A pipe end blanking control mechanism and coating method for a steel pipe curtain coating machine

Abstract

A pipe end blanking control mechanism for a steel pipe curtain spreading and coating machine includes a hopper mechanism (10), a gap control mechanism (20), and a width control mechanism (30). The gap control mechanism (20) forms a material drop gap (14) for adjusting the material drop width W of the material drop gap (14). 隙 The gap control mechanism (20) includes a fixed cam roller (21) and a rotatably mounted movable cam roller (22), forming a material drop gap (14) between the fixed cam roller (21) and the movable cam roller (22); the width control mechanism (30) simultaneously abuts against the fixed cam roller (21) and the movable cam roller (22) of the gap control mechanism (20), and moves along the material drop gap (14) in the same direction and at the same speed as the steel pipe to control the material drop width L of the material drop gap (14). 落 The tube end blanking control mechanism, in conjunction with the suction control mechanism and the amplitude control mechanism, allows the width and length of the material drop gap to be adjusted independently, automatically achieving tube end blanking.

Description

Technical Field

[0001] This invention relates to the field of steel pipe curtain coating, specifically to a pipe end blanking control mechanism and coating method for a steel pipe curtain coating machine. Background Technology

[0002] The curtain-type dispersion coating method is a common method for applying solvent-free solid powder coatings to pipes for corrosion protection. Heated steel pipes are conveyed via rotating rollers, moving forward through the coating zone to obtain the outer coating. Since 12-meter-long steel pipes are typically manufactured in sections and then joined at the pipe ends to form a finished pipe, a fixed length of 10-15 cm welding area must be left at the pipe ends, commonly known as "pipe end blanking." If this "pipe end blanking" is not considered during coating, the fixed length welding area must be ground out at the pipe ends later, which is time-consuming and labor-intensive.

[0003] Existing technologies typically employ pipe end capping or wrapping with protective tape to leave blank areas. The materials used must be heat-resistant, hence the use of metal caps or rubber tape. For example, BAYOU PERMA PIPE CANADA LTD discloses a method for coating threaded cast pipes (Publication No.: US2015300536A1, Publication Date: October 22, 2015). This method uses a nut connector 60, which includes opposing threaded first connecting portion 60A and unthreaded second connecting portion 60B. The threaded end 10A of the first steel pipe 10 is screwed into the first connecting portion 60A of the nut connector 60, and the other end 10B is wrapped with high-temperature protective tape 50 and inserted into the second connecting portion 60B of the nut connector 60 of the second steel pipe 10 and bonded. Multiple steel pipes 10 connected end-to-end enter the powder application area 42 of the coating line for coating. The nut connector 60 and the high-temperature protective tape 50 protect the threaded ends 10A and 10B of the steel pipes from being coated. Similarly, HIT KOGYO Co., Ltd. of Japan disclosed a method for leaving blank ends on steel pipes (Publication No.: JP3142507B2, Publication Date: March 7, 2001). In this method, the end of the steel pipe 6 is covered by a specified length to form an insertion part 8. The insertion part 8 is inserted into a heat-resistant rubber cover cap 11. The cover cap 11 has a forming part 12 and a press-fit part 13 arranged sequentially on its inner diameter. The forming part 12 is used to form a coating bevel, and the press-fit part 13 is liquid-sealed and circumferentially pressed against the outer circumference of the steel pipe. The disadvantage of this method is that, to leave blank ends on the pipes, at least 2-3 sets of caps are required for each specification of steel pipe. Since the caps need to be cleaned and reused after each use, and reheating is required for reuse, this is very troublesome and costly.

[0004] Existing technologies also include improvements to the spray head. NORDSON CORP in the United States disclosed a spraying method for steel pipes with threaded ends (Publication No.: US4986210A, Publication Date: January 22, 1991). An air nozzle 80 is clamped and fixed to the spray head 20 and positioned behind the spray head 20, referencing the direction of spray head movement. When spraying the threaded end, the front spray head 20 ejects resin particles 13, followed by high-pressure air blown from the air nozzle 80 to remove the resin particles 13, thus preventing contamination of the threaded section. The disadvantages of this method are: it results in additional waste of resin particles 13, air pump energy, and electrical energy; and resin particles that are not blown away by the high-pressure air may form coating spots on the threaded section.

[0005] Therefore, there is an urgent need in this field for a pipe end blanking control mechanism for a steel pipe curtain coating machine that can continuously coat steel pipes while leaving blanks at both ends, without the need for additional shielding caps. This is a pressing problem that needs to be solved in the field of steel pipe coating. Summary of the Invention

[0006] In view of the defects existing in the prior art, the purpose of this invention is to provide a pipe end blanking control mechanism and coating method for a steel pipe curtain coating machine, which can solve the problem of continuous coating of steel pipes while keeping the first and last pipe ends blank without the need to add a shielding pipe cap, thus solving the technical problem in the field of steel pipe coating.

[0007] The objective of this invention is achieved by providing a pipe end blanking control mechanism for a steel pipe curtain coating machine, comprising:

[0008] The hopper mechanism includes a hopper body, with a particle inlet at the top and a discharge port at the bottom extending along the straight travel direction of the steel pipe. The hopper mechanism is used to contain resin particles to be coated and to form a particle curtain along the travel direction of the steel pipe through the discharge port, which falls onto the outer periphery of the traveling steel pipe.

