Combined screw for extrusion processing of high-content calcium sulfate whisker master batch

Abstract

The utility model discloses a combined screw rod for extrusion processing of high-content calcium sulfate whisker master batch, which comprises two screw rods meshed with each other, each screw rod comprises a core shaft and a thread element sleeved on the core shaft, and each thread element comprises a conveying block and a kneading block; a conveying section, a melting section, a first exhaust section, a first side feeding section, a first calcium sulfate whisker mixing section, a second exhaust section, a second side feeding section, a second calcium sulfate whisker mixing section, a vacuum exhaust section and a homogenizing section which are connected in sequence are formed on the mandrel by the threaded element; calcium sulfate whiskers are fed through the first side feeding opening and the second side feeding opening, and the first side feeding opening and the second side feeding opening are located in the first side feeding section and the second side feeding section respectively. The combined screw is simple in structure, convenient to use, capable of being used for producing high-content calcium sulfate whisker master batches, good in material mixing effect and capable of solving the problems that in the prior art, stable extrusion of a high-content calcium sulfate whisker system cannot be guaranteed, and the length-diameter ratio is seriously damaged.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of plastic extrusion processing equipment, specifically relates to a combined screw for high content calcium sulfate whisker master batch extrusion processing. BACKGROUND

[0002] Calcium sulfate whisker is a kind of nanometer short fiber grown by high-purity single crystal, and its aspect ratio is large (30-150), generally, polypropylene, polyethylene and other base resins are used to prepare master batch, and calcium sulfate whisker can also be mixed with other resins for injection molding and extrusion molding, and calcium sulfate whisker has significant reinforcing and toughening effects.

[0003] However, calcium sulfate whisker has small bulk density (0.15-0.2 g / cm 3 ) and large specific surface area, and can form a loose and stable "cage type" structure to adsorb a large amount of gas, water and organic small molecules. Therefore, in the processing of calcium sulfate whisker master batch, on the one hand, the "cage type" structure needs to be destroyed by increasing shear strength to complete degassing and moisture and organic small molecule devolatilization, and finally realize the infiltration and blending of base resin to calcium sulfate whisker, and calcium sulfate whisker master batch is prepared by extrusion and granulation; on the other hand, in order to fully exert the reinforcing and toughening effects of calcium sulfate whisker, the aspect ratio of calcium sulfate whisker must be kept as much as possible, so that the destruction of whisker caused by strong shear is avoided as much as possible in the processing of whisker master batch. At present, the preparation process of traditional mineral master batch such as calcium carbonate and talc mainly solves the dispersion and mixing of powder, so it is generally realized by continuous strong shear element, and thus cannot be used for the preparation of calcium sulfate whisker master batch.

[0004] Therefore, a combined screw for high content calcium sulfate whisker master batch extrusion processing needs to be designed to overcome the above technical problems. UTILITY MODEL CONTENTS

[0005] The utility model aims at: in view of the problem that the strong shear element (screw) for the preparation of traditional mineral master batch such as calcium carbonate and talc cannot be applied to the preparation of calcium sulfate whisker master batch, a combined screw for high content calcium sulfate whisker master batch extrusion processing is designed, and the combined screw can solve the problem that the current strong shear element (screw) cannot be applied to the preparation of calcium sulfate whisker master batch.

[0006] To achieve the above object, the utility model is realized by the following technical scheme:

[0007] The utility model designs a combined screw for high content calcium sulfate whisker master batch extrusion processing, the combined screw includes two intermeshing screws, the screw includes a mandrel and a threaded element sleeved on the mandrel, and the threaded element includes a conveying block and a kneading block.

[0008] The screw element forms sequentially connected conveying section, melting section, first exhaust section, first side feeding section, first calcium sulfate whisker mixing section, second exhaust section, second side feeding section, second calcium sulfate whisker mixing section, vacuum exhaust section and homogenizing section on the mandrel; calcium sulfate whisker is fed through the first side feeding port and the second side feeding port, and the first side feeding port and the second side feeding port are respectively arranged in the first side feeding section and the second side feeding section.

[0009] Specifically, the combined screw rod for high-content calcium sulfate whisker master batch extrusion processing can solve the problems that the prior art cannot guarantee stable extrusion of a high calcium sulfate whisker content system and serious length-diameter ratio damage.

