DE1602249A1 - Method and device for drawing deeply grooved pipes - Google Patents

Description

The invention relates to methods and devices for pulling deeply corrugated or fluted pipes.

So far attempts have been made to form corrugated tubes in the longitudinal direction by using cylindrical tubes be pulled through a structure capable of creating grooves of the desired depth, in general unsatisfactory results. In these experiments it was shown that there is a risk that the Pipe collapses or splits in an unpredictable manner, so that the pipe breaks during the initial deformation.

According to the invention, pipe material is drawn and provided with longitudinal grooves or corrugations at the same time, namely on such a Vifeise that grooves of relatively great depth or height can be produced, it being possible at the same time, both the inside diameter and the outside diameter of the pipe at all points along the pipe circumference and the wall thickness

009832/052 8

to regulate exactly. Generally speaking, this is made possible through the use of a compound pulling tool, the a first section which is shaped to create relatively shallow grooves in the tubing which face one another the original cylindrical shape of the pipe radially extend inside, as well as a second or downstream grooved portion which has a conical groove and with Grooves is provided, which are dimensioned so that the pipe material receives the desired external dimension. With these sections of the drawing tool, a composite mandrel works together.

One object of the invention is thus to provide methods and devices which are characterized in that that the grooves are produced in two working steps; here the initial creation of the grooves is from a flood sink of the material accompanied to a significantly reduced inner and outer diameter, while at the same time the depth of the Grooves is enlarged to the desired dimension.

The invention is explained in more detail below with reference to schematic drawings of an exemplary embodiment

]? ig. 1 shows in perspective a pipe section and leaves recognize the stages that go through in making it will.

Figure 2 is an enlarged cross-section through a finished longitudinally grooved tube.

Mg. 3 is a longitudinal section through the compound

Drawing tool and mandrel assembly along line 3-3 in i'ig. 4th

0 0 9832/0528

Pig. 4 is a cross section taken along broken line 4-4 in FIG. 3.

In Ji ¹ Ig. 1 shows a perspective side view of a part of a pipe T. In Pig. 1 it is assumed that the drawing process was interrupted when the tubing was in the drawing tool "and that the partially formed and drawn tube has been withdrawn from the drawing tool. It can be seen that the tube T has a smooth cylindrical section at its left end 10, while it is provided with deep grooves 14 and also has a considerably reduced diameter at its extreme right-hand end at 12. Between the sections 10 and 12, the pipe, which is partially provided with the longitudinal grooves, forms a conical section within a zone 16. In particular notes that in a further zone 17 the grooves are initially created in a cylindrical portion of the tube by displacing material radially inwardly to produce inwardly projecting, partially formed corrugations without the greatest diameter of the pipe is significantly reduced in size.

To give an example of a tube in the manufacture of which the invention has proven particularly advantageous reference is now made to FIG. 2; Pig. 2 shows the dimensions of a particular longitudinally grooved pipe having grooves or grooves 20 each between adjacent to them, outwardly projecting ribs 22 lie; the hats define inwardly projecting ribs 24; the

0098 32/0528

Between the apexes of the ribs 22 protruding outwards, the tube has a largest diameter of about j> 8 mm, between the apices of the inwardly protruding ribs -24 a smallest inner diameter of about 29 * 2 mm, with between the apexes of the outwardly protruding Ribs and the apices of the inwardly protruding ribs results in a depth of the hats of about 4 »45 mm, as well as a wall thickness of about 0.8 mm. This grooved or grooved tube can be manufactured according to the invention from a tube material which is composed of 70 $ of copper and 30; i of Mekel, the outer diameter being about 62.5 mm and the wall thickness about 0.8 mm. In the special example dealt with here, 16 grooves or envelopes are provided, but it should be noted that the number of butene can be changed as required.

In FIG. 3, a composite drawing tool, designated as a whole with mi c -JQ, is shown, which is mounted in a / tool block of known construction; the drawing tool 30 is assigned a composite mandrel 32 which is supported in the opening of the drawing tool by suitable support means, for example a mandrel support rod 34.

