Papermaking filter press dewatering boot processing equipment

Abstract

The present application provides a papermaking filter press dewatering boot sleeve processing equipment, which belongs to the field of papermaking boot sleeve processing. The papermaking filter press dewatering boot sleeve processing equipment includes a fixed roller, a movable roller, a spraying unit and a forming roller. The boot sleeve blank is tensioned by cooperating with the fixed roller and the movable roller, and then the polyurethane coating is sprayed or poured onto the outer surface of the boot sleeve blank by the spraying unit. Before the polyurethane coating is cured, the boot sleeve blank is squeezed by the forming roller. The diameter of the forming roller is the same as that of the predetermined pair of rollers, so that the boot sleeve blank forms grooves when it is concave into the use state; when the boot sleeve thus made is squeezed with the pair of rollers, the groove of the boot sleeve is concave into the original state, avoiding the deformation stress caused by the concave, reducing the force of the boot sleeve, and thus slowing down the cracking of the groove to a certain extent, extending the service life of the boot sleeve.

Description

Technical Field

[0001] The present application belongs to the technical field of papermaking boot processing, and more specifically, relates to a papermaking filter press dewatering boot processing equipment. Background Art

[0002] The most common filter pressing and dewatering process in the papermaking process is roller filter pressing, which uses two rollers to press and dehydrate the wet paper sheets. The two important technical indicators of roller filter pressing are the nip pressure and the nip width. In conventional round roller squeezing mechanisms, even if the diameter of the filter press roller is designed to be larger (up to nearly two meters), it is difficult to significantly increase the nip width, and the dewatering effect is not much improved. Later, the boot filter pressing technology appeared. This technology uses a boot roller and a circular counter-roller to squeeze each other. A flexible boot sleeve is provided on the outer surface of the boot roller. The boot roller presses the boot sleeve against the circular counter-roller through the concave boot plate. The boot sleeve deforms to match the counter-roller, thereby greatly increasing the nip width with the counter-roller and improving the dewatering effect. As a result, it has been widely used.

[0003] Since the width of the pressure zone between the boot sleeve and the counter-roller is relatively large in the boot filter press, in order to allow the escaped water to be discharged smoothly, it is necessary to provide grooves on the outer surface of the boot sleeve so that the escaped water can be discharged smoothly from the pressure zone along the grooves. The inventors of this application are aware of two methods for processing the grooves of the boot sleeve: one is to use a support roller to open the main body of the boot sleeve after the main body of the boot sleeve is processed, and grooves are processed on the outer surface of the boot sleeve by cutting; the other is to put the tubular mesh into a cylindrical mold, and then cast it into a cylindrical boot sleeve, and the inner wall of the mold is provided with corresponding patterns to form grooves. However, the boot sleeves currently produced are prone to cracks along the edges and corners of the grooves after long-term use. These cracks will greatly affect the quality of the paper. When the cracks of the boot sleeve reach a certain level, it will be completely scrapped and can only be replaced. Summary of the Invention

[0004] In view of this, an embodiment of the present application provides a papermaking filter press dewatering boot processing device to solve the technical problem in the prior art that the outer surface of the boot is prone to cracks along the edges and corners of the grooves.

[0005] To achieve the above objectives, the technical solution adopted in this application is:

[0006] On the one hand, a papermaking filter press dewatering boot processing device is provided, comprising:

[0007] Fixed roller;

[0008] The movable roller is movably arranged close to or away from the fixed roller, and is suitable for cooperating with the fixed roller to tension the boot cover blank:

[0009] A spraying unit, adapted to spray or pour a polyurethane coating onto the outer surface of the tensioned boot cover blank;

[0010] The forming roller has the same diameter as the predetermined pair of rollers and an outer surface provided with concave and convex patterns for forming grooves;

[0011] The forming roller is adapted to move to an operating position to squeeze the tensioned boot cover blank so that the boot cover blank is bent into an arc shape that matches the outer surface of the forming roller. During the process, the movable roller moves closer to the fixed roller.

