Internal finishing device for nodular cast iron pipe

Abstract

The utility model relates to the technical field of nodular cast iron pipe production, and discloses a nodular cast iron pipe interior finishing device. A support assembly; the cleaning assembly comprises a cleaning rod, a follow-up plate, a positioning plate, first air holes, second air holes, a plug and an ejector rod, the positioning plate is fixedly connected with the cleaning rod, the follow-up plate is rotationally connected with the positioning plate, the wall face of the positioning plate is provided with a plurality of first air holes, and the wall face of the follow-up plate is provided with a plurality of second air holes; due to the fact that the interior of the iron pipe is in a negative pressure state, part of airflow can enter the first air hole from the second air hole, the bundle-shaped airflow impacts the inner wall of the iron pipe to wash impurities towards the other end of the iron pipe, and after the first air hole and the second air hole are staggered, air enters from a gap between the follow-up plate and the inner wall of the iron pipe, and the first air hole and the second air hole are continuously aligned and staggered. Therefore, discontinuous bundle-shaped airflow is formed to wash the inner wall of the iron pipe, and a better cleaning effect is achieved.

Description

Technical Field

[0001] The utility model relates to the technical field of ductile iron pipe production, in particular to an internal finishing device for a ductile iron pipe. Background Art

[0002] The essence of cast iron steel pipe is ductile iron pipe. Because ductile iron pipe has the nature of iron and the properties of steel, it needs to be polished during the production and processing of ductile iron pipe, and polishing and finishing of the inner wall is one of them.

[0003] The prior art discloses a finishing grinding unit (publication number: CN115555930A), wherein a first slot is provided at the top of a base, a first driving screw is installed inside the first slot, a first threaded sleeve is threadedly sleeved on the first driving screw, a driving platform is fixedly connected to the top of the first threaded sleeve, the right end of the base protrudes upward, a tube clamping mechanism is provided on the inner sides of the driving platform and the right end of the base, a rotating shaft is installed at the center of the outer side of the right tube clamping mechanism, a second slot is provided at the bottom of the top platform, a second driving screw is installed inside the second slot, a second threaded sleeve is threadedly sleeved on the second driving screw, a cylinder is installed at the bottom of the second threaded sleeve, and a grinding assembly is installed at the bottom end of the cylinder.

[0004] The prior art mainly grinds the outer wall of the iron pipe by clamping the two ends thereof, but the inner wall of the iron pipe also needs to be trimmed. Although the rotating iron pipe can be cleaned and trimmed by extending a cleaning rod into the inner wall of the iron pipe, the cleaned impurities will accumulate in the cavity of the iron pipe. After the overall trimming is completed, it is necessary to concentrate on cleaning the impurities inside the iron pipe, which is inconvenient.

[0005] For this purpose, we propose a device for internal finishing of ductile iron pipe. Utility Model Content

[0006] The utility model mainly solves the above-mentioned technical problems that it is inconvenient to trim the inner wall of the iron pipe and it is inconvenient to centrally clean the impurities on the inner wall, and provides a ductile iron pipe internal finishing device.

[0007] In order to achieve the above purpose, the utility model adopts the following technical scheme, a ductile iron pipe internal finishing device, comprising:

[0008] Workbench, frame structure for support;

[0009] A support assembly is arranged above the workbench for limiting and driving the iron pipe to rotate, and the support assembly includes two rollers that are symmetrically arranged and can approach each other; a pressing roller arranged above the two rollers, and the pressing roller can be raised and lowered to press the iron pipe between the two rollers;

[0010] A cleaning component is arranged on the side of a workbench and is used to clean the inner wall of an iron pipe. The cleaning component comprises a cleaning rod, a follower plate, a positioning plate, a first air hole, a second air hole, a plug and a push rod. The push rod is movably installed on one side of the workbench, and the push rod can be translated and inserted into the inside of the iron pipe. The positioning plate is fixedly connected to the cleaning rod, and the follower plate is rotatably connected to the positioning plate. A plurality of first air holes are provided on the wall surface of the positioning plate, and a plurality of second air holes are provided on the wall surface of the follower plate. The second air holes can be rotated to face the first air holes. The plug is arranged on the other side of the workbench and is connected to a negative pressure device. The plug is inserted into one end of the iron pipe and air is pumped into the inside of the iron pipe. The cleaning rod enters from the other end of the iron pipe and cleans the inner wall of the iron pipe. The follower plate can rotate with the iron pipe. The push rod is movably arranged on one side of the positioning plate and the push rod can contact the inner wall of the iron pipe.