[0010] Further, the combined screw rod for high-content calcium sulfate whisker master batch extrusion processing comprises the conveying section, the melting section, the first exhaust section, the first side feeding section, the first calcium sulfate whisker mixing section, the second exhaust section, the second side feeding section, the second calcium sulfate whisker mixing section, the vacuum exhaust section and the homogenizing section.

[0011] Further, the combined screw rod for high-content calcium sulfate whisker master batch extrusion processing comprises the conveying section, the melting section, the first exhaust section, the first side feeding section, the first calcium sulfate whisker mixing section, the second exhaust section, the second side feeding section, the second calcium sulfate whisker mixing section, the vacuum exhaust section and the homogenizing section.

[0012] Further, the combined screw rod for high-content calcium sulfate whisker master batch extrusion processing comprises the conveying section, the melting section, the first exhaust section, the first side feeding section, the first calcium sulfate whisker mixing section, the second exhaust section, the second side feeding section, the second calcium sulfate whisker mixing section, the vacuum exhaust section and the homogenizing section.

[0013] Further, the combined screw rod for high-content calcium sulfate whisker master batch extrusion processing comprises the conveying section, the melting section, the first exhaust section, the first side feeding section, the first calcium sulfate whisker mixing section, the second exhaust section, the second side feeding section, the second calcium sulfate whisker mixing section, the vacuum exhaust section and the homogenizing section.

[0014] Further, the combined screw rod for high-content calcium sulfate whisker master batch extrusion processing comprises the conveying section, the melting section, the first exhaust section, the first side feeding section, the first calcium sulfate whisker mixing section, the second exhaust section, the second side feeding section, the second calcium sulfate whisker mixing section, the vacuum exhaust section and the homogenizing section.

[0015] Further, the combined screw rod for high-content calcium sulfate whisker master batch extrusion processing comprises the conveying section, the melting section, the first exhaust section, the first side feeding section, the first calcium sulfate whisker mixing section, the second exhaust section, the second side feeding section, the second calcium sulfate whisker mixing section, the vacuum exhaust section and the homogenizing section.

[0016] Further, a combined screw for high content calcium sulfate whisker master batch extrusion processing: the first calcium sulfate whisker mixing section includes several kneading blocks and several conveying blocks, and at least one conveying block is arranged between adjacent two kneading blocks of the first calcium sulfate whisker mixing section, and the first calcium sulfate whisker mixing section includes at least one kneading block with a stagger angle of 45° and one SME type screw element.

[0017] The second calcium sulfate whisker mixing section includes several kneading blocks and several conveying blocks, and at least one conveying block is arranged between adjacent two kneading blocks of the second calcium sulfate whisker mixing section, and the second calcium sulfate whisker mixing section includes at least one kneading block with a stagger angle of 45° and one SME type kneading block.

[0018] Further, a combined screw for high content calcium sulfate whisker master batch extrusion processing: the second calcium sulfate whisker mixing section includes at least five mixing sections composed of kneading blocks and conveying blocks.

[0019] Further, a combined screw for high content calcium sulfate whisker master batch extrusion processing: the vacuum exhaust section includes several conveying blocks, and the lead of screw elements in the vacuum exhaust section is distributed from large to small from the vacuum exhaust section to the homogenizing section.

[0020] Further, a combined screw for high content calcium sulfate whisker master batch extrusion processing: the homogenizing section includes several conveying blocks, and the lead of screw elements in the homogenizing section is distributed from large to small from the vacuum exhaust section to the other end of the homogenizing section.

[0021] Further, a combined screw for high content calcium sulfate whisker master batch extrusion processing: the phase angle between the two intermeshing screws is 90°; the conveying blocks include forward conveying blocks and reverse conveying blocks, and the kneading blocks include K type kneading blocks and M type kneading blocks.

