Device and method for rolling of pipe blanks

Abstract

A device for rolling of pipe blanks has a planetary cross-rolling mill, an advancing bed, a pipe blank feed, a pipe blank advancing unit that pushes the pipe blanks through the planetary cross-rolling mill, proceeding from the advancing bed, the unit having at least one advancing apparatus, and having a mandrel rod and a mandrel rod holder. The pipe blank feed has an axial pipe blank conveying unit that conveys a pipe blank axially into a readiness position, which is provided axially behind the mandrel rod holder. The advancing apparatus is disposed between the planetary cross-rolling mill and the mandrel rod holder, and has a slide.

Claims

1. A device for rolling of pipe blanks, comprising: a planetary cross-rolling mill; an advancing bed comprising: a pipe blank advancing unit that pushes the pipe blanks from the advancing bed through the planetary cross-rolling mill, said unit having at least one advancing apparatus; a mandrel rod; and a mandrel rod holder; and a pipe blank feed; wherein the pipe blank feed has an axial pipe blank conveying unit that conveys a pipe blank axially into a readiness position, said pipe blank conveying unit being provided axially behind the mandrel rod holder, wherein the advancing apparatus is disposed between the planetary cross-rolling mill and the mandrel rod holder, and wherein the advancing apparatus has a radially displaceable pusher configured for directly pushing each pipe blank toward the planetary cross-rolling mill, wherein the pusher engages each pipe blank head-on and rams the pipe blank toward the planetary cross rolling mill.

2. The device according to claim 1, wherein the pusher comprises a rotational drive.

3. A device for rolling of pipe blanks, comprising: a planetary cross-rolling mill; an advancing bed comprising: a pipe blank advancing unit that directly pushes the pipe blanks from the advancing bed through the planetary cross-rolling mill, said unit having at least one advancing apparatus; a mandrel rod; and a mandrel rod holder; and a pipe blank feed; wherein the pipe blank feed has an axial pipe blank conveying unit that conveys a pipe blank axially into a readiness position, said pipe blank conveying unit being provided axially behind the mandrel rod holder, wherein the advancing apparatus is disposed between the planetary cross-rolling mill and the mandrel rod holder, wherein the advancing apparatus has an advancing path that is longer than half the length of the pipe blanks, wherein the advancing apparatus has a radially displaceable pusher configured for directly pushing the each pipe blank toward the planetary cross-rolling mill, mill, and wherein the pusher engages each pipe blank head-on and rams the pipe blank toward the planetary cross rolling mill.

4. A method for rolling of pipe blanks in a planetary cross-rolling mill, comprising conveying the pipe blanks to the planetary cross-rolling mill separate from one another, and rolling the pipe blanks in the planetary cross-rolling mill, wherein each pipe blank is pushed over a mandrel rod before being rolled, wherein each pipe blank is axially conveyed onto an advancing bed, wherein the pipe blanks are continuously conveyed to the planetary cross-rolling mill, end to end, wherein the pipe blanks are pushed by a radially displaceable pusher of two advancing apparatuses directly into the planetary cross rolling mill, and wherein the pusher engages each pipe blank head-on and rams the pipe blank toward the planetary cross rolling mill.

5. The method according to claim 4, wherein the two advancing apparatuses are operated with different stroke lengths from each other.

6. The method according to claim 4, wherein a front one of the two advancing apparatuses rams the pipe blank.

7. The method according to claim 4, wherein one of the advancing apparatuses passes past the pipe blank through a back stroke, while the pipe blank is being axially conveyed onto the advancing bed.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Other objects and features of the present invention will become apparent from the following detailed description considered in connection with the accompanying drawings. It is to be understood, however, that the drawings are designed as an illustration only and not as a definition of the limits of the invention.

