Precision straightening device for thin-walled seamless steel pipes

Abstract

The application discloses a kind of thin-walled seamless steel tube precision straightening device, including rack, the upper portion of the rack of straightening assembly discharge end is slidably provided with crossbeam, the upper portion of crossbeam is provided with movable support, rotatable joint is installed on movable support, the inlet end of rotatable joint is connected with the liquid filling mechanism for filling liquid medium in thin-walled seamless steel tube, and liquid guide pipe is fixedly connected with rotatable joint in screw thread, the outside of plug rod and liquid guide pipe is all equipped with top spring, the side of top spring is provided with annular push piece, the side of annular push piece is provided with the elastic collar matched with thin-walled seamless steel tube, and the outside of liquid guide pipe inserted into the end of thin-walled seamless steel tube is equipped with expansion plug.The application can be injected into liquid medium to the thin-walled seamless steel tube to be straightened, so as to increase the structural strength of thin-walled seamless steel tube, avoid the concave phenomenon when roller is straightened to thin-walled seamless steel tube, and simultaneously can be tested to the strength of thin-walled seamless steel tube by high-pressure liquid medium.

Description

Technical Field

[0001] This invention relates to the field of seamless steel pipe production technology, specifically to a precision straightening device for thin-walled seamless steel pipes. Background Technology

[0002] Seamless steel pipes are made by piercing a whole round steel bar. They are steel pipes without weld seams on the surface. Depending on the application, there are thick-walled seamless steel pipes and thin-walled seamless steel pipes. In order to eliminate the longitudinal bending and roundness error of seamless steel pipes after rolling, it is generally necessary to straighten the seamless steel pipes. Among them, the six-roll skew roll straightener is commonly used in the straightening process.

[0003] The existing six-roll skew roll straightener has six straightening rolls arranged symmetrically in three pairs, all of which are active rolls. The straightener frame consists of upper and lower parts. The upper frame is equipped with three sets of height adjustment, balancing, and locking devices for the upper rolls, each controlling one roll independently. The lower frame is equipped with one set of height adjustment, balancing, and locking devices for the middle and lower rolls. The upper and lower frames are connected as a single unit by eight columns, which are fixed to the lower frame. The frame and columns are prestressed during installation. Six angle adjustment mechanisms are installed on the columns, each adjusting one roll independently. The hydraulic locking device eliminates any adjustment gaps in the straightening rolls and ensures that the straightening rolls are in the same position during operation. The straightening rollers are driven in groups. The three upper rollers and three lower rollers are driven by one motor, one reducer and three universal joints. However, when this type of straightening device straightens thin-walled seamless steel pipes, the contact stress between the rollers and the steel pipe is prone to exceed the structural strength of the thin-walled seamless steel pipe, resulting in depressions on the surface of the thin-walled seamless steel pipe (commonly known as cross-sectional distortion), which reduces the pass rate of thin-walled seamless steel pipe production. Summary of the Invention

[0004] The purpose of this invention is to provide a precision straightening device for thin-walled seamless steel pipes to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a precision straightening device for thin-walled seamless steel pipes, comprising a frame and a straightening assembly. A crossbeam is slidably arranged on the upper part of the frame at the discharge end of the straightening assembly. A movable support is arranged on the upper part of the crossbeam. A rotary joint is installed on the movable support. The inlet end of the rotary joint is connected to a filling mechanism for filling the thin-walled seamless steel pipe with liquid medium. Insert rods and liquid guide pipes are respectively inserted into both ends of the thin-walled seamless steel pipe, and the liquid guide pipes are threadedly connected and fixed to the rotary joints. A tightening spring is sleeved on the outer side of both the insert rods and the liquid guide pipes. An annular push plate is arranged on one side of the tightening springs, and an elastic retaining ring matching the thin-walled seamless steel pipe is arranged on one side of the annular push plate. An expansion plug is sleeved on the outer side of the end of the liquid guide pipe inserted into the thin-walled seamless steel pipe.

