A mandrel restraining device

Abstract

The present invention relates to the technical field of steel pipe rolling, and relates to a mandrel limiting device. Two sections of stepped shafts are provided at the tail of the mandrel, namely a first stepped shaft and a second stepped shaft; the rod threading device includes a rod threading device body and a rod threading push head. One end of the rod threading device body close to the mandrel is in contact connection with the tail end of the mandrel. The rod threading push head is hinged on the rod threading device body and is in a horizontal state without external force, and is clamped on the first stepped shaft to realize the detachable connection between the rod threading device and the mandrel; the limiting clamping device includes a limiting clamping head and a limiting driving device for driving the limiting clamping head. The front end of the mandrel passes through the limiting clamping head. The limiting clamping head clamps and fixes the second stepped shaft at the tail of the mandrel and is in contact connection with the two side steps of the second stepped shaft to realize the limiting rolling of the mandrel. The present invention solves the problem of the long rolling cycle of steel pipes in the prior art through two-stage online rod threading rolling, and improves the production efficiency.

Description

Technical Field

[0001] The present invention belongs to the technical field of steel pipe rolling and relates to a mandrel limiting device. Background Art

[0002] In the limit rolling of seamless steel pipes, the operation of the mandrel is controlled throughout the rolling process to make it run at a set speed. There are two modes: online mandrel threading and offline pre-threading during production.

[0003] During offline pre-threading, the mandrel sprayed with graphite is inserted into the billet stopped on the pre-threading line by the pre-threading device. After the mandrel is inserted, the billet is laterally shifted to the main rolling line by the transfer device for limit rolling. However, the temperature drop of the billet is relatively large. Therefore, online mandrel threading is usually adopted for production. During online mandrel threading, the billet is directly laterally shifted to the main rolling line by the transfer device. At the same time, the transfer device sends the lubricated mandrel into the rolling line, and the tail of the mandrel just falls into the mandrel clamping mechanism at the front end of the limiting device (limiting rack). After the mandrel is in place, the limiting rack is driven by a gear to drive the mandrel to advance for mandrel threading and rolling. After rolling is completed, the limiting rack is retracted to the waiting position and the used mandrel is unloaded, and then the next limit rolling cycle is carried out. Therefore, in the existing online mandrel threading, the auxiliary working time for mandrel threading and mandrel limit clamping is relatively long, resulting in a relatively long rolling cycle of the steel pipe and low production efficiency.

[0004] Therefore, it is necessary to propose a new mandrel limiting device to solve the above problems. Summary of the Invention

[0005] In view of this, the purpose of the present invention is to provide a double-step mandrel limiting device, which adopts two-stage online mandrel threading rolling to solve the problem of the relatively long rolling cycle of steel pipes in the prior art and improve production efficiency.

[0006] To achieve the above purpose, the present invention provides the following technical solutions:

[0007] A double-step mandrel limiting device includes a rolling conveyor roller path arranged on the rolling center line. One end of the rolling conveyor roller path is docked with a rolling mill, and a mandrel threading device is arranged at the other end. A limiting clamping device is arranged between the mandrel threading device and the rolling mill. The mandrel is clamped and fixed by the limiting clamping device for limit rolling. Two stepped shafts are arranged at the tail of the mandrel, namely a first stepped shaft and a second stepped shaft. The outer diameter of the mandrel is consistent, and the outer diameters of the two stepped shafts at the tail of the mandrel are smaller than the outer diameter of the mandrel, so that the mandrel can pass through the rolling conveyor roller path;

[0008] The rod threading device includes a rod threading device body and a rod threading push head. One end of the rod threading device body close to the mandrel abuts and connects with the tail end of the mandrel. The rod threading push head is rotationally connected to the rod threading device body through a hinge shaft, and is in a horizontal state without external force, and is clamped on the first stepped shaft to achieve the detachable connection between the rod threading device and the mandrel;

[0009] The limiting and clamping device includes a limiting and clamping head and a limiting driving device for driving the limiting and clamping head. The front end of the mandrel passes through the limiting and clamping head. The limiting and clamping head clamps and fixes the second stepped shaft located at the tail of the mandrel, and abuts and connects with the two side steps of the second stepped shaft to achieve the limiting rolling of the mandrel.