[0012] After the spraying unit sprays or pours the polyurethane coating onto the outer surface of the boot cover blank, the forming roller squeezes the boot cover blank and rotates to form grooves on the polyurethane coating on the outer surface of the boot cover blank;

[0013] The forming roller is adapted to be retracted to an initial position to be separated from the boot cover blank, and the movable roller moves away from the fixed roller to keep the boot cover blank taut.

[0014] In some embodiments, the papermaking filter press dewatering boot processing equipment also includes an arc-shaped pressure back plate, which is located inside the boot blank. When the forming roller moves to the operating position, the pressure back plate cooperates with the forming roller to clamp the boot blank.

[0015] In some embodiments, a plurality of heat medium cavities are provided inside the pressure back plate, each of the heat medium cavities is arranged along the axial direction of the forming roller, and the plurality of heat medium cavities are distributed along the circumference of the forming roller, and in the rotation direction of the forming roller, the medium temperature in each of the heat medium cavities gradually decreases.

[0016] In certain embodiments, the papermaking filter press dewatering boot processing equipment further includes a support roller, which is located inside the boot blank and supports the side of the boot blank facing away from the fixed roller.

[0017] In some embodiments, within the movable range of the movable roller, the support roller always supports the boot cover blank;

[0018] The spraying unit is located on a side of the tensioned boot cover blank facing away from the forming roller, and is opposite to a portion of the boot cover blank located between the supporting roller and the fixed roller.

[0019] In some embodiments, a mold release nozzle is provided on the side of the forming roller facing away from the tensioned boot cover blank.

[0020] In certain embodiments, the boot cover blank has a thickness of more than 2 cm and has a mesh layer inside.

[0021] The beneficial effect of the papermaking filter press dewatering boot sleeve processing equipment provided in the embodiment of the present application is that: compared with the prior art, the papermaking filter press dewatering boot sleeve processing equipment in the embodiment of the present application utilizes a fixed roller and a movable roller to tension the boot sleeve blank, and then sprays or pours a polyurethane coating onto the outer surface of the boot sleeve blank through a spraying unit. Before the polyurethane coating is cured, the boot sleeve blank is squeezed by a forming roller, and the diameter of the forming roller is the same as that of a predetermined pair of rollers, so that the boot sleeve blank forms a groove when it is concave into a use state; when the boot sleeve thus made is squeezed with the pair of rollers, the groove of the boot sleeve is concave into its original state, avoiding the deformation stress caused by the concave, reducing the force on the boot sleeve, and thus slowing down the cracking of the groove to a certain extent, thereby extending the service life of the boot sleeve. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the embodiments or descriptions of the prior art. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0023] Figure 1 This is a schematic diagram of the boot cover in use;

[0024] Figure 2 This is a front view of the papermaking filter press dewatering boot processing equipment provided in an embodiment of the present application, wherein the forming roller is in the initial position;

[0025] Figure 3 for Figure 2 Schematic diagram of the forming roller after it moves to the working position;

[0026] Figure 4 for Figure 2 Schematic diagram of the structure of the pressure backplate.

[0027] Among them, the reference numerals in the figures are:

[0028] 1-Fixed roller; 2-Moveable roller; 3-Spraying unit; 4-Forming roller; 41-Release agent nozzle; 5-Pressure back plate; 51-Heat medium chamber; 6-Support roller; 7-Shoe sleeve blank; 8-Shoe roller; 81-Shoe sleeve; 9-Pair of rollers. DETAILED DESCRIPTION

[0029] In order to make the technical problems, technical solutions and beneficial effects to be solved by this application more clearly understood, this application is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not intended to limit this application.

[0030] It should be noted that when an element is referred to as being “fixed on” or “disposed on” another element, it may be directly on the other element or indirectly on the other element. When an element is referred to as being “connected to” another element, it may be directly connected to the other element or indirectly connected to the other element.

[0031] It should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this application.

[0032] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of the technical features indicated. Thus, a feature specified as "first" or "second" may explicitly or implicitly include one or more of the features. Throughout the description of this application, "plurality" or "several" means two or more, unless otherwise specifically defined.