(2) In the drawings, wherein similar reference characters denote similar elements throughout the several views:

(3) FIG. 1 shows schematically, a side view of a first exemplary embodiment of a rolling device comprising a planetary cross-rolling mill and a single advancing apparatus having a slide; and

(4) FIG. 2 shows schematically, a side view of another exemplary embodiment of a rolling device comprising a planetary cross-rolling mill and a front advancing apparatus having a slide, as well as a rear advancing apparatus, by means of which pipe blanks are alternately pushed along an axial processing segment.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

(5) Referring now in detail to the drawings, a device 1 for rolling of pipe blanks 2 shown in FIG. 1 has a planetary cross-rolling mill 3, by means of which the pipe blanks 2 are rolled, one after the other, to produce finished pipes (not numbered here).

(6) An advancing bed 4 is situated in front of the planetary cross-rolling mill 3, which bed comprises a pipe blank advancing unit 5 by means of which the pipe blanks 2 are pushed or rammed toward the planetary cross-rolling mill 3, individually and axially, along an axial processing segment 6.

(7) The pipe blank advancing unit 5 is equipped, for this purpose, in this exemplary embodiment, with a single advancing apparatus V.

(8) A pipe blank feed B having an axial pipe blank conveying unit 9 is placed in front of the advancing bed 4, proceeding axially from the planetary cross-rolling mill 3.

(9) Each pipe blank 2 is axially conveyed to the rolling device 1 particularly by means of the axial pipe blank conveying unit 9, and, in this connection, is conveyed into a readiness position 10 of the rolling device 1.

(10) The advancing bed 4 furthermore has a mandrel rod 11 and a mandrel rod holder 12 assigned to it. The readiness position 10 is situated axially behind the mandrel rod holder 12, whereby the advancing apparatus 7 is situated between the planetary cross-rolling mill 3 and the mandrel rod holder 12.

(11) Furthermore, the advancing apparatus 7 is provided with a slide 13 of a pipe blank ram 14, by means of which each individual one of the pipe blanks 2 is successively and individually pushed or rammed toward the planetary cross-rolling mill 3. In this regard, this is a discontinuous charging process.

(12) Advantageously, the slide 13 can be displaced from the axial processing segment 6, radially 15 into a waiting position 16, so that a pipe blank 2 can be moved out of the readiness position 10 into a rolling pre-position 17.

(13) In this regard, the pipe blank ram 14 can be opened in such a manner that one of the pipe blanks 2 can be pushed past the slide 13, although the advancing apparatus 7 continues to surround the mandrel rod 11.

(14) In this way, in this exemplary embodiment, a charging time of a pipe blank 2 can advantageously be reduced by at least half of conventional charging times, which can often amount to as much as 3 min in the case of pipe blank lengths of up to 21 m.

(15) The slide 13 has a pipe-like body 18 that has a radial mandrel rod introduction opening (not shown here) in the direction of its longitudinal axial expanse 19.

(16) For radial displacement of the slide 13, in this exemplary embodiment, a radial drive is provided on the advancing apparatus 7, which drive can radially displace the slide 13, accordingly.

(17) The advancing apparatus 7 is furthermore equipped with a rotational drive, not shown here, to be able to rotate the slide 13 into a corresponding displacement position for radial displacement, in which position the mandrel rod introduction opening is directed downward.

(18) In an advantageous manner, a displacement path 21 along the axial processing segment 6 can be implemented with the advancing apparatus 7, which path is longer than half the length (not numbered here) of one of the pipe blanks 2, and specifically amounts to at least the length of one of the pipe blanks 2. In this way, it is particularly possible to do without further advancing apparatuses, because the advance can be performed with this single advancing apparatus 7, which particularly brings about a very uniform drive for the pipe blanks 2, so that a correspondingly good rolling result can also be implemented.

(19) The mandrel rod 11 can remain in front of the planetary cross-rolling mill 3 because of the mandrel rod holder 12, in the corresponding inert gas atmosphere, and this particularly relieves stress on the mandrel rod 11 and also benefits the work speed.

(20) The rolling device 101 shown in FIG. 2 has essentially the same structure as the rolling device 1 from FIG. 1; however, it is supplemented with a rear advancing apparatus 130 and with a second mandrel rod holder in the form of a first holding device 131A for the mandrel rod 111.

