CN214078476U - Three-roller centering device with high-precision positioning function - Google Patents

Three-roller centering device with high-precision positioning function Download PDF

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CN214078476U
CN214078476U CN202023031001.2U CN202023031001U CN214078476U CN 214078476 U CN214078476 U CN 214078476U CN 202023031001 U CN202023031001 U CN 202023031001U CN 214078476 U CN214078476 U CN 214078476U
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servo cylinder
roller
centering
piston
vertical plate
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徐永平
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TAIYUAN TONGZE HEAVY INDUSTRY CO LTD
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TAIYUAN TONGZE HEAVY INDUSTRY CO LTD
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Abstract

The invention discloses a three-roller centering device for high-precision positioning, which solves the problem of low positioning precision of the existing equipment. The traditional structure that three rollers are synchronously driven through a link mechanism on a puncher is changed, each centering roller is connected to the piston of each independent servo cylinder, the three independent servo cylinders are communicated with the same hydraulic system, and the synchronous stretching and retraction of the pistons of the three independent servo cylinders are realized by controlling the hydraulic oil of the hydraulic system; the other end of the piston of the independent servo cylinder is connected with a hydraulic motor, the rotation of the piston is realized by controlling the hydraulic motor, and the independent adjustment of the respective angles of the three rollers is realized by the respective hydraulic motors connected to the respective servo cylinders, so that the change of the angle between the centering roller and the rolling line is realized. The centering roller has a simple structure, and the servo cylinder improves the positioning precision of the centering roller.

