DE3600302A1 - Process for connecting two pipe ends - Google Patents

Abstract

In a process for connecting two pipe ends in pipelines, in particular for producing prefabricated depth charge and low-pressure lines, the pipe ends, with their end surface butting against one another, are attached together at at least three points distributed over the circumference. Thereafter, the butt joint is locked and sealed by shrinking on, under the action of heat, a plastic shrinkage sleeve pushed over the butt joint. The material for the shrinkage sleeve is expediently a cross-linkable, thermoplastic polymer with blocked curing agents and cross-linking agents, and the shrinkage sleeve is heated for shrinking such that the shrinkage-sleeve material is partly changed into its crystalline structure and cross-linked with thermosetting action. <IMAGE>

Description

The invention relates to a method for ver tie two pipe ends in pipes.

The invention particularly relates to pipe connections in prefabricated drain and low pressure lines for the Supply and disposal of buildings.

For supply and disposal lines within Buildings have changed technical requirements in particular in that the pipe installation tion is no longer in walls but in front of the wall. In addition, industrial prefabrication is increasing doing decentralized in craft businesses taken and the pipe materials required for this must be chosen and connected that the greatest possible Freedom of design within the framework of the German standard DIN 1986 becomes possible. Also the increasing installation at Alt  Building modernizations sets the possibility of a rigid Definition of the design of molded parts and their ver bond boundaries. Through the previously used connection application process, in particular welding or soldering At least the entire butt joint or sleeve connection complex and rigid and adaptable severely limited and perform because of the necessary high heating to reduce corrosion sion resistance of the pipes used, especially at the use of hot-dip galvanized or plastic layered steel pipes.

The invention has for its object a method for connecting two pipe ends in the pipe described to create lines with the help of a largely simplified prefabrication, especially one decentralized prefabrication is made possible and at the same time a particularly simple procedure is created, the preparation and final creation of the Connection made much easier and in particular the final establishment of the connection at the construction site promotes. The procedure should be for as many pipes as possible line materials can be used and a high corrosion maintain sion resistance at the connection point, but at the same time a secure mechanical and tight connection guarantee. It is therefore particularly useful for the Installation in front of the wall and for the modernization of old buildings strived for a particularly favorable process.

This is achieved according to the invention in that proceed as follows: The pipe ends are with their faces abutting on at least three stuck together around the circumference, and afterwards it becomes the point of impact by heat Shrink on one pushed over the joint  Locked plastic shrink sleeve and sealing ver seals. In particular media-carrying stainless steel pipes, Koh Steel tubes with hot-dip galvanizing and weldable and bondable plastic and in particular polymer pipes can thus be manufactured without sleeves, and then it can According to the invention, the pipe connection in the described Way to be made. On the complete connection the end faces of the abutting pipe ends with the associated effort and with metal pipes and weaknesses associated with a welding process corrosion resistance can be dispensed with entirely. The pipe ends to be connected are only punctiform tacked together so that a rigid pre-connection is achieved between the pipe ends, which is thus a first Strength for handling and also transport and the storage entails. The shrink sleeve, e.g. a shrink sleeve or a shrink tube, can beforehand in a standby area next to the pipe joint be pushed. The connection point prepared in this way will in the workshop or after adjustment work on the construction thereby complete that the shrink sleeve through a soft blowtorch or a hot air gun, at least by the action of heat, warmed and thereby to Shrinkage is brought. Handling the connection and exposure to heat are completely problem-free and can the construction site can be easily carried out. The one on it Lock and Ver manufactured according to the invention Sealing of the pipe connection area is characterized by high mechanical resistance (tests have a mecha nical resistance up to about 5 bar), a high thermal resistance to continuous load of 100 ° C and by a torsional strength, which by three-point stitching is achieved. Despite the safe Prefabrication according to the drawing remains in the workshop  in this procedure according to the invention the bausei correction possibility in the event that either briefly change requests occur in due time or when through breaks in ceilings and walls for structural reasons Workarounds have to be made that only at the e.g. Modernization work become visible. The invent The procedure according to the invention also opens up small loading pursued the opportunity to prefabricate workshops engineering planning, so not on industrial prefabrication to be instructed like this e.g. with steel drain pipes and also largely with poly ethylene drain pipes is the case that is not out of trade usual pipes and fittings are assembled. The method according to the invention is suitable for connection all pipes and fittings used in installation technology Pipe fittings and pipe fittings in the specified different materials.

Especially for stainless steel and hot-dip galvanized pipes In principle, carbon steel already results described advantage that circular seams are dispensed with can, without impairing the functionality, and that by the three-point stitching according to the invention sufficient mechanical strength for storage, transport and installation is given. It also becomes harmful Impairment of the corrosion resistance by the small issue size avoided. The conventional rigidity All-steel welded constructions practically continue used, the disadvantage of the insolubility of such pipe Connections avoided, however, because of the effort for the Elimination of a welding spot on e.g. Stainless steel or corrosion-protected galvanized steel pipe is low. The shrink sleeve can ent by heating in an emergency be removed.  

If the pipe ends to be connected are made of metal, see above the end faces of the pipe ends can be welded, especially spot welding, or soldered together will. For all materials and especially for pipes The end faces of the pipe ends can be made of plastics but also at the peripheral points by gluing to each other to be stapled.