[0009] The gap control mechanism is located below the material discharge port and forms a material discharge gap, used to adjust the material discharge width W of the gap. 隙 The gap control mechanism includes a fixed cam roller and a moving cam roller arranged parallel to each other on both sides of the material discharge port. The fixed cam roller is fixedly arranged, and the moving cam roller is rotatably arranged, forming a material discharge gap between the fixed cam roller and the moving cam roller.

[0010] The amplitude control mechanism simultaneously abuts against the fixed cam roller and the moving cam roller of the gap control mechanism, and moves along the blanking gap at the same direction and speed as the steel pipe to control the blanking width L of the blanking gap. 落 .

[0011] Furthermore, the cross-sections of the fixed cam roller and the moving cam roller include a fixed roller contacting surface and a fixed roller circumferential surface, and the moving cam roller includes a moving roller contacting surface and a moving roller circumferential surface. The fixed roller contacting surface is fixedly connected to one side of the discharge port, and the moving roller contacting surface is attached to the other side of the discharge port. The fixed roller circumferential surface and the moving roller circumferential surface simultaneously abut against the amplitude control mechanism.

[0012] Furthermore, the fixed cam roller includes a fixed roller discharge guide surface, which is substantially perpendicular to and aligned with the left wall of the discharge port. The moving cam roller includes a moving roller contact surface, and the gap between the leading edge of the moving roller contact surface and the fixed roller discharge guide surface forms the discharge gap.

[0013] Furthermore, the hopper body is fixedly connected to the gap-blocking rubber on both sides of the discharge port, the fixed roller is fixedly connected to the hopper body through the gap-blocking rubber, and the moving roller rotates to abut against the gap-blocking rubber.

[0014] Furthermore, the width control mechanism includes a gap-covering roller and two support positioning rollers. The two support positioning rollers are symmetrically fixed on both sides of the material drop gap, and the gap-covering roller simultaneously abuts against and slides between the fixed cam roller, the moving cam roller and the support positioning rollers.

[0015] Furthermore, the gap-closing roller includes a left gap-closing roller and a right gap-closing roller. The left gap-closing roller is slidably provided on the left side wall of the hopper body along the traveling direction of the steel pipe, and the right gap-closing roller is slidably provided on the right side wall along the traveling direction of the steel pipe. The left gap-closing roller and the right gap-closing roller are respectively driven by a direct-moving mechanism. The right gap-closing roller is driven by the direct-moving mechanism to control the rightmost coating boundary of the material drop gap, and the left gap-closing roller is driven by the direct-moving mechanism to control the leftmost coating boundary of the material drop gap.

[0016] Furthermore, the linear movement mechanism includes a lead screw, a nut, and a linear movement motor. Fixed frame plates are fixedly installed on both sides of the hopper body. Each fixed frame plate includes a side fixed plate fixedly connected to the side wall of the hopper body. The linear movement motor is fixedly mounted on the top fixed plate of the fixed frame plate. The lead screw is rotatably mounted on the two side fixed plates of the fixed frame plate. A slider is slidably provided on the top plate of the fixed frame plate. The slider is simultaneously fixedly connected to the nut and the gap-covering roller. The nut is screwed into the lead screw. The lead screw is powered by the conveyor belt and connected to the linear movement motor.

[0017] Furthermore, the tube end blanking control mechanism has a tube end blanking mode and a full-length coating mode; the leftmost end of the material drop gap (14) corresponds to the leftmost coating boundary P. 左 The rightmost point corresponds to the leftmost boundary P. 右 ; Pipe end blanking mode, corresponding blanking initialization: the right end of the left blinding roller and the left end of the right blinding roller are aligned with the leftmost coating boundary P. 左 Left seam length L 左 =L 隙 Right seam length L 右 =0, while simultaneously satisfying the material feeding gap being the preset gap W. 预 L 隙For the entire length of the material feeding gap; in the continuous coating mode, the corresponding continuous coating initialization is: the right end of the left gap-masking roller is aligned with the leftmost coating boundary P. 左 The left end of the right slit roller is aligned with the rightmost coating boundary P. 右 Left seam length L 左 =L 隙 Right seam length L 右 =L 隙 At the same time, it meets the preset gap W of the material feeding gap. 预 L 隙 To ensure the full length of the material cut-out gap, the left coating seam length is L. 左 The distance P from the right end of the left slit roller to the rightmost coating boundary. 右 The length of the right seam is L. 右 The distance P from the left end of the right slit roller to the leftmost coating boundary. 左 The length.

[0018] A pipe-end white-out control mechanism for the steel pipe curtain coating machine includes the following steps:

[0019] S1 front blank space

[0020] The steel pipe rotates and moves in a straight line along the direction of travel until the front end of the steel pipe aligns with the leftmost coating boundary P. 左 When the blank length L is added, the right seam roller is started and follows the steel pipe at the same speed along the direction of travel until the left end of the right seam roller moves straight to align with the rightmost coating boundary and stops; at the same time, the length L of the left coating seam is checked and verified every time interval t. 左 =L 隙 ;

[0021] S2 Mid-section Coating

[0022] The steel pipe continues to rotate and move straight along the direction of travel, while the length L of the left coating seam is checked and inspected every time interval t. 左 =L 隙 Right seam length L 右 =L 隙 Continue until the rear end of the steel pipe is aligned with the leftmost paint boundary;

[0023] S3 backend blank space

[0024] The steel pipe continues to rotate and move straight along the direction of travel. When the rear end of the steel pipe is at the leftmost paint boundary P... 左 During alignment, start the left blocking roller and follow the steel pipe at the same speed along the direction of travel until the left end of the left blocking roller moves straight to the rightmost coating boundary P. 右 Alignment stops, and simultaneously, the length L of the right-side coating seam is checked and verified every time interval t. 右 =L 隙 ;

[0025] S4 blank initialization

[0026] Simultaneously, the left and right seam-blocking rollers move at the same speed in the opposite direction of the steel pipe's travel direction until the right end of the left seam-blocking roller and the left end of the right seam-blocking roller are aligned with the leftmost coating boundary, i.e., the right coating seam length L. 右 =0, left seam length L 左 =L 隙 Rotate the moving cam roller so that W 隙 =W 预 .