[0011] As a preferred embodiment of the utility model, the cleaning rod forms a rectangular rod body structure, a rack is fixedly installed on one side of the cleaning rod, a driving device is fixedly installed on one side of the workbench, the driving device includes a shell, the shell is adapted to the cleaning rod, the cleaning rod is slidably connected to the shell, a motor is fixedly installed in the shell, a gear is fixedly provided on the motor output shaft, and the gear is meshed with the rack.

[0012] As a preferred embodiment of the utility model, the cleaning assembly also includes an elastic member, which includes an elastic telescopic rod but is not limited to an elastic telescopic rod, the elastic telescopic rod is fixedly mounted on the side wall of the follower plate, and the output shaft of the elastic telescopic rod can contact the inner wall of the iron pipe.

[0013] As a preferred embodiment of the utility model, the follower plate and the positioning plate are both circular plate structures, the end face of the positioning plate is provided with a plurality of first air holes in a circular array, the end face of the follower plate is provided with a plurality of second air holes in a circular array, the first air holes and the second air holes are located on the same circumference, a rotating shaft is fixedly installed on the end face of the positioning plate, a circular hole is provided at the midline position of the follower plate, the rotating shaft passes through the circular hole and is fixedly connected to the cleaning rod, and the follower plate is rotatably connected to the rotating shaft.

[0014] As a preferred embodiment of the utility model, the cleaning assembly also includes a limit groove, two limit grooves are opened on the end face of the positioning plate, the same push rod is arranged in each limit groove, a spring is fixedly installed on the end of the push rod, and the other end of the spring is fixedly connected to the inner wall of the positioning plate, and the spring can push the push rod to contact the inner wall of the iron pipe.

[0015] As a preferred embodiment of the present invention, the push rod forms a rectangular rod structure, the limiting groove is matched with the push rod, and the limiting groove extends obliquely toward the circumference of the positioning plate.

[0016] As a preferred embodiment of the utility model, the support assembly also includes a first mounting seat, a push cylinder, a telescopic pull rod and a second connecting seat. A crossbeam is fixedly installed on the top surface of the workbench, and the push cylinder and the telescopic pull rod are fixedly installed on the crossbeam. The output shafts of the push cylinder and the telescopic pull rod are fixedly connected to the top surface of the first mounting seat. The two ends of the pressure roller are rotatably connected to the first mounting seat, the top of the workbench is slidably connected to two second connecting seats, and the two rollers are respectively rotatably connected to the two second connecting seats. A screw is provided on the top of the workbench to drive the two second connecting seats to move toward each other.

[0017] As a preferred embodiment of the utility model, a slide groove is provided on the top surface of the workbench, two sliders are slidably connected in the slide groove, two second connecting seats are fixedly connected to the corresponding sliders, the sliders are provided with threaded holes, the screw rod is threadedly connected to the sliders, the end of the screw rod is rotatably connected to the workbench, an active motor is fixedly installed on one side of the workbench, and the output shaft of the active motor is fixedly connected to the screw rod.

[0018] Beneficial Effects

[0019] The utility model provides a device for finishing the interior of a ductile iron pipe, which has the following beneficial effects:

[0020] 1. A device for finishing the interior of a ductile iron pipe drives a follower plate to rotate by a rotating iron pipe. When the second air hole is directly opposite to the first air hole, due to the negative pressure in the iron pipe, part of the air flow will enter the first air hole from the second air hole, and the beam-like air flow will impact the inner wall of the iron pipe and then flush the impurities toward the other end of the iron pipe. When the first air hole and the second air hole are misaligned, the gas enters from the gap between the follower plate and the inner wall of the iron pipe, and the first air hole and the second air hole are continuously aligned and misaligned, thereby forming an intermittent beam-like air flow to flush the inner wall of the iron pipe, which has a better cleaning effect.

[0021] 2. The internal finishing device of the ductile iron pipe can ensure that the follower plate rotates synchronously with the iron pipe by the output shaft of the elastic member abutting against the inner wall of the iron pipe, thereby ensuring that the follower plate and the positioning plate form relative motion to generate beam-shaped airflow.

[0022] 3. This internal finishing device for ductile iron pipes is provided with a limit groove, and a spring is used to push the push rod to slide in the limit groove, thereby ensuring that the push rod can contact the inner wall of the iron pipe, and has better adaptability. At the same time, it can ensure that the push rod is in full contact with the iron pipe to ensure the cleaning effect.

