Correction method for welding angular deformation of H-shaped steel flange plate

Abstract

The invention relates to a method for correcting welding angular deformation of an H-shaped steel flange plate, which belongs to the technical field of steel structures and comprises the following operation steps of: 1, placing a correcting mold below a hydraulic machine, and mounting a correcting pressure head on the hydraulic machine; secondly, the H-shaped steel penetrates into the correcting mold, and the end of the H-shaped steel is flush with the end of the correcting mold; and thirdly, the hydraulic machine is started, the correction pressing head descends to make contact with the upper surface of the upper flange plate, and pressing force is applied. And fourthly, after the upper flange plate is corrected, a correction pressing head is lifted, and the H-shaped steel is lifted out and turned over by 180 degrees. And fifthly, the long H-shaped steel or the short H-shaped steel penetrates into the correcting mold, the hydraulic machine is started, and the correcting pressing head descends to make contact with the upper surface of the lower flange plate and exert pressing. And sixthly, after correction is completed, the component is hoisted out through a crane. And under the combined action of the correction mold and the correction pressure head, the correction of the angular deformation of the flange plate is realized. The device has the advantages of being convenient to use and free of damage to flange plate base metal in the correction process.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of steel structure, in particular to a kind of H-shaped steel flange plate welding angle deformation correction method. BACKGROUND

[0002] Welded H-shaped steel is composed of upper flange plate, web plate and lower flange plate, and the four longitudinal welds of H-shaped steel will produce welding angle deformation after welding due to the effect of welding shrinkage stress. In order to make the flatness (perpendicularity of flange plate and web plate) of upper and lower flange plates of H-shaped steel meet the design requirements, the angle deformation of flange plate of welded H-shaped steel needs to be corrected, and the correction is usually carried out by flange correcting machine. The flange correcting machine correction mechanism is composed of lateral pressing wheel, upper rolling wheel and lower rolling wheel, and the angle deformation of flange plate of welded H-shaped steel is corrected by rolling of upper and lower rolling wheels.

[0003] Although the flange correcting machine can correct the angle deformation of H-shaped steel, the flange plate needs to be closely attached to the upper and lower rolling wheels during the correction process, and the rolling wheels are all steel wheels. Therefore, under the action of rolling force and friction force, the surface of flange plate base material will be damaged to a certain extent. If the damage to the base material is too large, such as more than 0.5 mm, the base material damage after correction needs to be repaired and polished, which increases the processing procedures and time.

[0004] For short welded H-shaped steel members or components, such as corbels, the angle deformation after welding also needs to be corrected. At this time, due to the length limitation, it is not suitable to use flange correcting machine for correction, and flame correction method needs to be used for correction. However, the efficiency of flame correction is low, and the temperature of flame correction needs to be strictly controlled, otherwise the temperature is too high, which will damage the base material organization performance and affect the safety of structure use. SUMMARY

[0005] The present application mainly solves the problems existing in the prior art, and provides a kind of H-shaped steel flange plate welding angle deformation correction method, which realizes the correction of flange plate angle deformation under the joint action of correction die and correction pressure head. It has the advantages of convenient use and no damage to flange plate base material during correction. Flame correction method is not needed, and the correction efficiency is significantly improved.

[0006] The above technical problems of the present application are mainly solved by the following technical scheme: A kind of H-shaped steel flange plate welding angle deformation correction method, the H-shaped steel includes long H-shaped steel and short H-shaped steel, the long H-shaped steel and short H-shaped steel are composed of upper flange plate, web plate and lower flange plate, and the long H-shaped steel and short H-shaped steel are corrected by correction pressure head and correction die.

[0007] The correction method includes the following operation steps: Step 1: Place the straightening mold under the hydraulic press, install the straightening pressure head on the hydraulic press, with the straightening pressure head directly above the straightening mold, and the center line of the straightening pressure head and the center line of the groove on the upper cover plate of the straightening mold are on the same plane.

[0008] Step 2: Insert the long or short H-beams into the straightening mold, with the end of the H-beam flush with the end of the straightening mold.

[0009] Step 3: Start the hydraulic press, correct the pressure head to descend and contact the upper flange plate surface and apply clamping force.

[0010] Step 4: After the upper flange plate is straightened, the straightening pressure head is lifted, and the H-beam is lifted out and turned 180°.

[0011] Step 5: Insert the long or short H-beams into the straightening mold, start the hydraulic press, and lower the straightening pressure head to contact the upper surface of the lower flange plate and apply pressure.

[0012] Step 6: After the correction is completed, use a crane to lift the component out.

