Continuous production device and manufacturing method for spiral welded steel pipe of combined structure

Abstract

A continuous production device for a spiral welded steel pipe of a combined structure, comprising a delivery mechanism, a spiral rolling mechanism, a guide carrier roller, and a welding mechanism. A first composite steel strip is delivered by the delivery mechanism; a vertical steel strip is rolled outwards into a round shape by the spiral rolling mechanism; the welding mechanism is used for welding a spiral joint between an upper steel strip that has just been rolled into a round shape and the previous section of steel strip which has become a pipe body; a lower steel strip is guided by a guide carrier roller to be attached to the vertical steel strip of the first composite steel strip that has passed through a pilot roller; and when the attachment point passes through a rounding press roller, the joint between the first composite steel strip and the lower steel strip is welded by means of the welding mechanism, achieving continuous spiral rolling and welding. The welding point between the first composite steel strip and the lower steel strip is located behind the rounding press roller, that is, behind a plastic deformation point of the first composite steel strip; in this case, the first composite steel strip has completed plastic deformation in the rolling process, and the lower steel strip does not need to be stretched when being rolled, thereby avoiding tensile deformation.

Description

Continuous production equipment and manufacturing method of composite structure spiral welded steel pipe Technical Field

[0001] The present invention relates to the technical field of steel pipe welding, and in particular to continuous production equipment and a manufacturing method for a combined structure spiral welded steel pipe. Background Art

[0002] This application designs a composite structural steel pipe, reference application number: 202211023603.4, title: A composite structural wall large diameter spiral welded steel pipe and its manufacturing method prior application, the steel pipe is made of a continuous composite steel strip after spiral rolling and welding, wherein the composite steel strip is made of two upper and lower flat steel strips with a vertical steel strip (reinforcement rib) welded in the middle, as shown in Figures 1 and 2. During the spiral rolling process of the above-mentioned composite steel strip, the vertical steel strip and the lower steel strip (outer steel strip) will produce large plastic deformation, which will cause the following problems:

[0003] 1. After the composite steel strip consisting of the upper steel strip, the lower steel strip and the vertical steel strip are directly welded together, the cross-sectional moment is much larger than that of a single-layer steel plate, and the power requirement of the equipment is too high;

[0004] 2. After the composite steel strips are welded together, when they are rolled, the vertical steel strips are subjected to too much radial pressure due to the tensile deformation of the outer steel strips during rolling, which may cause unstable buckling, especially the pressure exerted by the lower steel strip (outer steel strip) on the vertical steel strips during plastic deformation and stretching.

[0005] 3. The lower steel belt will have a large stretch and plastic deformation, and the weld between the lower steel belt and the vertical steel belt will be stretched and damaged;

[0006] 4. After the pipe is formed, the connection between the lower steel belt and the vertical steel belt will form a convex spiral pattern, and the surface of the corrugated pipe will be uneven, as shown in Figure 3;

[0007] 5. The upper steel belt (inner steel belt) shrinks severely. When the upper steel belt is thin, it may buckle and wrinkle.

[0008] Summary of the Invention

[0009] Purpose of the invention: In order to overcome the shortcomings of the background technology, the first purpose of the present invention is to disclose a continuous production equipment for combined structure spiral welded steel pipes; the second purpose is to disclose a method for manufacturing combined structure spiral welded steel pipes using the above-mentioned continuous production equipment.

[0010] Technical solution: The present invention discloses a continuous production equipment for a combined structure spiral welded steel pipe, wherein the combined structure spiral welded steel pipe is formed by continuous rolling and welding of a composite steel strip, wherein the composite steel strip is formed by welding an upper steel strip, a lower steel strip and a vertical steel strip therebetween arranged in parallel, wherein the upper steel strip and the vertical steel strip are welded to first form a first composite steel strip, wherein the rolling equipment comprises a delivery mechanism, a spiral rolling mechanism, a guide roller and a welding mechanism, wherein the spiral rolling mechanism comprises a leading roller, a pressing roller and a rolling roller behind the delivery mechanism, wherein the first composite steel strip is delivered by the delivery mechanism, and the vertical steel strip is rolled outward by the spiral rolling mechanism, wherein the welding mechanism welds the spiral joint between the upper steel strip of the first composite steel strip that has just passed the pressing roller position and the upper section of the upper steel strip that has become the pipe body, wherein the lower steel strip is guided by the guide roller and fitted with the vertical steel strip of the first composite steel strip that has passed the leading roller, wherein when the fitting point passes the pressing roller, that is, the plastic deformation point of the first composite steel strip, the joint between the first composite steel strip and the lower steel strip is welded by the welding mechanism, and continuously spirally rolled and welded.

