a sleeve. ) mentioned above In order to make the aspect of It is desirable that it extends to the side facing the.

The liquid is selected based on the specific substrate to be sealed and the environment in which the liquid will be used. . Generally, the liquid is preferably non-toxic, non-swelling, and It is preferable that it be non-corrosive to articles containing substances that are currently considered hazardous. does not have an adverse effect on any element of the environment in which it is installed. most important of liquids Its characteristic properties are its boiling point and vapor pressure over a temperature range. at atmospheric pressure The boiling point of the liquid is below 10°C, more preferably below 0°C, especially below ~5°C is preferred, but in some applications it may be, for example, up to 15°C. O The vapor pressure at 'C is at least 0.25 barg, more preferably less. at least 0.5 bar gauge, especially at least 0.7 bar gauge. Also, The vapor pressure is greater than 5 bar gauge at 25°C, more preferably at 20°C. No, especially not over 4 bar gauge, and especially not over 3 bar gauge. is preferred. Such properties can be achieved with a single liquid and its vapor, or Although it is preferred to do so, different components including liquids and gases, e.g. Mixtures can also be used. However, in the case of mixtures, it is difficult to find a suitable azeotrope. Unless one component evaporates preferentially, its composition will change over time. Sometimes. Suitable liquids include fluorocarbons, ICI trademarks, Arcton (Δ"cton), such as Arcton 134A, Arcton 114 is also possible. Arctono 134A is CH, FeF2, Arcton 114 is C) (F, CHF).

The invention will be further described with reference to the accompanying drawings.

FIG. 1 shows an envelope into which high vapor pressure liquids can be injected.

Figure 2 shows the unexpanded end face of the envelope around the cable in the duct. vinegar.

Figure 3 shows the envelope after it has expanded and contains liquid.

FIG. 4 shows a transverse section of the envelope, showing two different embodiments.

Figures 5 and 6 show alternative tube-like end faces.

The envelope in Figure 1 is generally rectangular in shape, sometimes as shown at 4. For example, by using additional pieces of particular shape between the sheets, weld them together at the edges. It comprises opposing sheet-like walls 2.3 which are attached or bonded (glued). envelope The loop may be trapezoidal as shown by the dashed line. One or more walls 2.3 and 4 are flexible and/or stretchable and are at rest, i.e. internally Before compression, the wall may be substantially flat, as shown, or may have a specific shape. That's fine. Such a shape allows for additional expansion and improves the corrugation structure. can be curved more gently to conform to the substrate to be sealed. I can sing. The wall comprises any suitable material and includes at least one metal layer. , e.g. stainless steel, aluminum or lead layer, possibly plastic A layer bonded to a backing film is preferred. Metals have very low vapor permeability In some cases, this is desirable. Also, in many applications, walls are particularly important for cables and Preferably, it does not stretch in the axial direction of the duct. Uniaxial using e.g. axial fibers Although reinforced plastics can be used in the direction, metals are again advantageous. Enbe The 9.9″ edge of the rope is attached by wrapping the envelope around the substrate. tapered to avoid creating a step in the overlapping area. It's okay to stay. Shows an envelope with a tube or pulp 5 for injecting liquid are doing. In the drawings, the tube is shown entering from the side wall. however , overlapping layers of envelopes that are joined together as a buoyancy sheet You just need to pass between. The portion of the tube that passes between the layers is wrapped It may be at least partially flattened to avoid unduly compromising the fit. wall 2 and/or 3 have a strip 6 of rubber or gel or other material. It often helps form a seal between the underlying layer containing the liquid and the substrate.

Two or more materials with different properties are placed one on top of the other or horizontally. May be used side by side. For example, insert a softer material between the harder materials on both sides. You can keep it. Envelop the foam cover with a gear knob filled with gel in between. may be supplied to the group. Material 6 is a leakage bath that can occur due to the wrinkles of the envelope. can be prevented. When attaching the envelope, the strip should be can extend through and overlap the other end. Preferred materials are ASTM D Based on 217-68 <100-350, more preferably 100-300, especially Cone penetration of 150-300 (10-'n+m) tion value) based on ASTM D638-80. an ultimate elongation of 100%, especially at least 200%, more especially at least 500% has. For further details please refer to the US patent (US4600261). I want to be. Useful materials include suitable gel precursor materials such as polyurethane, polysilane, etc. xane or styrene-elastomer block copolymers with appropriate reactivity or Kelling liquid mixtures with non-reactive extenders, e.g. mineral or vegetable oils It can be prepared by The gel may be in open cell form, e.g. in strip form. It may be included in the gaps between the materials.