[0013] Preferably, when straightening long H-beams, the long H-beams are inserted and hoisted in through the end hole and slot on one side of the straightening mold, with the end of the long H-beams flush with the end of the straightening mold; the other end of the long H-beams is lifted by a crane hook to keep it horizontal.

[0014] As a preferred method, during the straightening process, the long H-beam is lifted by a crane and moved a certain distance to the end of the straightening mold, while the other end is still lifted by the crane hook to keep it horizontal.

[0015] As a preferred option, to ensure the corrective effect, the corrected length is not completely removed from the correction area, leaving about 200mm of length for further correction.

[0016] Preferably, the straightening mold includes a base plate with end plates at both ends and several stiffening ribs between the end plates. Each stiffening rib and end plate has a straightening groove for the H-beam to pass through and be positioned. The dimensions of the straightening groove are closely matched to the width of the lower flange of the H-beam, providing precise positioning and support.

[0017] Preferably, the base plate has side plates welded and fixed to the sides of the end plates at both ends. The stiffening ribs, end plates, and side plates form a three-dimensional frame for the mold, ensuring that the mold does not deform or become unstable under enormous pressure. The stiffening ribs and the upper part of the end plates have a pair of gap-distributed cover plates, the gap between which connects to the straightening groove. This allows the H-beam to be "inserted" into the straightening groove from above this gap. This is suitable for short H-beams; for long H-beams, this gap ensures that the pressure head will not interfere with the straightening mold throughout its stroke.

[0018] Preferably, the straightening pressure head consists of a horizontal pressure plate and a vertical pressure plate, and the straightening pressure head has a "T"-shaped structure. This ensures sufficient rigidity and strength, enabling the effective transmission of hydraulic press pressure to the workpiece. The ends of the vertical pressure plates are machined into an arc shape to reduce stress concentration: avoiding sharp edges from damaging the flange surface and preventing micro-cracks or indentations at the point of force application. Line contact is also achieved: when the arc surface contacts the flange plate as a line, it generates greater pressure than surface contact, making it easier for local metal to reach a yield state, thus achieving straightening with less pressure.

[0019] The present invention can achieve the following effects: This invention provides a method for correcting weld angle deformation of H-beam flange plates. Compared with existing technologies, this method achieves flange plate angle deformation correction through the combined action of a correction mold and a correction pressure head. It offers advantages such as ease of use and no damage to the flange plate base material during the correction process. It eliminates the need for flame straightening, significantly improving correction efficiency. Precise positioning is achieved through a dedicated mold, and the segmented, overlapping pressure application method solves the correction challenge for long workpieces. The arc design of the vertical pressure head and the overall box-shaped structure of the mold demonstrate excellent engineering practice.

[0020] Highly targeted: Specifically designed for H-shaped steel corner deformation, molded production, and precise positioning.

[0021] High efficiency: Compared with flame straightening, mechanical straightening is faster and requires relatively lower worker skills, and the process is easier to standardize.

[0022] Quality controllable: By controlling pressure, stroke and overlap, stable and repeatable correction results can be achieved.

[0023] Minimal impact on material properties: Cold straightening is performed near the material's yield point. As long as it is properly controlled, its impact on the mechanical properties (such as toughness) of the steel is far less than the local metallographic changes that flame straightening may cause.

[0024] Wide range of applications: By changing the straightening grooves of different sizes, it can be adapted to H-beams of different specifications. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the straightening structure of the long H-beam of the present invention.

[0026] Figure 2 This is a schematic diagram of the straightening structure for the short H-beam of the present invention.

[0027] Figure 3 This is a schematic diagram of the H-beam structure of the present invention.

[0028] Figure 4 This is a schematic diagram of the structure of the straightening mold of the present invention.

[0029] Figure 5 This is a schematic diagram of the upper pressure head of the present invention.

[0030] In the diagram: 1. Long H-beam, 2. Straightening head, 3. Straightening mold, 4. Short H-beam, 5. Upper flange plate, 6. Web plate, 7. Lower flange plate, 8. End plate, 9. Cover plate, 10. Rib plate, 11. Straightening groove, 12. Bottom plate, 13. Side plate, 14. Horizontal pressure plate, 15. Vertical pressure plate. Detailed Implementation

[0031] The technical solution of the invention will be further described in detail below through embodiments and in conjunction with the accompanying drawings.