[0011] Furthermore, the guide roller and the lower steel belt are arranged laterally below the spiral winding mechanism, at a position after the first composite steel belt completes the full-circle spiral winding. The lower steel belt is led out through the guide roller and attached to the first composite steel belt after the full-circle winding is completed, and the joint between the first composite steel belt and the lower steel belt is welded.

[0012] Furthermore, the guide roller and the lower steel belt are arranged above the tube body on which the first composite steel belt has completed spiral rolling. The lower steel belt is led out through the guide roller and attached to the first composite steel belt that has completed rolling, and the joint between the first composite steel belt and the lower steel belt is welded.

[0013] Furthermore, the guide roller is composed of multiple rollers with adjustable angles, whose angles match the forward direction of the first composite steel strip. The upper steel strip is close to the outer wall of the roller. The rollers are arranged at intervals, and the gaps between them are used to pass and clamp the guide vertical steel strip.

[0014] Furthermore, the winding roller is composed of a plurality of rollers with adjustable angles, the angles of which match the forward direction of the first composite steel strip, the upper steel strip is close to the outer wall of the roller, the rollers are arranged at intervals, and the gaps at the intervals are used to pass and clamp the guide vertical steel strips and assist in rolling the vertical steel strips.

[0015] Furthermore, the continuous production equipment also includes a clamping and guiding device for stabilizing the vertical steel strip, one or more of which are arranged in the circumferential direction of the spirally rolled first composite steel strip.

[0016] Furthermore, the clamping guide device includes a guide shaft, which is provided with a clamping guide wheel corresponding to the vertical steel strip on the first composite steel strip through a guide bearing sleeve, and a positioning sleeve 705 is set between adjacent clamping guide wheels 703. A clamping groove for embedding the vertical steel strip is provided on the outer periphery of the clamping guide wheel, and the angle of the clamping guide device matches the angle of the first composite steel strip.

[0017] The clamping and guiding device may also be composed of a plurality of rollers with adjustable angles, the angles of which match the advancing direction of the first composite steel strip. The rollers are arranged at intervals, and the gaps at the intervals are used to clamp and guide the vertical steel strip.

[0018] Furthermore, after the combined structure spiral welded steel pipe is formed, the spiral weld of the upper steel strip is staggered with the spiral weld of the lower steel strip.

[0019] Furthermore, the width of the lower steel strip matches the size of the first composite steel strip.

[0020] A method for manufacturing a composite structure spiral welded steel pipe, using the above-mentioned continuous production equipment for composite structure spiral welded steel pipe, comprises the following steps:

[0021] S1. Unwinding an upper steel strip from a steel coil and welding vertical steel strips onto the upper steel strip to form a first composite steel strip;

[0022] S2. Flip the first composite steel strip 180° so that the vertical steel strip faces downward, and then deliver it to the spiral coiling mechanism by the delivery mechanism. The above steel strip serves as the inner coil, and the vertical steel strip is coiled outward.

[0023] S3, welding the spiral seam between the upper steel strip of the first composite steel strip and the upper steel strip of the previous section that has become the pipe body, which has just passed the position directly below the rounding roller, i.e., the position where the first composite steel strip has completed plastic deformation;

[0024] S4, guiding the lower steel strip through the guide rollers and laminating it with the first composite steel strip;

[0025] S5. After the lower steel strip is bonded to the first composite steel strip and the bonding point passes through the rounding roller, a welding gun is inserted into the cavity between the upper and lower steel strips and the vertical steel strip to weld the weld seam in the cavity;

[0026] S6. Weld the spiral seam between the rolled lower steel strip and the upper lower steel strip that has become the pipe body at the top of the pipe body.

