Stable pulp spraying device for headbox

Abstract

The invention relates to the technical field of papermaking equipment, in particular to a stable pulp spraying device for a headbox, which comprises a pulp inlet header pipe, a conical header pipe and a return pipe, the two ends of the conical header pipe are respectively connected with the pulp inlet header pipe and the return pipe, and a pulp inlet cover is arranged on the outer surface of the conical header pipe; a plurality of slurry flowing pipes are arranged on the outer surface of the conical main pipe and located on the inner side of the slurry inlet cover, and the opening ends of the slurry flowing pipes extend out of the slurry inlet cover; the conical design of the conical main pipe enables pressure loss to be counteracted by reduction of the pipe diameter in the forward flowing process of slurry, the backflow pipe can adjust the pressure of slurry flow reaching the tail end of the pipeline, and pressure balance of the inlet end and the outlet end of the conical main pipe is kept; the conical design of the conical main pipe ensures that the pressure of the pulp flow on the full width of the headbox is consistent.

Description

Technical Field

[0001] The present invention relates to the technical field of papermaking equipment, and particularly to a stable slurry spraying device for a headbox. Background Art

[0002] With the improvement of people's living standards, the requirements for product packaging are also getting higher and higher. Now people not only require the packaging to be strong, but also various relevant information of the contents and some relevant beautiful pictures will be printed on the outer packaging. And paper with uniform basis weight often brings better printing and appearance effects.

[0003] As a key part of a modern paper machine, the structure and performance of the headbox play a decisive role in the formation of the paper sheet and the quality of the paper. In the actual production process, the external pipeline sends the slurry into the headbox, and the headbox then makes the slurry evenly fall on the forming wire through the slurry spraying mechanism, and the headbox can ensure that the flow rate of the slurry is coordinated with the moving speed of the forming wire. After the dehydration of the forming wire, the paper sheet is finally formed. It should be emphasized that during the production process of paper, if the spraying pressure of the headbox is stable, the basis weight of the paper will be more stable, and the strength index and performance of the paper will also be more uniform.

[0004] Through long-term production application, it is found that in the process of slurry discharging of the existing slurry spraying mechanism of the headbox, there is a certain deviation in the spraying pressure along the cross direction; at the same time, when the slurry discharging from the slurry pipe, the slurry is prone to flocculation in the pipe, which further affects the spraying stability and makes the paper quality uncontrollable. Therefore, we propose a stable slurry spraying device for a headbox to well solve the above drawbacks. Summary of the Invention

[0005] The purpose of the present invention is to provide a stable slurry spraying device for a headbox to solve the problems raised in the above background art.

[0006] The present invention is achieved through the following technical solutions:

[0007] A stable slurry spraying device for a headbox includes a main inlet pipe, a conical main pipe and a return pipe. The two ends of the conical main pipe are respectively connected to the main inlet pipe and the return pipe. An inlet slurry cover is arranged on the outer surface of the conical main pipe. A plurality of slurry pipes are arranged on the outer surface of the conical main pipe and inside the inlet slurry cover. The open ends of the slurry pipes extend to the outside of the inlet slurry cover;

[0008] A displacement sleeve is slidably sleeved on the outside of the inlet slurry cover. A lower lip plate is hinged to the bottom wall of the displacement sleeve, and an upper lip plate is hinged to the top wall of the displacement sleeve. A first driving component is arranged on the outside of the inlet slurry cover, and the first driving component is used to drive the displacement sleeve to slide along the length direction of the inlet slurry cover. A second driving component is arranged on the displacement sleeve, and the second driving component is used to drive the lower lip plate and the upper lip plate to rotate around their respective hinge parts;

[0009] The free end of the upper lip plate is provided with an opening fine-tuning mechanism for adjusting the opening distance between the lower lip plate and the upper lip plate.

[0010] Optionally, the pulp flow pipe is a three-section structure composed of a circular pipe section, a tapered pipe section, and a terminal pipe section connected end to end in sequence, and the circular pipe section is connected to the tapered main pipe.

[0011] Optionally, the axis directions of the slurry inlet main pipe, the tapered main pipe, and the return pipe are the same. The length of the slurry inlet main pipe is not shorter than 7 times its diameter. The diameter of one end of the tapered main pipe connected to the slurry inlet main pipe is larger than that of its other end, and the length of the return pipe is not shorter than 0.5 meters.