[0010] Further, both ends of the hinge shaft are provided with a first driving device for driving the rotation of the hinge shaft to achieve the rotation of the rod threading push head, so as to achieve the detachable connection between the rod threading push head and the mandrel.

[0011] Further, the rod threading device body includes a first driving rack and a first gear set for driving the first driving rack. The rod threading push head is hinged on the first driving rack.

[0012] Further, a guiding inclined surface is provided between the tail end of the mandrel and the first stepped shaft to facilitate the clamping of the rod threading push head and the first stepped shaft.

[0013] Further, the limiting and clamping head includes a clamping head body and a fixed limiting frame for installing the clamping head body. The clamping head body opens or closes under the action of a second driving device to achieve the clamping or blanking of the mandrel. The fixed limiting frame is connected to the limiting driving device to achieve the limiting rolling of the mandrel.

[0014] Further, the limiting driving device includes a second driving rack and a second gear set for driving the second driving rack. The limiting and clamping head is fixedly connected to the second driving rack.

[0015] Further, the limiting driving device further includes a fixed frame for installing the second rack, a roller set installed on the second driving rack, and a guiding wheel connected to the roller set. The roller set is located on the adjacent two sides of the side of the second driving rack meshing with the second gear set, and is slidably connected to the fixed frame.

[0016] Further, a running bed for slidably connecting with the roller set and the guiding wheel is provided on the fixed frame to achieve the slidable connection between the second driving rack and the fixed frame.

[0017] The beneficial effects of the present invention are as follows:

[0018] In the present invention, the rod threading device and the limit clamping device are arranged distributively. The rod threading device is arranged at one end of the rolling conveying roller path far from the rolling mill, and the limit clamping device is arranged between the rod threading device and the rolling mill. Moreover, two stepped shafts are provided at the tail of the mandrel to form a double-stepped mandrel, so as to facilitate the detachable connection between the rod threading device and the limit clamping device and the mandrel. During the rolling process, first, the rod threading device threads the mandrel into the tube blank at a set speed and runs to the position where the limit clamping device is located. The limit clamping device is engaged and coordinated with the rod threading device. After the front ends of the mandrel and the tube blank pass through the limit clamping head, the limit clamping head clamps and fixes the mandrel by clamping the second stepped shaft. The rod threading push head rotates and leaves the first stepped shaft of the mandrel, and the rod threading device is separated from the mandrel. The mandrel is subjected to limit rolling under the action of the limit clamping device, thereby realizing two-stage online rod threading rolling. During the limit rolling process, the rod threading device can return to the waiting position, without occupying the rolling cycle time. After the rolling is completed, the limit clamping device clamps the mandrel and retracts at high speed. After the mandrel exits the rolling mill, the limit clamping head opens, and the transfer device can move the mandrel out of the rolling center line and enter the next limit rolling cycle, shortening the rolling cycle and improving the production efficiency.

[0019] Other advantages, objectives, and features of the present invention will be described to some extent in the subsequent specification, and to some extent, will be obvious to those skilled in the art based on the study of the following text, or can be taught from the practice of the present invention. The objectives and other advantages of the present invention can be realized and obtained through the following specification. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be described in detail preferably with reference to the accompanying drawings, where:

[0021] Figure 1 is a schematic structural diagram of a double-stepped mandrel limit device in an embodiment;

[0022] Figure 2 is a sectional structural diagram of the limit clamping device in an embodiment;

[0023] Figure 3 is a diagram of the rod threading working state of a double-stepped mandrel limit device in an embodiment

[0024] Figure 4 is a diagram of the working state of the connection between the rod threading device and the limit clamping device in an embodiment.