[0022] The beneficial effects of the utility model are as follows:

[0023] The combined screw for high content calcium sulfate whisker master batch extrusion processing has the advantages of simple structure, scientific and reasonable design, convenient use, good material mixing effect, and the like, can be used for producing high content calcium sulfate whisker master batch, and the like, and can strengthen the natural exhaust effect, eliminate the adverse effect of air carried by the calcium sulfate whisker on the extrusion stability, make the calcium sulfate whisker uniformly dispersed in the base resin, meet the stable extrusion of high content calcium sulfate whisker master batch, and the vacuum port does not emit material. BRIEF DESCRIPTION OF DRAWINGS

[0024] In order to more clearly illustrate the technical scheme of the embodiments of the present application, the drawings needed to be used in the following embodiment description will be briefly introduced, obviously, the drawings in the following description are only some embodiments of the present application, and for those skilled in the art, other drawings can be obtained according to these drawings without creative labor.

[0025] Figure 1 The structural schematic diagram of the combined screw rod for high-content calcium sulfate whisker master batch extrusion processing designed for the embodiment 1 of the present application.

[0026] The marks in the figure are as follows:

[0027] 1-conveying section, 2-melting section, 3-first exhaust section, 4-first side feeding section, 5-first calcium sulfate whisker mixing section, 6-second exhaust section, 7-second side feeding section, 8-second calcium sulfate whisker mixing section, 9-vacuum exhaust section, 10-homogenizing section, 11-screw rod, 12-core shaft. DETAILED DESCRIPTION

[0028] The technical scheme in the embodiments of the present application will be described clearly and completely in combination with the drawings in the embodiments of the present application, obviously, the described embodiments are only some embodiments of the present application, rather than all the embodiments. The description of the at least one exemplary embodiment is actually only illustrative, but not as any limitation on the present application and its application or use. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0029] In the description of the present application, it is understood that the terms "upper", "lower", "left", "right", "top", "bottom" and the like indicate the orientation or positional relationship, which is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the indicated device or element must have a particular orientation, be constructed and operated in a particular orientation, therefore it cannot be understood as a limitation on the present application. In addition, the terms "first", "second" are only for the purpose of description, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features limited by "first", "second" can be explicitly or implicitly included one or more features. Moreover, the terms "first", "second" and the like are used to distinguish similar objects, and do not have to be used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged under appropriate circumstances, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein

[0030] Embodiment 1

[0031] As Figure 1 shown in the figure, the embodiment 1 designs a combined screw for extrusion processing of high content calcium sulfate whisker master batch, the combined screw includes two structurally identical and intermeshing screws 11, and the two intermeshing screws 11 have a phase angle of 90°; the screw 11 includes a core shaft 12 and a threaded element sleeved on the core shaft 12, the threaded element includes conveying blocks and kneading blocks, the conveying blocks include forward conveying blocks and reverse conveying blocks, and the kneading blocks include K-type kneading blocks and M-type kneading blocks;

[0032] The threaded element forms conveying section 1, melting section 2, first exhaust section 3, first side feeding section 4, first calcium sulfate whisker mixing section 5, second exhaust section 6, second side feeding section 7, second calcium sulfate whisker mixing section 8, vacuum exhaust section 9 and homogenizing section 10 in sequence on the core shaft 12; calcium sulfate whiskers are fed through first and second side feeding ports located in the first and second side feeding sections 4 and 7 respectively;

[0033] The conveying section 1 includes a plurality of conveying blocks, and at least one SK-type conveying block is included in the conveying blocks constituting the conveying section 1; the lead of the threaded element of the conveying section 1 is distributed from small to large and then from large to small from the conveying section 1 to the melting section 2;

[0034] The melting section 2 includes a plurality of kneading blocks, and at least one kneading block with a misalignment angle of 90° is included in the kneading blocks constituting the melting section 2;

[0035] The first exhaust section 3 includes a plurality of conveying blocks and kneading blocks, and at least one kneading block with a misalignment angle of 60° is included in the kneading blocks constituting the first exhaust section 3; the lead of the threaded element of the first exhaust section 3 is distributed from large to small from the first exhaust section 3 to the first side feeding section 4;

[0036] The first side feeding section 4 includes a plurality of conveying blocks, and at least one SK-type conveying block is included in the conveying blocks constituting the first side feeding section 4;