[0032] Example: Figures 1-5 As shown, a method for correcting weld angle deformation of H-beam flange plates is disclosed. The H-beams include a long H-beam 1 and a short H-beam 4. Both the long H-beam 1 and the short H-beam 4 are composed of three plates: an upper flange plate 5, a web plate 6, and a lower flange plate 7. The long H-beam 1 and the short H-beam 4 are corrected using a correcting pressure head 2 and a correcting mold 3. The correcting pressure head 2 consists of a horizontal pressure plate 14 and a vertical pressure plate 15. The correcting pressure head 2 has a "T"-shaped structure, and the ends of the vertical pressure plate 15 are machined into arc shapes. The correcting mold 3 includes a base plate 12, with end plates 8 at both ends of the base plate 12. Three stiffening plates 10 are provided between the two end plates 8. The stiffening plates 10 and the end plates 8 are all provided with correcting grooves 11 for limiting the insertion of the H-beams. The bottom plate 12 has side plates 13 that are welded and fixed to the side of the end plate 8 at both ends. The stiffening plate 10 and the upper part of the end plate 8 have a pair of cover plates 9 with a gap distribution. The gap between the two cover plates 9 is connected to the straightening groove 11.

[0033] The correction method includes the following steps: Step 1: Place the straightening mold 3 under the hydraulic press, install the straightening pressure head 2 on the hydraulic press, with the straightening pressure head 2 located directly above the straightening mold 3, and the center line of the straightening pressure head 2 and the center line of the groove on the upper cover plate of the straightening mold 3 are on the same plane.

[0034] Perform equipment alignment: Ensure the centerline of the straightening pressure head 2 coincides with the centerline of the gap between the cover plate and the straightening mold 3. Purpose: To ensure that pressure is precisely applied to the exact center of the H-beam flange. If eccentric, it will cause uneven stress on the H-beam, which may result in secondary deformation such as lateral bending, complicating the straightening process.

[0035] Step 2: Insert the long H-beam 1 or the short H-beam 4 into the straightening mold 3, with the end of the H-beam flush with the end of the straightening mold 3. When straightening the long H-beam 1, insert it through the end hole and slot on one side of the straightening mold 3 and hoist it in, with the end of the long H-beam 1 flush with the end of the straightening mold; the other end of the long H-beam 1 is lifted by the crane hook and kept horizontal.

[0036] For H-beam feeding, short H-beam 4 is hoisted directly into the mold through the gap in the cover plate and placed in the straightening groove 11. Long H-beam 1 is fed using the method of "inserting one end and hoisting the other end".

[0037] Key point: Maintaining horizontality is the core technique for straightening long workpieces. If the H-beam is not horizontal, its own weight will generate an additional bending moment. This bending moment will be superimposed on the straightening pressure, making deformation prediction difficult and the straightening effect uncontrollable. Maintaining horizontality means eliminating the interference of its own weight bending moment, so that the straightening force is used only to overcome angular deformation.

[0038] Step 3: Start the hydraulic press, lower the straightening pressure head 2 to contact the upper surface of the upper flange plate 5 and apply clamping force. During the straightening process, the long H-beam 1 is lifted by a crane and moved a certain distance towards the end of the straightening mold 3, while the other end is still lifted by the crane hook to keep it horizontal. To ensure the straightening effect, the already straightened length is not completely moved out of the straightening area, leaving about 200mm for further straightening.

[0039] Segmented straightening (for long H-beams 1), operation: "press one segment, move one segment", ensuring "200mm overlap of the straightened portion". The aim is to solve the classic process method where the equipment stroke is less than the workpiece length.

[0040] Segmented pressure application: The problem of straightening a long workpiece is broken down into the problem of straightening multiple short segments.

[0041] Overlap correction (200mm): This is crucial for ensuring the continuity of correction quality. Without overlap, a "mutation point" will form at the junction of two correction sections—a region that suddenly becomes undeformed, causing undulations or localized unevenness throughout the flange. A 200mm overlap provides a smooth transition, resulting in a flat and continuous flange after correction. This overlap length is usually determined empirically and must be sufficient to cover the "elastic influence zone" of the previous correction.

[0042] Step 4: After the upper flange plate 5 is straightened, the straightening pressure head 2 is lifted to lift the H-beam out and turn it 180°.

[0043] Workpiece flipping: After straightening the upper flange, rotate the H-beam 180°. Purpose: During H-beam welding, the angular deformation of the upper and lower flanges is usually symmetrical (both tilting upwards or downwards). Therefore, the same straightening operation must be performed on the other flange to restore the entire H-beam to a straight state.

[0044] Step 5: Insert the long H-beam 1 or the short H-beam 4 into the straightening mold 3, start the hydraulic press, and the straightening pressure head 2 descends to contact the upper surface of the lower flange plate 7 and apply pressure.

[0045] Correct the other flange plate. Procedure: Repeat steps two and three to correct the lower flange plate 7.

[0046] Step 6: After the correction is completed, use a crane to lift the component out.