In FIG. 2, the envelope l is electrically connected within the tact or splice case end 8. Wrapped around telecommunications or power cables. Preferably a cable The annular gear knob between the duct and the cable is small, for example in the center of the duct. When measured in a case, it is 10 mm or less. Larger gear knob or if present, suitable A larger envelope can be used, and a smaller envelope can be used around the cable. You can wrap the cable several times around the cable, or wrap the cable with e.g. You can change the shape of the cable. Stretch the envelope a thousand degrees around the cable, The wraps may be held in structure by tape. Next, run the envelope along the cable. by sliding the cable or by moving the cable relative to the duct. slide the envelope into the duct. Then, use the fluid dispenser or Connect the bar 10 to an envelope valve or other population, typically to gravity. The fluid 11 is injected by the self-vapor pressure within the server 10.

If the envelope has a high coefficient of friction with the cable and/or duct, or if the envelope is made of a material with a high coefficient of friction (e.g. very sticky). cable or other sealing material) on its surface. Its surface may be treated to facilitate sliding relative to the duct. For example, game The lubricant is a thin film or lubricant that may be perforated. ), having a powder or globules such as talc, having a skin, or It may be coated with these. If necessary, the gel can be subjected to pressure that causes its movement. contact between the gel and the cable and/or tact when Sea urchin coating may be selected. However, in many cases such contact is not necessary. The desired seal is achieved through the large conformability of Kel along with a thin film coating be done.

The gel may also be coated with a release layer that is removed before use.

The fluid expands or simply deforms the envelope to seal with cables and ducts. engagement thereby forming a seal therebetween. Liquid beam server-10? flows into the envelope by gravity (e.g. if the envelope is transparent) ) By observing the envelope, or by observing the change in the level of the server. By checking, enough liquid has entered the envelope as shown at 11 in Figure 3. Then, remove the reservoir 10. The rate of steam passing through the envelope material and The desired maximum length of the fill interval determines the amount of liquid required.

In some cases, the weight of the cable or the desired direction of the cable as it exits the duct within the cable or duct due to the force applied to the cable to bend it. May be eccentric. Although the present invention can absorb a considerable degree of eccentricity, If problems are likely to occur, cable support means such as hard collars should be secured within the duct. - May be placed around Burundi Island.

The fact that either pressure or fluid acts means that the pressure is uniform over the entire required surface. and its uniformity is independent of duct and/or cable creep. , and even if the cable moves off-center during the takt, It can provide considerable advantages as it can be maintained without any problems. Liquids and/or vapors must Simply move around the seal as required.

The duct seal can be removed by simply releasing the internal pressure and pulling it out of the duct. I can do it. A handle or other protruding from the duct to facilitate removal. Extensions may be provided. Such extensions are easily accessible for liquid injection. It can also function as a point.

FIG. 4 is an axial section through the duct 8 and the duct seal 1. FIG. duct sealing l is well placed within the duct, avoiding the damaged part 12. Duct sealing is at the edge 13, which does not expand but acts to properly align the seal with the duct. do. The upper and lower parts of the duct seal 1 show another aspect. lower part In this case, the seal is simply an envelope as shown in Figure 1, but in the upper part, it It comprises a plurality of preferably interconnected pockets, each expanding. Po The bracket applies pressure primarily radially, rather than axially, to cables and ducts. For force deformation to occur, the upper and lower radii of curvature as shown and It can be formed by having a smaller radius of curvature on the left and right sides. However, fig. In a surface, a larger half-curvature has the effect of reducing the effective radial component of the pressure. The diameter is left and right. If this is useful when using sealing with weak ducts There is.

FIG. 5 shows one way in which more than one cable in a duct can be handled according to the present invention. show. Here, each cable is located in a pocket within the tact seal. So Such pockets can be easily formed by the presence of cables during installation. , or preform the duct seal by molding or thermoforming a flat sort. You can leave it there. The seal includes an outwardly facing concave surface 14 for sealing against the cable and It can be seen that it has an outwardly convex surface 15 for sealing against the duct. term To clarify, surface 16 is an inward facing surface.

The convex surface extends to the outer surface of the article (in this case, convex surface 15) and connects the article to the [periphery] of the cable. It can be wrapped-around.

An alternative method to that shown in FIG. 5 is shown in FIG. Here, the envelope 1 that can be pressurized is thin and If necessary, it may have a general shape as shown in FIG. Cable 7 is Qualitatively, it is tailored into a convex shape that fills the duct 8. This is a sealing material, Preferably rubber or foam may be used, in some cases as described in US Pat. Other elas which may be of the general type described in 61, Raychem) This is done by placing the cable 7 in the hole extending through the filling piece 17 of the Tomer. I can. Reference may be made to that patent herein. Envelope 1 is pressurized the filling piece 17 is compressed around the cable and the filling piece 17 is compressed around the cable. The space between the The hole in which the cable 7 is placed is filled at 18. It may be open to the outer surface of the filling piece 17 to provide "wrap-around" properties. Granted.