[0027] Beneficial effects: Compared with the prior art, the advantages of the present invention are:

[0028] 1. The first composite steel strip is first rolled into a circle and then welded to the lower steel strip. The welding point with the lower steel strip is located behind the rounding roller. At this time, the first composite steel strip has completed the plastic deformation after rolling.

[0029] 2. The lower steel belt (outer steel plate) does not need to be stretched any more and will not produce tensile deformation. In addition, the production line does not need to provide additional tensile force, and its power demand is reduced;

[0030] 3. There will be no spiral corrugated deformation on the surface of the tube after forming;

[0031] 4. The weld between the lower steel strip and the vertical steel strip will not be stretched and will not be damaged;

[0032] 5. The welds of the lower steel strip and the vertical steel strip are inside the structure, and the joints will not form the spiral weld convex pattern of the steel pipe;

[0033] 6. The height of the vertical steel strip can be increased, the thickness can be reduced, and it is not easy to deform;

[0034] 7. The lower steel strip is a whole plate with the same width as the upper steel strip, rather than a stripped plate. The weld between the vertical steel strip and the outer tube wall is in the inner cavity of the double-layer tube wall, which reduces the visible weld on the outer wall, ensuring the strength of the tube body while making the appearance of the tube body beautiful.

[0035] 8. The vertical steel belt can realize clamping and guiding in multiple positions and is not easy to buckle;

[0036] 9. It can ensure that the vertical steel strip is perpendicular to the inner and outer pipe walls, which is beneficial to the welding quality of the spiral joint;

[0037] 10. The guide rollers and lower steel belt can be moved out from under the coiling mechanism, and the entire production line does not need to be dug or lifted high;

[0038] 11. The space is easy to arrange fixtures and equipment with different functions;

[0039] 12. Easy to monitor the quality of the welds between the inner steel strip and the vertical steel strip during processing;

[0040] 13. It is easy to set shear nails and other components on the upper steel belt, lower steel belt and vertical steel belt;

[0041] 14. The propulsion force of this device acts on the first composite steel belt. The cross-section of the first composite steel belt is a "T"-shaped structure. Its cross-sectional moment of inertia is large, and it can withstand a large pushing force during pushing and is not easy to buckle. At the same time, the pushing wheel can form full contact with the upper steel belt, so that the delivery clamping area is larger and the pushing force that can be applied is also larger. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] FIG1 is a cross-sectional view of a composite steel strip welded as a whole;

[0043] FIG2 is a schematic diagram of a spirally rolled composite steel strip welded as a whole;

[0044] Figure 3 is a schematic diagram of the convex spiral pattern structure;

[0045] FIG4 is a structural diagram of a continuous production equipment form 1 of the present invention;

[0046] FIG5 is a schematic top view of the intersection of the guide roller and the first composite steel strip structure of the present invention;

[0047] FIG6 is a schematic structural diagram of the clamping guide device of the present invention;

[0048] FIG7 is a structural diagram of a second continuous production equipment according to the present invention;

[0049] FIG8 is a structural diagram of a third continuous production device according to the present invention;

[0050] FIG9 is a schematic structural diagram of a first composite steel strip according to the present invention;

[0051] FIG10 is a schematic structural diagram of the first composite steel belt, the lower steel belt and the guide rollers of the present invention;

[0052] FIG11 is a schematic diagram of welding points of the first composite steel strip and the lower steel strip according to the present invention;

[0053] FIG12 is a schematic diagram of the processing of the present invention when the guide rollers and the lower steel strip are positioned laterally below the roll forming mechanism;

[0054] FIG13 is a top view of a third continuous production apparatus according to the present invention;

[0055] FIG14 is a top view of the winding roller and the winding roller wheel of the present invention. DETAILED DESCRIPTION

[0056] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0057] The continuous production equipment of the combined structure spiral welded steel pipe as shown in Figure 4, the combined structure spiral welded steel pipe is formed by continuously rolling and welding a composite steel strip, and the composite steel strip is formed by welding an upper steel strip 1, a lower steel strip 2 and a vertical steel strip 3 arranged in parallel therebetween. The upper steel strip 1 and the vertical steel strip 3 are welded to first form a first composite steel strip.