[0033] Traditionally, it is believed that the principle of boot filter press is to increase the width of the pressure zone by squeezing and deforming the boot sleeve to improve the dehydration effect. Therefore, the boot sleeve will inevitably be subjected to repeated squeezing and bending, and cracks will inevitably occur after long-term use. The only way to delay the occurrence of cracks is to improve the material properties of the boot sleeve.

[0034] The inventors of this application conducted an in-depth study on the causes of cracks in the boot sleeve and found that: it is generally believed that the boot sleeve works on a nearly circular boot roller, so the current boot sleeves are all processed according to the cylindrical shape. After the boot sleeves are put on the circular boot roller, although most of the boot sleeves are in their original state, the concave part due to contact between the boot sleeve and the counter roller has produced greater deformation. This deformation, together with factors such as friction and extrusion, acts on the boot sleeve, greatly accelerating the appearance of cracks; in particular, the grooves on the outer surface of the boot sleeve have the largest deformation, and the edges and corners of the grooves are relatively weak, causing cracks to appear in this area first. Therefore, the inventors proposed the solution of this application.

[0035] Please also refer to Figures 1 to 4 The papermaking filter press dewatering boot processing equipment provided in the embodiment of the present application is now described. A papermaking filter press dewatering boot processing equipment includes: a fixed roller, a movable roller, a spraying unit, and a forming roller.

[0036] The fixed roller is a cylindrical roller body, which can be passively rotated or actively rotated by a power unit. A heat medium channel can be provided inside the fixed roller to control the temperature of the fixed roller as needed.

[0037] The movable roller is configured to move toward or away from the fixed roller, and is suitable for cooperating with the fixed roller to tension the boot cover blank. During implementation, the movable roller moves toward or away from the fixed roller via a vertical slide rail structure. The movable roller is pulled upward by a tension spring or the counterweight of a bypass pulley, causing the movable roller to automatically slide upward and cooperate with the fixed roller below to tension the boot cover blank.

[0038] The movable roller can be powered by an electric motor. When the forming roller is pressed against the boot blank, the movable roller drives the boot blank and the forming roller to rotate synchronously, thereby forming grooves on the outer surface of the boot blank. A heat medium channel can be provided inside the movable roller to control the temperature of the movable roller as needed.

[0039] The spraying unit is suitable for spraying or pouring a polyurethane coating onto the outer surface of the tensioned boot cover body. The spraying unit uses a spraying or pouring structure to evenly deposit the melted polyurethane onto the outer surface of the boot cover body, forming a polyurethane coating. Before the polyurethane coating is fully cured, a forming roller is used to press the polyurethane coating into grooves.

[0040] The forming roller has the same diameter as the predetermined counterroll. After the forming roller compresses the boot blank, it bends into the arc shape of the predetermined counterroll, forming the grooves. The outer surface of the forming roller is provided with a concave and convex pattern to form the grooves. The shape of the concave and convex pattern can be customized. The depth of the concave and convex pattern is generally between 1 and 2 mm. A heat medium channel can be provided inside the forming roller to control the forming roller temperature as needed.

[0041] The forming roller is adapted to move to its operating position to compress the tensioned boot blank, bending it into an arc that conforms to the outer surface of the forming roller. During this process, the movable roller is pulled downward toward the fixed roller. In practice, the base of the forming roller can be equipped with moving wheels or slides for horizontal movement, powered by an electric motor or hydraulic cylinder. During use, the surface of the forming roller can be sprayed with a release agent to prevent sticking.

[0042] After the spraying unit sprays or pours the polyurethane coating onto the outer surface of the boot cover, the forming roller squeezes the boot cover and rotates, forming grooves in the polyurethane coating on the outer surface of the boot cover. The forming roller is adapted to retract to its initial position to separate from the boot cover, and the movable roller moves away from the fixed roller to keep the boot cover taut.

