WO1999011964A1

WO1999011964A1 - Tubing piece and a method for the production thereof

Info

Publication number: WO1999011964A1
Application number: PCT/DE1998/002607
Authority: WO
Inventors: Helmut Held; Albrecht Geiger; Wolfgang Kleiner
Original assignee: Helmut Held; Albrecht Geiger; Wolfgang Kleiner
Priority date: 1997-09-04
Filing date: 1998-09-04
Publication date: 1999-03-11
Also published as: DE19881580D2; AU1021799A

Abstract

The invention relates to a tubing piece for tubing installed in buildings especially tube joint pieces or their components and heating element tubing pieces such as heating element curved connections or components of metal heating element t connections. The inventive tubing piece has a spout or a nipple for the connection of a plastic pipe or a plastic tube. According to the invention, the spout or the nipple is formed on to said tubing. In addition, the invention provides a method for producing a tubing piece during which said spout or nipple is made by means of a mechanical operation to form the end of the tube.

Description

"Pipe piece and method for producing a pipe piece"

The invention relates to a piece of tubing for building installation piping, in particular pipe connectors or their components as well as radiator pipes, such as. B. radiator connection elbow or components of radiator connection T-pieces made of metal.

Piping pieces are known in a variety of ways from building installations.

For example, the heating of single-family houses, residential complexes or commercially used buildings is generally carried out using hot water circulation systems, with the circular cut parts between the hot water pipe system (preferably made of plastic pipes) and the radiator inlet and outlet being connected regularly with radiator connection elbows or radiator T-pieces. As a rule, the heater-side end of the connection bend and connection T-piece is designed as a metallic tube and the end provided for the connection of the plastic tube as a nipple or grommet is also made of metal. So far, these connection bends and fittings have generally been made from two parts. Namely, by joining and then connecting metallic pipe and the nipple or grommet produced as a turned part. The bent pipe is inserted into the end of the nipple and then soldered together, in rare cases also welded. The nipple and grommet connections are generally manufactured very cost-intensive on lathes or CNC-controlled automatic lathes with enormous material expenditure and large material losses. A conventional manufacturing process involves the following steps:

1. Manufacture of the pipe

2. Cutting the pipe to length (for example by sawing)

3. Bending the pipe component

4. Production of nipple or grommet as a turned part

5.Pre-assembly by means of a joining step (inserting or pressing the pipe component and nipple or grommet, if necessary tacking the individual parts using welding spots)

6. Applying a solder

7. Soldering or welding the components (brazing in a protective gas atmosphere or brazing with flame technology, in rare cases also soft soldering)

8. Optical control of the solder or weld connection

9. Leak check of the solder or weld connection.

The table shown in FIG. 6 lists problems which may arise in connection with brazing in a protective gas atmosphere and brazing with flame technology. The table is divided into three main columns. The name of the problem is listed in the first column. In the following two further columns, the resulting consequences and the associated consequences are given. The Consequences column is divided into the three main categories of rework, additional costs and environmental impact.

The problem just described for radiator piping pieces also applies in a similar way to connecting pieces of other building installation piping. I.e. they are either made of several parts or if they are already in one piece, a machining process is necessary in order to produce the desired nipples or spouts from a blank.

The invention is based on the object of providing metallic piping pieces of the type described at the outset which can be produced more cost-effectively, in a resource-saving manner and with less environmental pollution.

The invention relates to a piping for building installation piping, in particular pipe connectors or their components and radiator piping, such as. B. radiator connection bend or components of Heizkδrperanschluß-T- pieces, which consists of metal and has at least one grommet or nipple for connecting a plastic tube or a plastic hose. The main idea of the invention is that the grommet or the nipple is formed. In other words, the piping is made entirely from one part. At z. B. Radiator connection elbow, a prepared pipe component is formed at one end according to the geometric configuration of the connection nipple or the grommet connection. This can e.g. B. by mechanical reshaping or by hydroforming. This also applies to components of radiator connection T-pieces, which are provided with grommets or nipples and were previously manufactured on automatic lathes or the like. The invention also relates to pipe connectors or their components which are manufactured from a previously produced malleable cast iron blank by subsequently machining it. In contrast, the mass remains unchanged in the case of a pipe connection piece or a component thereof manufactured according to the invention, since the existing material of a pipe piece, which serves as a raw part, is merely deformed.

The procedure according to the invention not only simplifies production but also reduces costs. The cost minimization results, for example, from the fact that the operations described at the outset in the production of a conventional radiator piping piece 4 to 9 are dispensed with and are replaced by a single reshaping process.