[0058] The upper steel strip 1 and the lower steel strip 2 have the same size, so that the width of the lower steel strip 2 matches the size of the first composite steel strip.

[0059] The rolling equipment includes a delivery mechanism 4, a spiral rolling mechanism 5, a guide roller 6 and a welding mechanism. The spiral rolling mechanism 5 includes a leading roller 501, a pressing roller 502 and a rolling roller 503 behind the delivery mechanism 4. The first composite steel strip is delivered by the delivery mechanism 4 and rolled outward by the spiral rolling mechanism 5. The welding mechanism welds the spiral joint between the upper steel strip 1 of the first composite steel strip that has just passed the pressing roller 502 and the upper steel strip of the previous section that has become the tube body. The lower steel strip 2 is guided by the guide roller 6 to fit with the vertical steel strip 3 of the first composite steel strip that has passed the leading roller 501. When the fitting point passes the pressing roller 502, that is, the plastic deformation point of the first composite steel strip, the joint between the first composite steel strip and the lower steel strip is welded by the welding mechanism, and continuously spirally rolled and welded.

[0060] As shown in FIG5 , the guide roller 501 is composed of a plurality of rollers arranged at intervals and having adjustable angles. The angles thereof match the advancing direction of the first composite steel strip. The upper steel strip is in close contact with the outer walls of the rollers. The rollers are arranged at intervals, and the gaps between the rollers are used to pass through and clamp the guide vertical steel strip 3.

[0061] The winding roller 503 is composed of a plurality of rollers with adjustable angles that can be arranged at intervals. The angle thereof matches the forward direction of the first composite steel strip. The upper steel strip is close to the outer wall of the roller. The rollers are arranged at intervals. The gaps at the intervals are used to pass and clamp the guide vertical steel strip 3 and assist in winding the vertical steel strip.

[0062] As shown in Figure 6, the continuous production equipment also includes a clamping guide device 7 for stabilizing the vertical steel strips 3. One or more clamping guide devices are arranged circumferentially around the spirally wound first composite steel strip. The clamping guide device 7 includes a guide shaft 701, which is fitted with clamping guide wheels 703 corresponding to the vertical steel strips 3 on the first composite steel strip via guide bearings 702. Positioning spacers 705 are positioned between adjacent clamping guide wheels 703. The outer circumference of each clamping guide wheel 703 defines a clamping groove 704 for the vertical steel strips 3 to fit into. The angle of the clamping guide device matches the angle of the first composite steel strip.

[0063] The clamping and guiding device may also be composed of a plurality of rollers with adjustable angles, the angles of which match the advancing direction of the first composite steel strip. The rollers are arranged at intervals, and the gaps at the intervals are used to clamp and guide the vertical steel strip.

[0064] Considering that the lower steel strip is located directly below the composite steel strip being rolled, the space at this location is narrow. It is necessary to set up clamping and guiding devices to prevent deformation of the vertical reinforcement during processing, and to set up multiple welding guns to interfere with each other. In addition, the lower steel coil is directly below the rolling and forming device, and a deep pit needs to be dug to place the steel coil, which also makes it difficult to hoist the steel coil into place. In addition, the deformation and quality of the weld between the upper steel strip of the upper section of the composite steel strip and the vertical steel strip after rolling and spiral rolling cannot be inspected in real time. Secondly, after spiral rolling, the verticality of the spiral reinforcement to the inner and outer pipe walls may change, which may affect the overall performance of the structure.

[0065] Further improvements are proposed for the continuous production equipment of spiral welded steel pipes based on the above-mentioned combined structure.

