US3366767A

US3366767A - Production of seamed metal tubes

Info

Publication number: US3366767A
Application number: US385164A
Authority: US
Inventors: Corta Hubert De
Original assignee: Lorraine Escaut SA
Current assignee: Lorraine Escaut SA
Priority date: 1963-07-29
Filing date: 1964-07-27
Publication date: 1968-01-30
Anticipated expiration: 1985-01-30
Also published as: GB1039409A; DE1452360B2; AT262731B; FR1377333A; ES302534A1; CH424692A; NL140441B; DE1452360A1; NL6408608A; BE650814A

Description

Jan.30,1968 H.DE CQRTA 6,366,767

PRODUCTION OF SEAMED METAL TUBES Filed July 27', 1964 I 4 Sheets-Sheet 1 FIG. 2a

Flt 3.1a-

INVENTOR HUBERT 0s CORTA BYW /W ATTORNEYS Filed July: 27, 1964 PRODUCTION OF SEAMED METAL TUBES 4 Sheets-Sheet 2 l NvE-N TOR HUBE RT DE CORTA ATTORNEY S Jan. 30, 1968 H.DE CORTA PRODUCTION OF SEAMED METAL TUBES 4 Sheets-Sheet 5 Filed July 27, 1964 INVENTOR HUBERT DECORTA ATTORNEYS H. DE CORTA O I 3,366,767

Jan. 30, 1968 PRODUCTION OF SEAMED METAL TUBES 4- Sheets-Sheet 4 F led July 27, 1964 MHNHC mm mm 60 Y INVENTOR HUBE RT DE CORTA BY/ V 0 ATTORNEYS Uite rates ate" 3,366,767 PRGDUCTION F SEAMEI) METAL TUBES Hubert de Corta, Fontenay-Sous-Bois, Seine, France,

assignor to Lorraine-Escaut, Paris, France, a company of France Filed July 27, 1964, Ser. No. 385,164 Claims priority, application France, July 29, 1363, 9 032 4 Claims. 61. 219-8.5)

ABSTRACT 6F THE DISCLOSURE Installations already exist in which seamed metal tubes are made from flat material. Such installations are, generally speaking, laid out in the form of a straight production line, a band of sheet metal being introduced at one end of it and a succession of seamed tubes emerging at the other. From one end of the line to the other, these installations may comprise a shaping device, in which the unwinding band of metal is first shaped to form an open tube, a Welding position, where the open tube is welded, the edges of the metal being brought together, and a gauging mill in which the tube, which may first have been heated, is reduced to its correct size, after which it can be divided into whatever lengths are desired.

Such installations, already known to technologists, op erate satisfactorily and can commonly run at speeds in the neighbourhood of 180 feet a minute.

Various ways of increasing the amount of seamed tubes produced may be considered. One can try to raise the speed at which the tubes pass through the installation, but the technical limits of such an improvement are very soon reached. Another possible approachand this is what is aimed in the present invention-is to attempt to design a plant capable of turning out several parallel runs of tubing simultaneously.

In more precise terms, the invention relates to an installation for the continuous production of seamed metal tubes, having as its distinguishing feature the fact that, from a single band of metal, it can cut, shape, Weld, reduce to size and finaly divide off several runs of tubing travelling along separate parallel paths. From the point where the single band of metal is fed in, this installation comprises, in its essentials, a cutting position, where the metal is cut into parallel horizontal strips; a positioning unit, in which these strips are suitably spaced apart and where certain of them may be turned over so that the cutting burrs on all the strips may turn the same way; a multiple former, the paths through which are spaced in the same way as the strips, the shaping being independently regulated for each path; a multiple welding unit; a unit for cleaning up the weld from the outside of the various tubes; possibly a multi-path gauging unit; and, iinally, a shearing unit.

Such an installation, made up of units each having 11 paths, naturally takes up less space from side to side than would the combination of n single-path monotube units, by virtue of the judicious positioning of the various members for the various paths.