[0027] The following steps are included before step S1:

[0028] S0 Verification and White Space Initialization

[0029] a double alignment of the leftmost paint boundary P 左

[0030] Check if the right end of the left squeegee roller and the left end of the right squeegee roller have moved to the leftmost coating boundary. If not, move the left squeegee roller or its right end to align with the leftmost coating boundary P. 左 Left seam length L 左 =L 隙 Alternatively, if this is not satisfied, move the right seam roller so that its left end aligns with the leftmost coating boundary, with the right seam length L. 右 =0;

[0031] b. The material feeding gap is the preset gap W. 预

[0032] Detecting material drop gap W 隙 Is it equal to W? 预 That is, to determine W 隙 -W 预 ≤E 预 Does it meet the requirements? If not, rotate the moving cam roller so that W... 隙 -W 预 ≤E 预 E 预 This is the preset error threshold.

[0033] Compared with existing technologies, the tube end blanking control mechanism and coating method of the steel pipe curtain spreading coating machine, through the combination of suction control mechanism and amplitude control mechanism, make the width of the material drop gap adjustable and the length of the material drop gap adjustable. It can automatically achieve tube end blanking without the need to set an additional shielding cap on the tube end, improve coating efficiency, and automatically switch between tube end blanking mode and full-length coating mode. Attached Figure Description

[0034] Figure 1 This is a main sectional view of Embodiment 1 of the pipe end blanking control mechanism of the steel pipe curtain spreading and coating machine of the present invention;

[0035] Figure 2This is Embodiment 1 of a pipe end blanking control mechanism for a steel pipe curtain coating machine according to the present invention. Figure 1 AA section view;

[0036] Figure 3 This is Embodiment 1 of a pipe end blanking control mechanism for a steel pipe curtain coating machine according to the present invention. Figure 1 AA cross-sectional view (another implementation example);

[0037] Figure 4 This is Embodiment 1 of a pipe end blanking control mechanism for a steel pipe curtain coating machine according to the present invention. Figure 1 BB cross-sectional view (gap width W1).

[0038] Figure 5 This is Embodiment 1 of a pipe end blanking control mechanism for a steel pipe curtain coating machine according to the present invention. Figure 1 BB cross-sectional view (gap width 0);

[0039] Figure 6 This is a schematic diagram of the gap control mechanism in Embodiment 1 of the pipe end blanking control mechanism of the steel pipe curtain spreading coating machine of the present invention.

[0040] Figure 7 This is a C-direction view of an embodiment 1 of the pipe end blanking control mechanism of a steel pipe curtain spreading and coating machine according to the present invention.

[0041] Figure 8 This is a D-view of an embodiment 1 of the pipe end blanking control mechanism of a steel pipe curtain spreading and coating machine according to the present invention.

[0042] Figure 9 This is a schematic diagram of the coating state of the front end blanking in Embodiment 1 of the pipe end blanking control mechanism of the steel pipe curtain spreading coating machine of the present invention.

[0043] Figure 10 This is a schematic diagram of the coating state of the middle section coating in Embodiment 1 of the pipe end blanking control mechanism of the steel pipe curtain spreading coating machine of the present invention.

[0044] Figure 11 This is a schematic diagram of the coating state of the rear end blanking in Embodiment 1 of the pipe end blanking control mechanism of the steel pipe curtain spreading coating machine of the present invention.

[0045] The reference numerals in the above figure:

[0046] 10 Hopper mechanism, 11 Hopper body, 12 Particle inlet, 13 Discharge port, 14 Discharge gap, 15 Guide plate

[0047] 20 Clearance control mechanism, 21 Fixed cam roller, 22 Moving cam roller, 23 Leading edge, 24 Clearance control cylinder, 25 Clearance plugging rubber, 26 Torque applicator, 27 Driven gear, 28 Driving gear

[0048] 21.1 Fixed feeding hopper surface, 21.2 Fixed roller feeding guide surface, 21.3 Fixed roller circumferential surface, 22.1 Moving feeding hopper surface, 22.2 Moving roller bonding surface, 22.3 Moving roller circumferential surface

[0049] 30. Width control mechanism; 31. Seam-closing roller; 32. Support and positioning roller; 31.1. Left seam-closing roller; 31.2. Right seam-closing roller.

[0050] 40. Linear movement mechanism; 41. Lead screw; 42. Nut; 43. Linear movement motor; 44. Fixed frame plate; 45. Slide groove; 46. Slider; 47. Sliding chuck.

[0051] 50 Position detection, 51 Left coating sensing, 52 Right coating sensing, 53 First reflective part, 54 Second reflective part

[0052] P is the steel pipe to be coated, P 左 Leftmost boundary, P 右 The rightmost boundary, L 隙 Blanking length, W 隙 Blanking width, W 预 Preset gap, N blank area Detailed Implementation

[0053] The embodiments of the present invention will be described in detail below with reference to the accompanying drawings, but are not intended to limit the scope of the present invention.