The first stage of the composite drawing tool comprises a ring 36 with a plurality of radial cylindrical openings 38, the number of which corresponds to the number of uutes with which the pipe is to be provided. Each of the cylindrical openings 38 takes a short piece 40 of cylindrical material, e.g. a boring bar material? the ends of the rods 40 pointing radially inward are "in-i" -ig. 4 denoted by 42.

0 09 8 32/052 8 BAD ORIGINAL

1802249

The rods are precisely adjusted. · So that: _ they protrude inwards to the required extent, and; they will be in the. right La ^ e else to appropriate v /, eg by clamping screws 44>-i-'eöiijSlegt. On the- in the. The side of the xting 36 pointing towards the drawing direction is formed with a collar 46 serving to determine the position. whose mode of action will be discussed in more detail below. ■

The hung. 36 is enclosed by a retaining or support ring 48, the "" openings 50 for receiving connecting screws 52 '. Under the heads of the locking screws 52 are disks 56, which overlap the ring 36 with their radially more inwardly located elements, and which serve to to hold the Hing in the correct ϊ / inclination to get the correct flux between those formed by the rods 40 Surfaces for shaping the floods, and the corresponding surfaces' to ensure which in the-second section of the: compound Drawing tool are provided *

The second section of the compound pulling tool> which is designated in Fig. 3 with 58, has G-threaded bores to take out the connecting screws 5-2 .Front side is the section 58 at 62 with a recess provided for receiving the federal government 46, so that the v / Erkzeugabacünitue 36 and 58 are held in their symmetrical position.

lii.Q. bpi 64 represents ^ ejjteilt, the inner surface of the t / ernzeugau3-crmii: t3 "36" zylindriücix "; .. and the JDraeu ^ ung .der fluten is bjt αΐν-θίπ iLij: jr; hnibt Juroh the radially inwardly protruding! ■, nden -if-r JLui; -; un 40 causes, the second (/ Erk «3iigab: iohnitb 58

^V> _{0O 9832} VO _{528 BAD0RraiNAL}

is stranded at -56 with a tapered confluence, and the part of this section of the Seeing tool has relatively deep grooves, and it comprises a letate-n section 67 of FIG essentially constant cross-section.

The total of 32 designated be composite mandrel comprises a hats final shaping section 68 of generally constant, deeply grooved cross-sectional shape, which paiät in the grooved section 67 of the Y / tool part 58 paiät. This mandrel section extends from a connecting piece 70 which is provided with a G-thread bore and into which the mandrel support rod 34 is screwed. A section 76 for the preparatory shaping of the grooves is arranged on the mandrel. This section can be made of any suitable material, but it will be understood that excellent results will be obtained when this section is made of nylon. The initially coming into effect, serving to form the grooves mandrel portion 76 includes a collar or ring 78 and may be of, the final shape of the grooves loading _/ voting mandrel portion 68 or} supporting the connecting piece 70 of the collar or ring 78 against an annular shoulder 79 in the correct angular position .be held in a suitable manner, for example by means of a clamping screw 80.

If the device described above is to be used, one end of the one relatively large amount of time will be required exhibiting- Ruhrinateriala auer.rt sharpened, in the together - abe Pulling tool introduced and then with a device

connected to pull the pipe through the tool, .Tenn that

009832/052 8 ^ -

Pipe material initially in contact with the rounded Ends 42 of the dtangen 40 comes - it is introduced with hats of considerable depth, without, however, the outside- diameter of the pipe material is significantly reduced. Then comes the raw material with the partially formed liuteh to the plant at the tapering mouth of the ', / tool section 58, and now the pipe material is drawn in approximately to the desired inner and outer diameter, and at the same time, the bottom come into contact with the grooved Parts 67 of the drawing tool and the grooved parts 68 of the Horns. It can be seen that with the arrangement described, the instantaneous external and internal dimensions of the pipe material during the generation of the loud and the pulling in of the pipe— materials are always precisely determined, and that therefore a constant regulation of the .Vand thickness is maintained accordingly will.