[0043] Compared with the prior art, the papermaking filter press dewatering boot processing equipment of the embodiment of the present application utilizes a fixed roller and a movable roller to tension the boot blank, and then sprays or pours a polyurethane coating onto the outer surface of the boot blank through a spraying unit. Before the polyurethane coating is cured, the boot blank is squeezed by a forming roller. The diameter of the forming roller is the same as that of a predetermined pair of rollers, so that the boot blank forms grooves when it is concave into a use state; when the boot thus made is squeezed with the pair of rollers, the grooves of the boot are concave into their original state, avoiding the deformation stress caused by the concavity, reducing the force on the boot, and thereby slowing down the cracks in the grooves to a certain extent, thereby extending the service life of the boot.

[0044] In practice, the boot cover blank is a cylindrical blank that has undergone prior processing, typically a tubular mesh formed by spraying or pouring polyurethane. For details, please refer to current boot cover processing methods. Compared to the finished boot cover, the boot cover blank lacks the grooved layer on its outer surface, making it thinner than the finished boot cover. This facilitates the formation of the grooved layer on the outer surface of the boot cover blank using the papermaking filter press dewatering boot cover processing equipment of the present application.

[0045] As a possible way of using it: first, the boot cover blank is put on the fixed roller and the movable roller and tensioned; then, the boot cover blank rotates, and the spraying unit sprays or pours a small amount of polyurethane onto the outer surface of the boot cover blank for the first time; when the polyurethane sprayed or poured for the first time is close to solidification, the forming roller is immediately moved to the working position, so that the forming roller squeezes the tensioned boot cover blank, and the boot cover blank rotates synchronously with the forming roller. At the same time, the spraying unit sprays or pours polyurethane onto the outer surface of the boot cover blank for the second time, and the forming roller squeezes the twice sprayed or poured polyurethane coating to form grooves. During the process, the ambient temperature or the temperature of the fixed roller, movable roller and forming roller can be controlled to control the solidification of the polyurethane coating. Of course, in the specific implementation, the working process of the filter press dewatering boot cover processing equipment for papermaking is not limited to this, and this is just an example.

[0046] See also Figure 2 and Figure 3 As a specific embodiment of the papermaking filter press dewatering boot processing equipment provided by this application, the papermaking filter press dewatering boot processing equipment also includes a curved pressure back plate. The pressure back plate is located inside the boot body. When the forming roller moves to the operating position, the pressure back plate and the forming roller cooperate to clamp the boot body. The pressure back plate not only provides support for the boot body when being squeezed by the forming roller, but also controls the overall thickness of the boot.

[0047] In practice, the pressure backplate is arc-shaped. When the forming roller moves to its operating position, the pressure backplate and the center of the forming roller coincide. The pressure between the forming roller and the pressure backplate should not be excessive to prevent excessive rotational resistance to the boot blank. Resistance can be reduced by shortening the length of the pressure backplate along the circumference of the forming roller. Alternatively, the pressure backplate can be designed to be discontinuous along the circumference of the forming roller to reduce resistance. Alternatively, a release agent can be sprayed on the contact surface between the pressure backplate and the boot blank for lubrication.

[0048] See also Figures 2 to 4 As a specific embodiment of the papermaking filter press dewatering boot processing equipment provided in this application, a plurality of heat medium cavities are provided inside the pressure back plate, each heat medium cavity is arranged along the axial direction of the forming roller, and the plurality of heat medium cavities are distributed along the circumference of the forming roller, and in the rotation direction of the forming roller, the medium temperature in each heat medium cavity gradually decreases.

[0049] During use, when the forming roller moves to the working position to extrude the boot cover blank, the medium temperature in each heat medium cavity gradually decreases, which can control the polyurethane coating to be gradually cooled and solidified during the process of passing through the pressure back plate.

[0050] In specific implementation, the medium can be steam or heat transfer oil.

[0051] See also Figure 2 and Figure 3 As a specific embodiment of the papermaking filter press dewatering boot sleeve processing equipment provided in this application, the papermaking filter press dewatering boot sleeve processing equipment also includes a support roller, which is located inside the boot sleeve blank and supports the side of the boot sleeve blank facing away from the fixed roller outward to expand the internal space of the boot sleeve blank to facilitate accommodating a larger pressure back plate.

