CHAIN LINK AND METHOD FOR PRODUCING A CHAIN LINK

Abstract

A chain link for a link chain has two legs running parallel to one another, and connected to one another at the ends via curves. The legs and curves are circular in cross-sections. The legs have smaller cross-sectional areas compared to the cross-sectional areas of the curves. The chain link is manufactured by radial forging with: providing a profile bar, and the profile bar is made of a steel material, inserting the profile bar into a radial forging machine and radial forging with reduction of the diameter of the profile bar in longitudinal portions, so that the profile bar is axially stretched in the forged longitudinal portion, wherein the diameter is reduced at least in the region of the later legs, and removing the radially forged chain link semi-finished product and forming the profile bar into a chain link as well as welding the front ends of the formed chain link.

Claims

1. A chain link for a link chain, wherein the chain link has two legs running parallel to one another, the two legs are connected to one another at respective ends via curves, the legs and the curves of the chain link are circular in respective cross sections, the legs have smaller cross-sectional areas compared to cross-sectional areas of the curves, the chain link is produced by radial forging, and a diameter of the legs is between 5% and 15% smaller than a diameter of the curves.

2. The chain link according to claim 1, wherein a transition region from the cross-sectional areas of the legs to the cross-sectional areas of the curves begins at the respective end of the legs.

3. The chain link according to claim 2, wherein a cross-section of the transition region has a circular longitudinal extension.

4. The chain link according to claim 1, wherein the diameter of the legs is between 9% and 11% smaller than the diameter of the curves.

5. The chain link according to claim 1, wherein, in a side view of a central longitudinal axis plane, an inner contour line and an outer contour line of the chain link have a continuous oval shape all the way around.

6. The chain link according to claim 1, wherein the radial forging takes place with axial feed.

7. A method of producing a chain link according to claim 1, comprising: providing a profile bar, wherein the profile bar is made of a steel material, inserting the profile bar into a radial forging machine and performing radial forging with reduction of a diameter of the profile bar in longitudinal portions, so that the profile bar is axially stretched in the forged longitudinal portions, wherein the diameter is reduced at least in a region of the later legs, wherein a transition region between the longitudinal portions of the later curves and legs of a chain link semi-finished product accounts for between 3% and 10% of a total length of the chain link semi-finished product, and removing the radially forged chain link semi-finished product and forming the chain link semi-finished product into a chain link as well as welding front ends of the formed chain link.

8. The method according to claim 7, wherein the diameter of the profile bar corresponds to the diameter of at least one of the curves.

9. The method according to claim 7, wherein the diameter of at least one longitudinal portion of a later leg is reduced during the radial forging.

10. The method according to claim 7, wherein the transition region between the longitudinal portions of the later curves and legs of the chain link semi-finished product accounts for between 4% and 7% of the total length of the chain link semi-finished product.

11. The method according to claim 7, wherein the welded front ends of the formed chain link are located in the region of the legs.

12. The method according to claim 7, wherein the profile bar is radially forged in a cold, warm or semi-warm state.

13. The method according to claim 7, wherein the formed and welded chain link is tempered.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Further advantages, features, and properties of the present disclosure are the subject matter of the following description. Various embodiments are shown in the figures. These simplify the understanding of the present disclosure.

[0046] In the figures:

[0047] FIG. 1 shows a part of a link chain with chain links according to an embodiment of the present disclosure in plan view,

[0048] FIG. 2 shows a chain link according to an embodiment of the present disclosure in plan view;

[0049] FIG. 3 shows a sectional view through a chain link according to an embodiment of the present disclosure according to section line A-A of FIG. 2,

[0050] FIG. 4 shows a sectional view through a chain link according to an embodiment of the present disclosure according to section line B-B of FIG. 2,

[0051] FIG. 5 shows a side view of a profile bar according to an embodiment of the present disclosure,

[0052] FIG. 6 shows a side view of a chain link semi-finished product according to an embodiment of the present disclosure,

[0053] FIG. 7 shows a side view of a radial forging machine with clamped profile bar according to an embodiment of the present disclosure,

[0054] FIG. 8 shows a sectional view of the radial forging machine according to section line C-C in FIG. 7 according to an embodiment of the present disclosure, and

[0055] FIG. 9 shows a sectional view according to an embodiment of the present disclosure of the radial forging machine.

DETAILED DESCRIPTION

[0056] In the figures, the same reference numerals are used for same or similar objects, even if a repeated description is omitted for reasons of simplicity.