[0054] Example 1

[0055] A pipe end blanking control mechanism for a steel pipe curtain coating machine, comprising:

[0056] The hopper mechanism 10 includes a hopper body 11 with a V-shaped cross-section. The top of the hopper body 11 has a particle inlet 12, and the bottom of the hopper body 11 has a discharge port 13 extending along the straight travel direction of the steel pipe. The hopper mechanism 10 is used to contain the resin particles to be coated, and through the discharge port 13, forms a particle curtain along the travel direction of the steel pipe, which falls onto the outer periphery of the traveling steel pipe.

[0057] Gap control mechanism 20 is located below the material discharge port 13 and forms a material discharge gap 14, used to adjust the material discharge width W of the material discharge gap 14. 隙The gap increases linearly from 0 to W1. The gap control mechanism 20 includes a fixed cam roller 21 and a movable cam roller 22 located on both sides of the discharge port 13, extending along the length of the discharge port 13. The cross-sections of the fixed cam roller and the movable cam roller are fan-shaped, and the central angle β of the fan shape is preferably 110°≤β≤150°. A discharge gap 14 is formed between the fixed cam roller 21 and the movable cam roller 22, and the discharge length L of the discharge gap 14 is... 隙 The length of the material discharge port 13 is specified. The fixed cam roller 21 is axially fixed to the fixed frame plate 44 at both ends by bolts. Preferably, the fixed frame plate 44 includes an arc-shaped elongated hole, and the bolts are fixed at different positions within the arc-shaped elongated hole to adjust the fixed roller discharge guide surface 21.2 of the fixed cam roller 21 to be approximately vertical. The angle between the fixed roller discharge guide surface 21.2 and the vertical plane can be between 0 and 5 degrees. The movable cam roller 22 is rotatably mounted on the side fixed plate 23 at both ends. The side fixed plate 23 is equipped with a clearance control cylinder 24. The output shaft of the clearance control cylinder 24 is eccentrically fixed to the movable cam roller 22 via a torque applicator 26. The fixed end of the clearance control cylinder 24 is fixedly connected to the top plate of the fixed frame plate via a rotating support. The torque applicator 26 has a rotation hole 26.1 and a torque application hole 26.2 at both ends, with the torque application hole being a lever arm S away from the rotation hole. The telescopic piston end of the clearance-controlled cylinder 24 is hinged to the torque application hole 26.2 via a pin, and the rotating hole 26.1 is coaxially and fixedly connected to the moving cam roller 22. The length of the lever arm S determines the displacement length of the cylinder piston required to rotate one degree.

[0058] To more precisely control the rotation angle, a driven gear 27 is fixed to the end of the moving cam roller 22. A driving gear 28 meshes with the driven gear 27. The driving gear 28 is fixed to the output shaft of the adjusting motor 29, which is fixed to the side mounting plate of the mounting frame 44. Through the module design of the driven gear 27, each meshing tooth controls the rotation of the moving cam roller 22 by 0.1 degrees, thereby increasing the blanking width W. 隙 Control precision.

[0059] The principle of controlling the material discharge width W of the discharge gap 14 linearly increasing from 0 to W1 is as follows: The cross-section of the fixed cam roller 21 includes a fixed hopper surface 21.1, a fixed roller discharge guide surface 21.2, and a fixed roller circumferential surface 21.3. The discharge port 13 of the hopper body 11 has gap-blocking rubber 25 fixed on the left and right walls along the steel pipe travel direction. The fixed hopper surface 21.1 is tightly attached to the left wall through the gap-blocking rubber 25. When the fixed roller discharge guide surface 21.2 is approximately perpendicular to and aligned with the left wall of the discharge port 13, the fixed roller circumferential surface 21.3 abuts against the gap-blocking roller 31 below. The cross-section of the moving cam roller 22 includes a moving hopper surface 22.1, a moving roller contact surface 22.2, and a moving roller circumferential surface 22.3. The gap-blocking rubber 25 of the moving roller hopper surface 22.1, which is tightly attached to the right wall of the hopper body 11, is rotatably set below the discharge port 13. The gap between the leading edge 23 of the moving roller contact surface 22.2 and the material dropping guide surface 21.2 of the fixed roller forms the material dropping gap 14.

[0060] like Figure 6 As shown, the gap control motor 24 drives the moving cam roller 22 to rotate counterclockwise, and the material discharge gap 14 is the material discharge width W of the moving hopper surface 22.1 closely attached to the fixed roller material discharge guide surface 21.2. 隙 =0 gradually increases to the maximum material discharge gap W between the leading edge 23 of the moving roller contact surface 22.2 and the material discharge guide surface 21.2 of the stationary roller. 隙 =W 预 W 预 To preset the blanking width, W 预 =2mm-15mm. The moving roller contact surface 22.2 is a straight plane. The radius of the moving roller contact surface 22.2 is slightly smaller than the radius of the moving roller circumference. When the front edge 23 of the moving roller contact surface 22.2 is attached to the fixed roller discharge guide surface 21.2, the discharge gap W 隙 =0, the width of the moving roller contact surface 22.2 is at least 15mm, sufficient to close the discharge port 14. The moving cam roller 22 rotates counterclockwise, and the moving roller contact surface 22.2 tilts in the opposite direction, becoming a reverse slope relative to the discharge direction, greatly reducing the chance of adhering particles, so as to close the discharge gap W. 隙 =0 allows for better gap sealing. The width of the distance between the leading edge 23 of the moving roller contact surface 22.2 and the material guide surface 21.2 of the fixed roller is the material discharge gap W. 隙 At this time, the moving cam roller 22 rotates counterclockwise by an angle equal to the gap angle α, where 5°≤α≤25°.