[0023] 4. This internal finishing device for ductile iron pipes pushes the first mounting seat down through a push cylinder, and the first mounting seat drives the output shaft of the telescopic pull rod to move downward so that the first mounting seat maintains a linear displacement, so that the pressure roller can move to contact the iron pipe, and cooperate with the active motor to drive the lead screw to move the two sliders closer to each other, and the two pressure rollers are close to support the outer circumference of the steel pipe to achieve the limitation of steel pipes of different diameters. Another motor is fixedly installed on one side of the first mounting seat, and the output shaft of the motor is fixedly connected to the end of the pressure roller, so that the pressure roller can drive the iron pipe to rotate between the two rollers. The motor specifications are not too restricted here, and it has better production adaptability and flexibility of use, and is more adjustable. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is one of the overall three-dimensional diagrams of the utility model;

[0025] Figure 2 This is the second overall stereogram of the utility model;

[0026] Figure 3 This is a schematic diagram of removing the crossbeam from the workbench of the utility model;

[0027] Figure 4 This is a three-dimensional diagram of the follower plate, the positioning plate and the cleaning rod of the utility model;

[0028] Figure 5 This is a three-dimensional diagram of the positioning plate of the utility model;

[0029] Figure 6 This is a three-dimensional diagram of the follower plate.

[0030] Legend: 10. Workbench; 11. Support roller; 12. Pressure roller; 13. First mounting seat; 14. Push cylinder; 15. Telescopic pull rod; 16. Second connecting seat; 20. Cleaning rod; 21. Follower plate; 22. Positioning plate; 23. First air hole; 24. Second air hole; 25. Elastic member; 26. Plug; 30. Push rod; 31. Limiting groove. DETAILED DESCRIPTION

[0031] A ductile iron pipe internal finishing device, such as Figure 1 and Figure 2 As shown, including:

[0032] Workbench 10, a frame structure for support;

[0033] A support assembly is arranged above the workbench 10 for limiting and driving the iron pipe to rotate. The support assembly includes two rollers 11 that are symmetrically arranged and can approach each other; a pressing roller 12 is arranged above the two rollers 11, and the pressing roller 12 can be raised and lowered to press the iron pipe between the two rollers 11;

[0034] like Figure 3 , Figure 4 , Figure 5 and Figure 6As shown, the cleaning assembly is arranged on the side of the workbench 10 for cleaning the inner wall of the iron pipe. The cleaning assembly includes a cleaning rod 20, a follower plate 21, a positioning plate 22, a first air hole 23, a second air hole 24, a plug 26 and a push rod 30. The push rod 30 is movably installed on one side of the workbench 10, and the push rod 30 can be translated and inserted into the inside of the iron pipe. The positioning plate 22 is fixedly connected to the cleaning rod 20, and the follower plate 21 is rotatably connected to the positioning plate 22. A plurality of first air holes 23 are provided on the wall surface of the positioning plate 22, and a plurality of second air holes 24 are provided on the wall surface of the follower plate 21. The second air holes 24 can be rotated to face the first air holes 23. The plug 26 is arranged on the other side of the workbench 10 and connected to the negative pressure device. The plug 26 is plugged into one end of the iron pipe and the inside of the iron pipe is evacuated. The negative pressure The device can be a centrifugal fan, the plug 26 is made of rubber, the cleaning rod 20 enters from the other end of the iron pipe and cleans the inner wall of the iron pipe, the follower plate 21 can rotate with the iron pipe, the push rod 30 is movably arranged on one side of the positioning plate 22 and the push rod 30 can contact the inner wall of the iron pipe, the cleaning rod 20 forms a rectangular rod body structure, a rack is fixedly installed on one side of the cleaning rod 20, a driving device is fixedly installed on one side of the workbench 10, the driving device includes a shell, the shell is adapted to the cleaning rod 20, the cleaning rod 20 is slidably connected to the shell, a motor is fixedly installed in the shell, a gear is fixedly provided on the output shaft of the motor, the gear is meshed with the rack, the follower plate 21 and the positioning plate 22 are both circular plate structures, the end face of the positioning plate 22 is provided with a plurality of first air holes 23 in a ring array, and the follower plate 21 The end surface is provided with a plurality of second air holes 24 in an annular array, the first air holes 23 and the second air holes 24 are located on the same circumference, a rotating shaft is fixedly installed on the end surface of the positioning plate 22, a circular hole is provided at the midline position of the follower plate 21, the rotating shaft passes through the circular hole and is fixedly connected to the cleaning rod 20, and the follower plate 21 is rotatably connected to the rotating shaft. In this scheme, the cleaning rod 20 and the follower plate 21 are driven to move linearly in the iron pipe mainly by rotating the iron pipe, and the motor for driving the gear is a stepping motor, so that the inside of the iron pipe can be gradually cleaned, and the stepping motor drives the gear to move the cleaning rod 20 to slide along the shell, and the cleaning rod 20 gradually enters the inside of the iron pipe, and generates relative movement through the push rod 30 against the inner wall of the iron pipe, so as to achieve scraping cleaning and remove the attached Of course, a grinding wheel or an iron pipe can be installed at the end of the push rod 30 for grinding, or a rubber block can be installed for simple cleaning. The push rod 30 has two, and a grinding wheel can be installed at the end of one push rod 30, and a rubber block can be installed at the end of the other push rod 30 to achieve grinding and cleaning at the same time. A threaded hole is opened at the end of the push rod 30, and the grinding wheel or the rubber block is locked by a bolt. The rotating iron pipe drives the follower plate 21 to rotate. When the second air hole 24 is facing the first air hole 23, due to the negative pressure in the iron pipe, part of the air flow will enter the first air hole 23 from the second air hole 24, and the beam-shaped air flow will impact the inner wall of the iron pipe and then flush the impurities toward the other end of the iron pipe. When the first air hole 23 and the second air hole 24 are misaligned, the gas enters from the gap between the follower plate 21 and the inner wall of the iron pipe.The first air hole 23 and the second air hole 24 are constantly aligned and staggered, thereby forming an intermittent beam-like airflow to flush the inner wall of the iron pipe, which has a better cleaning effect.