(21) Otherwise, the rolling device 101 also has a planetary cross-rolling mill 103 that has an advancing bed 104 with a pipe blank advancing unit 105 comprising a front advancing apparatus 107 and the rear advancing apparatus 130 assigned to it.

(22) A pipe blank feed 108 having an axial pipe blank conveying unit 109 is set up proceeding from the planetary cross-rolling mill 103, axially behind the advancing bed 104.

(23) Each one of the pipe blanks 102 can be conveyed into a readiness position 110 by means of the axial pipe blank conveying unit 109, in order to subsequently be pushed along an axial processing segment 106 by means of the two advancing apparatuses 107 and 130, alternately, in the direction of the planetary cross-rolling mill 103.

(24) Likewise, the mandrel rod 111 is held in position by means of a mandrel rod holder 112 comprising the first holding device 131A and a second holding device 131B, whereby the holding devices 131A and 131B can be opened if a pipe blank 102 runs past them, because then the other of the two holding devices 131A and 131E still holds the mandrel rod 111.

(25) In this embodiment, as well, the front advancing apparatus 107 comprises a pipe blank ram 114 having a slide 113, which can be displaced radially 115 out of the axial processing segment 106 into a waiting position 116, in order to then be able to move one of the pipe blanks 102 past the slide 113 into a rolling pre-position 117. The rear advancing apparatus 130 is then activated for the last part of the pipe blank 102, which then has already run through the rolling device 101, for the most part.

(26) In this further exemplary embodiment, the pipe blanks 102 are conveyed to the advancing bed 104 by means of the axial pipe blank conveying unit 109, and are driven further in the direction of the rear advancing apparatus 130 by means of the front advancing apparatus 107, end to end. This rear advancing apparatus 130 grips the pipe blank 102 and pushes it through the planetary cross-rolling mill 103. The pipe blanks 102 are rammed into the planetary cross-rolling mill 103 by the front advancing apparatus 107, whereby if necessary, a pipe blank 102 rammed by the front advancing apparatus 107 or pushed by the rear advancing apparatus 130 can also ram a pipe blank 102 that lies behind it.

(27) In this regard, we have here a combination of pushing and ramming. In advantageous manner, a continuous charging process can be implemented in this way.

(28) The pipe blanks 102 are therefore conveyed to the planetary cross-rolling mill 103 alternately by means of the two advancing apparatuses 107 and 130, and the two advancing apparatuses 107 and 130 have different stroke lengths. The front advancing apparatus 107 has a front advancing path 121 that is longer than half the length of one of the pipe blanks 102.

(29) In contrast, the rear advancing apparatus 130 has a different rear advancing path 132. Because of the different advancing paths 121 and 132, a time available for axial conveying or axial recharging of a subsequent pipe blank 102 can advantageously be lengthened.

(30) It is understood that the exemplary embodiments explained above are merely first embodiments of the rolling device according to the invention. In this regard, the invention is not restricted to these first exemplary embodiments.

REFERENCE SYMBOL LIST

(31) 1 rolling device 2 pipe blanks 3 planetary cross-rolling mill 4 advancing bed 5 pipe blank advancing unit 6 axial processing segment 7 advancing apparatus 8 pipe blank feed 9 axial pipe blank conveying unit 10 readiness position 11 mandrel rod 12 mandrel rod holder 13 slide 14 pipe blank ram 15 radial(ly) 16 waiting position 17 rolling pre-position 18 pipe-like body 19 axial longitudinal expanse 21 advancing path 101 rolling device 102 pipe blank 103 planetary cross-rolling mill 104 advancing bed 105 pipe blank advancing unit 106 axial processing segment 107 front advancing apparatus 108 pipe blank feed 109 axial pipe blank conveying unit 110 readiness position 111 mandrel rod 112 mandrel rod holder 113 slide 114 pipe blank ram 115 radial 116 waiting position 117 rolling pre-position 121 front advancing path 130 rear advancing apparatus 131A first holding device 131B second holding device 132 rear advancement path