[0057] FIG. 1 shows a chain link 1 according to the present disclosure in plan view, as part of a section of a link chain 2. The chain links 1 are designed here as horizontal links. The vertical links 3 connect the chain links 1, wherein the vertical links 3 are manufactured elsewhere. Not shown in more detail, further chain links 1 in the form of horizontal links, followed by a further vertical link 3 and following, are arranged on the right and left of the image plane.

[0058] FIG. 2 shows the detailed view of a chain link 1 according to the present disclosure in plan view. The chain link 1 has two legs 4, 5 that run parallel to each other and are connected at the ends by curves 6, 7. The legs 4, 5 have cross-sectional areas 8, 9, each of which is circular, see FIG. 4. The curves 6, 7 also have cross-sectional areas 10, 11, each of which is also circular, see FIG. 3. The cross-sectional areas 8, 9 of the legs 4, 5 are smaller than the cross-sectional areas 10, 11 of the curves 6, 7. At the respective end 12, 13 of the legs 4, 5, a transition region 14, 15 extends towards the curves 6, 7. The transition regions 14, 15 are also circular in shape. The transition regions 14, 15 extend from the respective end 12, 13 of the legs 4, 5 at an angle of greater than 0 degrees to an angle of less than 45 degrees, so that the legs 4, 5 then merge into the curves 6, 7.

[0059] The inner contour line 16 and the outer contour line 17 of the chain link 1 have a continuous oval shape. This oval shape of the inner and outer contour line is not interrupted at any point by a constriction, a bridge, a shoulder, a step shoulder, a slope or the like.

[0060] The diameters D4, D5 of the legs 4, 5 shown in FIG. 4 are between 4 mm and 6 mm smaller than the diameters D6, D7 of the curves 6, 7 shown in FIG. 3. Furthermore, the diameters D4, D5 of the legs 4, 5 are between 9% and 11% smaller than the diameters D6, D7 of the curves 6, 7.

[0061] FIG. 5 shows a profile bar 18 which is circular and rotationally symmetrical, with the diameter D18.

[0062] FIG. 6 shows a chain link semi-finished product 19, which was made from the radially forged profile bar 18. The chain link semi-finished product 19 has two longitudinal portions 20, the diameter D20 of which corresponds to the diameter D18 of the profile bar 18, but is also able to be smaller. The longitudinal portions 20 form the region of the later curves 6, 7 of the chain link 1. Thus, the diameter D20 of the longitudinal portions 20 corresponds to the diameter D6, D7 of the curves 6, 7.

[0063] Furthermore, the chain link semi-finished product 19 has the longitudinal portions 21 which correspond to the regions of the later legs 4, 5. Thus, the diameters D21 of the longitudinal portions 21 are equal to the diameters D4, D5 of the legs 4, 5.

[0064] A transition region 22 is arranged between the longitudinal portions 20 and 21. This corresponds approximately to the later transition regions 14, 15 of chain link 1.

[0065] The chain link semi-finished product 19 is connected at its front ends 23 to form the chain link 1.

[0066] FIG. 7 shows a simplified representation of a radial forging machine 24 in which the profile bar 18 is arranged. The profile bar 18 is clamped at both its ends via clamps 25 in the radial forging machine 24. The profile bar 18 is able to be rotated about its longitudinal axis and also moved back and forth in the axial direction via the clamps 25. Opposite punches 26 are arranged radially around the profile bar 18. This is able to be seen in FIG. 8. The punches 26 apply pressure to the profile bar 18 so that is the profile bar 18 is stretched in its axial direction. The cross-sectional area 27 of the profile bar 18 is thus reduced in the region worked by the punches 26. By axially displacing the profile bar 18 in the left and right directions relative to the image plane of FIG. 7, the entire profile bar 18 is able to be reached and forged by the punches 26.

[0067] FIG. 9 shows an embodiment of the radial forging machine 24 with 3 punches 26.

[0068] The foregoing description of some embodiments of the disclosure has been presented for purposes of illustration and description. The description is not intended to be exhaustive or to limit the disclosure to the precise form disclosed, and modifications and variations are possible in light of the above teachings. The specifically described embodiments explain the principles and practical applications to enable one ordinarily skilled in the art to utilize various embodiments and with various modifications as are suited to the particular use contemplated. Various changes, substitutions and alterations can be made hereto without departing from the spirit and scope of the disclosure.