DE1047585B - Cross forging die for narrowing gradually turned and advanced pipe ends - Google Patents

Description

GERMAN

The invention relates to a cross forging die for narrowing stepwise turned and advanced pipe ends until they are possibly completely closed, as is the case with, for example occurs in the manufacture of heating manifolds.

For this purpose, it is known to combine the pipe end to be narrowed between two half dies To compress the ogival longitudinal profile and thereby give it a pointed arch shape. It is also already known to make grooves in these dies, in which the in the course of work is formed Can collect tinder.

The invention relates to a die whose half-die engravings the pipe on their when closing Capture the longitudinal edges of the adjacent zones. The longitudinal edges of the engravings are those which the Form engravings with the facing closing surfaces of the half-dies.

- According to the invention, the half-die engravings are so deep in the area of their apex or sole arched, so that the tube only protrudes from the edges adjacent to the longitudinal edges, even when the die is completely closed Zones of the engravings is applied. This means that, even when the die is completely closed, a free one Space between the apex or sole and the surface of the drawn-in pipe, d. H. on both sides of the axial plane of the pipe running in the direction of movement of the half-dies.

In this way, the pressure of the engravings is essentially only tangential to the pipe circumference the closing direction of the half-dies. The pipe wall thickens under this tangential to Tube circumference the compression pressure exerted in a restricted area in the vicinity of the engraving edges. This increases the risk of undesired deformation of the pipe and squeezing out Material reduced in the die joints. This effect extends over the entire length of the Engravings and thus the entire narrowed pipe end.

Another advantage of the engravings designed according to the invention is that the scale is not pressed into the surface of the pipe during the operation to the extent that it is otherwise and has a way of getting into the gap between the dies.

The process of compression is, as usual, associated with heating the end of the pipe to be narrowed. According to the invention, the heating device mounted inside the tube heats λν3ΐιι · εηα of the process the pipe in the of the engravings acted more strongly on the zones.

An exemplary embodiment of the invention is described below with reference to the drawing. It shows:

Cross forging die for narrowing

of incrementally rotated
and advanced pipe ends

Applicant:
Andre Huet, Paris

Representative: Dr. W. Schalk and Dipl.-Ing. P. Wirth,

Patent attorneys,
Frankfurt / M., Große Eschenheimer Str. 39

Claimed priority:
France 10 March 1954

Andre Huet, Paris,
has been named as the inventor

Fig. 1 an axial section through the half dies in the plane through their direction of movement,

Fig. 2 shows a section along the line XX in Fig. 1. As the figures show, the tube α is narrowed by being compressed between the half-joints b ¹ , b ² , which are moved towards one another in the direction of the arrows ^ and each of which is one Has cavity which has the profile of a semicircular arch in the direction of the pipe axis. The pipe end is inserted between the two half-dies and rotated between the individual closing and opening movements of the half-dies and is gradually advanced further towards the end of the engraving in proportion to its progressive narrowing or closing.

Each of the half dies b ¹ , b ² is, as shown at B ¹ and B ² in Fig. 2, hollowed out by the line PP on both sides of the axial plane running in the closing direction (arrow A) of the half dies. As a result, the metal of the tube α, as shown in Fig. 2, is compressed and upset in the tangential direction TT, T'-T ' to the tube circumference parallel to the closing direction. Instead of crushing the tube α by pressure in the area of the axial plane through the line PP , the tube is essentially compressed in the area of the longitudinal edges of the engravings, where the tube wall thickens accordingly under the pressure effect.

In this way, the narrowing can be carried out very carefully, without the risk of the material being squeezed out into the joint between the two half-dies b ¹ , b ² .

809 700/196

The process is carried out by heating the pipe zone to be narrowed. This takes place from the inside of the tube by means of a heating burner c fed via a line d. Since the line is inserted into the inside of the pipe, as shown in Fig. 1, the heating can also be continued while the half-dies are approaching. The burner nozzles are set so that the metal of the zones next to the tangents TT, T'-T ', where the compression and thickening takes place, is heated more strongly. Shortly before the end of the tube is closed, the burner c is removed and the remainder of the heating takes place from the outside.

Claims (2)

Patent claims: 1. Forging die for narrowing gradually turned and advanced pipe ends, its half-die engravings when closing the tube on the adjacent longitudinal edges Detect zones, characterized in that the half-die engravings in the area of their apex or their sole bulges so deep that the tube can only be opened by the zones of the engravings adjacent to the edge are acted upon. 2. Die according to claim 1, characterized in that the mounted inside the tube Device for heating during the work process, the tube is heated more strongly in the zones acted upon by the engravings. Considered publications:
German Patent No. 749 693;
French patent specification No. 1 045 424. 1 sheet of drawings © 809 700/196 12.58