JP2012529992A - Method and apparatus for monitoring and controlling a process when expanding a UOE steel pipe - Google Patents

Abstract

The present invention is a method and an apparatus for carrying out the method, and includes a tube expansion tool that can be introduced into a pipe and a support roller that supports the pipe to be straightened, and the pipe expansion tool is disposed on a draw bar. The tool head is supported by a tube with a radially expandable segment and a tube expansion tool which is arranged in the tool head and can be adapted to the radial position of the tube diameter to be corrected each time. And a head roller for the purpose. The head roller includes a measuring device for recording a supporting force that acts on the head roller during tube expansion. Further, a measurement value evaluation / monitoring unit and a signal unit for displaying a deviation from a predetermined tolerance threshold are provided.
[Selection] Figure 1

Description

  The present invention relates to a method as described in the preamble of claim 1 for monitoring and controlling the process when expanding a steel pipe made of UOE. In particular, the present invention relates to a pipe expanding method in which a pipe expander that expands in the radial direction is introduced into a pipe, and the pipe expander is pushed through the pipe in stages.

  The method referred to as UOE in the professional industry is the most frequently applied method for producing longitudinal seam welded large diameter pipes (Non-Patent Document 1). In this method, the edge of the flat steel plate is bent in the first step. Subsequent presses make the steel plate U-shaped with a circular press punch (U-press), and this steel plate is subsequently pressed into a circular grooved tube with an O-press machine with two closed molds. In many cases, the tube will be corrected by cold expansion (expansion) because the tube still does not meet the requirements for diameter, roundness and straightness after inner and outer surface welding. Such tubes are then welded into pipelines, which are used, for example, for oil or gas transport.

  In particular, since the demand for impact resistance of offshore laying pipes to which extremely high external pressure is applied is constantly increasing, the pipes must satisfy the increasingly stringent requirements regarding roundness tolerances.

  A steel pipe straightening device is known, for example, from US Pat. The pipe expander constituting this apparatus has a tool head that can be introduced into a pipe, and this tool head is arranged on a wedge-shaped polyhedron (wedge) arranged on a draw bar (tow bar) and its peripheral surface. And a plurality of segments. The draw bar is held by a bifurcated support on the side opposite to the tool head. The segments are moved radially away through the wedge for tube expansion, and the tube section will be expanded and corrected. The tube will then be corrected over its entire length via step expansion.

  A so-called head roller is provided in the lower region of the tube receiving head of the head receiving portion, and this head roller carries the tube expanding head during tube expansion and supports the tube on the tool side with it. The tube itself is supported by a support roller disposed in the direct action area of the head roller during the expansion.

  In order to correct various tube diameters, the head roller can change its radial position before expanding, i.e. the height distance relative to the expanding machine axis. In order to achieve an optimal tube geometry with respect to tube roundness and straightness after tube expansion, if the starting tube is completely circular and straight, the tube expander axis is aligned with the tube axis and the head roller distance is The radial position of the head roller is adjusted to match the straightened bore diameter. Deviations from this adjustment affect the overall tube geometry during expansion, thereby changing the roundness and straightness of the finished tube.

  In practice, the geometry that a tube has prior to expansion often deviates from ideal roundness and / or straightness. The head roller can also be used to cope with such deviations by appropriate adjustments in order to achieve optimal results with correction. This processing procedure is known and is also used to optimally adjust the head roller height position at the start of fabrication.

  Due to the influence of a wide variety of factors prior to expansion and because of the irregularities in the material properties, the geometric properties of the tube will vary during fabrication. As tolerances become increasingly tight, it is possible for the straightened tube to go out of tolerance under unfavorable conditions. In such a case, the tube has to be reworked by a laborious rework, for example by a hydraulic press cylinder.

German Patent Application Publication No. 2632672

Stahlrohr Handbuch, 12th edition, Vulkan Verlag Essen, 1995, pp. 139-143

  Therefore, an object of the present invention is to specify a method and an apparatus for monitoring the expansion process of a UOE production tube, in which changes in the tube starting geometry are recorded during expansion during production.

  Another challenge is to demonstrate a corresponding tube expansion process control that can react to recorded tube geometry changes.

  According to the present invention, the main problem is solved by measuring the supporting force acting on the head roller during tube expansion, evaluating it based on a predetermined target supporting force, and displaying if a deviation from a predetermined tolerance value is generated. The

  It is only possible with the method according to the invention to directly monitor the tube expansion process and thus ensure that the optimum tube geometry is achieved within the determined geometry requirements.

  As recognized in the experiment, the radial position of the head roller relative to the expander axis is ideally rounded as much as possible, especially when the blank already has a significant deviation from the required tube geometry. Degree and straightness are critical in achieving correction.

  As further confirmed in the experiment, a slight change in the radial position of the head roller already significantly affects the roundness and straightness of the expanded tube.

  In particular, experiments have shown that the forces measured by the head roller are clearly correlated with the tube geometry to be corrected. This means that the deviation of the tube geometry is correlated with the deviation in the head roller target force transition.

  When in a non-operating state, that is, when the tube expansion head is simply introduced into the tube, the head roller is added by the weight of the tube expansion tool, and this weight becomes the target force value of the support force.

  This target force value will be affected by the tube expansion process depending on the head roller position and the actual tube geometry.

  When the pipe to be expanded had a clear roundness deviation in advance, a clear deviation from the target force transition was identified within the experimental frame during the expansion. Depending on the degree of ellipticity, overpower or underpower was identified. In that case, re-measurement of the expanded tube would result in a corresponding deviation from the required tube geometry.

