DE2549565A1 - Expanding or reducing dia. of tube ends - using single tool for both forming and calibrating bore and external dia. of tube end - Google Patents

Abstract

Tool consisting of a mandrel and a bush, for the accurate alteration of the dia. of a tube end for a prescribed length, by forming and calibration. The pref. tool consists of a fixing flange with a collar leading to a forming mandrel, the forming zone being bearer to the flange than the calibrating zone, which is formed by the end of a bush located on the collar by a removable peg. The forming and calibrating zones are pref. located near to each other along the axis of the tube. The mandrel and bush are automatically aligned w.r.t. each other so the time required for tube forming is reduced, prodn. being simpler and less expensive.

Description

Tool for dimensionally accurate changing of the diameter

over a certain, starting from the end face of a pipe Pipe section The invention relates to a tool for dimensionally accurate changing of the Diameter over a certain, starting from the end face of a pipe Pipe section, which essentially consists of a mandrel and a bushing for forming and calibration.

Tools for expanding or pulling in pipe sections for production of pipe connections are known. In the case of dimensionally accurate changes in diameter, in usually proceed in such a way that the pipe section excessively through the one tool is expanded or reduced and that the pipe section changed in this way then in a second, separate operation with a different tool by calibrating is brought to the prescribed target size. Through the two one after the other running operations with spatially separated tools is for the dimensionally accurate Changing of pipe sections a considerable amount of time required, whereby the end product becomes much more expensive.

The object of the invention is to reduce the time required for production to reduce such pipe sections, to simplify the production and thereby cheaper to design.

This object is achieved in that the forming and calibration required parts are combined into a single tool.

This allows the. time required to produce a pipe section with a changed, dimensionally accurate diameter can be significantly reduced, because the workflow without additional reclamping and insertion into another tool by an operator can be carried out.

Furthermore, the mandrel and the socket on the tool can be concentric and such be arranged that the calibration zone in the axial direction further from the mounting flange on the tool than the forming zone.

As a result, a successive degree of deformation is achieved. Because the diameter of the calibration zone is always larger than the outer diameter when expanding - When pulling in, however, it is always smaller than the inside diameter of the raw pipe section - When inserting the tool, it can pass over the calibration zone of the tool without changing the band to be brought. Only in the further course of the pushing-in process does the forming zone begin, in which the pipe section is either widened to an excess in the desired length - or is reduced to a smaller dimension than the nominal dimension. The calibration takes place when pulling the already formed pipe section out of the tool by the diameter is reshaped to the nominal size when passing the calibration zone. The entire change process is thus carried out by pushing in the pipe section once reached into the tool with subsequent pulling out.

Furthermore, the mandrel of the tool can have a collar which the socket is centered. Good centering affects the quality of the reformed pipe section and simplifies the assembly of the tool essential.

To use the tool also for different pipe wall thicknesses to be able to - or to be able to replace wearing parts more easily - the socket can of the tool can be connected to the collar of the mandrel by a releasable connection. By exchanging the mandrel or the bushing, the tool can easily be transferred to others Convert pipe diameter or wall thickness.

Finally, the calibration zone and the deformation zone can be axial Direction to be limited to a relatively narrow space, reducing the friction losses can be kept within narrow limits during forming.

Using an exemplary embodiment shown in the drawing the invention is to be explained in more detail. They show: FIG. 1 a tool for dimensionally accurate Expanding a pipe section and FIG. 2 shows a tool for drawing in with exact dimensions. of a pipe section.

The tool shown in FIGS. 1 and 2 consists of a tool holder 1 with a fastening flange 2 which ends in a mandrel 4 via a collar 3. A bushing 5 arranged concentrically to the mandrel 4 is pushed onto the collar 3 and connected thereto by a releasable connection 6 such as a dowel pin. When expanding a pipe section 7 (Fig. 1), the free end 8 of the mandrel 4 adapted to the pipe inner diameter 9 and expands in the direction of insertion a to Umforizone 10 with a diameter 11, which is dimensioned such that the pipe section 7 is expanded to a certain excess. Through the collar 3, the insertion depth. of the pipe section 7 are limited.

The socket 5 has a calibration zone 12 at the free end, the clear diameter 13 corresponds to the nominal diameter of the expanded pipe section. The when inserting into the tool in direction a through the deformation zone 10 on a Excessive flared pipe section is in the direction of pulling out of the tool b reduced to the nominal size (diameter 13).

When pulling in a pipe section 7, tFig. 2) is the free end 14 of the mandrel 4 is designed as a calibration zone 12 ', while the socket 5 is the Uhformzone 10 '.

In both tool designs, however, the calibration zone 12 or 12 'further away from the fastening flange 2 in the axial direction than the deformation zone 10 or 10 '.

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Claims (5)

Claims tool for dimensionally accurate changing of the diameter over a certain pipe section extending from the end face of a pipe, the is essentially composed of a mandrel and a bushing for forming and calibrating, characterized in that the parts required for forming and calibrating are added are united in a single tool. 2. Tool according to claim 1, characterized in that the mandrel (4) and the socket (5) are arranged concentrically on the tool and in such a way that the calibration zone (12 or 12 ') in the axial direction further from the mounting flange (2) is removed from the tool than the deformation zone (10 or 10 '). 3. Tool according to claim 2, characterized in that the mandrel (4) of the tool has a collar (3) which centers the socket (5). 4. Tool according to claim 3, characterized in that the socket (5) of the tool by a detachable connection (6) with the collar (3) of the mandrel (4) is connected. 5. Tool according to claim 4, characterized in that the calibration zone as well as the shape zone (tO or io ') in the axial direction (12 or 12') on one relatively narrow space is limited.