[0012] Optionally, the first driving assembly includes a first cylinder. The cylinder body of the first cylinder is fixedly connected to the slurry inlet cover, and the movable end of the first cylinder is fixedly connected to the displacement sleeve.

[0013] Optionally, the second driving assembly includes a lower mounting plate fixedly arranged on the bottom wall of the displacement sleeve. A vertically distributed lower sliding table cylinder is further arranged on the lower mounting plate. The movable end of the lower sliding table cylinder is hinged with a lower diagonal strut, and the end of the lower diagonal strut far from the lower sliding table cylinder is hinged with the lower lip plate.

[0014] Optionally, the second driving assembly further includes an upper mounting plate fixedly arranged on the top wall of the displacement sleeve. An upper sliding table cylinder vertically distributed is further arranged on the upper mounting plate. The movable end of the upper sliding table cylinder is hinged with an upper diagonal strut, and the end of the upper diagonal strut far from the upper sliding table cylinder is hinged with the upper lip plate.

[0015] Optionally, a hidden groove is formed on the lower surface of the free end of the upper lip plate. The opening fine-tuning mechanism includes a plug block movably arranged inside the hidden groove, and the plug block can slide along the depth direction of the hidden groove.

[0016] Optionally, the opening fine-tuning mechanism further includes a threaded rod rotatably arranged on the upper surface of the upper lip plate. One end of the threaded rod extends into the hidden groove and is threadedly connected to the plug block. A first gear is fixedly arranged at the top end of the threaded rod. A servo motor is further arranged on the upper surface of the upper lip plate. The output shaft of the servo motor is coaxially and fixedly connected with a second gear, and the second gear meshes with the first gear.

[0017] Optionally, several of the pulp flow pipes are arranged in two rows. The two rows of pulp flow pipes are arranged vertically, and the upper and lower rows of pulp flow pipes are aligned. The ends of several of the pulp flow pipes are flush with each other.

[0018] Optionally, the cross-section of the final pipe section is circular, quadrilateral or hexagonal, and the cross-sectional area of the final pipe section is not less than twice the cross-sectional area of the circular pipe section.

[0019] Compared with the prior art, the present invention provides a stable jetting device for a headbox, having the following

[0020] Beneficial effects:

[0021] 1. In the present invention, the conical design of the conical main pipe enables the pressure loss during the forward flow of the slurry to be offset by the reduction in pipe diameter, and the reflux pipe can adjust the pressure of the slurry flow reaching the end of the pipe, maintaining the pressure balance between the inlet end and the outlet end of the conical main pipe. The conical design of the conical main pipe ensures that the pressure of the slurry flow is consistent across the entire width of the headbox;

[0022] 2. In the present invention, every time the slurry passes through a cross-sectional sudden expansion in the flow pipe, a violent turbulence will be caused. Since the step size is small, the eddies generated will also be small-scale eddies. The intense mixing of the small eddies with the main slurry flow in the pipe generates a turbulence with high turbulence intensity and small turbulence degree, avoiding the flocculation of the slurry during operation;

[0023] 3. The present invention also has an opening fine-tuning mechanism, which can accurately control the opening degree of the upper and lower lip plates, thereby accurately controlling the outflow thickness of the slurry, further helping to improve the quality of paper production. Description of the Drawings

[0024] Figure 1 is a schematic structural diagram of the present invention;

[0025] Figure 2 is a schematic structural diagram of the conical main pipe of the present invention;

[0026] Figure 3 is a schematic structural diagram of the flow pipe of the present invention;

[0027] Figure 4 is Figure 1 the enlarged corresponding view at A in

[0028] In the figure: 100, inlet slurry main pipe; 200, conical main pipe; 201, inlet slurry cover; 202, displacement sleeve; 203, lower lip plate; 204, upper lip plate; 205, first driving component; 206, second driving component; 2061, lower mounting plate; 2062, lower slide table cylinder; 2063, lower inclined strut; 2064, upper mounting plate; 2065, upper slide table cylinder; 2066, upper inclined strut; 207, hidden groove; 300, reflux pipe; 400, flow pipe; 401, circular pipe section; 402, tapered pipe section; 403, final pipe section; 500, opening fine-tuning mechanism; 501, plugging block; 502, threaded rod; 503, first gear; 504, servo motor; 505, second gear. Detailed implementation mode