[0035] like Figure 4 As shown, the cleaning assembly also includes an elastic member 25, which includes an elastic telescopic rod but is not limited to an elastic telescopic rod. The elastic telescopic rod is fixedly mounted on the side wall of the follower plate 21, and the output shaft of the elastic telescopic rod can abut against the inner wall of the iron pipe. By abutting the inner wall of the iron pipe with the output shaft of the elastic member 25, the follower plate 21 can be ensured to rotate synchronously with the iron pipe, thereby ensuring that the follower plate 21 and the positioning plate 22 form a relative motion to generate a beam of airflow.

[0036] like Figure 4 and Figure 5 As shown, the cleaning component also includes a limit groove 31. Two limit grooves 31 are provided on the end face of the positioning plate 22. The same push rod 30 is arranged in each limit groove 31. A spring is fixedly installed on the end of the push rod 30. The other end of the spring is fixedly connected to the inner wall of the positioning plate 22. The spring can push the push rod 30 to contact the inner wall of the iron pipe. The push rod 30 forms a rectangular rod structure. The limit groove 31 is adapted to the push rod 30. The limit groove 31 extends obliquely toward the circumference of the positioning plate 22. By setting the limit groove 31, the spring pushes the push rod 30 to slide in the limit groove 31, thereby ensuring that the push rod 30 can contact the inner wall of the iron pipe, having better adaptability. At the same time, it can ensure that the push rod 30 is in full contact with the iron pipe and thus ensure the cleaning effect.

[0037] like Figure 1 , Figure 2 as well as Figure 3As shown, the support assembly also includes a first mounting seat 13, a push cylinder 14, a telescopic pull rod 15 and a second connecting seat 16. A crossbeam is fixedly installed on the top surface of the workbench 10. The push cylinder 14 and the telescopic pull rod 15 are fixedly installed on the crossbeam. The output shafts of the push cylinder 14 and the telescopic pull rod 15 are fixedly connected to the top surface of the first mounting seat 13. The two ends of the pressure roller 12 are rotatably connected to the first mounting seat 13. The top of the workbench 10 is slidably connected to the two second connecting seats 16. The two rollers 11 are rotatably connected to the two second connecting seats 16 respectively. A screw is provided on the top of the workbench 10 to drive the two second connecting seats 16 to move toward each other. A slide groove is provided on the top surface of the workbench 10. Two sliders are slidably connected in the slide groove. The two second connecting seats 16 are fixedly connected to the corresponding sliders. The sliders are provided with threaded holes. The screw is threadedly connected to the sliders. The end of the rod is rotatably connected to the workbench 10, and an active motor is fixedly installed on one side of the workbench 10. The output shaft of the active motor is fixedly connected to the screw rod, and the first mounting seat 13 is pushed down by the push cylinder 14. The first mounting seat 13 drives the output shaft of the telescopic pull rod 15 to move downward so that the first mounting seat 13 maintains a linear displacement, and then the pressure roller 12 can move to contact the iron pipe, and cooperate with the active motor to drive the screw rod to move the two sliders closer to each other. The two pressure rollers 12 are close to the outer circumference of the steel pipe to achieve the limitation of steel pipes of different diameters. Another motor is fixedly installed on one side of the first mounting seat 13, and the output shaft of the motor is fixedly connected to the end of the pressure roller 12, and then the pressure roller 12 can drive the iron pipe to rotate between the two rollers 11. The motor specifications are not restricted too much here, and it has better production adaptability and flexibility of use, and is more adjustable.