[0061] Amplitude control mechanism 30 is located below and cooperates with gap control mechanism 20. Amplitude control mechanism 30 simultaneously abuts against fixed cam roller 21 and moving cam roller 22 of gap control mechanism 20, and moves at the same speed as steel pipe along the direction of blanking gap 14 to control the blanking width L of blanking gap 14. 落 The blanking gap 14 has a default blanking length L. 隙The so-called same-speed movement means that the spiral welded pipe moves at the same speed as it moves linearly along the direction of travel.

[0062] The control mechanism 30 includes a gap-blocking roller 31 and two support positioning rollers 32. The two support positioning rollers 32 are parallel and spaced apart directly below the gap 14 of the discharge port 13, allowing resin particles to fall between the support positioning rollers 32. The gap-blocking roller 31 simultaneously abuts against the two support positioning rollers and the fixed cam roller 21 and the movable cam roller 22 of the control mechanism 20. Specifically, the upper semicircular surface of the gap-blocking roller 31 simultaneously abuts against the fixed roller circumferential surface 21.3 of the fixed cam roller 21 and the movable roller circumferential surface 22.3 of the movable cam roller 22, and the lower semicircular surface simultaneously abuts against the roller circumferential surface of the support positioning roller 32. To reduce the static friction between the gap-blocking roller 31 and the four rollers, the gap-blocking roller 31 is preferably a metal tube or a thermoplastic resin tube.

[0063] The side fixing plate of the fixed frame plate 44 is provided with a mounting slot, and the shaft ends of the two support positioning rollers 32 are fixed in the mounting slot by bolts. The gap-blocking roller 31 is coupled to the linear movement mechanism 40. Driven by the linear movement mechanism 40, the gap-blocking roller 31 moves at the same speed between the gap control mechanism 20 and the support positioning rollers 32 along the length direction of the material drop gap 14. The length of the gap-blocking roller 31 is greater than or equal to the length of the material drop gap 14, that is, the gap-blocking roller 31 can completely block the entire length of the material drop gap 14, preventing material from falling. The leftmost end of the material drop gap 14 corresponds to the leftmost coating boundary P. 左 The rightmost end of the blanking gap 14 corresponds to the leftmost coating boundary P. 右 .

[0064] The gap-closing roller 31 includes a left gap-closing roller 31.1 and a right gap-closing roller 31.2. The left gap-closing roller 31.1 is provided on the left side wall of the hopper body 11 of the hopper mechanism 10 along the traveling direction of the steel pipe, and the right gap-closing roller 31.2 is provided on the right side wall. The left and right side walls of the hopper body 11 are respectively fixed with a linear movement mechanism 40 that drives and connects the left gap-closing roller 31.1 and the right gap-closing roller 31.2.

[0065] The linear movement mechanism 40 includes a lead screw 41, a nut 42, and a linear movement motor 43. The linear movement motor 43 is fixed to a fixed frame plate 44. The top plate of the fixed frame plate 44 has a groove 45. A sliding head 47 is provided on the top of the slider 46 connecting the nut 42 and the gap-covering roller 31, and the sliding head 47 is slidably positioned in the groove 45. A driven pulley is fixed to one end of the lead screw 41, and the output shaft of the linear movement motor 43 is fixed to a driving pulley. A power transmission belt is located between the driving and driven pulleys. The slider 46 is fixedly connected to the gap-covering roller 31 via a spring clip. The linear movement motor 43 drives the lead screw 41 to rotate, which in turn drives the nut 42 to move linearly along the lead screw. The nut 42 then drives the slider 46 and the gap-covering roller 31 to move at the same speed. The left fixed plate of the fixed frame plate 44 is fixedly connected to the hopper body 11, and the right fixed plate of the fixed frame plate 44 has a limit block to limit the maximum stroke of the gap-covering roller 31. The left side of the chute 45 defines the minimum stroke of the gap-covering roller 31.

[0066] It also includes a position detection 50, which includes a left coating sensor 51 and a right roller end sensor 52. The left roller end sensor 51 and the right roller end sensor 52 are laser rangefinders. The right end of the left slit roller 31.1 is provided with a first reflective part 53 on the radially outer side, and the left end of the right slit roller 31.2 is provided with a second reflective part 54 on the radially outer side. The left roller end sensor 51 is located on the side wall opposite the first reflective part 53. It is used to measure the length of the distance from the right end of the left slit roller to the unblocked material drop gap 14 on the side plate, which is called the left coating gap length L. 左 A right roller end sensor 52 is provided on the side wall opposite the second reflective part 54. It is used to measure the length of the distance from the roller end to the unobstructed material drop gap 14 on the opposite side plate, which is called the right coating gap length L. 右 For measuring the material drop gap 14, a gap sensor 55 is provided on the moving roller contact surface 22.2, aligned with the leading edge 23. The laser emitted from the gap sensor 55 illuminates the stationary roller material drop guide surface 21.2 and returns to obtain the width W of the material drop gap 14. 隙 .