[0037] The first calcium sulfate whisker mixing section 5 includes a plurality of kneading blocks and a plurality of conveying blocks, and at least one conveying block is included between adjacent two kneading blocks constituting the first calcium sulfate whisker mixing section 5; the first calcium sulfate whisker mixing section 5 includes at least one kneading block with a misalignment angle of 45°, and the first calcium sulfate whisker mixing section 5 also includes at least one SME-type threaded element;

[0038] The second exhaust section 6 comprises several conveying blocks and several kneading blocks, and the kneading blocks constituting the second exhaust section 6 at least comprise a kneading block with a stagger angle of 60°, and the lead of the thread element of the second exhaust section 6 is arranged from large to small from the second exhaust section 6 to the second side feeding section 7;

[0039] The second side feeding section 7 comprises several conveying blocks, and the conveying blocks constituting the second side feeding section 7 at least comprise an SK type conveying block;

[0040] The second calcium sulfate whisker mixing section 8 comprises several kneading blocks and several conveying blocks, and at least one conveying block is arranged between two adjacent kneading blocks constituting the second calcium sulfate whisker mixing section 8, the second calcium sulfate whisker mixing section 8 at least comprises a kneading block with a stagger angle of 45° and an SME type kneading block, and the second calcium sulfate whisker mixing section 8 at least comprises five mixing sections composed of the kneading blocks and the conveying blocks;

[0041] The vacuum exhaust section 9 comprises several conveying blocks, and the lead of the thread element of the vacuum exhaust section 9 is arranged from large to small from the vacuum exhaust section 9 to the homogenizing section 10;

[0042] The homogenizing section 10 comprises several conveying blocks, and the lead of the thread element of the homogenizing section 10 is arranged from large to small from the vacuum exhaust section 9 to the other end of the homogenizing section 10.

[0043] The combined screw rod for high-content calcium sulfate whisker master batch extrusion processing designed in the above embodiment 1 is composed of different specifications of conveying blocks and kneading blocks arranged in order on the core shaft of the screw rod, and the combined screw rod in the embodiment 1 is used for producing high-content calcium sulfate whisker master batch, which has good material mixing effect, can strengthen the natural exhaust effect, eliminate the adverse effect of air carried by the calcium sulfate whisker on the stability of extrusion, make the calcium sulfate whisker uniformly dispersed in the matrix resin, meet the stable extrusion of high-content calcium sulfate whisker master batch, and the vacuum port does not blow material; on the other hand, the combined screw rod can keep the aspect ratio of the calcium sulfate whisker as much as possible, and fully play the reinforcing and toughening effect of the calcium sulfate whisker.

[0044] Therefore, the combined screw rod for high-content calcium sulfate whisker master batch extrusion processing designed in the utility model solves the technical problems that the strong shearing element used for preparing traditional mineral master batch such as calcium carbonate and talc cannot guarantee the stable extrusion of a high-content calcium sulfate whisker system and the aspect ratio is seriously damaged.

[0045] Specifically, the combined screw rod for high-content calcium sulfate whisker master batch extrusion processing in the above embodiment 1 comprises the following specific structural arrangement:

[0046] The combined screw for extrusion processing of the high content calcium sulfate whisker master batch of example 1 has a total length of about 3764mm, the combined screw includes two intermeshing screws 11 (only one screw 11 is shown in the figure, Figure 1 , Figure 1 The screw 11 includes a core shaft 12 and a threaded element sleeved on the core shaft 12, the threaded element includes, from right to left, a conveying section 1, a melting section 2, a first exhaust section 3, a first side feeding section 4, a first calcium sulfate whisker mixing section 5, a second exhaust section 6, a second side feeding section 7, a second calcium sulfate whisker mixing section 8, a vacuum exhaust section 9, and a homogenizing section 10, each section is sequentially connected from right to left and forms an integral whole;

[0047] Among them, the conveying section 1 in example 1 includes the following threaded elements from right to left: 56 / 56A, 128 / 128, 128 / 128, 112 / 112, 72 / 72, 56 / 56, for example, 56 / 56A represents a forward conveying block with a lead of 56mm and a length of 56mm, A represents the first threaded block, 128 / 128 represents a forward conveying block with a lead of 128mm and a length of 128mm, and the remaining threaded elements can be similarly deduced; the conveying section 1 is used to smoothly feed the material at the discharge port into the screw, while compacting and heating the material, the large lead conveying block avoids the accumulation of material at the discharge port, and the screw lead gradually decreases in the second half of the conveying section 1 to compact the material and feed it into the melting section;