[0006] Preferably, the expansion plug includes a guide sleeve, a support plate, an arc-shaped support strip, an arc-shaped connecting plate, a pin, a rubber sealing sleeve, and a push sleeve. The outer sides of the liquid guide tube and the insertion rod are respectively fitted with guide sleeves. The outer sides of the guide sleeves are uniformly hinged with support plates, and the other end of the support plate is hinged with an arc-shaped support strip that matches the inner wall of the thin-walled seamless steel pipe. Pins are provided through one side of both ends of the arc-shaped support strip, and the arc-shaped support strip has guide grooves that match the pins. Arc-shaped connecting plates are uniformly arranged between two adjacent pins, and the arc-shaped support strip has storage slots that match the arc-shaped connecting plates. A flared rubber sealing sleeve is fitted on the outer side of several arc-shaped support strips. The contracted end of the rubber sealing sleeve is connected to a push sleeve, and the push sleeve is threadedly connected to the corresponding insertion rod and liquid guide tube.

[0007] Preferably, the rubber sealing sleeve includes a rubber sleeve, an arc-shaped rubber strip, and a telescopic rubber strip. The outer side of the push sleeve is provided with a rubber sleeve, and the outer side of the rubber sleeve is uniformly provided with arc-shaped rubber strips. The arc-shaped rubber strips are glued and fixed to the arc-shaped support strips. A corrugated telescopic rubber strip is connected between two adjacent arc-shaped rubber strips, and the telescopic rubber strip is glued and fixed to the rubber sleeve.

[0008] Preferably, the liquid filling mechanism includes a liquid collecting hopper, a liquid storage tank, a pump body, a pressure control valve, and a filter screen. The frame is provided with a liquid collecting hopper for collecting liquid media, and a filter screen is provided inside the liquid collecting hopper. A liquid storage tank connected to the liquid collecting hopper is provided on one side of the frame, and a pump body is provided on one side of the liquid storage tank. The outlet end of the pump body is connected to the inlet end pipe of the rotary joint, and a pressure control valve for controlling the internal pressure of the injected liquid media is provided on the pipe.

[0009] Preferably, the movable support includes a slider, a guide sleeve, an elastic support, an extension column, a mounting sleeve, and a spherical mounting seat. The upper part of the crossbeam is slidably provided with a slider, the upper end of the slider is provided with a guide sleeve, the guide sleeve is provided with an elastic support, the upper end of the elastic support is inserted with an extension column, the upper end of the extension column is provided with a mounting sleeve, and the mounting sleeve is provided with a spherical mounting seat for mounting a rotary joint.

[0010] Preferably, the elastic retaining ring consists of an elastic retaining ring, an elastic support strip, and a claw. An elastic retaining ring with a V-shaped cross-section is provided on one side of the annular push plate, and the diameter of the elastic retaining ring near the annular push plate is larger than the inner diameter of the thin-walled seamless steel pipe. An elastic support strip is uniformly connected to the outer side of the elastic retaining ring away from the annular push plate, and the elastic support strip is at an angle of 30 to 40 degrees to the side of the elastic retaining ring it is connected to. A claw is connected to the outer end of the elastic support strip, and the outer side of the claw is in contact with the inner wall of the thin-walled seamless steel pipe.

[0011] Compared with the prior art, the present invention provides a precision straightening device for thin-walled seamless steel pipes, which has the following beneficial effects: The present invention makes the thin-walled seamless steel pipe into a sealed chamber by inserting expansion plugs at both ends of the thin-walled seamless steel pipe to be straightened, and injects high-pressure liquid medium into the sealed chamber through a liquid filling mechanism, thereby increasing the structural strength of the thin-walled seamless steel pipe, avoiding the phenomenon of indentation when the rollers straighten the thin-walled seamless steel pipe, and enabling strength testing of the thin-walled seamless steel pipe through high-pressure liquid medium. Attached Figure Description

[0012] Figure 1 This is the front view of the present invention;

[0013] Figure 2 This is a front sectional view of the present invention;

[0014] Figure 3 for Figure 1 Schematic diagram of the cross-sectional structure at point A in the middle;

[0015] Figure 4 for Figure 1 Schematic diagram of the cross-sectional structure at point B in the middle;

[0016] Figure 5 for Figure 2 Enlarged structural diagram of section C;

[0017] Figure 6 This is a side view of the rubber sealing sleeve in this invention;

[0018] Figure 7 This is a side view of the elastic retaining ring in this invention.