[0067] The tube end blanking control mechanism has two modes: tube end blanking mode and full-length coating mode. In tube end blanking mode, the machine defaults to this mode upon power-up. The blanking initialization in tube end blanking mode is as follows: the right end of the left shim roller 31.1 and the left end of the right shim roller 31.2 are aligned with the leftmost coating boundary P. 左 Left seam length L 左 =L 隙 Right seam length L 右 =0, while simultaneously satisfying the material drop gap 14 as the preset gap W. 预 L 隙 This refers to the entire length of the material drop gap. In the continuous coating mode, the corresponding initialization is: the right end of the left gap-masking roller 31.1 is aligned with the leftmost coating boundary P. 左 The left end of the right gap-covering roller 31.2 is aligned with the rightmost coating boundary P.右 Left seam length L 左 =L 隙 Right seam length L 右 =L 隙 At the same time, the material feeding gap 14 is the preset gap W. 预 L 隙 The length of the left-hand seam is L, which is the length of the material cut gap 14. 左 The distance from the right end of the left gap-covering roller 31.1 to the rightmost coating boundary P 右 The length of the right seam is L. 右 The distance from the left end of the right slit roller 31.2 to the leftmost coating boundary P 左 The length.

[0068] A pipe end blanking coating method using the aforementioned pipe end blanking control mechanism.

[0069] When running in pipe end blank mode

[0070] S0 Verification and White Space Initialization

[0071] ① Double alignment of the leftmost boundary P 左

[0072] The amplitude control mechanism 30 is activated to detect whether the right end of the left gap-covering roller 31.1 has moved to the leftmost coating boundary P. 左 Check whether the left end of the right gap-covering roller 31.2 has moved to the leftmost coating boundary P. 左 If the conditions are not met, the linear movement mechanism 40 is activated to move the left gap-covering roller 31.1 so that its right end is aligned with the leftmost coating boundary P. 左 Left seam length L 左 =L 隙 Move the right gap-covering roller 31.2 so that its left end aligns with the leftmost coating boundary P. 左 Right seam length L 右 =0;

[0073] More preferably, the left gap-covering roller 31.1 and the right gap-covering roller 31.2 start simultaneously and move at the same speed.

[0074] ②The material feeding gap 14 is the preset gap W 预

[0075] The gap control mechanism 20 is activated, and the gap sensor 55 detects the gap of the moving cam roller and measures W. 隙 Material drop gap W 隙 Is it equal to W? 预 That is, to determine W 隙 -W 预 ≤E 预 Does it meet the requirements? (E) 预 The preset error threshold is used; if it is not met, the moving cam roller is rotated so that W... 隙 -W 预≤E 预 .

[0076] S1 front end flowing white

[0077] like Figure 7 As shown, steel pipe 2 rotates and moves in a straight line along the direction of travel. When the front end of the steel pipe aligns with the leftmost coating boundary P... 左 When subtracting the blank length L, start the right gap-covering roller 31.2 and follow the steel pipe 2 at the same speed along the traveling direction until the left end of the right gap-covering roller 31.2 moves straight to align with the rightmost coating boundary P. 右 Alignment stops; simultaneously, the length L of the left coating seam is checked and verified every interval t. 左 =L 隙 .

[0078] S2 Mid-section Coating

[0079] like Figure 8 As shown, steel pipe 2 continues to rotate and move straight along the direction of travel, while the length L of the left coating seam is checked and inspected every time interval t. 左 =L 隙 Right seam length L 右 =L 隙 Until the rear end of the steel pipe meets the leftmost paint boundary P 左 Alignment.

[0080] S3 backend blank space

[0081] like Figure 9 As shown, steel pipe 2 continues to rotate and move straight along the direction of travel. When the rear end of the steel pipe is perpendicular to the leftmost paint boundary P... 左 During alignment, start the left blocking roller 31.1 and follow the steel pipe 2 at the same speed along the direction of travel until the left end of the left blocking roller 31.1 moves straight to the rightmost coating boundary P. 右 Alignment stops, and simultaneously, the length L of the right-side coating seam is checked and verified every time interval t. 右 =L 隙 .

[0082] S4 blank initialization

[0083] Simultaneously activate the linear movement mechanism 40 of the left and right eccentric rollers 31.1 and 31.2, moving them at the same speed in the opposite direction of the steel pipe's travel direction until the right end of the left eccentric roller 31.1 and the left end of the right eccentric roller 31.2 are aligned with the leftmost coating boundary P. 左 That is, the length of the right-side seam is L. 右 =0, left seam length L 左 =L 隙 Rotate the moving cam roller so that W 隙 =W 预 .

[0084] More preferably, a brush is fixed above the end of the gap-covering roller, with the brush facing the contact surface 22.2 of the moving roller. When the last tube is coated and the blanking initialization is performed, the brush brushes the contact surface 22.2 of the moving roller of the gap-covering roller once, and the particles adhering to it are scraped off by the brush bristles. When shutting down, the material gap is zeroed, and the moving cam roller 22 is rotated clockwise until the contact surface 22.2 of the moving roller is in contact with the fixed roller material guide surface 21.2 of the fixed cam roller 21 to close the material discharge port 14.

[0085] The pipe end blanking control mechanism and coating method of the steel pipe curtain coating machine solve the technical problem of "achieving continuous coating of steel pipes while leaving blanks at both ends of the pipes" through the following technical means:

[0086] (1) The fixed cam roller cooperates with the moving cam roller, and the gap control mechanism 20 realizes the width adjustment of the material drop gap 14.