  Therefore, according to the present invention at the time of process monitoring, the supporting force acting on the head roller of the tube expander is measured during the tube expansion, compared with a predetermined tolerance value of the target supporting force, and a pass / fail judgment for keeping the geometric shape requirement is determined. Derived from the magnitude of the deviation.

  Then, by re-adjusting the radial head roller position according to the measured force deviation, the corrected geometry for the next tube can be appropriately affected.

  However, according to one advantageous configuration of the invention, it is also possible to use the measured deviation as a control amount for readjustment of the head roller, thereby affecting the tube geometry already during the expansion.

  As further detected in the experiment, the position of the support roller as well as the position of the head roller will affect the geometry of the expanded tube.

  Thus, in an advantageous configuration of the invention, the radial position of the support roller relative to the tube axis is additionally adjusted to meet the geometric requirements. Secondly, by suitably aligning the respective positions of the head roller and support roller, advantageously the roundness and straightness of the tube are affected in the sense of optimizing the tube geometry during expansion. Can affect.

  Other features, advantages and details of the invention will become apparent from the following description of the illustrated embodiment.

It is a schematic longitudinal cross-sectional view of the pipe expansion apparatus which concerns on this invention. 1 shows the apparatus of FIG. 1 in a cross-sectional view.

  The apparatus according to the present invention shown in FIG. 1 in a schematic longitudinal sectional view has a measuring device for measuring various forces acting on a head roller of a tube expanding tool during tube expansion.

  The tube expansion tool introduced into the tube 1 to be expanded comprises a tool head 10 with a segment 9 that can be expanded in the radial direction. The tool head 10 is arranged in a draw bar 11 which expands the segment 9 radially by axial movement via a wedge 14 between the draw bar 11 and the segment 9 and expands the tube. ing. Reference numeral 3 denotes a tube expander shaft or a tube shaft.

  The tool head 10 has a head roller 2, and the tool head 10 is supported by the expanding tube 1 by this head roller. The pipe 1 is supported by a support roller 12 disposed in the support portion 13 when the pipe is expanded.

  According to FIG. 2, the head roller 2 is supported in a support unit 4, which comprises a roller receiving part 7 and a displaceable support part 6. According to the present invention, the roller receiving portion 7 includes the measuring device 8, and the force acting on the head roller during the pipe expansion can be measured by this measuring device.

  As an example of the height displacement of the head roller 2, the support portion 6 is implemented as a wedge support portion and includes a displacement mechanism 5 formed of a hydraulic cylinder. With this displacement mechanism, the radial position of the head roller 2 can be adjusted through the sliding of the wedge support portion.

DESCRIPTION OF SYMBOLS 1 Pipe 2 Head roller 3 Tube expander axis | shaft or tube shaft 4 Support unit 5 Displacement mechanism 6 Support part 7 Head roller receiving part 8 Measuring apparatus 9 Segment 10 Tool head 11 Draw bar 12 Support roller 13 Support roller support part 14 Expanded wedge

Claims (11)

A method for monitoring a process when a steel pipe manufactured by a UOE method is expanded by a pipe expanding tool that can be introduced into the pipe, wherein the pipe expanding tool is disposed from a tool head that is arranged on a draw bar and can be expanded radially. The tool head is expanded with respect to the pipe being straightened by a head roller which is radially expanded by the tool head and which is arranged on the tool head and can be adapted to the pipe diameter to be corrected each time in the radial direction. Supported, the tube is supported by a support roller, and the head roller is added by a support force by a tube expansion process,
A method in which a support force acting on the head roller during tube expansion is measured, evaluated based on a predetermined target support force, and a display is made when a deviation from a predetermined tolerance value occurs.   The method of claim 1, wherein the radial position of the head roller is changed based on a deviation from the determined predetermined tolerance value, thereby affecting the tube geometry during tube expansion.   3. A method according to claim 1 or 2, characterized in that the radial position of the head roller is readjusted for at least the next tube to be expanded based on a deviation from the determined predetermined tolerance value.   4. The method according to claim 3, wherein if the deviation is confirmed, the position of the head roller is directly readjusted during the expansion.   5. A method according to any one of the preceding claims, characterized in that, in order to meet geometric requirements, the support roller is additionally adjusted in its radial position relative to the tube axis.   6. The method of claim 5, wherein the support roller is adjusted in conjunction with the head roller to meet geometric requirements. A device for carrying out the method according to any one of claims 1 to 6, comprising a tube expansion tool that can be introduced into the tube (1) and a support roller that supports the tube (1) to be straightened. 12), and the tube expanding tool comprises a tool head (10) disposed on the draw bar (11), and the tool head is disposed in the radially expandable segment (9) and the tool head. A head roller (2) for supporting the tube expansion tool with the tube (1), which can be adapted to a radial position to the tube diameter to be corrected each time.
The head roller (2) displays a measuring device (8) for recording a supporting force acting on the head roller (2) during tube expansion, a measured value evaluation and monitoring unit, and a deviation from a predetermined tolerance threshold value. And a signal unit.   8. The head roller (2) is supported in a support unit (4) comprising a roller receiving part (7) and a height-adjustable support part (6). Equipment.   9. Device according to claim 8, characterized in that the height-adjustable bearing part (6) is a wedge bearing part.   Device according to claim 8 or 9, characterized in that the height adjustment is effected via a displacement mechanism (5).   Device according to claim 10, characterized in that the displacement mechanism (5) is a manual, electric, hydraulic or pneumatic drive.

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