[0019] In the diagram: 1. Frame; 2. Straightening assembly; 3. Crossbeam; 4. Movable support; 40. Slider; 41. Guide sleeve; 42. Elastic support; 43. Extension column; 44. Mounting sleeve; 45. Spherical mounting seat; 5. Rotary joint; 6. Filling mechanism; 60. Liquid collecting hopper; 61. Liquid storage tank; 62. Pump body; 63. Pressure control valve; 64. Filter screen; 7. Liquid guide pipe; 8. Expansion plug; 80. Guide sleeve; 81. Support plate; 82. Arc-shaped support bar; 83. Arc-shaped connecting plate; 84. Pin; 85. Rubber sealing sleeve; 850. Rubber sleeve; 851. Arc-shaped rubber strip; 852. Telescopic rubber strip; 86. Push sleeve; 9. Tightening spring; 10. Annular push plate; 11. Elastic retaining ring; 110. Elastic retaining ring; 111. Elastic support bar; 112. Claw; 12. Insert rod. Detailed Implementation

[0020] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0021] Please see Figure 1-7This invention provides an embodiment of a precision straightening device for thin-walled seamless steel pipes: A precision straightening device for thin-walled seamless steel pipes includes a frame 1 and a straightening assembly 2. A crossbeam 3 is slidably mounted on the upper part of the frame 1 at the discharge end of the straightening assembly 2. A slider 40 is slidably mounted on the upper part of the crossbeam 3. A guide sleeve 41 is mounted on the upper end of the slider 40. An elastic support 42 is installed inside the guide sleeve 41. An extension column 43 is inserted into the upper end of the elastic support 42. An installation sleeve 44 is installed on the upper end of the extension column 43. A spherical mounting seat 45 for mounting a rotary joint 5 is installed inside the installation sleeve 44. The slider 40 and the crossbeam 3 are slidably connected, allowing the guide sleeve 41 at the upper end of the slider 40 to move freely along the crossbeam 3. Simultaneously, the extension column 4... The guide sliding connection between the extension column 43 and the guide sleeve 41 allows the extension column 43 to slide freely up and down. The movable connection between the spherical mounting base 45 and the mounting sleeve 44 allows the rotary joint 5 inside the spherical mounting base 45 to rotate flexibly, thus allowing the liquid guide tube 7 to freely change position with the thin-walled seamless steel pipe, preventing the liquid guide tube 7 from falling out of the thin-walled seamless steel pipe. Insert rods 12 and liquid guide tubes 7 are respectively inserted at both ends of the thin-walled seamless steel pipe, and the liquid guide tube 7 is threadedly connected and fixed to the rotary joint 5. A tightening spring 9 is fitted on the outside of both the insert rod 12 and the liquid guide tube 7. An annular push plate 10 is provided on one side of the tightening spring 9, and an elastic element matching the thin-walled seamless steel pipe is provided on one side of the annular push plate 10. The retaining ring 11, pushed by the tightening spring 9, pushes the annular push plate 10, which in turn pushes the elastic retaining ring 11, thus fixing the liquid guide tube 7 and the insertion rod 12 to the same central axis as the corresponding thin-walled seamless steel pipe ends. Simultaneously, guide sleeves 80 are fitted on the outer sides of the liquid guide tube 7 and the insertion rod 12, with support plates 81 evenly hinged to the outer sides of the guide sleeves 80. The other end of the support plate 81 is hinged to an arc-shaped support strip 82 that matches the inner wall of the thin-walled seamless steel pipe. Pins 84 are threaded through one side of both ends of the arc-shaped support strip 82, and the arc-shaped support strip 82 has guide grooves matching the pins 84. Arc-shaped connecting plates 83 are evenly arranged between adjacent pins 84, and the arc-shaped support strip 82 has guide grooves matching the arc shape. The connecting plate 83 has a matching storage slot. Several arc-shaped support bars 82 are fitted with flared rubber sealing sleeves 85 on their outer sides. The constricted end of the rubber sealing sleeve 85 is connected to a push sleeve 86, and the push sleeve 86 is threadedly connected to the corresponding insertion rod 12 and liquid guide tube 7. Through the threaded connection between the liquid guide tube 7, the insertion rod 12 and the push sleeve 86, the push sleeve 86 pushes the guide slide sleeve 80, which in turn drives the support plate 81 to move synchronously. At the same time, through the limitation of the arc-shaped connecting plate 83 and the pin 84, the support plate 81 can push the arc-shaped support bars 82 to expand outward, so that the rubber sealing sleeve 85 outside the arc-shaped support bar 82 can fit tightly against the inner wall of the thin-walled seamless steel pipe, thereby sealing the thin-walled seamless steel pipe.