[0029] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0030] Please refer to Figure 1 - Figure 4 , a stable slurry spraying device for a headbox, which includes a main inlet pipe 100, a conical main pipe 200 and a return pipe 300. The two ends of the conical main pipe 200 are respectively connected to the main inlet pipe 100 and the return pipe 300. The axial directions of the main inlet pipe 100, the conical main pipe 200 and the return pipe 300 are the same. The length of the main inlet pipe 100 is not shorter than 7 times its diameter. The diameter of the end of the conical main pipe 200 connected to the main inlet pipe 100 is larger than that of its other end, and the length of the return pipe 300 is not shorter than 0.5 meters.

[0031] The conical design of the conical main pipe 200 enables the pressure loss during the forward flow of the slurry to be offset by the reduction of the pipe diameter. The return pipe 300 can adjust the pressure of the slurry flow reaching the end of the pipe, maintaining the pressure balance between the inlet end and the outlet end of the conical main pipe 200. The conical design of the conical main pipe 200 ensures that the pressure of the slurry flow is consistent across the entire width of the headbox.

[0032] Furthermore, a slurry inlet cover 201 is provided on the outer surface of the conical main pipe 200. A number of slurry flow pipes 400 are provided on the outer surface of the conical main pipe 200 and inside the slurry inlet cover 201. The open ends of the slurry flow pipes 400 extend outside the slurry inlet cover 201. The slurry flow pipe 400 is a three-section structure composed of a circular pipe section 401, a conical pipe section 402 and a terminal pipe section 403 connected end to end in sequence. The circular pipe section 401 is connected to the conical main pipe 200. A number of slurry flow pipes 400 form two rows, and the two rows of slurry flow pipes 400 are arranged vertically and are aligned. The ends of a number of slurry flow pipes 400 are flush with each other. The cross-section of the terminal pipe section 403 is circular or quadrilateral or hexagonal, and the cross-sectional area of the terminal pipe section 403 is not less than twice the cross-sectional area of the circular pipe section 401. The circular pipe at the starting section of the slurry flow pipe 400 mainly avoids excessive eddy currents generated by the change of the pipe shape when the slurry flows from the conical main pipe 200 to the slurry flow pipe 400.

[0033] It should be noted that every time the slurry passes through a cross-section sudden expansion in the slurry flow pipe 400, a violent turbulence will be caused. Since the step size is small, the generated eddy currents will also be small-scale eddy currents. The intense mixing of the small eddy currents and the main slurry flow in the pipe generates a turbulence with high turbulence intensity and small turbulence degree, avoiding the flocculation of the slurry during operation.

[0034] In some embodiments of the present application, a displacement sleeve 202 is slidably sleeved outside the pulp inlet hood 201. A lower lip plate 203 is hinged to the bottom wall of the displacement sleeve 202, and an upper lip plate 204 is hinged to the top wall of the displacement sleeve 202. A first driving assembly 205 is provided outside the pulp inlet hood 201. The first driving assembly 205 is used to drive the displacement sleeve 202 to slide along the length direction of the pulp inlet hood 201. The first driving assembly 205 includes a first cylinder. The cylinder body of the first cylinder is fixedly connected to the pulp inlet hood 201, and the movable end of the first cylinder is fixedly connected to the displacement sleeve 202. Therefore, the first cylinder can directly control the sliding of the displacement sleeve 202, thereby controlling the distance between the lower lip plate 203 and the upper lip plate 204 and the breast roll.