[0047] Material preparation and operation: After straightening, lift the H-beams away from the mold. Follow-up: Inspection is usually required, such as using a ruler, level, or laser level to check the flatness and overall straightness of the flanges to confirm whether they meet quality standards.

[0048] The straightening process utilizes a three-point bending reverse bending method. Two lower support points are provided by the straightening grooves on the straightening mold, supporting the lower flange of the H-beam. One upper force application point is provided by the vertical pressure plate of the straightening head, applying downward pressure to the upper flange of the H-beam. When the pressure exceeds the yield strength of the steel, the metal near the force application point undergoes plastic deformation, thus "flattening" the original angular deformation in the reverse, achieving the straightening purpose.

[0049] In summary, this method for correcting the welding angular deformation of H-beam flanges, when applied to welded H-beam components, results in angular deformation of the flanges after welding. Using an H-beam flange straightening machine or flame straightening may cause some damage to the base material. By employing the invented H-beam flange straightening method and apparatus, the post-weld angular deformation of the H-beam flanges can be corrected, avoiding damage to the base material and the need for subsequent repairs, thus significantly improving straightening efficiency.

[0050] The above description is only a specific embodiment of the present invention, but the structural features of the present invention are not limited thereto. Any changes or modifications made by those skilled in the art within the scope of the present invention are covered by the patent scope of the present invention.

Claims

1. A method for correcting the welding angle deformation of H-beam flange plates, wherein the H-beam includes a long H-beam (1) and a short H-beam (4), wherein the long H-beam (1) and the short H-beam (2) are composed of three plates: an upper flange plate (5), a web plate (6), and a lower flange plate (7), characterized in that: The long H-beam (1) and short H-beam (4) are straightened using a straightening pressure head (2) and a straightening mold (3); the straightening method includes the following steps: Step 1: Place the straightening mold (3) under the hydraulic press, install the straightening head (2) on the hydraulic press, and position the straightening head (2) directly above the straightening mold (3). The center line of the straightening head (2) and the center line of the groove on the upper cover plate of the straightening mold (3) are on the same plane. Step 2: Insert the long H-beam (1) or short H-beam (4) into the straightening mold (3), with the end of the H-beam flush with the end of the straightening mold (3); Step 3: Start the hydraulic press, lower the straightening head (2) to contact the upper surface of the upper flange (5) and apply a clamping force; Step 4: After the upper flange plate (5) is straightened, the straightening pressure head (2) is lifted to lift the H-beam out and turn it 180°. Step 5: Insert the long H-beam (1) or short H-beam (4) into the straightening mold (3), start the hydraulic press, and the straightening pressure head (2) descends to contact the upper surface of the lower flange plate (7) and apply pressure; Step 6: After the correction is completed, use a crane to lift the component out.

2. The method for correcting welding angle deformation of H-beam flanges according to claim 1, characterized in that: When straightening the long H-beam (1), it is inserted and hoisted in through the end hole and slot of the straightening mold (3) on one side. The end of the long H-beam (1) is flush with the end of the straightening mold. The other end of the long H-beam (1) is lifted by the crane hook and kept horizontal.

3. The method for correcting welding angle deformation of H-beam flanges according to claim 2, characterized in that: During the straightening process, the long H-beam (1) is lifted by a crane and moved a certain distance to the end of the straightening mold (3), while the other end is still lifted by the crane hook to keep it horizontal.

4. The method for correcting welding angle deformation of H-beam flanges according to claim 3, characterized in that: To ensure the corrective effect, the corrected length is not completely removed from the correction area; approximately 200mm is left for further correction.

5. The method for correcting welding angle deformation of H-beam flanges according to claim 1, characterized in that: The straightening mold (3) includes a base plate (12), and the base plate (12) has end plates (8) at both ends. Several stiffening plates (10) are provided between the two end plates (8). The stiffening plates (10) and the end plates (8) are provided with straightening grooves (11) for H-beams to pass through and be limited.

6. The method for correcting welding angle deformation of H-beam flanges according to claim 5, characterized in that: The bottom plate (12) is provided with side plates (13) that are welded and fixed to the side of the end plate (8) at both ends. The stiffening plate (10) and the upper part of the end plate (8) are provided with a pair of cover plates (9) with a gap distribution. The gap between the two cover plates (9) is connected to the straightening groove (11).

7. The method for correcting welding angle deformation of H-beam flanges according to claim 1, characterized in that: The corrective pressure head (2) is composed of a horizontal pressure plate (14) and a vertical pressure plate (15). The corrective pressure head (2) has a "T" shaped structure. The end of the vertical pressure plate (15) is processed into an arc shape.

Images