Furthermore, there is a minimization of costs and resource conservation through a significantly lower use of materials. For example, the procedure according to the invention based on the production quantities for radiator connection components published by the Federal Statistical Office in Wiesbaden for 1996 would have a material saving of approx. 2000 t of steel for a steel or stainless steel version or approx. 1000 t of copper or brass for a copper and brass version result. Additional cost savings and, above all, energy savings result from the elimination of heat-energy-intensive soldering processes. In addition, the process reliability with regard to the tightness of the parts increases, which is the most important functional feature of radiator connection components. Since the connection components are preferably installed under plaster, the smallest possible leaks at the connection point (soldering point or welding point) are caused, for example, by the finest capillary errors, with very costly water damage in the affected areas Connected buildings. Finally, environmental pollution is reduced by eliminating aggressive, acidic fluxes. This also has further cost advantages.

In order to achieve a sufficient sealing and holding force of a plastic tube pushed onto a nipple or a spout, it is also proposed that at least one preferably annular protuberance is formed on the spout or the nipple.

To increase the sealing function, it is also proposed that at least one protuberance have a plateau-like flattening on the outside. For this purpose, the tip area of the protuberance can subsequently be formed into a plateau. This measure creates particularly effective sealing points at the transition points from the flattening to the remaining protuberance with respect to a pushed-on plastic hose or plastic pipe, since the edges of the transition points have a notch effect on the plastic hose or the plastic tube. A flattening is preferably by mechanical post-deformation such. B. realized hammering, kneading, rolling or the like.

In a particularly favorable embodiment of a casing piece, at least one protuberance is sawtooth-shaped in cross section. In this way, the sharp edge of the sawtooth not only ensures a good sealing function against a pushed-on plastic tube or tube, but also prevents the plastic tube or tube from slipping off the nipple or spout

For a simple positioning of a pushed-on plastic pipe or plastic hose is also proposed that a stop collar is formed on the spout or the nipple.

In a particularly advantageous embodiment of the invention, the grommet or the nipple has a ring element in the area of the stop collar or instead of the stop collar. In this way, an overstressing of the pipe piece when forming large or several successive stop collars is to be avoided in the first place by the ring element replacing the forming collar and taking over its function. The collar function not only consists in forming a stop for a plastic tube or a plastic hose, but also to provide a support point for a tool with which, for example, a plastic hose or a plastic tube can be pulled onto the spout or the nipple. The ring element can be easily adapted to different tool types. In order to give the ring element a firm fit on the radiator piping piece, it is preferably integrated into the forming process for producing the spout in such a way that it is partially enclosed by the deformed spout geometry.

For the simple production of, for example, a radiator connection T-piece or another pipe connection piece, which consists of several components, it is finally proposed that a further protuberance is formed on a component of the radiator connection T-piece or the pipe connection piece, which is suitable for receiving a Pipe piece or another nipple or another nozzle can be opened. In this case, although a connecting step, for example, is still used for fastening the pipe piece or the nipple or the spout. B. "soldering step" is necessary, the inventive manufacture of the basic components compared to the usual manufacture as Turned part or as a casting with subsequent machining already represents a significant improvement.

As already mentioned above, the forming according to the invention can be carried out by internal high pressure forming. Such a forming process is described below by way of example.

First, the forming tool is loaded with the workpiece to be machined and sealed or sealed using presses and / or horizontal cylinders. A suitable pressure medium is then applied to the forming tool. Thereupon a counter holder for the pressure forming is retracted in a controlled manner in order to achieve the desired shape. Finally, the workpiece is relieved of pressure or relaxed, the pressure medium is removed and the forming tool is opened when the workpiece is ejected.

The shaping of the grommets or nipples can, however, also be achieved by mechanical pipe end forming. An additional aspect of the invention is thus to design the mechanical pipe end forming such that a structure in the form of nipples or grommets can be produced. In principle, the pipes to be machined are clamped in a vice with two half-shells, whereby the pipe end is exposed in the direction of the working axis. For the production of the pipe pieces according to the invention described, the forming is now carried out in several forming operations with internal mandrels, outer sleeves, flanges and combinations thereof. During the deformation process, the pipe is expanded, then drawn in or pressed axially against the vice. The tool sequences are matched to one another so that the desired final shape of the tube is achieved without exceeding the maximum stretchability of the tube. With several successive flanges or Cross-sectional changes, as in the present case for the manufacture of spouts or nipples, require further intermediate clamps against which the flanges can be pressed. Intermediate clamping can take place either by means of further clamping pieces or by reclamping the tool. In the case of fully automatic production of very large quantities, workpiece transfer after each processing stage is also possible with straight tubes, the number of clamping tools required corresponding to the number of forming tools. This measure significantly shortens cycle times.