[0048] The melting section 2 in the above example 1 includes the following threaded elements from right to left: K30 / 7 / 72, K45 / 5 / 56, K45 / 5 / 56, K60 / 4 / 56, K90 / 5 / 36, 56 / 28L, for example, K30 / 7 / 72 represents a forward kneading block with a misalignment angle of 30°, a number of kneading discs of 7, and a length of 72mm, and the other threaded elements are similarly deduced, 56 / 28L represents a reverse conveying block with a lead of 56mm and a length of 28mm; the melting section 2 is used to achieve sufficient melting of the material and uniform mixing of the processing aid with the melt, and the melting section 2 is composed of five kneading blocks arranged in order to form an engagement zone, among them, the kneading block with a misalignment angle of 30° has weak shear force, which is used as a transition element to preliminarily compress the material from the conveying section 1, the kneading block with a misalignment angle of 45° has strong shear force and can significantly improve the dispersion and mixing of the material, the kneading block with a misalignment angle of 60° ensures the distribution and mixing of the material, and the kneading block with a misalignment angle of 90° has large shear force but long residence time of the material, therefore, at the end of the melting section 2, the kneading block with a misalignment angle of 90° and the reverse conveying block are used to prolong the residence time of the material and further strengthen the mixing effect of the material;

[0049] The first exhaust section 3 in the above embodiment 1 comprises screw elements from right to left as follows: 96 / 96, 128 / 128, K60 / 4 / 56, and the function of the first exhaust section 3 is to exhaust small molecular volatile components in the melt, the large lead screw elements in the front part of the first exhaust section 3 can increase the exhaust area, effectively removing volatile components such as moisture, and the lead gradually decreases thereafter to compact the melt, and the kneading blocks with an offset angle of 60° mainly distribute and mix, and the transverse mixing effect enhances the exhaust effect of the first side feeding section 4;

[0050] The first side feeding section 4 in the above embodiment 1 comprises screw elements from right to left as follows: 128 / 128SK, 128 / 64SK, 128 / 64SKN, 112 / 112, 96 / 96, for example, 128 / 128SK represents an SK type conveying block with a lead of 128 mm and a length of 128 mm, 128 / 64SKN represents an SKN type conveying block with a lead of 128 mm and a length of 64 mm, and the remaining screw elements can be similarly deduced; the function of the first side feeding section 4 is to add calcium sulfate whiskers through the first side feeding port (specifically, the first side feeding port is at the position of the 128 / 128SK element), and to complete the heating, compaction and conveying of the calcium sulfate whiskers; since the bulk density of calcium sulfate whiskers is small, a large amount of air will enter the screw with the calcium sulfate whiskers, and after expansion, it will seriously disturb the conveying of the melt, therefore, the front half of the first side feeding section 4 uses SK type conveying blocks with large lead, which can significantly improve the conveying capacity and prevent local accumulation of calcium sulfate whiskers, and the lead of the screw gradually decreases in the rear half to compact and feed the material into the first calcium sulfate whisker mixing section 5;

[0051] The first calcium sulfate whisker mixing section 5 in embodiment 1 comprises screw elements from right to left as follows: SME36, 56 / 56, K45 / 5 / 36, 56 / 28L, for example, SME36 represents an SME type module with a length of 36 mm, and the remaining screw elements can be similarly deduced; the function of the first calcium sulfate whisker mixing section 5 is to destroy the "cage type" structure of the calcium sulfate whiskers and complete the mixing of the calcium sulfate whiskers with the melt, while trying to retain the aspect ratio of the calcium sulfate whiskers; the SME type module has excellent transverse distribution and mixing capacity, which uniformly mixes the melt and the calcium sulfate whiskers, the kneading blocks with an offset angle of 45° mainly disperse and mix, which disperses the "cage type" structure, and at the same time, together with the reverse conveying block, prolongs the residence time of the material, and improves the mixing effect;