[0035] In addition, a second driving assembly 206 is provided on the displacement sleeve 202. The second driving assembly 206 is used to drive the lower lip plate 203 and the upper lip plate 204 to rotate around their respective hinge parts. The second driving assembly 206 includes a lower mounting plate 2061. The lower mounting plate 2061 is fixedly arranged on the bottom wall of the displacement sleeve 202. A lower slide table cylinder 2062 distributed vertically is further provided on the lower mounting plate 2061. The movable end of the lower slide table cylinder 2062 is hinged with a lower diagonal strut 2063. One end of the lower diagonal strut 2063 far from the lower slide table cylinder 2062 is hinged with the lower lip plate 203. The second driving assembly 206 further includes an upper mounting plate 2064. The upper mounting plate 2064 is fixedly arranged on the top wall of the displacement sleeve 202. An upper slide table cylinder 2065 distributed vertically is further provided on the upper mounting plate 2064. The movable end of the upper slide table cylinder 2065 is hinged with an upper diagonal strut 2066. One end of the upper diagonal strut 2066 far from the upper slide table cylinder 2065 is hinged with the upper lip plate 204. Therefore, the lower slide table cylinder 2062 is used to control the rotation of the lower lip plate 203, and the upper slide table cylinder 2065 is used to control the rotation of the upper lip plate 204, thereby controlling the opening degree of the upper and lower lip plates.

[0036] In another embodiment of the present application, an opening fine-tuning mechanism 500 is provided at the free end of the upper lip plate 204. The opening fine-tuning mechanism 500 is used to adjust the opening distance between the lower lip plate 203 and the upper lip plate 204. A hidden groove 207 is formed on the lower surface of the free end of the upper lip plate 204. The opening fine-tuning mechanism 500 includes a plug block 501 movably arranged inside the hidden groove 207. The plug block 501 can slide along the depth direction of the hidden groove 207. The cross section of the plug block 501 is rectangular, and the length direction of the plug block 501 is consistent with the length direction of the upper lip plate 204. In the initial state, the plug block 501 is completely retracted into the hidden groove 207. When the plug block 501 extends out of the hidden groove 207, the opening degree of the upper and lower lip plates will decrease, thereby realizing the opening fine-tuning function.

[0037] In addition, the opening fine-tuning mechanism 500 further includes a threaded rod 502 rotatably disposed on the upper surface of the upper lip plate 204. The axial direction of the threaded rod 502 is consistent with the depth direction of the hidden groove 207. One end of the threaded rod 502 extends into the hidden groove 207 and is threadedly connected to the plugging block 501. A first gear 503 is fixedly provided at the top end of the threaded rod 502. A servo motor 504 is further provided on the upper surface of the upper lip plate 204. The output shaft of the servo motor 504 is coaxially and fixedly connected with a second gear 505, and the second gear 505 meshes with the first gear 503. Therefore, the servo motor 504 can indirectly drive the plugging block 501 to slide through the first gear 503 and the second gear 505.

[0038] In summary, in the actual application process of this embodiment, the slurry enters the conical main pipe 200 from the slurry inlet main pipe 100, then flows out through a plurality of flow slurry pipes 400 to the lower lip plate 203, and finally flows out through the end openings of the lower lip plate 203 and the upper lip plate 204. In actual application, it is also necessary to adjust the opening degrees of the lower lip plate 203 and the upper lip plate 204 according to production needs. At this time, the angles of the lower lip plate 203 and the upper lip plate 204 can be adjusted through the second driving assembly 206. This method is for rough adjustment; then, the position of the plugging block 501 is adjusted through the servo motor 504. This method is for fine adjustment, which is used to accurately control the opening degrees of the upper and lower lip plates, so as to strictly control the paper quality and paper thickness.

[0039] It should be noted that in this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not expressly listed, or also includes elements inherent to such process, method, article or device. Without further limitation, the element defined by the statement "including an..." does not exclude the existence of additional identical elements in the process, method, article or device including the element.

[0040] Although the embodiments of the present invention have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principle and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A stable spraying device for a headbox, comprising a main feed pipe (100), a conical main pipe (200) and a return pipe (300), wherein both ends of the conical main pipe (200) are respectively connected to the main feed pipe (100) and the return pipe (300), and characterized in that: The outer surface of the conical main pipe (200) is provided with a pulp inlet hood (201), and a plurality of pulp flow pipes (400) are provided on the outer surface of the conical main pipe (200) and located inside the pulp inlet hood (201), and the open ends of the pulp flow pipes (400) extend to the outside of the pulp inlet hood (201); The external sliding sleeve of the pulp inlet hood (201) is provided with a displacement sleeve (202), the bottom wall of the displacement sleeve (202) is hingedly provided with a lower lip plate (203), the top wall of the displacement sleeve (202) is hingedly provided with an upper lip plate (204), the outside of the pulp inlet hood (201) is provided with a first driving component (205), the first driving component (205) is used to drive the displacement sleeve (202) to slide along the length direction of the pulp inlet hood (201), and the displacement sleeve (202) is provided with a second driving component (206), the second driving component (206) is used to drive the lower lip plate (203) and the upper lip plate (204) to rotate around their respective hinged parts; An opening fine-adjustment mechanism (500) is provided at the free end of the upper lip plate (204), and the opening fine-adjustment mechanism (500) is used to adjust the opening distance between the lower lip plate (203) and the upper lip plate (204).