[0025] Reference numerals: mandrel 1, rod threading device 2, dummy block clamping device 3, tube 4, first stepped shaft 101, second stepped shaft 102, guiding inclined surface 103, rod threading device body 201, rod threading push head 202, center of gravity of rod threading push head 2021, hinge shaft 203, clamping head body 301, fixed dummy block frame 302, second driving rack 303, roller set 304, side guiding wheel 305, running bed 306, fixed frame 307, second gear set 308. Detailed implementation manners

[0026] The following uses specific specific examples to illustrate the implementation manners of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific implementation manners. Various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the drawings provided in the following embodiments only schematically illustrate the basic concept of the present invention. Without conflict, the following embodiments and the features in the embodiments can be combined with each other.

[0027] Among them, the drawings are only for illustrative purposes, showing only schematic diagrams, not physical diagrams, and should not be construed as a limitation on the present invention; in order to better illustrate the embodiments of the present invention, some components in the drawings will be omitted, enlarged or reduced, and do not represent the dimensions of actual products; for those skilled in the art, it is understandable that some well-known structures and their descriptions in the drawings may be omitted.

[0028] In the drawings of the embodiments of the present invention, the same or similar reference numerals correspond to the same or similar components; in the description of the present invention, it should be understood that if there are terms such as "upper", "lower", "left", "right", "front", "rear", etc. indicating the orientation or positional relationship, they are based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, the terms describing the positional relationship in the drawings are only for illustrative purposes and should not be construed as a limitation on the present invention. For those of ordinary skill in the art, the specific meanings of the above terms can be understood according to specific circumstances.

[0029] In this embodiment, the tail end and the front end are referenced by the distance from the rolling mill. The end close to the rolling mill is the front end, and the end far from the rolling mill is the tail end.

[0030] Please refer to Figures 1 to 3, is a mandrel limiting device, comprising a rolling conveyor roller table arranged on the rolling center line, one end of the rolling conveyor roller table is connected to the rolling mill, and the other end is provided with a rod insertion device 2, a limiting clamping device 3 is provided between the rod insertion device 2 and the rolling mill, and the mandrel 1 is clamped and fixed by the limiting clamping device 3 to perform limited rolling, and the tail of the mandrel 1 is provided with two stepped shafts, namely the first stepped shaft 101 and the second stepped shaft 102; the rod insertion device 2 comprises a rod insertion device body 201 and a rod insertion pusher 202, and the end of the rod insertion device body 201 close to the mandrel 1 is in contact with the tail end of the mandrel 1, and the rod insertion pusher 202 is hinged on the rod insertion device body 201, and the center of gravity of the rod insertion pusher 2 021 is located at one end of the rod pushing head 202 close to the core rod 1, and is in a horizontal state without the action of external force, and is clamped on the first stepped shaft 101 to realize the detachable connection between the rod pushing device 2 and the core rod 1, and a guide inclined surface 103 is provided between the tail end of the core rod 1 and the first stepped shaft 101 to facilitate the clamping of the rod pushing head 202 and the first stepped shaft 101; the limiting clamping device 3 includes a limiting clamping head and a limiting driving device for driving the limiting clamping head, the front end of the core rod 1 passes through the limiting clamping head, the limiting clamping head clamps and fixes the second stepped shaft 102 located at the tail of the core rod 1, and is in contact with the steps on both sides of the second stepped shaft 102 to realize the limited rolling of the core rod 1.

[0031] In this embodiment, the outer diameter of the mandrel 1 is consistent, and the outer diameter of the two stepped shafts at the tail of the mandrel 1 is smaller than the outer diameter of the mandrel 1, so that the mandrel 1 can pass through the rolling conveyor roller. The rod insertion pusher 202 is rotatably connected to the rod insertion device body 201 through the hinge shaft 203, and a first driving device for driving the hinge shaft 203 to rotate is provided at both ends of the hinge shaft 203 to realize the rotation of the rod insertion pusher 202, thereby realizing the detachable connection between the rod insertion pusher 202 and the mandrel 1. The first driving device can specifically be a hydraulic motor.

[0032] In another embodiment, the rod pushing head 202 is rotated by an external opening device, thereby achieving a detachable connection between the rod pushing head 202 and the core rod 1 .