[0038] The working principle of the utility model is as follows: the push cylinder 14 pushes the first mounting seat 13 to descend, and the first mounting seat 13 drives the output shaft of the telescopic pull rod 15 to move downward so that the first mounting seat 13 maintains linear displacement, and then the pressure roller 12 can move to contact the iron pipe, cooperate with the active motor to drive the screw rod to move the two sliders close to each other, and the two pressure rollers 12 are close to support the outer circumference of the steel pipe to achieve the limit of steel pipes of different diameters. Another motor is fixedly installed on one side of the first mounting seat 13, and the motor output shaft is fixedly connected to the end of the pressure roller 12, so that the pressure roller 12 can drive the iron pipe to rotate between the two rollers 11, and the plug 26 is inserted into the other end of the iron pipe. The motor of the driving gear is a stepping motor, which can realize the gradual cleaning of the inside of the iron pipe. The stepping motor drives the gear to move the cleaning rod 20 to slide along the shell, and the cleaning rod 20 gradually enters the inside of the iron pipe. The spring pushes the top rod 30 to slide in the limiting groove 31 to ensure The push rod 30 can contact the inner wall of the iron pipe. The push rod 30 has two ends. A grinding wheel can be installed at the end of one push rod 30, and a rubber block can be installed at the end of the other push rod 30 to achieve grinding and cleaning at the same time. A threaded hole is opened at the end of the push rod 30, and the grinding wheel or the rubber block is locked by a bolt. The rotating iron pipe drives the follower plate 21 to rotate. When the second air hole 24 is opposite to the first air hole 23, due to the negative pressure state in the iron pipe, part of the air flow will enter the first air hole 23 from the second air hole 24, and the beam air flow will impact the inner wall of the iron pipe and then flush the impurities toward the other end of the iron pipe. When the first air hole 23 and the second air hole 24 are misaligned, the gas enters from the gap between the follower plate 21 and the inner wall of the iron pipe, and the first air hole 23 and the second air hole 24 are continuously aligned and misaligned, thereby forming an intermittent beam air flow to flush the inner wall of the iron pipe, and the cleaned impurities are concentrated and pushed to the end where the plug 26 is located. After the fine finishing is completed, the impurities can be poured out.

[0039] The above shows and describes the basic principle and main features of the utility model and the advantages of the utility model. Those skilled in the art should understand that the utility model is not limited by the above embodiments. The above embodiments and descriptions are only for explaining the principle of the utility model. Without departing from the spirit and scope of the utility model, the utility model may have various changes and improvements, which fall within the scope of the utility model to be protected. The scope of protection claimed by the utility model is defined by the attached claims and their equivalents.