2. A stable spraying device for a headbox according to claim 1, characterized in that: The slurry flow pipe (400) is a three-section structure consisting of a circular pipe section (401), a conical pipe section (402) and a terminal pipe section (403) connected end to end in sequence, and the circular pipe section (401) is connected to the conical main pipe (200).

3. A stable spraying device for a headbox according to claim 1, characterized in that: The axial directions of the slurry inlet main pipe (100), the conical main pipe (200) and the return pipe (300) are consistent, the length of the slurry inlet main pipe (100) is not less than 7 times its diameter, the diameter of one end of the conical main pipe (200) connected to the slurry inlet main pipe (100) is larger than the diameter of the other end, and the length of the return pipe (300) is not less than 0.5 meters.

4. A stable spraying device for a headbox according to claim 1, characterized in that: The first driving assembly (205) comprises a first cylinder, a cylinder body of the first cylinder is fixedly connected to the pulp inlet cover (201), and a movable end of the first cylinder is fixedly connected to the displacement sleeve (202).

5. The stable spraying device for a headbox according to claim 1, characterized in that: The second driving assembly (206) comprises a lower mounting plate (2061), wherein the lower mounting plate (2061) is fixedly arranged on the bottom wall of the displacement sleeve (202), and a lower sliding platform cylinder (2062) distributed vertically is also arranged on the lower mounting plate (2061), and a lower oblique support rod (2063) is hingedly arranged at the movable end of the lower sliding platform cylinder (2062), and one end of the lower oblique support rod (2063) away from the lower sliding platform cylinder (2062) is hingedly arranged to the lower lip plate (203).

6. A stable spraying device for a headbox according to claim 5, characterized in that: The second driving assembly (206) further comprises an upper mounting plate (2064), wherein the upper mounting plate (2064) is fixedly arranged on the top wall of the displacement sleeve (202), and an upper sliding cylinder (2065) distributed vertically is also arranged on the upper mounting plate (2064), and an upper oblique support rod (2066) is hingedly arranged at the movable end of the upper sliding cylinder (2065), and one end of the upper oblique support rod (2066) away from the upper sliding cylinder (2065) is hingedly arranged to the upper lip plate (204).

7. A stable spraying device for a headbox according to claim 6, characterized in that: A hidden groove (207) is provided on the lower surface of the free end of the upper lip plate (204), and the opening fine-tuning mechanism (500) comprises a blocking block (501) movably arranged inside the hidden groove (207), and the blocking block (501) can slide along the depth direction of the hidden groove (207).

8. A stable spraying device for a headbox according to claim 7, characterized in that: The opening fine-tuning mechanism (500) further comprises a threaded rod (502) rotatably arranged on the upper surface of the upper lip plate (204), one end of the threaded rod (502) extending into the hidden groove (207) and being threadedly connected to the blocking block (501), and a first gear (503) being fixedly arranged at the top end of the threaded rod (502); a servo motor (504) is also arranged on the upper surface of the upper lip plate (204), and an output shaft of the servo motor (504) is coaxially fixedly connected to a second gear (505), and the second gear (505) is meshed with the first gear (503).

9. A stable spraying device for a headbox according to claim 1, characterized in that: A plurality of the slurry flow pipes (400) form two rows, the two rows of slurry flow pipes (400) are arranged vertically, and the upper and lower rows of slurry flow pipes (400) are aligned and distributed, and the ends of the plurality of the slurry flow pipes (400) are flush with each other.

10. A stable spraying device for a headbox according to claim 2, characterized in that: The cross section of the end tube section (403) is circular, quadrilateral or hexagonal, and the cross-sectional area of ​​the end tube section (403) is not less than twice the cross-sectional area of ​​the circular tube section (401).

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