[0022] A rotary joint 5 is installed on the movable support 4, and a liquid collection hopper 60 for collecting liquid media is set on the frame 1. A filter screen 64 is installed inside the liquid collection hopper 60. A storage tank 61 connected to the liquid collection hopper 60 is set on one side of the frame 1. A pump body 62 is set on one side of the storage tank 61. The outlet end of the pump body 62 is connected to the inlet end pipe of the rotary joint 5. A pressure control valve 63 for controlling the internal pressure of the injected liquid media is set on the pipeline. The liquid media in the storage tank 61 is drawn out by the pump body 62, and the internal pressure of the liquid media injected into the thin-walled seamless steel pipe is controlled by the pressure control valve 63 to avoid damage to the thin-walled seamless steel due to excessive internal pressure of the liquid media. At the same time, the liquid media flowing out of the thin-walled seamless steel pipe is collected, recycled and reused by the liquid collection hopper 60.

[0023] In this implementation, such as Figure 6 As shown, the rubber sealing sleeve 85 includes a rubber sleeve 850, an arc-shaped rubber strip 851, and a telescopic rubber strip 852. The rubber sleeve 850 is provided on the outer side of the push sleeve 86. Arc-shaped rubber strips 851 are evenly provided on the outer side of the rubber sleeve 850, and the arc-shaped rubber strips 851 are glued to the arc-shaped support strip 82. A corrugated telescopic rubber strip 852 is connected between two adjacent arc-shaped rubber strips 851, and the telescopic rubber strip 852 is glued to the rubber sleeve 850. The telescopic rubber strip 852 makes it easy for the rubber sealing sleeve 85 to automatically shrink, thereby facilitating the insertion of the expansion plug 8 into the thin-walled seamless steel pipe.

[0024] In this implementation, such as Figure 7 As shown, the elastic retaining ring 11 consists of an elastic retaining ring 110, an elastic support bar 111, and a retaining claw 112. An elastic retaining ring 110 with a V-shaped cross-section is provided on one side of the annular push plate 10, and the diameter of the elastic retaining ring 110 near the annular push plate 10 is larger than the inner diameter of the thin-walled seamless steel pipe. The elastic support bar 111 is evenly connected to the outer side of the elastic retaining ring 110 away from the annular push plate 10, and the elastic support bar 111 is at a 30-40 degree angle to the side of the elastic retaining ring 110 it is connected to. The outer end of the elastic support bar 111 is connected to a retaining claw 112, and the outer side of the retaining claw 112 is in contact with the inner wall of the thin-walled seamless steel pipe. By the deformation of the elastic retaining ring 110 and the elastic support bar 111, the retaining claw 112 is pushed, so that the retaining claw 112 can be tightly fitted with the inner wall of the thin-walled seamless steel pipe, thereby allowing the elastic retaining ring 11 to be locked inside the thin-walled seamless steel pipe.