A particularly useful embodiment of the Er Invention arises when as a material for shrinkage sleeve with a cross-linkable thermoplastic blocked hardener and used with crosslinking agents and the shrink sleeve to shrink it like this is warmed that the shrink sleeve material partially crystalline formed and duromer crosslinked. Thereby the entire pipe connection is particularly secure on the Pipe joint glued low pressure resistant and in the pipe joint area sealed especially tight. The shrinking can in simply by a soft blowtorch or by a hot air dryer can be used. The shrink sleeve can be provided with an adhesive layer on the inside liability and sealing are further improved and the respective pipe materials and pipe shapes can be fitted.

Has proven to be particularly useful as a shrink sleeve heat shrinkable tube made of modified cross-linkable Proven polyolefin. The polyolefin tube with an inner coating from a plastic protection be provided.

Further features, advantages and details of the invention result from the following description Embodiment of the invention with reference to the drawing, the process steps using the example of pipe connections demonstrated. The drawing shows:

Fig. 1 is a partially sectioned side view of the Ver connection of two pipe ends prior to the shrinking of the shrink sleeve,

Fig. 2 shows the pipe connection of Fig. 1 after shrinking the shrink sleeve and

Fig. 3 is a partially sectioned side view of a pipe area with pipe fittings and three pipe connections, made by the method according to the invention.

The method according to the invention will be explained in principle with reference to FIGS. 1 and 2: the pipe ends 1 and 2 are to be connected. They are smooth pipe ends, e.g. made of stainless steel or hot-dip galvanized carbon steel or plastic-coated steel or also made of plastic.

As the clarification because of exaggerated spacing of the pipe ends and largely shown schematically, the pipe ends 1 and 2 with their end faces 1 a and 2 a are butted against one another on three circumferential locations 3 distributed around the circumference, in the case of pipe ends made of metal and in particular made of steel at spot 3 welded. In the drawing, the distance between the end faces 1 a and 2 a and the stitching or welding points 3 are exaggerated Darge.

After this process step, the pipe ends 1 and 2 are thus rigidly connected to one another. Appropriately, especially for pipe fittings, a shrink sleeve 4 made of a crosslinkable thermoplastic with blocked hardener and with crosslinking agents has been pushed onto one of the tube ends, here the tube end 2 , before the described stitching process. In Fig. 1 this shrink sleeve 4 is shown in the initially pushed-on state with dash-dotted lines.

Is the stapling process finished, the shrink sleeve 4 is pushed over the joint, as shown in Fig. 1 in solid lines. Then the joint is locked by heat-shrinking the shrink sleeve 4 pushed over the joint and sealed ver sealed. This final state is shown in FIG. 2. The dimensions of the shrink sleeve and its material and, if appropriate, an adhesive layer provided on the inside are selected depending on the application, for which material information is given at the beginning. The heat input for shrinking the shrink sleeve 4 can be done with a soft blowtorch or with a hot air gun. The heat input is appropriately carried out so that the material of the shrink sleeve 4 is partially crystalline and duromer crosslinked. Fig. 3 shows for explanation again on a pipe line area three connections that are made by the method according to the invention. The pipe ends 5 and 6 on the one hand, 7 and 8 on the other hand and 9 and 10 on the third are to be connected to each other. The connection or joint I shows the connection after attaching the end faces of the tube ends 5 and 6 as shown in FIG. 1 and with the shrink sleeve 4 pushed sideways in a reserve area before they shrink.

At the connection point II, the shrink sleeve 4 is pushed over the joint between the pipe ends 7 and 8 . The tube ends 7 and 8 are also tacked together at three circumferential locations, as shown schematically in each case at 3 . The shrink sleeve 4 has not yet shrunk.

At the connection point designated III, the connection method according to the invention is completed for connecting the pipe ends 9 and 10 . The shrink sleeve 4 is shrunk over the tacked joint between the pipe ends 9 and 10 by heat input.

Claims (8)

1. A method for connecting two pipe ends in Rohrleitun gene, characterized in that the pipe ends are butted against each other with their end faces on at least three circumferential locations distributed on the circumference and that the joint is then locked by heat-shrinking a shrink sleeve pushed over the joint made of plastic and is sealed sealed. 2. The method according to claim 1 for two pipe ends made of metal, characterized in that the end faces of the tube end by welding, especially spot welding, or soldered together. 3. The method according to claim 1, characterized in that the end faces of the pipe ends by gluing them together to be stapled. 4. The method according to any one of claims 1 to 3, characterized ge indicates that as a material for the shrink sleeve  a crosslinkable thermoplastic with blocked hardener and used with crosslinking agents and the shrink sleeve for shrinking in such a way is heated that the shrink sleeve material partially crystalline formed and duromer crosslinked. 5. The method according to any one of claims 1 to 4, characterized characterized in that the shrink sleeve inside with a Adhesive layer is provided. 6. The method according to any one of claims 1 to 5, characterized characterized in that a heat shrink as a shrink sleeve fender tube made of modified cross-linkable poly olefin is used. 7. The method according to claim 6, characterized in that that the polyolefin tube with an inner coating is provided from a plastic protective compound. 8. Connection of two pipe ends, characterized by their Construction by manufacture according to one or more of the Claims 1 to 7.