Intermittent variable pressure segmental tea rolling method
Patent Information
- Application Number
- CN202611161038.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-08-03
- Publication Date
- 2026-10-30
AI Technical Summary
[0004]针对现有技术的不足，本发明提供了一种间歇变压分段的茶叶揉捻方法，通过基于驱动负载和压盖位移的局部压实识别，并实施减压反向重分布及复压验证，解决茶叶揉捻过程中局部结团压实、受力不均的问题
[0018]该间歇变压分段的茶叶揉捻方法，在各揉捻压力阶段内同步获取揉捻驱动负载和压盖位移变化量，并以驱动负载增大、压盖位移受限作为局部压实状态的判定依据，能够将茶叶正常受压压缩过程与因局部结团引起的阻力集中状态进行区分。在识别到局部压实状态后，控制压盖减压，并控制揉盘实施反向重分布转动，使局部压实的茶叶在较低压力下松散、翻动和重新分布，避免茶叶在持续施压状态下发生局部过度挤压，从而有利于改善揉捻过程中的受力均匀性，降低碎叶、断条及茶汁过度外溢的风险。
Smart Images
Figure CN122997221A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of tea processing technology, specifically to a method for intermittent, variable-pressure, segmented tea rolling. Background Technology
[0002] Current tea rolling processes typically employ rolling machines to apply pressure, kneading, and friction to withered or dead-green leaves, causing them to curl into strips and resulting in some leaf tissue breakage and leakage of tea juice. Current rolling processes usually use constant pressure rolling, or apply different pressures—light, medium, heavy, and loose—sequentially according to a preset time to accommodate the rolling process from initial curling to tight compaction of the tea leaves. Some processes also include loosening and breaking up clumps at the end of rolling or between two rolling stages to reduce tea clumping.
[0003] However, existing segmented pressing methods usually maintain continuous pressure in each pressure stage. After the tea leaves are locally compacted and clump together, it is difficult to loosen and redistribute them in time, which can easily lead to uneven force during tea rolling. Summary of the Invention
[0004] To address the shortcomings of existing technologies, this invention provides an intermittent variable pressure segmented tea rolling method. By identifying local compaction based on driving load and cap displacement, and implementing decompression reverse redistribution and re-compression verification, the method solves the problems of local agglomeration and uneven stress during tea rolling.
[0005] To achieve the above objectives, the present invention provides the following technical solution: a method for intermittent, variable-pressure, segmented tea kneading, comprising:
[0006] S1. The tea leaves to be kneaded are put into the kneading chamber of the kneading machine, and the kneading process is divided into at least two kneading pressure stages executed sequentially; for each kneading pressure stage, a target kneading pressure, a reduced kneading pressure, a load increment threshold, and a cap displacement threshold are set, and the target kneading pressure of adjacent kneading pressure stages is different, and the reduced kneading pressure is less than the target kneading pressure of the corresponding kneading pressure stage;
[0007] S2. During the current kneading pressure stage, control the pressure cap to apply pressure to the tea leaves to be kneaded with the corresponding target kneading pressure, and control the kneading disc to rotate in the forward kneading direction; after the target kneading pressure stabilizes, obtain the reference drive load of the kneading drive mechanism, and obtain the current drive load and the displacement change of the pressure cap in the pressure direction in subsequent monitoring cycles;
[0008] S3. When, within the same monitoring cycle, the increase in the current driving load relative to the reference driving load reaches the load increment threshold, and the displacement change of the pressure cap is not greater than the pressure cap displacement threshold, it is determined that the tea leaves to be kneaded are in a locally compacted state; in response to the locally compacted state, the pressure applied by the pressure cap is controlled to decrease from the target kneading pressure to the reduced kneading pressure, and the kneading disc is controlled to switch from the forward kneading direction to the reverse redistribution direction; after the reverse rotation is completed, the kneading disc is controlled to resume rotation along the forward kneading direction, and the pressure applied by the pressure cap is restored to the target kneading pressure;
[0009] S4. After the applied pressure is restored to the target kneading pressure, the displacement changes of the current driving load and the cap are reacquired, and the local compaction state is determined based on the increase of the current driving load relative to the reference driving load and the displacement change of the cap. When the local compaction state is released, kneading continues at the current kneading pressure stage. When the local compaction state is not released, S3 is repeated. After the current kneading pressure stage reaches the corresponding preset kneading time, the process switches to the next kneading pressure stage until all kneading pressure stages are completed, and the kneaded tea leaves are obtained.