[0052] The second exhaust section 6 in the above embodiment 1 comprises the following screw elements from right to left: 112 / 112, 128 / 128, K60 / 4 / 56; the main function of the second exhaust section 6 is to exhaust the air and volatiles brought in by the calcium sulfate whiskers added through the first side feeding section 4; the large lead screw elements in the front part of the second exhaust section 6 can increase the exhaust area and improve the exhaust efficiency; the lead gradually decreases thereafter to compact the melt; the 60° kneading blocks mainly distribute and mix, and the transverse mixing effect strengthens the exhaust effect of the second side feeding section 7;

[0053] The second side feeding section 7 in the above embodiment 1 comprises the following screw elements from right to left: 128 / 128SK, 128 / 64SK, 128 / 64SKN, 112 / 112, 96 / 48; the function of the second side feeding section 7 is to add calcium sulfate whiskers through the second side feeding port (specifically, the second side feeding port is at the position of the 128 / 128SK element) to complete the heating, compaction and conveying of the calcium sulfate whiskers; the bulk density of the calcium sulfate whiskers is small, and a large amount of air will enter the screw along with the calcium sulfate whiskers; after expansion by heating, the air will seriously disturb the conveying of the melt; therefore, the front half of the second side feeding section 7 adopts large lead SK type conveying blocks, which not only significantly improves the conveying capacity, but also prevents the local accumulation of calcium sulfate whiskers; the lead of the screw gradually decreases in the rear half to compact the material and send it into the second calcium sulfate mixing section 8;

[0054] The second calcium sulfate mixing section 8 in the above embodiment 1 comprises the following screw elements from right to left: SME36, 56 / 56, K45 / 5 / 36, 56 / 56, K45 / 5 / 36, K45 / 5 / 36, 72 / 72, 56 / 56, K45 / 5 / 36, K45 / 5 / 36, K45 / 5 / 36L, 72 / 72, 56 / 56, K45 / 5 / 36, K45 / 5 / 36, 56 / 28L, wherein K45 / 5 / 36L represents a reverse kneading block with a stagger angle of 45°, a number of kneading discs of 5 and a length of 36 mm; the function of the second calcium sulfate mixing section 8 is to uniformly disperse the calcium sulfate whiskers in the melt while preserving the aspect ratio of the calcium sulfate whiskers as much as possible; the section includes five meshing zones, each meshing zone is separated by at least one conveying block, and the end of the section is a reverse conveying block to prolong the residence time of the material; the first and second meshing zones are respectively composed of an SME type module and a 45° kneading block, which mainly disperses the "cage type" structure of the calcium sulfate whiskers and completes the preliminary dispersion; the third meshing zone is composed of two 45° kneading blocks, the fourth meshing zone is composed of three 45° kneading blocks, the last one is a reverse kneading block, and the fifth meshing zone is composed of two 45° kneading blocks; the 45° kneading blocks mainly disperse and mix to complete the sufficient mixing of the calcium sulfate whiskers and the melt;

[0055] The vacuum exhaust section 9 in the above embodiment 1 comprises the following threaded elements from right to left: 112 / 112, 112 / 112, 96 / 96, and the function of the vacuum exhaust section 9 is to exhaust the volatile components of the melt, mainly including moisture, small molecular compounds and residual air, the large lead threaded elements are used to increase the degassing area and improve the extraction effect of the vacuum port, and the lead is gradually reduced after the threaded elements, so that the material is gradually compacted and sent into the homogenizing section 10;

[0056] The homogenizing section 10 in the above embodiment 1 comprises the following threaded elements from right to left: 72 / 72, 72 / 72, 56 / 56, 56 / 56, and the function of the homogenizing section 10 is to gradually compress the melt and establish the melt pressure to ensure the stable discharge of the die.

[0057] The above is only used for explaining the utility model, and is not used for limiting the utility model. The obvious changes or changes extended from the technical scheme of the utility model are still within the protection scope of the utility model.