Description

Three-roller centering device with high-precision positioning function
Technical Field
The invention relates to seamless steel tube production equipment, in particular to a three-roller centering device with high-precision positioning and a positioning adjustment method thereof.
Background
When the seamless steel tube piercing mill set is used for piercing and rolling a steel tube, the mainly used rolling tools comprise deformation tools such as a roller, a top, a guide plate and the like; the two rollers are arranged up and down or left and right, a feeding angle and a rolling angle of the pipe blank are formed in space, the guide plates are arranged left and right or up and down, the two guide plates and the two rollers form a closed rolling pass, the ejector head is arranged at the head part of the ejector rod, the ejector rod is abutted to the perforated solid pipe blank through the ejector head, the solid pipe blank is rolled and rotated under the rolling of the two rollers, and the rolled pipe blank is sleeved on the ejector rod; in the tube-piercing rolling, a mandril and a top head are required to be positioned at the central position of an annular rolling space formed by two rollers and two guide plates, namely on a rolling central line, in order to achieve the purpose, the prior art is that a plurality of three-roller centering devices are arranged on a rack at equal intervals, and the three centering rollers of the three-roller centering devices synchronously clamp the top mandril so as to ensure that the mandril is always positioned on the rolling central line in the piercing rolling; the structure of the traditional three-roller centering device is as follows: three centering rollers are arranged on the chassis of the same centering device, the three centering rollers are arranged at intervals of 120 degrees in radian, the three centering rollers realize synchronous clamping on the ejector rod through a link mechanism, or synchronously open and then move away from the ejector rod, the synchronous action and the installation precision of the link mechanism directly determine the accurate positioning of the ejector rod on a rolling center line, and the existing three-roller centering device has the following problems: (1) the joint part of the connecting rod mechanism adopts a copper sleeve or a joint bearing, so that the defect of short service life exists, and the connecting rod mechanism needs to be frequently replaced in work; the connecting rod mechanism has mechanical installation matching errors, the high-precision realization of the positioning positions of the three rollers cannot be ensured, and new position deviation can occur in the operation process; (2) when the three rollers clamp the ejector rod, the centering rollers are in line contact with the ejector rod, and the problem of poor centering stability exists; (3) when the ejector rod and the capillary tube retreat, the three centering rollers cannot provide a retreat conveying track for the ejector rod and the capillary tube, and the retreat conveying roller way is additionally and independently arranged on a rolling line to finish the retreat of the ejector rod and the capillary tube in the prior art, so that the equipment structure is complex and the equipment investment cost is high.
Disclosure of Invention
The invention provides a three-roller centering device with high-precision positioning and a positioning adjusting method thereof, which solve the technical problems that the positioning precision is low and a positioning roller cannot provide a returning conveying track for returning a capillary tube in the existing equipment.
The invention solves the technical problems by the following technical scheme:
the general concept of the invention is as follows: the positioning precision of the invention can reach micron level, the complete coincidence of the mandril and the rolling center line is ensured, the mechanical abrasion is avoided, and the service life of the centering roller is prolonged; the other end of the piston of the independent servo cylinder is connected with a hydraulic motor, the rotation of the piston is realized by controlling the hydraulic motor, and the independent adjustment of the respective angles of the three rollers is realized by the respective hydraulic motors connected to the respective servo cylinders, so that the change of the angle between the centering roller and the rolling line is realized; when the ejector rod drives the capillary to retreat, the centering roller is rotated to be perpendicular to the ejector rod, so that the centering roller can be used as a conveying roller, a retreat conveying roller way is not required to be arranged in the equipment, and the capillary retreat operation by utilizing the centering roller is realized; in addition, the roller surface of the centering roller is set to be a curved surface which is inwards concave and returns, and the centering roller and the ejector rod form envelope line contact in the circumferential direction in the guiding process of clamping the ejector rod or the capillary tube, so that the stability of the capillary tube in the rotating forward process is greatly enhanced, the quality of the perforated capillary tube is improved, and the wall thickness deviation of the capillary tube in rolling is reduced.
A three-roller centering device with high-precision positioning comprises a hydraulic system and a frame bottom plate, wherein a rear vertical plate and a front vertical plate are fixedly arranged on the frame bottom plate in parallel, a rear vertical plate U-shaped groove is arranged at the top end of the rear vertical plate, a front vertical plate U-shaped groove is arranged at the top end of the front vertical plate, the rear vertical plate U-shaped groove and the front vertical plate U-shaped groove are correspondingly arranged, a bottom servo cylinder mounting plate, a left servo cylinder mounting plate and a right servo cylinder mounting plate are respectively and fixedly arranged between the rear vertical plate and the front vertical plate, a bottom servo cylinder penetrates through a through hole which is arranged on the frame bottom plate, a perpendicular bisector of the bottom servo cylinder mounting plate, a perpendicular bisector of the left servo cylinder mounting plate and a perpendicular bisector of the right servo cylinder mounting plate are mutually arranged at an angle of 120 degrees in space, a bottom servo cylinder is arranged on the bottom servo cylinder mounting plate, a left servo cylinder is arranged