The purpose of turning over certain of the strips cut from the original single band is to ensure that all the cut- 3,366,767 Patented Jan. 30, 1968 ice ting burrs resulting from cutting the band into strips are, for example, turned upwards. In this way, during the shaping of the various runs of tubing, in the course of which the side edges of the different strips are curved inwards and upwards, the cutting burrs thus come to lie on the inside of the various tubes that are being formed simultaneously.

The welding of the tubes may be carried out by any known method, such as induction or contact welding. It is also possible to incorporate in the installation whatever tube cooling or heating arrangements are required for applying any particular method of welding and of finishing the tubes after welding.

The description that follows, in conjunction with the accompanying drawings, which are primarily intended to serve as examples, will explain clearly how the invention can be put into effect. Here it should be stated that the invention is essentially concerned with the production of an odd number of tubes from a single original length of sheet metal. In view of the possible technical complications arising from a large number of tubes, preference has been given to the simultaneous production of three runs. Reference will be made to the accompanying drawings, in which:

FIGURES 1a, 1b and 1c are diagrammatic plan views of the feed, intermediate and delivery sections of the installation, respectively; and

FIGURES 2a, 2b and 2c are side elevations correspond ing respectively to FIGURES 1a, 1b and 10.

At the feed end of the plant, a band 1 of sheet metal running horizontally, is continuously fed forward and suitably presented to the equipment by guide members 2. The band 1 passes through a cutting unit 3, in which shears 3a divide it into three strips, B1, B2 and B3, of which B1 and B3 lie outside the strip B2, one on either side. Any burrs that are inevitably formed in course of shearing are turned upwards (standing out from the upper face) on the strip B2 and downwards (standing out from the underside) on the strips B1 and B3. Since, as will be seen later, the shaping of all the strips is done by curving their edges inwards and upwards, it is desirable that the cutting burrs on all the strips should be turned upwards, so that they may come on the inside of the tubes when these are formed. This means that both strips Bland B3 must be turned over before going to the forming unit. In addition to this, all three strips B1, B2 and B3 need to be suitably spaced apart in parallel lines before going to the forming unit.

For turning over the strips B1 and B3 and for obtaining the proper relative spacing between the strips B1, B2 and B3, a turning and positioning unit 4 is employed. This consists essentially of two guide rollers, 4a and 4b, mounted on vertical spindles. Strip B1, which makes contact in a vertical plane with the guide roller 4a, thus passes into the vertical as it comes level with this guide roller, beyond which it continues turning over until its. two faces have been transposed. The same happens to the strip B3, which, after making contact in a vertical plane with the guide roller 4b, finally has its two faces transposed. After passage through the unit 4, not only do the three strips B1, B2 and B3 carry their cutting burrs on their upper faces, but they are also all spaced at the same relative distance e apart.

The strips B1, B2 and B3 are now ready to enter the forming unit 5, travelling in three separate parallel paths centered on the lines A1, A2 and A3 respectively (FIG. lb).

A forming (or rolling) unit 5 is providedwhich, as with the other units in the production line, will not be described in detail here-differs from monotube units of this kind only in being designed to form three tubes at a time, all its shaping and guiding members being provided in triplicate and judiciously laid out so as to keep the transverse dimension as small as possible and well below three times the corresponding dimension of a monotuoe forming unit. The unit comprises a receiving guide system 6 (FIG. 2b) and a certain number of vertical cages such as that numbered 7, in which the strips B1, B2 and B3 pass between forming rollers, which apply substantially vertical shaping pressure, and horizontal cages such as that numbered 8, in which the strips B1, B2 and B3 pass between forming rollers that apply substantially horizontal shaping pressure. The strips are thereby formed into tube blanks T1, T2 and T3. It should be noted that for the horizontal cage 8, for example, the pair of rollers 62, which is shaping the middle tube blank T2, and the pairs of rollers G1 and G3, which serve to shape blanks T1 and T3, are longitudinally offset in a staggered relationship, to reduce the side-to-side width of the unit.