Claims

1. A combination screw for extrusion processing of high content calcium sulfate whisker masterbatch, characterized by, The combined screw rod comprises two intermeshing screw rods (11), the screw rod (11) comprises a mandrel (12) and a threaded element sleeved on the mandrel (12), the threaded element comprises conveying blocks and kneading blocks; Wherein, the threaded element forms conveying section (1), melting section (2), first exhaust section (3), first side feeding section (4), first calcium sulfate whisker mixing section (5), second exhaust section (6), second side feeding section (7), second calcium sulfate whisker mixing section (8), vacuum exhaust section (9) and homogenizing section (10) in sequence on the mandrel (12); The calcium sulfate whisker is fed through the first side feeding port and the second side feeding port, and the first side feeding port and the second side feeding port are respectively located in the first side feeding section (4) and the second side feeding section (7).

2. A combination screw for extrusion processing of high content calcium sulfate whisker master granule according to claim 1, characterized in that, The conveying section (1) comprises a plurality of conveying blocks, and the conveying blocks constituting the conveying section (1) at least include one SK type conveying block. The lead of the threaded element of the conveying section (1) is distributed from small to large and then from large to small from the conveying section (1) to the melting section (2).

3. A combination screw for extrusion processing of high content calcium sulfate whisker master granule according to claim 1, characterized in that, The melting section (2) comprises a plurality of kneading blocks, and the kneading blocks constituting the melting section (2) at least include one kneading block with a stagger angle of 90°.

4. A combination screw for extrusion processing of high content calcium sulfate whisker master granule according to claim 1, characterized in that, The first exhaust section (3) comprises a plurality of conveying blocks and kneading blocks, and the kneading blocks constituting the first exhaust section (3) at least include one kneading block with a stagger angle of 60°, and the lead of the threaded element of the first exhaust section (3) is distributed from large to small from the first exhaust section (3) to the first side feeding section (4); The second exhaust section (6) comprises a plurality of conveying blocks and kneading blocks, and the kneading blocks constituting the second exhaust section (6) at least include one kneading block with a stagger angle of 60°, and the lead of the threaded element of the second exhaust section (6) is distributed from large to small from the second exhaust section (6) to the second side feeding section (7).

5. A combination screw for extrusion processing of high content calcium sulfate whisker master granule according to claim 1, characterized in that, The first side feeding section (4) comprises a plurality of conveying blocks, and the conveying blocks constituting the first side feeding section (4) at least include one SK type conveying block. The second side feeding section (7) comprises a plurality of conveying blocks, and the conveying blocks constituting the second side feeding section (7) at least include one SK type conveying block.

6. A combination screw for extrusion processing of high content calcium sulfate whisker master granule according to claim 1, characterized in that, The first calcium sulfate whisker mixing section (5) comprises a plurality of kneading blocks and conveying blocks, and at least one conveying block is arranged between adjacent two kneading blocks constituting the first calcium sulfate whisker mixing section (5), and the first calcium sulfate whisker mixing section (5) at least includes one kneading block with a stagger angle of 45° and one SME type threaded element; The second calcium sulfate whisker mixing section (8) comprises a plurality of kneading blocks and conveying blocks, and at least one conveying block is arranged between adjacent two kneading blocks constituting the second calcium sulfate whisker mixing section (8), and the second calcium sulfate whisker mixing section (8) at least includes one kneading block with a stagger angle of 45° and one SME type kneading block.

7. A combination screw for extruding high content calcium sulfate whisker master granule according to claim 1 or 6, characterized in that, The second calcium sulfate whisker mixing section (8) at least includes five mixing zones composed of kneading blocks and conveying blocks.

8. A combination screw for extrusion processing of high content calcium sulfate whisker master granule according to claim 1, characterized in that, The vacuum exhaust section (9) comprises several conveying blocks, and the lead of the threaded elements of the vacuum exhaust section (9) is distributed from large to small from the vacuum exhaust section (9) to the homogenizing section (10).

9. A combination screw for extrusion processing of high content calcium sulfate whisker master granule according to claim 1, characterized in that, The homogenizing section (10) comprises several conveying blocks, and the lead of the threaded elements of the homogenizing section (10) is distributed from large to small from the vacuum exhaust section (9) to the other end of the homogenizing section (10).

10. A combination screw for extrusion processing of high content calcium sulfate whisker master granule according to claim 1, characterized in that, The phase angle between the two intermeshing screws (11) is 90°; the conveying blocks comprise forward conveying blocks and reverse conveying blocks, and the kneading blocks comprise K-type kneading blocks and M-type kneading blocks.

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