GB2027373A

GB2027373A - Apparatus for Producing Helical Seam Pipes

Info

Publication number: GB2027373A
Application number: GB7832533A
Authority: GB
Original assignee: CSEPEL MUEVEK EGYEDI GEPGYARA
Current assignee: CSEPEL MUEVEK EGYEDI GEPGYARA
Priority date: 1978-08-08
Filing date: 1978-08-08
Publication date: 1980-02-20
Also published as: GB2027373B

Abstract

An apparatus for producing helical seam pipes having an automatic monitoring unit to ensure the required pipe diameter comprises strip bending rollers 12 which can be displaced in a vertical and a lateral direction relative to the axis of the pipe and radially movable sliders 64 carrying calibrating rollers 13-17 arranged around the pipe connected to a drive unit 36. A sensor 69 is positioned on the pipe between the last calibrating roller 17 and an internal spot welder and controls the adjustment of the bending rollers. <IMAGE>

Description

SPECIFICATION Apparatus for Producing Spiral Pipes from Band Steel or Plate The invention relates to an apparatus for producing spiral pipes from metal band, or plate, which consists of a pipe-bending unit functioning on the principle of the three-roller type plate rolling machine, and of an external calibrating unit.

The piper shaping units of the equipment used for the manufacture of spiral welded pipes, generally consist of pipe bending and calibrating units. The roller-type pipe bending unit contains-in practically every known equipment-three shaping rollers, or roller groups, one of them arranged in side and two of them outside the pipe.

The calibrating frame within the calibrating unit contains adjustable rollers, which shape the final size of the pipe. The calibrating frame may be arranged inside the pipe [see for instance the GFR patent specification No. 2 053 266] or placed outside around the mantle of the pipe [ see for instance the Swiss patent specifications No. 407 016 and 441 200].

Since adjustment of the shaping system must be altered in the process of shaping, the recent types of equipment can be developed in such a way, that the rollers both in the shaping unit and calibrating unit can be quickly reset. Such equipment is described for instance in the GFR patent specification No. 1 752 513. The rollers in the calibrating frame of this equipment move on slides, which are set into the appropriate position by synchronized feed shafts. The driving chain of the feed shafts is connected with the drive performing the vertical movement of the calibrating frame.

In the production of the welded spiral pipes it is fundamental that the band shaping should be carried out with flexible deformation, but the round-bent band should keep the required diameter without welding as much as possible.

This way the internal stresses arising in the pipe mantle can be avoided, which otherwise reduce the loadability of the coil pipe to a great extent.

The presence of such stresses can be simply demonstrated by slitting the welding pipe, since the pipe comes apart, or contracts after its being slit.

Since quality and dimensions of the plate used for pipe production may vary between certain limits, corrections are necessary in the process of shaping for the purpose that the pipe shaping should take place by practically plastic deformation, in order to obtain pipes of constant dimensions.

For this reason rollers of both the shaping and calibrating unit should be developed as to make the continuous and separate adjustment of the rollers possible during operation. The already mentioned equipment described by GFR patent specification No. 1 752 513 is not suitable for such adjustments during operation. Another disadvantage is that the intervention depends on the subjective judgement and practice of the operator. However, this is a clearly unsatisfactory solution in case of precise mass production.

The object of the present invention is an apparatus which attempts to eliminate the described disadvantages, so that it is possible to record continuously in the process of spiral welded pipe production whether adjustment of the rollers of the shaping and calibrating unit is necessary, and should the need arise, automatic adjustment.

According to the invention, the apparatus is provided with a sensor on the mantle section between the last calibrating roller and internal welding spot, which bears up on the shaped pipe mantle and is connected with the drive of the shaping unit via the indicator instrument, or control circle. The slides of the calibrating rollers in the calibrating unit are radially arranged in the calibrating frame and are connected with the drive through a driving chain which consists of shafts arranged tangentially in the calibrating frame, of bevel gear assembly at the shaft ends and of the connected toothed rolls with radially arranged shaft. Both sides of the slides are symmetrically fitted with threaded spindles parallel with the direction of setting, which are connected with the toothed roll via the uniaxial toothed wheel and driving chain.The threaded spindles are guided in the spindle nuts fixed to the calibrating frame.

The driving chain-connecting the threaded spindles on both sides of the slides-consits of the toothed wheels connected to the spindles, of the bevel gear pair containing the bevel gears fixed to common shaft with the internal toothed wheels, and of the lateral shaft perpendicular to the direction of setting, and connecting the bevel gear pairs.

A releasable clutch element, for instance a sliding gear is fitted into the driving chain between the slides of the drive and calibrating frame.

Thus above solution permits the fast and accurate adjustment of the calibrating unit as a relatively small structural unit. The uniform and reliable adjustment of the slides moving in the calibrating frame, as well as prevention of stresses can be ensured by movement with two parallel feed shafts.

The present invention will be further described, by way of example only, with reference to the accompanying drawings, in which:~ Figure 1 is a cross section of the apparatus according to the invention, Figure 2 is a longitudinal section of the shaping units, Figure 3 is a longitudinal section of a slide of the calibrating unit.