[0087] The distance between the fixed roller feeding guide surface 21.2 and the front edge 23 of the moving roller contact surface 22.2 forms the feeding gap 14. Rotating the moving cam roller 22 rotates the moving roller contact surface 22.2, thereby adjusting the feeding gap 14 from 0 to W. 隙 Linear change.

[0088] (2) The amplitude control mechanism 30, together with the gap control mechanism 20, realizes the length adjustment of the material drop gap 14.

[0089] The left and right shunting rollers 31.1 and 31.2 of the control mechanism 30 are simultaneously slidably positioned between the fixed cam roller 21, the moving cam roller 22, and the two supporting positioning rollers 32. During coating, the right shunting roller 31.2 follows the steel pipe at the same speed, thus blocking a blank length L at the right end of the steel pipe from coating. Similarly, the left shunting roller follows the steel pipe at the same speed, thus blocking a blank length L at the left end of the steel pipe from coating. Following at the same speed means moving linearly at the same speed; the shunting roller 31 does not rotate.

[0090] When following at the same speed, the fixed cam roller 21, the moving cam roller 22 and the two support positioning rollers 32 achieve the blocking and guiding positioning of the gap-covering roller 31 below the material drop gap. Therefore, the gap control mechanism 20 works in conjunction with the amplitude control mechanism 30 to complete this task.

[0091] Compared with the prior art, the tube end blanking control mechanism and coating method of the steel pipe curtain spreading coating machine, through the suction control mechanism 20 and the amplitude control mechanism 30, make the width of the material drop gap adjustable and the length of the material drop gap adjustable. It can automatically achieve tube end blanking without setting an additional shielding cap on the tube end, improve coating efficiency, and automatically switch between tube end blanking mode and full-length coating mode.

Claims

1. A pipe end blanking control mechanism for a steel pipe curtain coating machine, characterized in that, include The hopper mechanism (10) includes a hopper body (11), a particle inlet (12) at the top of the hopper body (11), and a discharge port (13) extending along the straight travel direction of the steel pipe at the bottom. The hopper mechanism (10) is used to contain the resin particles to be coated, and a particle curtain is formed along the travel direction of the steel pipe through the discharge port (13), which falls onto the outer periphery of the traveling steel pipe. The gap control mechanism (20) is located below the material discharge port (13) and forms a material discharge gap (14) for adjusting the material discharge width W of the material discharge gap (14). 隙 The gap control mechanism (20) includes a fixed cam roller (21) and a moving cam roller (22) arranged parallel to each other on both sides of the discharge port (13). The fixed cam roller (21) is fixedly arranged, and the moving cam roller (22) is rotatably arranged, forming a discharge gap (14) between the fixed cam roller (21) and the moving cam roller (22). The width control mechanism (30) includes a gap-blocking roller (31) located below the gap control mechanism (20). The gap-blocking roller (31) simultaneously abuts against the fixed cam roller (21) and the moving cam roller (22) of the gap control mechanism (20). The width control mechanism (30) moves along the material drop gap (14) in the same direction and at the same speed as the steel pipe to control the material drop width L of the material drop gap (14). 落 .

2. The pipe end blanking control mechanism of the steel pipe curtain coating machine as described in claim 1, characterized in that, The cross-section of the fixed cam roller includes a fixed roller hopper surface (21.1) and a fixed roller circumferential surface (21.3). The cross-section of the moving cam roller (22) includes a moving roller hopper surface (22.1) and a moving roller circumferential surface (22.3). The fixed roller hopper surface (21.1) is fixedly connected to one side of the discharge port (13), and the moving roller hopper surface is attached to the other side of the discharge port (13). The fixed roller circumferential surface (21.3) and the moving roller circumferential surface (22.3) simultaneously abut against the amplitude control mechanism (30).

3. The pipe end blanking control mechanism of the steel pipe curtain coating machine as described in claim 1, characterized in that, The cross-section of the fixed cam roller (21) also includes a fixed roller discharge guide surface (21.2), which is approximately perpendicular to and aligned with the left wall of the discharge port (13). The cross-section of the moving cam roller (22) also includes a moving roller contact surface (22.2), and the gap between the leading edge (23) of the moving roller contact surface (22.2) and the fixed roller discharge guide surface (21.2) forms the discharge gap (14).

4. The pipe end blanking control mechanism of the steel pipe curtain coating machine as described in any one of claims 1-3, characterized in that, The hopper body (11) is fixedly connected to the blocking rubber (25) on both sides of the discharge port (13). The fixed roller is fixedly connected to the hopper body (11) through the blocking rubber (25). The moving roller is rotated to abut against the blocking rubber (25).

5. The pipe end blanking control mechanism of the steel pipe curtain coating machine as described in any one of claims 1-3, characterized in that, The amplitude control mechanism (30) also includes two support positioning rollers (32), which are symmetrically fixed on both sides of the material drop gap (14). The gap-covering roller (31) simultaneously abuts and slides between the fixed cam roller (21), the moving cam roller (22) and the support positioning roller (32).

6. The pipe end blanking control mechanism of the steel pipe curtain coating machine as described in claim 4, characterized in that, The gap-closing roller (31) includes a left gap-closing roller (31.1) and a right gap-closing roller (31.2). The left gap-closing roller (31.1) is slidably provided on the left side wall of the hopper body (11) along the direction of the steel pipe travel, and the right gap-closing roller (31.2) is slidably provided on the right side wall along the direction of the steel pipe travel. The left gap-closing roller (31.1) and the right gap-closing roller (31.2) are respectively driven by the direct-moving mechanism (40). The right gap-closing roller (31.2) is driven by the direct-moving mechanism (40) to control the rightmost coating boundary (P) of the material drop gap (14). 右 The left gap-covering roller (31.1) is driven by the linear movement mechanism (40) to control the leftmost coating boundary (P) of the material drop gap (14). 左 ).