[0010] Preferably, the kneading drive mechanism includes a drive motor that drives the kneading disc to rotate, and the current drive load is the output torque of the drive motor; the displacement change of the pressure cap is collected by a linear displacement sensor disposed on the lifting path of the pressure cap.
[0011] Preferably, the reference drive load is the arithmetic average of the output torque of the drive motor collected during three consecutive reference monitoring cycles in which the pressure cap maintains the target kneading pressure; the current drive load is the maximum value of the output torque of the drive motor in the corresponding monitoring cycle.
[0012] Preferably, the determination of the local compaction state includes: within at least two consecutive monitoring cycles, the increase of the current driving load relative to the reference driving load reaches the load increment threshold, and the displacement change of the cap is not greater than the cap displacement threshold.
[0013] Preferably, controlling the kneading disc to switch from the forward kneading direction to the reverse redistribution direction includes: stopping the rotation of the kneading disc along the forward kneading direction, and then controlling the kneading disc to rotate along the reverse redistribution direction, which is opposite to the forward kneading direction; during the rotation of the kneading disc along the reverse redistribution direction, the pressure cap maintains the reduced kneading pressure; when the cumulative number of reverse rotations of the kneading disc reaches a preset number of reverse rotations, stopping the reverse rotation of the kneading disc, and controlling the kneading disc to resume rotation along the forward kneading direction.
[0014] Preferably, the determination of the release of the local compaction state includes: after the pressure applied by the cap returns to the target kneading pressure, the displacement change of the current driving load and the cap is reacquired within at least two consecutive verification monitoring cycles; in each verification monitoring cycle, if the increase of the current driving load relative to the reference driving load is less than the load increment threshold, or if the displacement change of the cap is greater than the cap displacement threshold, the local compaction state is determined to be released.
[0015] Preferably, the kneading pressure stage includes a first kneading pressure stage, a second kneading pressure stage, and a third kneading pressure stage executed sequentially; the target kneading pressure of the second kneading pressure stage is greater than the target kneading pressure of the first kneading pressure stage, and is also greater than the target kneading pressure of the third kneading pressure stage.
[0016] Preferably, when the kneading pressure stage reaches the corresponding preset kneading time, it is determined whether the tea leaves to be kneaded are still in the local compaction state; when the tea leaves to be kneaded are still in the local compaction state, the kneading pressure stage is maintained and S3 is repeated; after the local compaction state is released, the process switches to the next kneading pressure stage.
[0017] This invention provides a method for intermittent, variable-pressure, segmented tea rolling. It has the following beneficial effects:
[0018] This intermittent, variable-pressure, segmented tea rolling method simultaneously acquires changes in the rolling drive load and cap displacement during each rolling pressure stage. It uses increased drive load and restricted cap displacement as criteria for determining local compaction, distinguishing between the normal compression process of tea leaves and resistance concentration caused by localized clumping. Upon identifying local compaction, the cap is depressurized, and the rolling disc rotates in the opposite direction for redistribution. This loosens, turns, and redistributes the locally compacted tea leaves under lower pressure, preventing excessive local compression under continuous pressure. This improves the uniformity of force during rolling and reduces the risk of broken leaves, broken strips, and excessive tea juice leakage.