[0052] In this embodiment, the fixed roller, movable roller and support roller are arranged in a triangle, and the boot cover blank is wrapped around the outside of the three to form a triangle. One or more of the fixed roller, movable roller and support roller are equipped with a drive motor to drive the boot cover blank.

[0053] See also Figure 2 and Figure 3 As a specific embodiment of the papermaking filter press dewatering boot processing equipment provided in this application, within the movable range of the movable roller, the support roller always supports the boot blank, so that when the movable roller moves, the part of the boot blank located between the support roller and the fixed roller will not move.

[0054] The spraying unit is located on the side of the tensioned boot sleeve blank facing away from the forming roller, and is opposite to the part of the boot sleeve blank located between the supporting roller and the fixed roller. When the movable roller moves, the position of this part of the boot sleeve blank will not change, and the spraying unit is opposite to this part of the boot sleeve blank. The spraying unit does not need to move and can always be opposite to the boot sleeve blank, thereby simplifying the overall structure.

[0055] See also Figure 2 and Figure 3 As a specific embodiment of the papermaking filter press dewatering boot sleeve processing equipment provided in this application, a release agent nozzle is provided on the side of the forming roller facing away from the tensioned boot sleeve blank.

[0056] In this embodiment, the release agent nozzle and its accessories are fixedly mounted on the base of the forming roller.

[0057] See also Figure 2 and Figure 3 As a specific embodiment of the papermaking filter press dewatering boot processing equipment provided in this application, the thickness of the boot blank is more than 2 cm, and there is a woven mesh layer inside to reduce the deformation of the boot blank during rotation.

[0058] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present application should be included in the scope of protection of the present application.

Claims

1. Papermaking filter press dewatering boot processing equipment, characterized in that: include: Fixed roller; The movable roller is movably arranged close to or away from the fixed roller, and is suitable for cooperating with the fixed roller to tension the boot cover blank: A spraying unit, adapted to spray or pour a polyurethane coating onto the outer surface of the tensioned boot cover blank; The forming roller has the same diameter as the predetermined pair of rollers and an outer surface provided with concave and convex patterns for forming grooves; The forming roller is adapted to move to an operating position to squeeze the tensioned boot cover blank so that the boot cover blank is bent into an arc shape that matches the outer surface of the forming roller. During the process, the movable roller moves closer to the fixed roller. After the spraying unit sprays or pours the polyurethane coating onto the outer surface of the boot cover blank, the forming roller squeezes the boot cover blank and rotates to form grooves on the polyurethane coating on the outer surface of the boot cover blank; The forming roller is adapted to retract to an initial position to separate from the boot cover blank, and the movable roller moves away from the fixed roller to keep the boot cover blank taut; The papermaking filter press dewatering boot processing equipment further includes an arc-shaped pressure back plate, which is located inside the boot blank. When the forming roller moves to the working position, the pressure back plate cooperates with the forming roller to clamp the boot blank. A plurality of heat medium cavities are provided inside the pressure back plate, each of the heat medium cavities is arranged along the axial direction of the forming roller, and the plurality of heat medium cavities are distributed along the circumference of the forming roller. In the rotation direction of the forming roller, the medium temperature in each of the heat medium cavities gradually decreases.

2. The papermaking filter press dewatering boot processing equipment according to claim 1, characterized in that: The papermaking filter press dewatering boot processing equipment further includes a support roller, which is located inside the boot blank and supports the side of the boot blank facing away from the fixed roller.

3. The papermaking filter press dewatering boot processing equipment according to claim 2, characterized in that: Within the movable range of the movable roller, the supporting roller always supports the boot cover blank; The spraying unit is located on a side of the tensioned boot cover blank facing away from the forming roller, and is opposite to a portion of the boot cover blank located between the supporting roller and the fixed roller.

4. The papermaking filter press dewatering boot processing equipment according to claim 3, characterized in that: A mold release agent nozzle is provided on the side of the forming roller facing away from the tensioned boot cover blank.

5. The papermaking filter press dewatering boot processing equipment according to claim 1, characterized in that: The thickness of the boot cover blank is more than 2 cm, and a mesh layer is provided inside.

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