Similarly, the terminal pairs of forming rollers, F1, F2 and F3, at the delivery end of the forming unit, corresponding respectively to blanks T1, T2 and T3, have their axes oifset in a staggered relationship along spaced parallel lines, such an arrangement also making it possible for the final shaping pass on each of the three tubes to be independently regulated.

On leaving forming unit 5, the tubes are guided independently by guides 9a and enter a welding unit 9, where they are welded at points s1, s2 and s3 respectively, these points being staggered longitudinally, with the aid of weld rollers S1, S2 and S3. The welding may be carried out by the radio-frequency method, for example, by induction or by contact, power being supplied through a transformer 10.

Upon leaving the welding unit, the tubes go to a trimming unit, where

trimmers

11, 12 and 13 finish off the weld on the outside of the tubes. These trimmers are characteristically staggered longitudinally.

The formed tubes T1, T2 and T3 next pass in FIGS. and 2c into a cooling unit, 14 (consisting of sprinkler arrays, for example), and then to a gauging unit comprising a certain number of vertical housings such as that numbered 15, horizontal housings such as that numbered 16 and Turks head straightening units such as that numbered17. The rollers of the horizontal housing 16 and some of the rollers of the straightening units 17 are longitudinally oifset in a staggered relationship. Finally, the three runs of tubing T1, T2 and T3 pass to a dividing head 13, where they are cut by shearing means into lengths as required.

It will be noted that the description of the various component units of the installation has not covered such details as the mechanical drive of each unit. Such details are readily available to those skilled in the art and do not form part of the invention as such, which is primarily concerned with the combination of a mechanism H for shearing the initial single band of metal with the subsequent turning and positioning of strips B1, B2 and B3 and the judicious laying out of the various parts of the plant so as to reduce the overall space occupied to the minimum.

A further point to note is that the installation conforming to the invention makes possible either the simultaneous production of tubes which are preferably of the same diameter or the simultaneous production of tubes of diflierent diameters.

What is claimed is:

1. An installation for the continuous production of a plurality of Welded metal tubes from a single metal band, said installation comprising in combination and in the stated order;

(a) feeding means for feeding a single metal band to a cutting location,

(b) cutting means at said cutting location operable to cut said single metal band into a plurality of metal strips,

(c) positioning means operable to locate each of said plurality of metal strips in a spaced parallel relationship and to turn over alternate strips so that burrs formed by said cutting means face in the same direction for all of said plurality of metal strips,

(d) separate forming means associated with each strip independently, with rollers to form a tube blank from one said plurality of metal strips associated with said separate forming means, at least some of said separate forming means with rollers, offset from each other in a staggered relationship along spaced parallel lines,

(e) separate welding means offset from each other in a staggered relationship along spaced parallel lines associated with each of said tube blanks independently to weld said tube blanks,

(f) separate cleaning means offset from each other in a staggered relationship along spaced parallel lines, associated with each of said welded tubes independently to clean the weld of the associated tube, and

(g) shearing means operable to cut each of said associated tubes in predetermined lengths.

2. The installation of claim 1 wherein said separate welding means is a radio frequency welding means jointly controlled.

3. The installation of claim 1 wherein said cutting means is operable to cut said single metal band into three metal strips.

4. The installation of claim 1 including separate gauging means associated with each of said cleaned welded tubes independently with rollers, at least some of said separate gauging means with rollers offset from each other in a staggered relationship along spaced parallel lines, said separate gauging means disposed between said separate cleaning means and said shearing means.

References (Iited UNITED STATES PATENTS 759,480 5/1904 Shifley 72-129 2,631,361 3/1953 Wallace 29477.7 3,230,336 1/1966 Gueugnier 2l9-8.5

RICHARD M. WOOD, Primary Examiner.

l. G. SMITH, Assistant Examiner.