[0019] Furthermore, this invention restores the target kneading pressure after decompression and reverse redistribution, and re-determines whether the local compaction state has been relieved based on the changes in drive load and cap displacement; it only continues the current kneading pressure stage or switches to the next kneading pressure stage after the local compaction state has been relieved, forming a closed-loop control of local compaction identification, decompression and redistribution, re-pressure verification, and segmented kneading. This control method can reduce the need for repeated trial adjustments based on a fixed pressure sequence, matching different kneading pressure stages with the actual pressure state of the tea leaves, which is beneficial to improving the consistency of tea leaf formation and the stability of the kneading process. Attached Figure Description
[0020] Figure 1 This is an overall flowchart of the tea rolling method of the present invention;
[0021] Figure 2 This is a flowchart illustrating the intermittent variable pressure closed-loop control process for the localized compaction state of tea leaves according to the present invention. Detailed Implementation
[0022] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0023] Example 1
[0024] like Figure 1-2 As shown, this embodiment of the invention provides an intermittent variable pressure segmented tea kneading method, including a kneading machine comprising a pressing cap, a kneading disc, a kneading drive mechanism, a pressing cap drive mechanism, a linear displacement sensor, and a controller; the controller is used to acquire the output torque of the kneading drive mechanism and the displacement signal of the pressing cap, and accordingly control the pressure applied by the pressing cap and the rotation direction of the kneading disc.
[0025] S1. Put the tea leaves to be kneaded into the kneading chamber of the kneading machine, and divide the kneading process into at least two kneading pressure stages executed sequentially; for each kneading pressure stage, set the target kneading pressure, the decompression kneading pressure, the load increment threshold and the cap displacement threshold. The target kneading pressure of adjacent kneading pressure stages is different, and the decompression kneading pressure is less than the target kneading pressure of the corresponding kneading pressure stage.
[0026] S2. During the current kneading pressure stage, control the pressure cap to apply pressure to the tea leaves to be kneaded at the corresponding target kneading pressure, and control the kneading disc to rotate in the forward kneading direction; after the target kneading pressure stabilizes, obtain the reference drive load of the kneading drive mechanism, and obtain the current drive load and the displacement change of the pressure cap in the pressure direction in subsequent monitoring cycles.
[0027] The kneading drive mechanism includes a drive motor that drives the kneading disc to rotate, and the current drive load is the output torque of the drive motor; the displacement change of the pressure cap is collected by a linear displacement sensor set on the lifting path of the pressure cap.
[0028] The baseline drive load is the arithmetic mean of the output torque of the drive motor collected during three consecutive baseline monitoring cycles in which the pressure cap maintains the target kneading pressure; the current drive load is the maximum value of the output torque of the drive motor in the corresponding monitoring cycle.
[0029] The displacement change of the gland is the increment of the gland's displacement along the pressure direction within the same monitoring cycle; the controller determines the maximum output torque of the drive motor within this monitoring cycle as the current drive load.
[0030] S3. When the increase in the current driving load relative to the reference driving load reaches the load increment threshold within the same monitoring cycle, and the displacement change of the cap is not greater than the cap displacement threshold, it is determined that the tea leaves to be kneaded are in a locally compacted state; in response to the locally compacted state, the pressure applied by the cap is controlled to be reduced from the target kneading pressure to the reduced kneading pressure, and the kneading disc is controlled to switch from the forward kneading direction to the reverse redistribution direction; after the reverse rotation is completed, the kneading disc is controlled to resume rotation along the forward kneading direction, and the pressure applied by the cap is restored to the target kneading pressure.
[0031] When tea leaves are under normal pressure, the pressure cap can continue to move along the direction of pressure. When the tea leaves are locally compacted or clumped together, the resistance of the kneading disc increases, the output torque of the drive motor increases, and the displacement of the pressure cap is restricted. Therefore, the local compaction state can be identified based on the combination of the drive load and the change in pressure cap displacement.
[0032] The determination of local compaction status includes: within no less than two consecutive monitoring cycles, the increase of the current driving load relative to the reference driving load reaches the load increment threshold, and the displacement change of the gland does not exceed the gland displacement threshold.
[0033] The control of the kneading disc to switch from the forward kneading direction to the reverse redistribution direction includes: after stopping the rotation of the kneading disc along the forward kneading direction, controlling the kneading disc to rotate along the reverse redistribution direction, which is opposite to the forward kneading direction; during the rotation of the kneading disc along the reverse redistribution direction, the pressure cap maintains the reduced kneading pressure; when the cumulative number of reverse rotations of the kneading disc reaches the preset number of reverse rotations, stopping the reverse rotation of the kneading disc, and controlling the kneading disc to resume rotation along the forward kneading direction.
[0034] The decompression and reverse redistribution are performed in the following order: first decompression, then reverse rotation, and then re-pressure. That is, after the pressure cap is reduced to the decompression kneading pressure, the kneading disc rotates in the reverse redistribution direction, then resumes rotation in the forward kneading direction, and the pressure cap is restored to the target kneading pressure.