[0025] Working principle: During operation, the liquid guide tube 7 and the insertion rod 12 are inserted into the first and last ends of the thin-walled seamless steel pipe to be straightened, respectively. The tightening spring 9 pushes the annular push plate 10, which in turn pushes the elastic retaining ring 11, thus fixing the liquid guide tube 7 and the insertion rod 12 and aligning them with the corresponding thin-walled seamless steel pipe ends on the same central axis. Simultaneously, the liquid guide tube 7 and the insertion rod 12 are screwed on. Utilizing the threaded connection between the liquid guide tube 7 and the insertion rod 12 and the push sleeve 86, the push sleeve 86 pushes the guide sleeve 80, causing the guide sleeve 80 to move synchronously with the support plate 81. Simultaneously, the arc-shaped connecting plate 83 and the pin 84 limit the movement of the support plate 81, allowing the arc-shaped support bar 82 to expand outwards. This allows the rubber sealing sleeve 85 outside the arc-shaped support bar 82 to fit tightly against the inner wall of the thin-walled seamless steel pipe, thereby sealing the pipe. The pump body 62 then pumps the liquid into the storage tank. The liquid medium in 61 is extracted, and the internal pressure of the liquid medium injected into the thin-walled seamless steel pipe is controlled by the pressure control valve 63 to avoid damage to the thin-walled seamless steel pipe due to excessive internal pressure of the liquid medium. At the same time, the sliding connection between the slider 40 and the crossbeam 3 allows the guide sleeve 41 at the upper end of the slider 40 to move freely along the crossbeam 3. The guide sliding connection between the extension column 43 and the guide sleeve 41 allows the extension column 43 to slide freely up and down. At the same time, the movable connection between the spherical mounting base 45 and the mounting sleeve 44 allows the rotary joint 5 in the spherical mounting base 45 to rotate flexibly, so that the liquid guide tube 7 can change freely with the position of the thin-walled seamless steel pipe, preventing the liquid guide tube 7 from falling out of the thin-walled seamless steel pipe during the rotation straightening process. At the same time, the thin-walled seamless steel pipe is subjected to strength testing using high-pressure liquid medium.

[0026] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0027] In the description of this invention, unless otherwise stated, "a plurality of" means two or more; the terms "upper," "lower," "left," "right," "inner," "outer," "front end," "rear end," "head," "tail," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first," "second," "third," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0028] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