on the left servo cylinder mounting plate, and a right servo cylinder mounting plate, the device is provided with a right servo cylinder, a bottom centering roller is connected to an inner side extension rod connected with a piston of the bottom servo cylinder, a left centering roller is connected to an inner side extension rod connected with the piston of the left servo cylinder, a right centering roller is connected to an inner side extension rod connected with the piston of the right servo cylinder, a top rod is arranged among the bottom centering roller, the left centering roller and the right centering roller, a capillary tube is arranged on the top rod, and the lower end of the bottom servo cylinder is arranged below a bottom plate of a rack after penetrating through the bottom servo cylinder and penetrating through a through hole; a bottom turbine speed reducer is connected to the outer side extension rod connected with the piston of the bottom servo cylinder, a bottom hydraulic motor is connected to the bottom turbine speed reducer, a left turbine speed reducer is connected to the outer side extension rod connected with the piston of the left servo cylinder, a left hydraulic motor is connected to the left turbine speed reducer, a right turbine speed reducer is connected to the outer side extension rod connected with the piston of the right servo cylinder, and a right hydraulic motor is connected to the right turbine speed reducer; the bottom servo cylinder, the left servo cylinder and the right servo cylinder are communicated with a hydraulic system.
Splines are arranged at the outer end part of an outer side extension rod connected with a piston of a bottom servo cylinder, at the outer end part of an outer side extension rod connected with a piston of a left servo cylinder and at the outer end part of an outer side extension rod connected with a piston of a right servo cylinder, hollow output shafts are arranged on a bottom turbine speed reducer, a left turbine speed reducer and a right turbine speed reducer, and the outer end of the outer side extension rod connected with the piston is mechanically connected with the hollow output shafts through the splines; the roller surface of the bottom centering roller, the roller surface of the left centering roller and the roller surface of the right centering roller are all curved surfaces which are inwards concave back.
The outer side extension rod is provided with a position sensor probe insertion hole, the outer side end of the outer side extension rod is connected with a position sensor, a sensor probe rod of the position sensor is arranged in the position sensor probe insertion hole, and the position sensor is electrically connected with the hydraulic system.
A positioning adjustment method of a three-roller centering device with high-precision positioning is characterized by comprising the following steps:
firstly, respectively determining a feeding angle and a rolling angle formed between a bottom centering roller, a left centering roller, a right centering roller and a hollow billet according to the outer diameter of the hollow billet to be rolled, respectively rotating pistons in the three centering rollers through a bottom hydraulic motor, a left hydraulic motor and a right hydraulic motor, and enabling the centering rollers and an ejector rod to form envelope line contact on the circumference in the hollow billet rolling process;
secondly, injecting hydraulic oil into the three servo cylinders through a hydraulic system, driving three centering rollers to synchronously clamp the ejector rod by a piston in each servo cylinder, and finishing the stable positioning of the ejector rod during punching;
thirdly, when the rolled capillary tube rotates to the clamping position of the three centering rollers along the ejector rod, the three centering rollers are controlled to synchronously lift outwards for a certain distance through a hydraulic system, so that the capillary tube passes through, and the limitation to the capillary tube is formed;
and fourthly, after the capillary tube is rolled, respectively adjusting the central axis of the bottom centering roller, the central axis of the left centering roller and the central axis of the right centering roller to the positions vertical to the central axis of the ejector rod through the bottom hydraulic motor, the left hydraulic motor and the right hydraulic motor, so that the bottom centering roller, the left centering roller and the right centering roller form a retraction conveying roller way of the ejector rod and the capillary tube.
The invention has simple structure, saves a synchronous link mechanism of three rollers, improves the positioning precision of the centering roller by the servo cylinder, realizes enveloping contact with the ejector rod and the capillary tube by adopting an arc-shaped roller surface with an envelope line because the angles of the three rollers are all adjustable, and improves the stability of the ejector rod by real-time angle adjustment in the process of embracing the ejector rod and the capillary tube; the size of the annular space for penetrating the pipe can be adjusted in real time due to the fact that the servo cylinder is adopted for driving, the setting value of the annular space is enlarged before the pipe head arrives, and the annular space is reduced under the control of the servo cylinder after the pipe head passes through, so that the guiding stability of the capillary pipe is improved, and the wall thickness uniformity of the capillary pipe is further improved; meanwhile, the lower roller of the three rollers can realize the function of one roller for multiple purposes, the push rod is stabilized in the rolling process, the capillary is stabilized, and the push rod is changed into a supporting roller way for use through the rotation angle in the retraction process after steel throwing.
Drawings
FIG. 1 is a schematic structural view of the present invention;
FIG. 2 is a schematic structural view of a three-roll centering device frame of the present invention;
FIG. 3 is a schematic view of the present invention with three centering rollers abutting on the mandrel 16;
FIG. 4 is a schematic view of the present invention with three centering rollers abutting the capillary 26;
FIG. 5 is a schematic diagram of the envelope formed by the abutting connection of three centering rollers with the capillary 26 according to the present invention;
FIG. 6 is a view showing the fitting relationship between the hydraulic cylinder of the present invention and the hollow output shaft 29 of the turbine speed reducer;