[0035] S4. After the applied pressure is restored to the target kneading pressure, the displacement changes of the current drive load and the cap are reacquired. Based on the increase of the current drive load relative to the reference drive load and the displacement change of the cap, it is determined whether the local compaction state has been released. If the local compaction state is released, the kneading continues at the current kneading pressure stage. If the local compaction state is not released, S3 is repeated. After the current kneading pressure stage reaches the corresponding preset kneading time, the process switches to the next kneading pressure stage until all kneading pressure stages are completed, and the kneaded tea leaves are obtained.
[0036] The determination of the release of local compaction status includes: after the pressure of the cap is restored to the target kneading pressure, the displacement change of the current driving load and the cap is reacquired within no less than two consecutive verification monitoring cycles; in each verification monitoring cycle, if the increase of the current driving load relative to the reference driving load is less than the load increment threshold, or if the displacement change of the cap is greater than the cap displacement threshold, the local compaction status is determined to be released.
[0037] The kneading pressure stage includes a first kneading pressure stage, a second kneading pressure stage, and a third kneading pressure stage executed sequentially; the target kneading pressure of the second kneading pressure stage is greater than the target kneading pressure of the first kneading pressure stage, and is also greater than the target kneading pressure of the third kneading pressure stage.
[0038] When the kneading pressure stage reaches the corresponding preset kneading time, it is determined whether the tea leaves to be kneaded are still in a locally compacted state; if the tea leaves to be kneaded are still in a locally compacted state, the kneading pressure stage is maintained and S3 is repeated; after the locally compacted state is released, the process switches to the next kneading pressure stage.
[0039] Example 2
[0040] like Figure 2 As shown, this embodiment, based on Embodiment 1, specifically explains the parameter settings, local compaction state determination, decompression and reverse redistribution, and re-pressurization verification process during the kneading pressure stage. Green tea leaves that have undergone fixation and cooling are used as the tea leaves to be kneaded, and a kneading machine equipped with a reversible kneading disc, an adjustable pressure cap, a drive motor torque acquisition module, and a cap displacement acquisition module is used for kneading.
[0041] The tea leaves to be rolled are placed into the rolling chamber, and the rolling process is divided into three sequential rolling pressure stages: a first rolling pressure stage, a second rolling pressure stage, and a third rolling pressure stage. The target rolling pressure for the first rolling pressure stage is 12 kPa, the reduced rolling pressure is 5 kPa, and the preset rolling time is 6 minutes. The target rolling pressure for the second rolling pressure stage is 20 kPa, the reduced rolling pressure is 8 kPa, and the preset rolling time is 10 minutes. The target rolling pressure for the third rolling pressure stage is 14 kPa, the reduced rolling pressure is 6 kPa, and the preset rolling time is 5 minutes. During the first, second, and third rolling pressure stages, the rotation speed of the rolling disc along the forward rolling direction is 18 r / min, 16 r / min, and 14 r / min, respectively.
[0042] After each kneading pressure stage begins, the pressure cap is controlled to apply the corresponding target kneading pressure. Once the actual applied pressure stabilizes, the output torque of the drive motor is continuously acquired over three benchmark monitoring cycles, with each cycle lasting 5 seconds. Specifically, the maximum value of the drive motor output torque within each benchmark monitoring cycle is acquired, and the arithmetic mean of the three maximum values is determined as the benchmark drive load for the corresponding kneading pressure stage. In subsequent monitoring cycles, the maximum value of the drive motor output torque within the corresponding monitoring cycle is determined as the current drive load, and the displacement increment of the pressure cap along the pressure direction is acquired within the same monitoring cycle.
[0043] In this embodiment, the load increment threshold is 20% of the reference drive load, and the cap displacement threshold is 1.5mm. When the increase of the current drive load relative to the reference drive load reaches 20% of the reference drive load in two consecutive monitoring cycles, and the displacement increment of the cap is not greater than 1.5mm, it is determined that the tea leaves to be kneaded are in a locally compacted state.