[0066] Improvement 1: As shown in Figure 7, the guide roller 6 and the lower steel belt 2 are arranged above the tube body on which the first composite steel belt has completed spiral rolling. The lower steel belt 2 is led out through the guide roller 6 and attached to the first composite steel belt that has completed rolling, and the joint between the first composite steel belt and the lower steel belt 2 is welded.

[0067] Improvement 2: As shown in Figures 8 and 13, the guide roller 6 and the lower steel strip 2 are arranged laterally below the spiral winding mechanism 5, at a position after the first composite steel strip completes the full-circle spiral winding. The lower steel strip 2 is led out through the guide roller 6 and attached to the first composite steel strip after the full-circle winding is completed, and the joint between the first composite steel strip and the lower steel strip 2 is welded.

[0068] The production method of the continuous production equipment of the combined structure spiral welded steel pipe based on the second improvement includes the following steps:

[0069] S1, unwinding an upper steel strip 1 from a steel coil, and welding a vertical steel strip 3 to the upper steel strip 1 to form a first composite steel strip, as shown in FIG9 ;

[0070] S2. Flip the first composite steel strip 180° so that the vertical steel strip 3 faces downward, and then deliver it to the spiral winding mechanism 5 by the delivery mechanism 4. The steel strip 1 is used as the inner coil, and the vertical steel strip 3 is rolled outward, as shown in Figures 8, 12, 13 and 14;

[0071] S3, welding the spiral seam between the upper steel strip 1 that has just been rolled and the upper steel strip of the previous section that has become the pipe body, as shown in FIG12;

[0072] S4, the lower steel strip 2 is introduced by the guide roller 6 and is bonded to the first composite steel strip that has been rolled;

[0073] S5. After the lower steel strip 2 is bonded to the first composite steel strip and the bonding point passes through the rounding roller, a welding gun is inserted into the cavity between the upper and lower steel strips and the vertical steel strip to weld the weld seam in the cavity, as shown in Figures 12 and 13;

[0074] S6. The spiral seam between the rolled lower steel strip 2 and the upper section of the lower steel strip 2 that has become the pipe body is welded. As shown in FIG13 , after the combined structure spiral welded steel pipe is formed, the spiral weld of the upper steel strip 1 is staggered with the spiral weld of the lower steel strip 2.

Claims

1. A continuous production equipment for a composite structure spiral welded steel pipe, wherein the composite structure spiral welded steel pipe is formed by continuous rolling and welding of a composite steel strip, characterized in that: The composite steel strip is formed by welding an upper steel strip (1), a lower steel strip (2) and a vertical steel strip (3) arranged in parallel. The upper steel strip (1) and the vertical steel strip (3) are welded to form a first composite steel strip. The rolling device comprises a delivery mechanism (4), a spiral rolling mechanism (5), a guide roller (6) and a welding mechanism. The spiral rolling mechanism (5) comprises a leading roller (501) at the rear of the delivery mechanism (4), a pressing roller (502) and a rolling roller (503). The first composite steel strip is delivered by the delivery mechanism (4) and is passed through the spiral rolling mechanism. (5) The vertical steel strip is rolled outward to form a circle, and a welding mechanism is used to weld the spiral joint between the upper steel strip (1) of the first composite steel strip that has just passed the rounding roller (502) and the upper steel strip of the previous section that has become the tube body. The lower steel strip (2) is guided by the guide roller (6) to fit the vertical steel strip (3) of the first composite steel strip that has passed the leading roller (501). When the fitting point passes the rounding roller (502), that is, the plastic deformation point of the first composite steel strip, the joint between the first composite steel strip and the lower steel strip is welded by the welding mechanism, and the spiral rolling and welding are continued.

2. The continuous production equipment of the combined structure spiral welded steel pipe according to claim 1 is characterized by: The guide roller (6) and the lower steel strip (2) are arranged at a position below the spiral rolling mechanism (5) on the side thereof, after the first composite steel strip has completed full-circle spiral rolling. The lower steel strip (2) is led out through the guide roller (6) and attached to the first composite steel strip after the full-circle spiral rolling is completed, and the joint between the first composite steel strip and the lower steel strip (2) is welded.

