An extrusion press

Abstract

The utility model discloses an extrusion tablet press, including screw extruder and setting at its front calender. The screw cylinder front end of screw extruder is equipped with the extrusion die head of wide width, and its end forms long, flat, straight extrusion clearance, the calender has two clearance adjustable and opposite rotation's calender roller, the extrusion clearance of extrusion die head reaches the roll gap between two calender rollers, and is provided with the shunt block in the extrusion clearance, the shunt block divides the extrusion clearance into respectively corresponding two extrusion areas of upper and lower calender roller surface. The utility model utilizes shunt block and effectively homogenizes the flow velocity and pressure distribution of material in wide width direction, thereby significantly improves the thickness uniformity and edge quality of finished sheet.

Description

Technical Field

[0001] This utility model relates to the technical field of powder coating production and processing equipment, specifically to an extrusion tablet press. Background Technology

[0002] In the chemical, food, and building materials industries, it is often necessary to prepare polymer materials, ceramic blanks, and other materials into sheet-like products. Traditional production processes typically involve two steps: first, a coarse strip or block shape is extruded using a screw extruder, and then the material is calendered into sheet using a calender. During the transition from extrusion to sheeting, due to the characteristics of material flow, there is a phenomenon where the flow rate is high in the middle and slow at the sides. This leads to uneven pressure distribution of the material entering the roll gap, resulting in uneven thickness, irregular edges, and even cracking in the calendered sheet, negatively impacting subsequent processing and product quality.

[0003] Therefore, there is an urgent need in this field for an integrated extrusion and tableting equipment that can improve the uniformity of sheet thickness and edge quality. Utility Model Content

[0004] In order to overcome the above-mentioned defects of existing extrusion tableting equipment, this utility model provides an extrusion tableting machine.

[0005] The technical solution adopted by this utility model is as follows: an extrusion tablet press includes: a screw extruder, including a screw barrel, a screw disposed inside the screw barrel, and a wide extrusion die disposed at the front end of the screw barrel, the end of the extrusion die forming a long, flat, and straight extrusion gap; a calender disposed in front of the screw extruder, having two calendering rollers with adjustable gaps and opposite rotation directions; wherein, the extrusion gap of the extrusion die extends into the roller gap between the two calendering rollers; a flow divider is disposed within the extrusion gap, the flow divider dividing the extrusion gap into upper and lower extrusion areas corresponding to the roller surfaces of the two calendering rollers respectively.

[0006] Preferably, the cross-section of the diverter block in the vertical axis plane of the screw is elliptical.

[0007] Preferably, the flow divider block is thicker in the middle and thinner at both ends in the width direction of the extrusion die, so that the gap between the upper and lower extrusion areas in the width direction is larger at both sides and smaller in the middle.

[0008] Preferably, the front end of the diverter block extends from the extrusion die and into the roller gap.

[0009] Preferably, the flow divider block and the extrusion die are integrally cast structures.

[0010] Preferably, the flow divider block and the extrusion die are detachably connected.

[0011] Preferably, the upper and lower surfaces of the extrusion die and the two calendering rolls are arc-shaped.

[0012] This utility model has the following beneficial effects: 1. Integrated continuous production: By directly extending the extrusion gap of the extrusion die into the gap between the two calendering rolls, a seamless connection is achieved from molten extrusion to calendering, shortening the process flow, avoiding cooling, contamination and performance changes of materials during the transfer process, and ensuring the stability of product quality. 2. Uniform Flow Distribution: A flow distribution block is set in the extrusion gap to precisely divide the single flow channel into two independent extrusion areas corresponding to the upper and lower calendering rollers, realizing active distribution and guidance of materials. The flow distribution block adopts a "thick in the middle and thin at both ends" design in the width direction, which actively compensates for the uneven flow phenomenon of "fast flow rate in the middle and slow flow rate on both sides" that naturally exists in the wide die head. By making the extrusion gap on both sides larger than that in the middle, the material flow rate on both sides is effectively increased, so that the speed and pressure distribution of the material extruded from the entire width direction tends to be consistent, solving the problem of "thick in the middle and thin at both sides" or edge cracking of the finished sheet, and improving the thickness uniformity and edge quality of the sheet. 3. Optimized flow path: The extension of the diverter's front end into the roller gap, along with its elliptical cross-section, works together to make the material flow path smoother and more unobstructed, reducing dead zones and stress concentration, and lowering extrusion resistance. This helps protect material properties, makes the extrusion process more stable, and further ensures the reliability of molding quality. 4. High practicality: The diverter block and die head can be either integrally cast or detachably connected, which enhances the applicability of the equipment. The surface of the extrusion die head near the calender roll is designed as an arc surface, which can better fit the roll surface contour, prevent material leakage, and reduce interference with the operation of the calender roll. Attached Figure Description

[0013] Figure 1 This is a cross-sectional schematic diagram of an embodiment of the present utility model.

[0014] Figure 2 This is a left-side view of the extrusion die in an embodiment of this utility model.

[0015] 1-Barrel, 2-Screw, 3-Extrusion die, 4-Extrusion gap, 5-Calendar roll, 6-Roll gap, 7-Diverter block. Detailed Implementation

[0016] The present invention will be further described below with reference to the embodiments and accompanying drawings.