Claims

1. A ductile iron pipe internal finishing device, characterized in that: include: A workbench (10), a frame structure for supporting; A support assembly is arranged above the workbench (10) and is used for limiting and driving the iron pipe to rotate, the support assembly comprising two rollers (11) which are symmetrically arranged and can approach each other; a pressing roller (12) is arranged above the two rollers (11), and the pressing roller (12) can be raised and lowered and press the iron pipe between the two rollers (11); A cleaning assembly is arranged on the side of a workbench (10) for cleaning the inner wall of an iron pipe. The cleaning assembly comprises a cleaning rod (20), a follower plate (21), a positioning plate (22), a first air hole (23), a second air hole (24), a plug (26) and a push rod (30). The push rod (30) is movably installed on one side of the workbench (10). The push rod (30) can be translated and inserted into the inside of the iron pipe. The positioning plate (22) is fixedly connected to the cleaning rod (20), the follower plate (21) is rotatably connected to the positioning plate (22), and a wall surface of the positioning plate (22) is provided with a plurality of The first air hole (23) is provided on the wall of the follower plate (21), and a plurality of second air holes (24) are provided, and the second air holes (24) can be rotated to face the first air holes (23). The plug (26) is arranged on the other side of the workbench (10) and connected to the negative pressure device. The plug (26) is inserted into one end of the iron pipe and evacuates air from the inside of the iron pipe. The cleaning rod (20) enters from the other end of the iron pipe and cleans the inner wall of the iron pipe. The follower plate (21) can rotate with the iron pipe. The push rod (30) is movably arranged on one side of the positioning plate (22) and the push rod (30) can contact the inner wall of the iron pipe.

2. The ductile iron pipe internal finishing device according to claim 1, characterized in that: The cleaning rod (20) forms a rectangular rod body structure, a rack is fixedly mounted on one side of the cleaning rod (20), a driving device is fixedly mounted on one side of the workbench (10), the driving device comprises a shell, the shell is adapted to the cleaning rod (20), the cleaning rod (20) is slidably connected to the shell, a motor is fixedly mounted in the shell, a gear is fixedly mounted on the output shaft of the motor, and the gear is meshed with the rack.

3. The ductile iron pipe internal finishing device according to claim 1, characterized in that: The cleaning assembly also includes an elastic member (25), which includes an elastic telescopic rod but is not limited to the elastic telescopic rod. The elastic telescopic rod is fixedly mounted on the side wall of the follower plate (21), and the output shaft of the elastic telescopic rod can contact the inner wall of the iron pipe.

4. The ductile iron pipe internal finishing device according to claim 1, characterized in that: The following plate (21) and the positioning plate (22) are both circular plate structures. The end surface of the positioning plate (22) is provided with a plurality of first air holes (23) in a circular array. The end surface of the following plate (21) is provided with a plurality of second air holes (24) in a circular array. The first air holes (23) and the second air holes (24) are located on the same circumference. A rotating shaft is fixedly mounted on the end surface of the positioning plate (22). A circular hole is provided at the midline position of the following plate (21). The rotating shaft passes through the circular hole and is fixedly connected to the cleaning rod (20). The following plate (21) is rotatably connected to the rotating shaft.

5. The ductile iron pipe internal finishing device according to claim 1, characterized in that: The cleaning assembly further comprises a limiting groove (31), the end surface of the positioning plate (22) is provided with two limiting grooves (31), each limiting groove (31) is provided with an identical push rod (30), a spring is fixedly installed at the end of the push rod (30), the other end of the spring is fixedly connected to the inner wall of the positioning plate (22), and the spring can push the push rod (30) to contact the inner wall of the iron pipe.

6. The ductile iron pipe internal finishing device according to claim 5, characterized in that: The push rod (30) forms a rectangular rod structure, the limiting groove (31) is matched with the push rod (30), and the limiting groove (31) extends obliquely toward the circumference of the positioning plate (22).

7. The ductile iron pipe internal finishing device according to claim 1, characterized in that: The support assembly also includes a first mounting seat (13), a push cylinder (14), a telescopic pull rod (15) and a second connecting seat (16). A crossbeam is fixedly mounted on the top surface of the workbench (10). The push cylinder (14) and the telescopic pull rod (15) are both fixedly mounted on the crossbeam. The output shafts of the push cylinder (14) and the telescopic pull rod (15) are both fixedly connected to the top surface of the first mounting seat (13). Both ends of the pressure roller (12) are rotatably connected to the first mounting seat (13). The top of the workbench (10) is slidably connected to the two second connecting seats (16). The two rollers (11) are respectively rotatably connected to the two second connecting seats (16). A screw is provided on the top of the workbench (10) to drive the two second connecting seats (16) to move toward each other.

8. The device for finishing the interior of a ductile iron pipe according to claim 7, characterized in that: The top surface of the workbench (10) is provided with a slide groove, in which two sliders are slidably connected, and two second connecting seats (16) are fixedly connected to the corresponding sliders. The sliders are provided with threaded holes, and the screw rods are threadedly connected to the sliders. The ends of the screw rods are rotatably connected to the workbench (10). An active motor is fixedly installed on one side of the workbench (10), and the output shaft of the active motor is fixedly connected to the screw rod.

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