3. The continuous production equipment of the combined structure spiral welded steel pipe according to claim 1 is characterized by: The guide roller (6) and the lower steel strip (2) are arranged above the tube body on which the first composite steel strip has been spirally rolled; the lower steel strip (2) is led out through the guide roller (6) and attached to the first composite steel strip that has been spirally rolled; and the joint between the first composite steel strip and the lower steel strip (2) is welded.

4. The continuous production equipment of the combined structure spiral welded steel pipe according to claim 1 is characterized by: The guide roller (501) is composed of a plurality of rollers with adjustable angles, the angle of which matches the advancing direction of the first composite steel belt, the upper steel belt is in close contact with the outer wall of the roller, the rollers are arranged at intervals, and the gaps at the intervals are used to pass and clamp the guide vertical steel belt (3).

5. The continuous production equipment of composite structure spiral welded steel pipe according to claim 1, characterized in that: The rolling roller (503) is composed of a plurality of rollers with adjustable angles, the angle of which matches the forward direction of the first composite steel strip. The upper steel strip is close to the outer wall of the roller. The rollers are arranged at intervals, and the gaps at the intervals are used to pass and clamp the guiding vertical steel strip (3) and assist in rolling the vertical steel strip.

6. The continuous production equipment of composite structure spiral welded steel pipe according to claim 1, characterized in that: The continuous production equipment also includes a clamping guide device (7) for stabilizing the vertical steel strip (3), one or more of which are arranged in the circumferential direction of the spiral roll of the first composite steel strip.

7. The continuous production equipment of the combined structure spiral welded steel pipe according to claim 6, characterized in that: The clamping guide device (7) comprises a guide shaft (701), and the guide shaft (701) is provided with a clamping guide wheel (703) corresponding to the vertical steel strip (3) on the first composite steel strip through a guide bearing (702), and a positioning sleeve (705) is set between adjacent clamping guide wheels (703). The outer periphery of the clamping guide wheel (703) is provided with a clamping groove (704) for the vertical steel strip (3) to be embedded, and the angle of the clamping guide device matches the angle of the first composite steel strip.

8. The continuous production equipment of composite structure spiral welded steel pipe according to claim 6, characterized in that: The clamping and guiding device (7) is composed of a plurality of rollers with adjustable angles, the angles of which match the advancing direction of the first composite steel strip. The rollers are arranged at intervals, and the gaps at the intervals are used to clamp and guide the vertical steel strip (3).

9. The continuous production equipment of composite structure spiral welded steel pipe according to claim 1, characterized in that: After the combined structure spiral welded steel pipe is formed, the spiral weld of the upper steel strip (1) and the spiral weld of the lower steel strip (2) are staggered.

10. The continuous production equipment of composite structure spiral welded steel pipe according to claim 1, characterized in that: The width of the lower steel strip (2) matches the size of the first composite steel strip.

11. A method for manufacturing a composite structure spiral welded steel pipe, characterized in that: The continuous production equipment of the combined structure spiral welded steel pipe according to claim 1 comprises the following steps: S1, unwinding an upper steel strip (1) from a steel coil, and welding a vertical steel strip (3) to the upper steel strip (1) to form a first composite steel strip; S2, the first composite steel strip is turned over 180 degrees, so that the vertical steel strip (3) faces downward, and then delivered to the spiral rolling mechanism (5) by the delivery mechanism (4), with the above steel strip (1) as the inner ring, and the vertical steel strip (3) is rolled outward; S3, welding the spiral joint between the upper steel strip (1) of the first composite steel strip that has just passed the position directly below the rounding roller (502) and the upper steel strip of the previous section that has become the pipe body; S4, introducing the lower steel strip (2) through the guide roller (6) and laminating it with the first composite steel strip; S5, after the lower steel strip (2) is bonded to the first composite steel strip and the bonding point passes through the rounding roller, a welding gun is inserted into the cavity between the upper and lower steel strips and the vertical steel strip to weld the welding seam in the cavity; S6. A spiral joint is welded between the rolled lower steel strip (2) and the upper section of the lower steel strip (2) that has become the pipe body at the top of the pipe body.

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