7. A pipe end blanking control mechanism for a steel pipe curtain coating machine as described in claim 6, characterized in that, The direct movement mechanism (40) includes a lead screw (41), a nut (42) and a motor (43). Fixed frame plates (44) are fixedly installed on both sides of the hopper body (11). The fixed frame plate (44) includes a side fixed plate that is fixedly connected to the side wall of the hopper body. The motor (43) is fixedly installed on the top fixed plate of the fixed frame plate. The lead screw (41) is rotatably installed on the two side fixed plates of the fixed frame plate. The top plate of the fixed frame plate is slidably provided with a slider (46). The slider (46) is simultaneously fixedly connected to the nut (42) and the gap-covering roller (31). The nut (42) is screwed to the lead screw (41). The lead screw (41) is powered by the motor (43) through the conveyor belt.

8. A pipe end blanking control mechanism for a steel pipe curtain coating machine as described in claim 6, characterized in that, The tube end blanking control mechanism has a tube end blanking mode and a full-length coating mode; the leftmost end of the material drop gap (14) corresponds to the leftmost coating boundary (P). 左 The rightmost end corresponds to the rightmost shading boundary (P). 右 ); Pipe end blanking mode, corresponding blanking initialization: the right end of the left blinding roller (31.1) and the left end of the right blinding roller (31.2) are aligned with the leftmost coating boundary (P 左 ), left seam length L 左 =L 隙 Right seam length L 右 =0, while satisfying the material drop gap (14) as the preset gap (W) 预 ), L 隙 The length of the material feeding gap; In the continuous coating mode, the corresponding continuous coating initialization is as follows: the right end of the left slit roller (31.1) is aligned with the leftmost coating boundary (P). 左 The left end of the right slit roller (31.2) is aligned with the rightmost coating boundary (P). 右 ), left seam length L 左 =L 隙 Right seam length L 右 = L 隙 At the same time, the material drop gap (14) is the preset gap W. 预 L 隙 For the full length of the blanking gap (14), the left coating seam length L 左 The distance from the right end of the left gap-covering roller (31.1) to the rightmost coating boundary (P) 右 The length of the right seam is L. 右 The distance from the left end of the right slit roller (31.2) to the leftmost coating boundary (P) 左 The length of ).

9. A pipe-end white-out coating method using the pipe-end white-out control mechanism of the steel pipe curtain spreading and coating machine as described in any one of claims 1-8, characterized in that, S1 Front-end white space The steel pipe rotates and moves in a straight line along the direction of travel until the front end of the steel pipe aligns with the leftmost paint boundary (P). 左 When the blank length L is added, the right sealing roller (31.2) is started and follows the steel pipe at the same speed along the direction of travel until the left end of the right sealing roller (31.2) moves straight to align with the rightmost coating boundary (P). 右 Stop; at the same time, check and inspect the length L of the left coating seam every interval t. 左 = L 隙 ; S2 Mid-section Coating The steel pipe continues to rotate and move straight along the direction of travel, while the length L of the left coating seam is checked and inspected every time interval t. 左 = L 隙 Right seam length L 右 = L 隙 Until the rear end of the steel pipe meets the leftmost paint boundary (P) 左 Alignment; S3 backend white space The steel pipe continues to rotate and move straight along the direction of travel. When the rear end of the steel pipe meets the leftmost paint boundary (P... 左 When aligning, start the left gap-covering roller (31.1) and follow the steel pipe at the same speed along the direction of travel until the left end of the left gap-covering roller (31.1) moves straight to the rightmost coating boundary P. 右 Alignment stops, and simultaneously, the length L of the right-side coating seam is checked and verified every time interval t. 右 = L 隙 ; S4 Whitespace Initialization Simultaneously, the left and right shielding rollers (31.1 and 31.2) move at the same speed in the opposite direction of the steel pipe's travel direction until the right end of the left shielding roller (31.1) and the left end of the right shielding roller (31.2) are aligned with the leftmost coating boundary (P). 左 ), that is, the length of the right-side seam L 右 =0, left seam length L 左 =L 隙 Rotate the moving cam roller (22) so that W 隙 =W 预 .

10. The pipe end blanking coating method as described in claim 9, characterized in that, The following steps are included before step S1: S0 Verification and White Space Initialization a Double-aligned leftmost color boundary (P 左 ) Check whether the right end of the left slit roller (31.1) and the left end of the right slit roller (31.2) have moved to the leftmost coating boundary (P). 左 If this is not met, move the left gap-covering roller (31.1) or align its right end with the leftmost coating boundary (P). 左 ), left seam length L 左 =L 隙 Alternatively, if this is not satisfied, move the right slit roller (31.2) so that its left end aligns with the leftmost coating boundary (P). 左 ), right seam length L 右 =0; b. The material drop gap (14) is the preset gap W 预 Detecting material drop gap W 隙 Is it equal to W? 预 That is, to determine W 隙 -W 预 ≤E 预 Does it meet the requirements? If not, rotate the moving cam roller so that W... 隙 -W 预 ≤E 预 E 预 This is the preset error threshold.

Images