fig. 7 is a schematic structural view of the centering rollers constituting the jack 16 and the retraction roller table of the capillary 26.
Detailed Description
The invention is described in detail below with reference to the accompanying drawings:
a three-roller centering device with high-precision positioning comprises a hydraulic system and a frame bottom plate 1, wherein a rear vertical plate 2 and a front vertical plate 4 are fixedly arranged on the frame bottom plate 1 in parallel, a rear vertical plate U-shaped groove 3 is arranged at the top end of the rear vertical plate 2, a front vertical plate U-shaped groove 5 is arranged at the top end of the front vertical plate 4, the rear vertical plate U-shaped groove 3 and the front vertical plate U-shaped groove 5 are correspondingly arranged, a bottom servo cylinder mounting plate 7, a left servo cylinder mounting plate 8 and a right servo cylinder mounting plate 9 are respectively and fixedly arranged between the rear vertical plate 2 and the front vertical plate 4, a bottom servo cylinder passing through hole 6 is arranged on the frame bottom plate 1, a perpendicular bisector of the bottom servo cylinder mounting plate 7, a perpendicular bisector of the left servo cylinder mounting plate 8 and a perpendicular bisector of the right servo cylinder mounting plate 9 mutually form an angle of 120 degrees in space, a bottom servo cylinder 10 is arranged on the bottom servo cylinder mounting plate 7, a left servo cylinder 11 is arranged on the left servo cylinder mounting plate 8, a right servo cylinder 12 is arranged on the right servo cylinder mounting plate 9, a bottom centering roller 13 is connected to an inner side extension bar connected with a piston of the bottom servo cylinder 10, a left centering roller 14 is connected to the inner side extension bar connected with the piston of the left servo cylinder 11, a right centering roller 15 is connected to the inner side extension bar connected with the piston of the right servo cylinder 12, a top rod 16 is arranged among the bottom centering roller 13, the left centering roller 14 and the right centering roller 15, the top rod 16 sequentially penetrates through the rear vertical plate U-shaped groove 3 and the front vertical plate U-shaped groove 5, a capillary 26 is arranged on the top rod 16, and the lower end of the bottom servo cylinder 10 is arranged below the rack bottom plate 1 after penetrating through the bottom servo cylinder through the through hole 6; a bottom turbine reducer 18 is connected to an outer side extension rod connected to the piston of the bottom servo cylinder 10, a bottom hydraulic motor 17 is connected to the bottom turbine reducer 18, a left turbine reducer 21 is connected to an outer side extension rod connected to the piston of the left servo cylinder 11, a left hydraulic motor 20 is connected to the left turbine reducer 21, a right turbine reducer 24 is connected to an outer side extension rod connected to the piston of the right servo cylinder 12, and a right hydraulic motor 23 is connected to the right turbine reducer 24; the bottom servo cylinder 10, the left servo cylinder 11 and the right servo cylinder 12 are communicated with a hydraulic system; the three servo cylinders are hydraulic cylinders.
Splines 28 are arranged at the outer end part of an outer side extension rod 27 connected with the piston of the bottom servo cylinder 10, the outer end part of an outer side extension rod connected with the piston of the left servo cylinder 11 and the outer end part of an outer side extension rod connected with the piston of the right servo cylinder 12, hollow output shafts 29 are arranged on the bottom turbine speed reducer 18, the left turbine speed reducer 21 and the right turbine speed reducer 24, and the outer ends of the outer side extension rods connected with the pistons are mechanically connected with the hollow output shafts 29 through the splines 28; the roller surface of the bottom centering roller 13, the roller surface of the left centering roller 14 and the roller surface of the right centering roller 15 are all curved surfaces which are inwards concave.
The outside extension rod 27 is provided with a position sensor probe insertion hole 22, the outside end of the outside extension rod 27 is connected with a position sensor 19, a sensor probe 25 of the position sensor 19 is arranged in the position sensor probe insertion hole 22, and the position sensor 19 is electrically connected with a hydraulic system.
A positioning adjustment method of a three-roller centering device with high-precision positioning is characterized by comprising the following steps:
firstly, respectively determining a feeding angle and a rolling angle formed between a bottom centering roller 13, a left centering roller 14, a right centering roller 15 and a hollow billet 26 according to the outer diameter of the hollow billet 26 to be rolled, and respectively rotating pistons in the three centering rollers through a bottom hydraulic motor 17, a left hydraulic motor 20 and a right hydraulic motor 23, so that the centering rollers and a mandril 16 form envelope line contact on the circumference in the hollow billet rolling process;
secondly, respectively injecting hydraulic oil into the three servo cylinders through an oil inlet 31 of an upper cavity of the cylinder body and an oil inlet 32 of a lower cavity of the cylinder body by a hydraulic system, driving three centering rollers to synchronously clamp the ejector rod 16 by a piston 30 in each servo cylinder, and finishing the stable positioning of the ejector rod 16 during punching;
thirdly, when the rolled capillary tube rotates to the clamping position of the three centering rollers along the mandril 16, the three centering rollers are controlled to synchronously lift outwards for a certain distance through a hydraulic system, so that the capillary tube 26 passes through, and the limit to the capillary tube 26 is formed;
and fourthly, after the capillary tube is rolled, respectively adjusting the central axis of the bottom centering roller 13, the central axis of the left centering roller 14 and the central axis of the right centering roller 15 to the position vertical to the central axis of the ejector rod 16 through the bottom hydraulic motor 17, the left hydraulic motor 20 and the right hydraulic motor 23, so that the bottom centering roller 13, the left centering roller 14 and the right centering roller 15 form a retraction conveying roller way of the ejector rod 16 and the capillary tube 26.