An advantage of preferred embodiments of the invention is that no bonding is required between the seal and the cable or duct. It is not necessary. This not only makes removal easier, but also a safety feature I can think about it. The pressure the duct seal has is determined based on the nature of the liquid. can be done. Therefore, if the head or pond pressure is greater than the vapor pressure of the liquid, the duct If formed behind a seal, the duct seal can relieve that pressure. vice versa, Bonded duct seals are subject to dangerous pressures that can cause considerable damage when the seal eventually fails. It is possible to form a

For the avoidance of doubt, the present invention uses high vapor pressure liquids or solids and encapsulation using one or more of the other features described in the book. Provides methods and articles for and sealed articles, particularly for cables. We need to focus on what we do.

international search report international search report GB 9001283 S^　39829

Claims (32)

[Claims] 1. The process of positioning the movable wall adjacent to the substrate and placing the material in communication with the wall the liquid to hold the wall in sealing engagement with the substrate. A method of sealing a substrate with sufficient vapor pressure. 2. The method according to claim 1, wherein the liquid and/or its vapor is in contact with the wall. Law. 3. 3. A method according to claim 1 or 2, wherein the wall is flexible. 4. 4. A method according to claim 1, 2 or 3, wherein the wall is stretchable. 5. 5. According to any one of claims 1 to 4, the wall comprises at least two layers. Method described. 6. The wall includes a first layer in contact with the liquid and/or its vapor and the first layer and the substrate. 6. The method of claim 5, comprising a second layer providing a seal between the second layer and the second layer. 7. The first layer and the second layer are in face-to-face contact with each other. Method. 8. 8. The method of claim 7, wherein the second layer extends over only a portion of the first layer. 9. 9. A method according to any of claims 1 to 8, wherein the wall comprises metal. 10. The first layer comprises metal and the second layer has a Shore hardness of 35-85. 9. A method according to claim 6, 7 or 8, comprising a material. 11. The movable wall forms at least a portion of a flexible hollow article containing a liquid. The method according to any one of claims 1 to 10. 12. The article is wrapped around a long base material and deformed by the vapor pressure of the liquid to create a radius. Substantially flat flexible envelope forming an existing section that can increase the thickness in the direction 12. The method of claim 11, comprising a rope. 13. The article according to claim 11, wherein the article has a valve capable of injecting liquid. Method. 14. Claim 13, wherein the valve is substantially flush with the outer surface of the article. How to put it on. 15. Claim 14, wherein the article is substantially non-adhesive on its outer surface. How to put it on. 16. The article is externally inserted into sealing engagement with the interior surface of the duct in which the hollow article is placed. 12. The method according to claim 11, wherein the surface is convex in the direction. 17. In order for the hollow article to sealingly engage a substrate around which the article is disposed, the article at least 17. A method according to claim 11 or claim 16, wherein the method also has one outwardly concave surface. . 18. Convex or concave surfaces may be formed by shaping a substantially flat surface. , or formed by molding from the beginning, according to claim 16 or 17. How to put it on. 19. The concave surface extends to the outer surface of the article to wrap the article around the substrate. 18. The method according to claim 17, wherein: 20. Claims 1 to 19, wherein the liquid has a boiling point of 10°C or less at atmospheric pressure. The method described in any of the paragraphs. 21. 21. The method according to claim 20, wherein the boiling point is 0°C or less. 22. 22. The method of claim 21, wherein the boiling point is -25C to -5C. 23. The liquid has a vapor pressure of at least 0.25 barg at 0°C A method according to any one of claims 1 to 22. 24. The liquid has a vapor pressure of at least 0.5 barg at 10°C A method according to any one of claims 1 to 23. 25. The liquid is claimed to have a vapor pressure of 0.25 to 5 bar gauge at 25°C The method according to any one of items 1 to 24. 26. Claims 1 to 25, wherein the liquid is a mixture of two or more components. The method described in any of the paragraphs. 27. Any of claims 1 to 26, wherein the liquid comprises a fluorocarbon. Method described in Crab. 28. The substrate comprises cables or pipes within the duct; placing a hollow duct seal comprising the wall around the wall or pipe; and The vapor pressure of the liquid causes the wall to form a seal with the duct and/or cable or pipe. supplying said liquid to a duct seal so as to maintain the liquid in a state of 28. A method according to any one of ranges 1 to 27. 29. Sufficient steam to hold the movable wall and the wall in sealing engagement with the substrate An article for sealing a substrate comprising a liquid in communication with a wall under pressure. 30. Walls and/or liquid as defined in any of claims 1 to 27 30. The article according to claim 29, having a body. 31. A base material sealed by the method according to any one of claims 1 to 28. 32. Sealed in the duct by the method according to any one of claims 1 to 28. cable.