Several embodiments of the invention are shown in the drawings, it show

1 shows a radiator connection bend according to the invention with an integrally formed nipple or grommet in a sectional view,

2 shows an enlarged section of the area delimited by the circle in FIG. 1,

3 shows a connection component according to the invention with molded nipples or grommets for a radiator connection T-piece in a sectional view,

Fig. 4 is a molded nipple according to the invention with an integrated washer and

Fig. 5 shows a T-fitting according to the invention for the building water supply.

Fig. 1 shows a radiator connection bend 1 which was produced in one piece according to the invention. The nipple 2 with the stop collar 3 was formed, for example, by mechanical reshaping. An enlarged representation of a wall section in the area of section 2 is shown in FIG Fig. 2 can be seen. For example, a plastic tube can be pushed onto the nipple 2, which is held and sealed by means of the annular protuberances 4.

3 shows a connection component according to the invention for a radiator connection T-piece. This has molded-on connecting nipples 5, 6 at both ends, which, like in the first exemplary embodiment, serve to receive a plastic hose or tube. A special feature of this connection component is, however, that a protuberance 7 is also formed. After forming, this can be opened, for example, by mechanical necking in a subsequent process step in order to be able to accommodate a piece of pipe. So far, such connection components have also been produced in one piece, but as a turned part with an enormous amount of material and labor. By means of the procedure according to the invention, this connection component can now be produced in one piece from a conventional metal tube, which is associated with a significantly lower material expenditure.

4 shows a further embodiment of a nipple 8 according to the invention at the end of a tube 9 shown in part. The nipple 8 preferably has annular protuberances 10, the rounded outer contour of which is flattened like a plateau. At the transition points 11, 12 of a plateau 13 to the originally molded protuberance, there is in each case an edge whose notch effect on a pushed-on plastic hose or a pushed-on plastic tube leads to a particularly tight connection. The plastic hose (not shown) is z. B. pulled with a tool on the nipple against a first stop collar 14. So that the tool can be supported on the radiator tube during this process, an annular disk 15 is arranged behind the stop collar 14 in addition to the stop collar 14. The washer was in the Forming process involved, whereby it is partially enclosed on both sides 16, 17 by the nipple geometry and thus has a tight fit. By using the washer 15, it is not necessary to arrange a large stop collar 14 or a plurality of stop collars arranged one behind the other to support the above-mentioned tool. This has the advantage that no undesirably high material stress occurs during the forming process, which in the extreme case can result in crack formation and thus a leak.

5 shows a T-fitting 20 according to the invention for a building water supply piping. The T-fitting 20 has two opposite nipples 21, 22 on a basic component 23. A third nipple 24 is arranged centrally in the basic component 23 between the nipples 21, 22.

The basic component 23 and the nipples 21, 22 were produced from a tubular body by a shaping step, a protuberance being provided at the point at which the third nipple 24 is located, as shown in FIG. 3. This protuberance was opened after the shaping of the basic component 23, the third nipple 24, likewise produced in a shaping step, was inserted therein and, if necessary, this joint was soldered or welded.

The nipples 21, 22, 24 have the special feature that two sawtooth-shaped protuberances 25 are formed on the nipple surface. Due to the sharp edge 26 of the sawtooth, these not only represent a slip protection for a pushed-on plastic hose or plastic tube, but also contribute significantly to sealing the hose or tube with respect to the T-fitting.

Claims

Claims:

1. Pipe for building installation piping, in particular pipe connectors or their components as well as radiator piping, such as. B. radiator connection elbow or components of radiator connection T-pieces made of metal with at least one spout or a nipple for connecting a plastic tube or plastic hose, characterized in that the spout or the nipple (2, 5, 6) is integrally formed.

2. Piping piece according to claim 1, characterized in that at least one protuberance (4) is formed to hold the plastic tube on the nipple or on the spout.

3. casing piece according to claim 2, characterized in that at least one protuberance on the outside has a plateau-like flattening.

4. casing piece according to one of the preceding claims, characterized in that at least one protuberance is sawtooth in cross section.

5. casing piece according to one of the preceding claims, characterized in that a stop collar (3) is integrally formed on the spout or the nipple.

6. casing piece according to claim 5, characterized in that in the region of the stop collar or in place of the stop collar, the spout or the nipple has a ring element.

7. casing piece according to one of the preceding claims, characterized in that a further Protuberance (7) is formed, which can be opened to accommodate a piece of pipe.

8. A method for producing a piping piece for building installation piping according to one of the preceding claims, characterized in that the spout or the nipple are produced by mechanical pipe end forming.

9. The method according to claim 8, characterized in that the tube end for forming with an inner mandrel is expanded several times and is drawn in several times with means for flanging.

10. The method according to claim 9, characterized in that several intermediate clamps are used in the flanging, which serve as counterholders.

11. The method according to any one of claims 8 to 10, characterized in that a separate forming tool is used for a high throughput for each forming step.