[0033] Specifically, the body 201 of the rod threading device includes a first driving rack and a first gear set for driving the first driving rack. The rod threading push head 202 is hinged to the first driving rack. The limiting driving device includes a second driving rack 303 and a second gear set 308 for driving the second driving rack 303. The limiting clamping head is fixedly connected to the second driving rack 303. The limiting driving device further includes a fixed frame 307 for installing the second rack, a roller set 304 installed on the second driving rack 303, and a guide wheel connected to the roller set 304. The roller set 304 is located on two adjacent sides of the side of the second driving rack 303 that meshes with the second gear set 308 and is slidably connected to the fixed frame 307. A bed 306 for slidably connecting the roller set 304 and the guide wheel is provided on the fixed frame 307 to realize the sliding connection between the second driving rack 303 and the fixed frame 307. The lower part of the second driving rack 303 is processed with teeth, the side is the roller set 304, and a side guide wheel 305 is provided. The limiting clamping head is fixedly connected to the top of the second driving rack 303 and moves on the bed 306 under the drive of the second gear set 308. The first gear set and the second gear set 308 are driven by an external driving motor.

[0034] Further, the limiting clamping head includes a clamping head body 301 and a fixed limiting frame 302 for installing the clamping head body 301. The clamping head body 301 is opened or closed under the action of the second driving device to realize the clamping or blanking of the mandrel 1. The fixed limiting frame 302 is connected to the limiting driving device to realize the limiting rolling of the mandrel 1. The second driving device may specifically be a hydraulic driving device, which cooperates with the clamping head body 301 to form a hydraulic clamp.

[0035] In the rolling process of the double-step mandrel limiting device provided in this embodiment, the specific steps are as follows:

[0036] Both the mandrel 1 and the tube billet 4 are moved into the rolling line; the tube feeding device 2 is connected to the mandrel 1 through the tube feeding pusher 202, and the mandrel 1 is pushed to penetrate into the tube billet 4 at high speed, and then runs at a reduced speed to a preset position; the limit clamping device 3 is started. During the deceleration process of the tube feeding device 2, when the running speed matches the speed of the limit clamping device 3, the tube feeding pusher 202 is lifted, the tube feeding device 2 is separated from the mandrel 1, and it retracts to the tube feeding position to wait for the next rolling cycle. At the same time, the limit clamping device 3 clamps the second stepped shaft 102 of the mandrel 1 and starts to run for limit rolling; after the rolling is completed, the limit clamping device 3 clamps the mandrel 1 and retracts at high speed to the discharging position (retracting a distance equal to the length of one mandrel). While the external mandrel discharging device clamps the mandrel 1 to discharge, the subsequent tube billet 4 and the mandrel 1 are moved in simultaneously to complete a rolling cycle. It should be noted that the rolling conveyor roller table is a lifting roller table, which cooperates with the limit clamping device 3 during the limit rolling process to avoid movement interference.

[0037] A mandrel limit device in this embodiment adopts two-stage on-line tube feeding and rolling. During the limit rolling process, the tube feeding device 2 can return to the waiting position without occupying the rolling cycle time; after the rolling is completed, the limit clamping device 3 clamps the mandrel 1 and retracts at high speed. After the mandrel 1 exits the rolling mill, the mandrel discharging device can move the mandrel 1 out of the rolling center line and enter the next cycle, shortening the rolling cycle and improving the production efficiency of seamless steel pipe rolling.

[0038] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the purpose and scope of the present technical solution, and they should all be covered by the scope of the claims of the present invention.