The 'invention is of course' particularly applicable when pipes provided with deep grooves of relatively small ', / and thickness of Z..B. about 0.50 to about 1.25 mm are to be produced. According to the invention, the successive drawing steps are carried out on pipe material _p whose initial diameter is considerably larger than the final mean diameter of the grooved pipe φ. In the application example shown in Pig «2, the initial outside diameter«? diameter of the smooth tube about 67 mm, and the average effective diameter that is ,, _o the means between the inner and outer diameter, was grooved in the fertigerr ^

BATH ORIGINAL 009832 / Ö528

Tube about "31 mm. Thus, the diameter of the ear material reduced to approximately half.

The drawings and the foregoing description give such a complete, clear and accurate picture of the invention that that hereafter any person skilled in the art will be able to implement the invention practical to use. . . -

Claims: 009832/0528

Claims (8)

PAIEHT A. H SPEU C H E 1. Process for forming thin-walled pipes with 'deep longitudinal grooves, thereby g e k e η η 'ζ e i c h η e i>. , that this Pipe is initially provided between outwardly projecting ribs progressively with longitudinal grooves that the Wall of the ..pipe is progressively bent without the largest outer diameter of the pipe is reduced considerably, and that thereafter the outer diameter of the pipe progressively becomes significant is reduced in size and the hats are deepened and shaped until the desired dimensions are reached *. 2. The method according to claim 1, characterized in g. e k e η η ζ e i without t that the hats initially generated thereby be that the pipe material is pulled through an annular space which is brought in by a first drawing tool protruding sections for shaping hats and a grooved first mandrel is delimited, 3 »Method according to claim 2, characterized in that g e k e η η ζ e i c h η e t that the hats thereby deepened and in their final shape can be brought through that the RöhrmatexiHl a considerably smaller annular space is pulled through, which is drawn by a second drawing tool with a grooved opening and a grooved second mandrel is delimited, 009832/0528 4. Drawing tool construction suitable for creating grooves in the form of an assembled drawing tool, marked by a first annular portion (36) with an opening (64) facing radially inward advising projections (42) serving for forming from below, and one within the first die section arranged first grooved mandrel section (76), wherein the drawing tool construction is one of the first drawing tool section immediately adjacent second drawing tool portion 'comprises an opening (67), the diameter of which is considerably smaller than the opening of the first drawing tool section, with the second drawing machine part inwardly projecting parts (68) serving for forming grooves, and wherein in the second cutting tool section a second grooved mandrel section angeora.i ^ t is.t " .5. Drawing tool construction according to Claim 4, characterized in that characterized «that the first drawing tool section an annular body (36) with radial openings (38) comprises, in which in the longitudinal direction adjustable rods (40) arranged airidj. these rods for molding Grooves serving 5 rounded ends protruding into the opening (42) have. _{6. Drawing tool construction} according to claim 4 »thereby wJ eke η η aei ο h η et» that the second Ziehwerkaeugubschnitt comprises an annular body (58), the i # axial • ü'luchtung mib the first Ziehwerkzeugabi.ioimitt connected with this iiütj, wherein the second drawing tool section: .-. ·> ■ <.-. jcuö its parts used for forming grooves and the first 00 9 832/0528 BATH Drawing tool section has a conical opening (66), 7. " _{Drawing tool construction:} according to claim 6, characterized in that the grooved second mandrel section (68) has a substantially constant cross-sectional shape over the entire length of the second drawing tool section. " 8. drawing tool construction according to claim 4, characterized ge k. e η η ζ e i c h η e t that the first grooved mandrel section (76) grooved on the support (34) for the second Dornäbschnitt is rotatable, and that a device (80) is provided to the first mandrel section in the correct Define the angular position in relation to the second mandrel section. 9 · Drawing tool construction according to claim 4 »characterized in that the first mandrel section is designed as a capped annular body made of a resin material, ζ _β Β _β ljylon, on its outside. 009832/052 L e r s e i t e