Claims (3)

1. A three-roller centering device with high-precision positioning comprises a hydraulic system and a frame bottom plate (1), wherein a rear vertical plate (2) and a front vertical plate (4) are fixedly arranged on the frame bottom plate (1) in parallel, a rear vertical plate U-shaped groove (3) is arranged at the top end of the rear vertical plate (2), a front vertical plate U-shaped groove (5) is arranged at the top end of the front vertical plate (4), the rear vertical plate U-shaped groove (3) and the front vertical plate U-shaped groove (5) are correspondingly arranged, a bottom servo cylinder mounting plate (7), a left servo cylinder mounting plate (8) and a right servo cylinder mounting plate (9) are respectively and fixedly arranged between the rear vertical plate (2) and the front vertical plate (4), a bottom servo cylinder penetrates through hole (6), a perpendicular bisector of the bottom servo cylinder mounting plate (7), a perpendicular bisector of the left servo cylinder mounting plate (8) and a perpendicular bisector of the right servo cylinder mounting plate (9) are arranged on the frame bottom plate (1), spatially forming an angle of 120 degrees with each other, characterized in that a bottom servo cylinder (10) is provided on a bottom servo cylinder mounting plate (7), a left servo cylinder (11) is provided on a left servo cylinder mounting plate (8), a right servo cylinder (12) is provided on a right servo cylinder mounting plate (9), a bottom centering roller (13) is connected to an inner side extension bar connected to a piston of the bottom servo cylinder (10), a left centering roller (14) is connected to the inner side extension bar connected to the piston of the left servo cylinder (11), a right centering roller (15) is connected to the inner side extension bar connected to the piston of the right servo cylinder (12), a top bar (16) is provided between the bottom centering roller (13), the left centering roller (14) and the right centering roller (15), a capillary tube (26) is provided on the top bar (16), and the lower end of the bottom servo cylinder (10), the servo cylinder penetrates through the bottom servo cylinder and penetrates through the through hole (6), and then the servo cylinder is arranged below the rack bottom plate (1); a bottom turbine speed reducer (18) is connected to an outer side extension rod connected with a piston of the bottom servo cylinder (10), a bottom hydraulic motor (17) is connected to the bottom turbine speed reducer (18), a left turbine speed reducer (21) is connected to the outer side extension rod connected with the piston of the left servo cylinder (11), a left hydraulic motor (20) is connected to the left turbine speed reducer (21), a right turbine speed reducer (24) is connected to the outer side extension rod connected with the piston of the right servo cylinder (12), and a right hydraulic motor (23) is connected to the right turbine speed reducer (24); the bottom servo cylinder (10), the left servo cylinder (11) and the right servo cylinder (12) are communicated with a hydraulic system.
2. The three-roller centering device with high precision positioning according to claim 1, characterized in that splines (28) are arranged at the outer end of an outer extension bar (27) connected with the piston of the bottom servo cylinder (10), at the outer end of an outer extension bar connected with the piston of the left servo cylinder (11) and at the outer end of an outer extension bar connected with the piston of the right servo cylinder (12), hollow output shafts (29) are arranged on the bottom turbine reducer (18), the left turbine reducer (21) and the right turbine reducer (24), and the outer ends of the outer extension bars connected with the pistons are mechanically connected with the hollow output shafts (29) through the splines (28); the roller surface of the bottom centering roller (13), the roller surface of the left centering roller (14) and the roller surface of the right centering roller (15) are all curved surfaces which are inwards concave back.
3. A high-precision positioning three-roller centering device according to claim 2, characterized in that a position sensor probe insertion hole (22) is provided on the outside extension bar (27), a position sensor (19) is connected to the outside end of the outside extension bar (27), a sensor probe (25) of the position sensor (19) is provided in the position sensor probe insertion hole (22), and the position sensor (19) is electrically connected with a hydraulic system.
CN202023031001.2U 2020-12-16 2020-12-16 Three-roller centering device with high-precision positioning function Active CN214078476U (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202023031001.2U CN214078476U (en) 2020-12-16 2020-12-16 Three-roller centering device with high-precision positioning function

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202023031001.2U CN214078476U (en) 2020-12-16 2020-12-16 Three-roller centering device with high-precision positioning function

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112496042A (en) * 2020-12-16 2021-03-16 太原通泽重工有限公司 Three-roller centering device with high-precision positioning and positioning adjustment method thereof

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112496042A (en) * 2020-12-16 2021-03-16 太原通泽重工有限公司 Three-roller centering device with high-precision positioning and positioning adjustment method thereof

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