Claims

1. A mandrel restraining device, comprising a rolling conveyor roller path arranged on the rolling center line, one end of the rolling conveyor roller path is docked with a rolling mill, and a rod threading device (2) is arranged at the other end. A restraining and clamping device (3) is arranged between the rod threading device (2) and the rolling mill. The mandrel (1) is clamped and fixed by the restraining and clamping device (3) for restraining rolling. It is characterized in that: The tail of the mandrel (1) is provided with two stepped shafts, namely a first stepped shaft (101) and a second stepped shaft (102), and the outer diameter of the mandrel (1) is consistent. The outer diameters of the two stepped shafts at the tail of the mandrel (1) are smaller than the outer diameter of the mandrel (1) so that the mandrel (1) can pass through the rolling conveying roller table; The rod piercing device (2) includes a rod piercing device body (201) and a rod piercing push head (202). One end of the rod piercing device body (201) close to the mandrel (1) is in contact connection with the tail end of the mandrel (1). The rod piercing push head (202) is rotatably connected to the rod piercing device body (201) through a hinge shaft (203), and is in a horizontal state without external force, and is clamped on the first stepped shaft (101) to realize the detachable connection between the rod piercing device (2) and the mandrel (1); The restraining and clamping device (3) includes a restraining and clamping head and a restraining driving device for driving the restraining and clamping head. The front end of the mandrel (1) passes through the restraining and clamping head, and the restraining and clamping head clamps and fixes the second stepped shaft (102) at the tail of the mandrel (1), and is in contact connection with the two side steps of the second stepped shaft (102) to realize the restraining rolling of the mandrel (1); The rolling process of this mandrel restraining device is as follows: Both the mandrel and the billet are moved into the rolling line; The rod piercing device is connected to the mandrel through the rod piercing push head, and the mandrel is pushed to quickly penetrate into the billet, and then runs at a reduced speed to a preset position; Start the restraining and clamping device. During the deceleration process of the rod piercing device, when the running speed matches the speed of the restraining and clamping device, the rod piercing push head is lifted, the rod piercing device is separated from the mandrel, and retreats to the rod piercing position to wait for the next rolling cycle. At the same time, the restraining and clamping device clamps the second stepped shaft of the mandrel and starts to run for restraining rolling; After rolling, the restraining and clamping device clamps the mandrel and quickly retreats to the blanking position. While the external mandrel blanking device clamps the mandrel to discharge, the subsequent billet and mandrel are simultaneously moved in to complete a rolling cycle.

2. The mandrel stopper device according to claim 1, characterized in that: Both ends of the hinge shaft (203) are provided with a first driving device for driving the rotation of the hinge shaft (203) to realize the rotation of the rod piercing push head (202), so as to realize the detachable connection between the rod piercing push head (202) and the mandrel (1).

3. The mandrel stop device according to claim 1, characterized in that: The rod piercing device body (201) includes a first driving rack and a first gear set for driving the first driving rack. The rod piercing push head (202) is hinged on the first driving rack.

4. The mandrel stop device according to claim 1, characterized in that: A guiding inclined surface (103) is provided between the tail end of the mandrel (1) and the first stepped shaft (101) to facilitate the clamping of the rod piercing push head (202) and the first stepped shaft (101).

5. The mandrel stop device according to claim 1, characterized in that: The restraining and clamping head includes a clamping head body (301) and a fixed restraining frame (302) for installing the clamping head body (301). The clamping head body (301) is opened or closed under the action of a second driving device to realize the clamping or blanking of the mandrel (1). The fixed restraining frame (302) is connected to the restraining driving device to realize the restraining rolling of the mandrel (1).

6. The mandrel stop device according to claim 1, wherein: The limiting driving device includes a second driving rack (303) and a second gear set (308) for driving the second driving rack (303), and the limiting clamping head is fixedly connected to the second driving rack (303).

7. The mandrel stopper device according to claim 6, wherein: The limiting driving device further includes a fixed frame (307) for mounting the second rack, a roller set (304) mounted on the second driving rack (303), and a guide wheel connected to the roller set (304). The roller set (304) is located on two adjacent sides of the side of the second driving rack (303) that meshes with the second gear set (308), and is slidably connected to the fixed frame (307).

8. The mandrel stopper device according to claim 7, wherein: A bed (306) slidably connected to the roller set (304) and the guide wheel is provided on the fixed frame (307) to realize the sliding connection between the second driving rack (303) and the fixed frame (307).

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