[0044] After determining that the tea leaves to be rolled are in a partially compacted state, the actual pressure applied by the pressure cap is reduced to the reduced rolling pressure of the corresponding rolling pressure stage. While maintaining the reduced rolling pressure, the rotation of the rolling disc in the forward rolling direction is stopped, and the disc is rotated in the reverse redistribution direction at a speed of 12 r / min until the cumulative reverse rotation reaches 3 revolutions. Subsequently, the reverse rotation of the rolling disc is stopped, and the disc is restored to the corresponding forward rolling direction, while the actual pressure applied by the pressure cap is restored to the target rolling pressure of the corresponding rolling pressure stage.
[0045] After the actual applied pressure returns to the target kneading pressure, the displacement increment of the current drive load and the gland is acquired in 5-second verification monitoring cycles. The local compaction state is considered released when at least one of the following conditions is met in each of two consecutive verification monitoring cycles: the increase in the current drive load relative to the reference drive load is less than 20% of the reference drive load; the displacement increment of the gland is greater than 1.5 mm. When the local compaction state is released, kneading continues at the corresponding kneading pressure stage; when the local compaction state is not released, the decompression, reverse redistribution, re-compression, and verification operations are repeated.
[0046] Each kneading pressure stage has a preset kneading time, which is the minimum execution time for that kneading pressure stage. When any kneading pressure stage reaches its preset kneading time, it is determined whether the tea leaves are still in a partially compacted state. If the partial compaction is relieved, the process switches to the next kneading pressure stage. If the partial compaction is not relieved, the kneading pressure stage is maintained, and the decompression, reverse redistribution, re-compression, and verification operations are repeated until the partial compaction is relieved. After completing the third kneading pressure stage, the pressure applied by the cap is released, and the kneaded tea leaves are obtained.
[0047] Example 3
[0048] This embodiment adjusts the number of kneading pressure stages based on Embodiment 1. The tea leaves to be kneaded are placed into the kneading chamber of the kneading machine, and the kneading process is divided into a first kneading pressure stage and a second kneading pressure stage, executed sequentially. The target kneading pressure of the first kneading pressure stage is lower than the target kneading pressure of the second kneading pressure stage. Each kneading pressure stage is respectively set with a reduced kneading pressure, a load increment threshold, a cap displacement threshold, and a preset kneading duration. The reduced kneading pressure is lower than the target kneading pressure of the corresponding kneading pressure stage.
[0049] During both the first and second kneading pressure stages, the pressure cap is controlled to apply pressure to the tea leaves to be kneaded at the corresponding target kneading pressure, and the kneading disc is controlled to rotate in the forward kneading direction. When it is determined, based on the increase in the current drive load relative to the reference drive load and the displacement change of the pressure cap, that the tea leaves to be kneaded are in a locally compacted state, the pressure cap is controlled to decrease to the corresponding reduced kneading pressure, and the kneading disc is controlled to rotate in the reverse redistribution direction. Subsequently, the forward kneading rotation and the target kneading pressure are restored. After re-pressing, it is further determined, based on the current drive load and the displacement change of the pressure cap, whether the locally compacted state has been resolved. If the locally compacted state has been resolved, the current kneading pressure stage continues or the process switches to the next kneading pressure stage.
[0050] This embodiment shows that the local compaction identification, decompression reverse redistribution, and re-compression verification control method of the present invention is not limited to three kneading pressure stages, but can also be applied to the tea kneading process with two kneading pressure stages.
[0051] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.