Claims

1. A device for precision straightening of thin-walled seamless steel pipes, comprising a frame (1) and a straightening assembly (2), characterized in that: The upper part of the rack (1) of the straightening assembly (2) is slidably provided with a crossbeam (3), the upper part of the crossbeam (3) is provided with a movable support (4), a rotary joint (5) is installed on the movable support (4), the inlet end of the rotary joint (5) is connected with a liquid filling mechanism (6) for filling liquid medium into the thin-walled seamless steel pipe, the two ends of the thin-walled seamless steel pipe are respectively inserted with a plug rod (12) and a liquid guide pipe (7), and the liquid guide pipe (7) is threadedly connected with the rotary joint (5) and fixed, the outer sides of the plug rod (12) and the liquid guide pipe (7) are respectively sleeved with a jacking spring (9), one side of the jacking spring (9) is provided with an annular push piece (10), one side of the annular push piece (10) is provided with an elastic clasp (11) matched with the thin-walled seamless steel pipe, and the outer side of the liquid guide pipe (7) inserted into the end of the thin-walled seamless steel pipe is sleeved with an expansion plug (8). The expansion plug (8) comprises a guide sleeve (80), a supporting plate (81), an arc-shaped supporting strip (82), an arc-shaped connecting plate (83), a pin shaft (84), a rubber sealing sleeve (85) and a push sleeve (86), the outer sides of the liquid guide pipe (7) and the plug rod (12) are respectively sleeved with the guide sleeve (80), the outer sides of the guide sleeves (80) are uniformly hinged with the supporting plates (81), the other ends of the supporting plates (81) are hinged with the arc-shaped supporting strips (82) matched with the inner walls of the thin-walled seamless steel pipes, the two ends of one side of the arc-shaped supporting strips (82) are respectively provided with the pin shafts (84), the arc-shaped supporting strips (82) are provided with guide sliding grooves matched with the pin shafts (84), the adjacent two pin shafts (84) are uniformly provided with the arc-shaped connecting plates (83), the arc-shaped supporting strips (82) are provided with receiving insertion grooves matched with the arc-shaped connecting plates (83), the outer sides of the arc-shaped supporting strips (82) are sleeved with the rubber sealing sleeves (85) in the shape of a horn, the contraction ends of the rubber sealing sleeves (85) are connected with the push sleeves (86), and the push sleeves (86) are threadedly connected with the corresponding plug rods (12) and liquid guide pipes (7). The elastic clasp (11) is composed of an elastic retaining ring (110), an elastic supporting strip (111) and a clamping jaw (112), one side of the annular push piece (10) is provided with the elastic retaining ring (110) in the shape of a V-shaped section, the diameter of one side of the elastic retaining ring (110) close to the annular push piece (10) is greater than the inner diameter of the thin-walled seamless steel pipe, the outer sides of the elastic retaining rings (110) away from the annular push piece (10) are uniformly connected with the elastic supporting strips (111), the side edges of the elastic supporting strips (111) connected with the elastic retaining rings (110) are at an angle of 30-40 degrees, and the outer ends of the elastic supporting strips (111) are connected with the clamping jaws (112), and the outer sides of the clamping jaws (112) are attached to the inner walls of the thin-walled seamless steel pipes.

2. The thin-walled seamless steel tube precision straightening device according to claim 1, characterized in that: The rubber sealing sleeve (85) comprises a rubber sleeve (850), arc-shaped rubber strips (851) and elastic rubber strips (852), the outer side of the push sleeve (86) is provided with the rubber sleeve (850), the outer side of the rubber sleeve (850) is uniformly provided with the arc-shaped rubber strips (851), the arc-shaped rubber strips (851) are adhesively fixed with the arc-shaped supporting strips (82), the adjacent two arc-shaped rubber strips (851) are connected with the elastic rubber strips (852) in a corrugated shape, and the elastic rubber strips (852) are adhesively fixed with the rubber sleeve (850).

3. The device for precision straightening of thin-walled seamless steel pipes according to claim 2, characterized in that: The liquid filling mechanism (6) comprises a liquid collecting hopper (60), a liquid storage tank (61), a pump body (62), a pressure control valve (63) and a filter screen (64), the rack (1) is provided with the liquid collecting hopper (60) for collecting liquid medium, the filter screen (64) is arranged in the liquid collecting hopper (60), one side of the rack (1) is provided with the liquid storage tank (61) communicated with the liquid collecting hopper (60), one side of the liquid storage tank (61) is provided with the pump body (62), the liquid outlet end of the pump body (62) is connected with the inlet end pipe of the rotary joint (5), and the pressure control valve (63) for controlling the pressure of the injected liquid medium is arranged on the pipeline.

4. The device for precision straightening of thin-walled seamless steel pipes according to claim 3, characterized in that: The movable support (4) comprises a sliding block (40), a guide sleeve (41), an elastic support (42), an extension column (43), a mounting sleeve (44) and a spherical mounting seat (45), the upper portion of the cross beam (3) is slidably provided with the sliding block (40), the upper end of the sliding block (40) is provided with the guide sleeve (41), the guide sleeve (41) is internally provided with the elastic support (42), the upper end of the elastic support (42) is inserted with the extension column (43), the upper end of the extension column (43) is provided with the mounting sleeve (44), and the mounting sleeve (44) is internally provided with the spherical mounting seat for mounting the rotary joint (5).

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