The apparatus shown in Figure 1 is the shaping and calibrating unit of such coil pipe welding machine, in which centreline of the plate running on the band preparation line, remains stationary at every band width, and variation of the band width takes place by setting the machine units on the preparation line laterally and symmetrically to this centreline. Base slides 2 and 3 move on the guide of base body 1 of the equipment, which are to be set when the plate width is adjusted in the position fixed by the plate edges to be welded.

Base slide 2 of the shaping unit is set with drive 4. The drive 4 moves the base slide 2 with the aid of the threaded spindle 6, and spindle nut 7, as shown in Figure 2. The threaded spindle 6 is embedded in base body 1, while spindle nut 7 is fixed to base slide 2.

Base slide 3 of the calibrating unit is moved by drive 5 with the aid of toothed whell 8, and toothed bar 9 fixed to base body 1.

The shaping unit shown in Figures 1 and 2 contains the shaping rollers 10, 11 and 12.

Shaping rollers 10 which are turnable around vertical axis are embedded in beam 18to be adjustable in groups into the running direction of the plate. Beam 18 is vertically displaceable in the guide of slide 19. Slide 19 is displaceable on the length exceeding the roller spacing in the axial direction of the pipe with the aid of threaded spindle 20, embedded in base slide 2 and with spindle nut 21 fixed to slide 19.

The beam 18 is moved by drive 22 in vertical direction. Its shaft 23 through universal joints 24 and sleeve 25 drives the worm assembly 26 embedded in slide 19. Wheels of the worm assembly 26 rotate the threaded spindles 27, which lower, or lift the beam 18 through the spindle nuts 28 fixed in it.

A similar mechanism moves the beam 29 carrying the rollers 12 in the guides of lateral slide 30. Lateral slide 30 is moved on the guide of slide 31 by spindle nuts 34 fixed to it, and by threaded spindles 32 embedded in slide 31. The worm wheels 35 are fixed onto threaded spindles 32.

The pertaining worms 36 are connected with each other, ensuring the synchronous rotation of threaded spindles 32.

The bending span of the three-roller shaping unit can be reduced or increased by varying the position of lateral slide 30. The setting is facilitated by scale 33. The shaping rollers 11 are embedded in groups being rotable around vertical shaft in console 37. The height of these shaping rollers 11 is not variable, their lower component determines position of the internal mantle surface of the manufactured pipe.

The various plate# thicknesses and various curvatures pertaining to the various pipe diameters can be set by varying the height of shaping rollers 10 and 12. The position of the shaping rollers 10 and 12, thus diameter of the pipe to be shaped can be delicately varied at any time without stopping the production process.

Fixing or locking after the setting is unnecessary.

The equipment according to the invention is provided with a feeler unit 69 to be seen in Fig. 1.

Its sensor bears up on the pipe mantle shaped in the shaping unit.

If variation in the balance of the internal stresses produces increase of the diameter, the sensor feels a bulge of oval character, and in case of diameter reducing tendency, the sensor moves in opposite direction, due to displacement of the pipe axis into the running direction of the plate.

This rotates the drive 22 of the shaping unit through the control circle into the appropriate direction and it changes the position of the shaping rollers 12, to ensure restoration of the equilibrium.

The calibrating unit is built into base slide 3. It has two columns provided with vertical guides 38. On these the calibrating frame 39 is displaceable in vertical direction, on the upper part of which the worm wheel fitted spindle nut 42 is embedded. The spindle nut 42 turns on threaded spindle 41. The threaded spindle 41 is fixed to beam 40 connecting columns 38. Thus the calibrating frame 39 is suspended to beam 40 through the spindle-spindle nut connection in such a way, that by turn of spindle nut 42 height of calibrating frame 39 varies.

Since according to the description the lower component of the shaping rollers 11 determines the height for the lower component of the internal mantle surface of the pipe, the calibrating frame 39 is to be displaced in relation to this plane of reference, according to the wall thickness.

Regarding the external pipe diameter-fixed by calibrating rollers 13-17-as unchanged, with increase of the wall thickness, the calibrating frame 39 is to be displaced downwards with the value corresponding to the increases, or upwards in case of decreasing wall thickness.

On the other hand, if the pipe diameter is increased at the same wall thickness, position of the centreline too will change with AR increase of the inside radius of the pipe. The calibrating frame 39 is lifted with the value of AR, since the calibrating rollers 13-17 perform a concentric motion around the structural centre of the calibrating frame 39.

Reading of the plate thickness can be taken on scale 51. Scale 52 built together with the indicator showing the plate thickness is set to the scale value with aid of the adjusting device 53, which is calibrated for diameter. Value of the set diameter can be obtained with the aid of pointer 54 fixed to calibrating frame 39, or with pointer 68 of scale 67 on the calibrating frame 39 fixed to slide 64.

The calibrating frame 39 is moved by drive 43.

The kinematic chain is releasable by sliding gear 44 as a clutch. Drive 43 rotates shaft 46 too with the sliding gear 45 as a releasable unit, which is turn drives shaft 48 through worm gear 47.