Claims
1. A method for intermittent, variable-pressure, segmented tea rolling, characterized in that, include: S1. Put the tea leaves to be kneaded into the kneading chamber of the kneading machine, and divide the kneading process into at least two kneading pressure stages executed sequentially; For each of the aforementioned kneading pressure stages, a target kneading pressure, a reduced kneading pressure, a load increment threshold, and a cap displacement threshold are set. The target kneading pressures of adjacent kneading pressure stages are different, and the reduced kneading pressure is less than the target kneading pressure of the corresponding kneading pressure stage. S2. During the current kneading pressure stage, control the pressure cap to apply pressure to the tea leaves to be kneaded with the corresponding target kneading pressure, and control the kneading disc to rotate in the forward kneading direction; after the target kneading pressure stabilizes, obtain the reference drive load of the kneading drive mechanism, and obtain the current drive load and the displacement change of the pressure cap in the pressure direction in subsequent monitoring cycles; S3. When, within the same monitoring cycle, the increase in the current driving load relative to the reference driving load reaches the load increment threshold, and the displacement change of the pressure cap is not greater than the pressure cap displacement threshold, it is determined that the tea leaves to be kneaded are in a locally compacted state; in response to the locally compacted state, the pressure applied by the pressure cap is controlled to decrease from the target kneading pressure to the reduced kneading pressure, and the kneading disc is controlled to switch from the forward kneading direction to the reverse redistribution direction; after the reverse rotation is completed, the kneading disc is controlled to resume rotation along the forward kneading direction, and the pressure applied by the pressure cap is restored to the target kneading pressure; S4. After the applied pressure is restored to the target kneading pressure, the displacement changes of the current driving load and the cap are reacquired, and the local compaction state is determined based on the increase of the current driving load relative to the reference driving load and the displacement change of the cap. When the local compaction state is released, kneading continues at the current kneading pressure stage. When the local compaction state is not released, S3 is repeated. After the current kneading pressure stage reaches the corresponding preset kneading time, the process switches to the next kneading pressure stage until all kneading pressure stages are completed, and the kneaded tea leaves are obtained.
2. The intermittent variable pressure segmented tea rolling method according to claim 1, characterized in that: The kneading drive mechanism includes a drive motor that drives the kneading disc to rotate, and the current drive load is the output torque of the drive motor; the displacement change of the pressure cap is collected by a linear displacement sensor set on the lifting path of the pressure cap.
3. The intermittent variable pressure segmented tea rolling method according to claim 2, characterized in that: The reference drive load is the arithmetic average of the output torque of the drive motor collected during three consecutive reference monitoring cycles in which the pressure cap maintains the target kneading pressure; the current drive load is the maximum value of the output torque of the drive motor in the corresponding monitoring cycle.
4. The intermittent variable pressure segmented tea rolling method according to claim 1, characterized in that: The determination of the local compaction state includes: within at least two consecutive monitoring cycles, the increase of the current driving load relative to the reference driving load reaches the load increment threshold, and the displacement change of the cap does not exceed the cap displacement threshold.
5. The intermittent variable pressure segmented tea rolling method according to claim 1, characterized in that: The method of controlling the kneading disc to switch from the forward kneading direction to the reverse redistribution direction includes: stopping the rotation of the kneading disc along the forward kneading direction, and then controlling the kneading disc to rotate along the reverse redistribution direction, which is opposite to the forward kneading direction; during the rotation of the kneading disc along the reverse redistribution direction, the pressure cap maintains the reduced kneading pressure; when the cumulative number of reverse rotations of the kneading disc reaches a preset number of reverse rotations, stopping the reverse rotation of the kneading disc, and controlling the kneading disc to resume rotation along the forward kneading direction.
6. The intermittent variable pressure segmented tea rolling method according to claim 1, characterized in that: The determination of the release of the local compaction state includes: after the pressure applied by the cap returns to the target kneading pressure, the displacement change of the current driving load and the cap is reacquired within at least two consecutive verification monitoring cycles; in each verification monitoring cycle, if the increase of the current driving load relative to the reference driving load is less than the load increment threshold, or if the displacement change of the cap is greater than the cap displacement threshold, the local compaction state is determined to be released.
7. The intermittent variable pressure segmented tea rolling method according to claim 1, characterized in that: The kneading pressure stage includes a first kneading pressure stage, a second kneading pressure stage, and a third kneading pressure stage executed sequentially; the target kneading pressure of the second kneading pressure stage is greater than the target kneading pressure of the first kneading pressure stage, and is also greater than the target kneading pressure of the third kneading pressure stage.
8. The intermittent variable pressure segmented tea rolling method according to claim 1, characterized in that: When the kneading pressure stage reaches the corresponding preset kneading time, it is determined whether the tea leaves to be kneaded are still in the local compaction state; if the tea leaves to be kneaded are still in the local compaction state, the kneading pressure stage is maintained and S3 is repeated; after the local compaction state is released, the process switches to the next kneading pressure stage.