[0017] In the embodiments, such as Figure 1 , Figure 2 The image shows an extrusion tablet press, comprising: a screw extruder including a barrel 1, a screw 2 disposed inside the barrel 1, and a wide extrusion die 3 disposed at the front end of the barrel 1, the end of the extrusion die 3 forming a long, flat, and straight extrusion gap 4; and a calender disposed in front of the screw extruder, having two calendering rolls 5 with adjustable gaps and opposite rotation directions; wherein the extrusion gap 4 of the extrusion die 3 extends into the roll gap 6 between the two calendering rolls 5; a flow divider 7 is disposed within the extrusion gap 4, dividing the extrusion gap 4 into upper and lower extrusion areas corresponding to the roll surfaces of the two calendering rolls 5 respectively. By directly extending the extrusion gap 4 of the extrusion die 3 into the roll gap 6 between the two calendering rolls 5, integrated continuous production from melt extrusion to calendering is achieved, shortening the process flow, avoiding cooling and contamination during material transfer, and ensuring product quality stability. Meanwhile, a flow divider 7 is set in the extrusion gap 4 to divide the extrusion gap 4 into upper and lower extrusion areas corresponding to the roller surfaces of the two calendering rollers 5, which realizes the active distribution and guidance of materials, effectively improves the uniformity of material flow, and thus improves the thickness consistency and edge quality of the final sheet.

[0018] In the embodiments, such as Figure 1 As shown, the cross-section of the flow divider 7 in the vertical axis plane of the screw 2 is elliptical. The shape of the flow divider 7 makes the material flow path smoother and more unobstructed, reduces dead angles and stress concentration, lowers extrusion resistance, helps protect material properties and ensures the stability of the extrusion process, and further guarantees the reliability of molding quality.

[0019] In the embodiments, such as Figure 2 As shown, the flow divider 7 is thicker in the middle and thinner at both ends in the width direction of the extrusion die 3, so that the gap between the upper and lower extrusion zones in the width direction is larger at both sides and smaller in the middle, i.e., D2 > D1. This gap setting actively compensates for the uneven flow phenomenon that naturally exists in the wide extrusion die 3, where the material has a faster flow rate in the middle and a slower flow rate at both sides. By increasing the material flow rate on both sides, the extrusion speed and pressure distribution in the entire width direction tend to be uniform, effectively solving the problem of the finished sheet being thicker in the middle and thinner at both sides or cracking at the edges, and significantly improving the thickness uniformity and edge neatness of the sheet.

[0020] In the embodiments, such as Figure 1 As shown, the front end of the flow divider 7 extends from the extrusion die 3 and into the roll gap 6. The flow divider 7 further optimizes the material flow path, ensuring a smoother transition of material from the extrusion gap 4 to the roll gap 6, reducing the risk of material retention and leakage, and enhancing the continuity and stability of extrusion tableting.

[0021] In this embodiment, the diverter block 7 and the extrusion die 3 are either integrally cast or detachably connected. The integrally cast structure enhances the overall strength and sealing of the equipment, reduces the possibility of leakage at the connection points, and improves the durability and reliability of the equipment, making it suitable for high-intensity continuous production environments. The detachable connection structure facilitates the maintenance, cleaning, or replacement of the diverter block 7, enhancing the flexibility and applicability of the equipment. The configuration can be adjusted according to different production needs, reducing maintenance costs.

[0022] In the embodiments, such as Figure 1 As shown, the upper and lower surfaces of the extrusion die 3 and the two calendering rolls 5 are curved. The curved surfaces of the extrusion die 3 can better fit the roll surface contour of the calendering rolls 5, prevent material leakage at the interface, and reduce interference with the operation of the calendering rolls 5, thus ensuring the stability of the calendering process and the quality of sheet forming.

[0023] Obviously, the above embodiments of this utility model are merely examples for illustrating the present utility model, and are not intended to limit the implementation of the present utility model. Other obvious variations or modifications derived from the essential spirit of the present utility model still fall within the protection scope of the present utility model.

Claims

1. An extrusion tablet press, characterized in that, include: A screw extruder includes a screw barrel (1), a screw (2) disposed inside the screw barrel (1), and a wide extrusion die (3) disposed at the front end of the screw barrel (1), wherein the end of the extrusion die (3) forms a long, flat, and straight extrusion gap (4). The calender, located in front of the screw extruder, has two calender rolls (5) with adjustable gap and opposite rotation directions. The extrusion gap (4) of the extrusion die (3) extends into the roll gap (6) between the two calendering rolls (5); A flow divider (7) is provided in the extrusion gap (4), which divides the extrusion gap (4) into upper and lower extrusion areas corresponding to the roller surfaces of the two calendering rollers (5).

2. The extrusion tablet press according to claim 1, characterized in that, The cross-section of the diverter block (7) in the vertical axis plane of the screw (2) is elliptical.

3. The extrusion tablet press according to claim 1 or 2, characterized in that, The diverting block (7) is thick in the middle and thin at both ends in the width direction of the extrusion die (3), so that the gap between the upper and lower extrusion areas in the width direction is large on both sides and small in the middle.

4. The extrusion tablet press according to claim 1, characterized in that, The front end of the diverter block (7) extends from the extrusion die (3) and into the roller gap (6).

5. The extrusion tablet press according to claim 1, characterized in that, The diverter block (7) and the extrusion die (3) are integrally cast structures.

6. The extrusion tablet press according to claim 1, characterized in that, The flow divider block (7) and the extrusion die (3) are detachable.

7. The extrusion tablet press according to claim 1, characterized in that, The upper and lower surfaces of the extrusion die (3) and the two calendering rolls (5) are curved.

Images