Shafts 48 are connected with each other through bevel gear assembly 49, and ensure the synchronous driving of toothed rolls 50.

When the plate thickness is set on scale 51, sliding gear 45 as clutch is to be released. This way variation of the height of calibrating frame 39 is possible without the embedded calibrating rollers 13-17 settling in a position that fits a different diameter.

Movement of slides 64 in radial direction in the calibrating frame 39 is carried out by the toothed rolls 50, embedded in side boxes and in connection with each other.

Section of slide 64 of the equipment according to the invention is shown in Figure 3. At dimension variation, movement of the slides is synchronized with each other and after the required dimension variation they keep their position without fastening. For the radial adjustment the threaded spindle proved to be the best and most suitable, since this remains in the required position after the drive is stopped. Two threaded spindles 57a, 57b are used for the actuation in each slide 64, in order to ensure the motion free from stress and from tipping over.

Calibrating rollers 13-17 in the calibrating frame 39 of the equipment settle along an arc as shown in Figure 1. In the direction perpendicular to the plane of Figure 1, the calibrating rollers 13-17 are arranged in parallel lines on beams 55 [ see Figure 3]. Thus the calibrating rollers 13-17 bear up on the shaped pipe mantle along the components parallel with axis of the pipe.

Shafts 48 are arranged on one side of the calibrating frame 39, forming the elements of the driving chain coupled to drive 43. These are in positive coupling with each other through the bevel gear assembly 49, and likewise the toothed rolls 50 along slides 64 are coupled to them with positive coupling.

Elements of the driving chain ensuring movement of slide 64 are located within slide 64.

Toothed wheel 56 connected with toothed roll 50 is in uniaxial arrangement with spindle nut 66a, and it is connected to bevel gear pair 59 through toothed wheel 58. Spindle nut 57a is guided in spindle nut 66a connected by rigid coupling with calibrating frame 39 in such a way, that when the rotary motion is transmitted from toothed roll 50 to toothed wheel 56, the turn of threaded spindle 57a brings about the displacement of slide 64 at the same time. In the interest of realizing the safe setting, a threaded spindle 57b is fixed also to the other side of slide 64, guided similarly in spindle nut 66b fixed to calibrating frame 39. The motion is transmitted from toothed roll 50 to the other side of slide 64 through toothed wheels 56 and 58, bevel gear pair 59 and transmission shaft 60.

Here the bevel gear pair 61 transmits the motion to toothed wheels 62 and 65, which ensure the synchronized motion of threaded spindle 57b with threaded spindle 57. Movement with the two spindles is especially suitable for the slide to take the synchronized loads. The driving chain and structural dimensions are considerably simplified by arrangement of threaded spindles 57a and 57b in the moving slide 64.

Construction of the equipment according to the invention permits the pipe shaping unit of the spiral welding machine to function in a very wide range without irrealistically increasing the dimensions of the calibrating frame. Function in the diameter range of 400-1600 mm is a usual requirement for instance at such equipment. It this is solved in the traditional way, disproportionately large structural dimensions will occur, and weight of the equipment too will become excessive. This means that besides producing simpler and smaller equipment with the one according to the invention, the cost of production too will be reduced.

Claims

1. An apparatus for producing spiral pipes from steel band or plate, with shaping unit containing shaping rollers arranged at fixed height and shaping rollers displaceable in vertical direction and in lateral direction in relation to the axis of the produced pipe, and with shaping unit comprising calibrating rollers mounted on slides connected with common drive, arranged in adjustable calibrating frame on columns provided with vertical guide, wherein a feeler unit in contact with the pipe mantle is arranged on the mantle section between the last calibrating roller and internal welding spot, which is connected with the drive of the shaping unit through a display or control unit, the slides carrying the calibrating rollers being radially arranged in the calibrating frame and being connected with the drive of the calibrating unit through a driving chain, which consists of shafts tangentially arranged in the calibrating frame, bevel gear assembly at the shaft ends and toothed rolls with radially arranged shaft connected to the bevel gear assembly, both sides of the slides being provided with symmetrically arranged threaded spindles parallel with the direction of setting, which are connected to toothed roll via the uniaxial toothed wheel and driving chain, where the threaded spindles are guided in spindle nuts fixed by rigid coupling to the calibrating frame.

2. Apparatus as claimed in claim 1, wherein the driving chain connecting the threaded spindles arranged on both sides of the slides consists of the toothed wheels coupled to the threaded spindles, furthermore of bevel gear pairs containing bevel gear mounted on common shaft with the internal toothed wheels and of lateral shaft connecting the bevel gear pairs and perpendicular to the direction of setting.

3. Apparatus as claimed in claims 1 or 2, wherein the releasable clutch unit is fitted into the driving chain between the drive of the calibrating unit and slides of the calibrating frame.

4. Apparatus as claimed in claim 3, wherein the clutch element is sliding gear.

5. Apparatus for producing spiral pipes as claimed in claim 1 substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.

6. Spiral pipes produced by the apparatus as claimed in any one of the preceding claims.