Mold exhaust device for vulcanization forming of rubber track and vulcanization forming method

Abstract

The invention relates to the technical field of rubber track preparation, in particular to a mold exhaust device for vulcanization forming of a rubber track and a vulcanization forming method. Micro-roughness exhaust belts are arranged in easy air trapping areas such as iron teeth, smooth and clean sealing spigots are arranged in the circumferential direction, and shallow exhaust buffer grooves / annular grooves are formed in parting surfaces; the roughness gradient, the step isolation belt and the staggered seam allowance can be selected to form a labyrinth type microgap channel. According to the structure, trapped gas is directionally guided and discharged through the surface tension / capillary action, rubber columns, hole blocking and shutdown are avoided, bubbles, scorching marks and flashes are remarkably reduced, the maintenance time is shortened, the vulcanization stability is improved, the qualification rate is increased, and the structure is suitable for the thick-rubber deep-tooth crawler belt mold.

Description

Technical Field

[0001] This invention relates to the field of rubber track manufacturing technology, and in particular to a mold venting device and a vulcanization molding method for rubber track vulcanization molding. Background Technology

[0002] During the vulcanization process of rubber tracks, unvulcanized rubber material traps air within the mold cavity during mold closing and filling stages, creating trapped air. If venting is inadequate, defects such as air bubbles, insufficient rubber, burn marks, and surface imperfections often occur, especially at complex geometric locations such as the root radius of the tooth, sharp transition areas, and rib intersections. To address this problem, the industry commonly employs methods such as parting surface venting grooves, through-hole venting, microporous venting plugs, and introducing microstructures or textures onto the mold cavity surface. However, each solution still presents a trade-off between venting efficiency, maintenance costs, and product appearance.

[0003] Firstly, parting surface venting channels are one of the most common solutions. Chinese patent CN204109288U discloses a mold with stepped venting channels: a two-stage structure of an anti-overflow section and an venting section is set at the end of the parting surface. The typical dimensions are that the anti-overflow section is 0.05-0.07 mm deep and the venting section is 0.15-0.20 mm deep, and it is connected to the outside through the end vent hole to balance preventing glue leakage and venting efficiency. In addition, Chinese patent CN206317314U proposes to set a flat-bottomed notch at the sealing position of the parting surface and extend it outward into a sloping notch with its depth gradually increasing in the outward direction to improve the continuity of the venting channel in the parting surface direction. Another Chinese patent CN206383450U expands the coverage of parting surface venting by forming a curved venting network around the cavity by connecting the main flow channel and multiple branch flow channels. While this type of method is simple to implement, relying solely on the parting surface channel in air pocket locations such as thick rubber areas or deep cavities of iron teeth may still result in insufficient exhaust paths in the near cavity section, sensitivity to parting surface machining tolerances and assembly coaxiality, and the risk of parting surface marks / flashes under high-pressure molding.

[0004] Secondly, using through-holes / ventilated components to directly connect the mold cavity to the outside is also a common approach. Chinese patents CN100343033C and CN100343034C propose setting microporous ventilated components and micro-venting slits on the working surface of the mold cavity, along with venting grooves connected to them, thereby achieving direct venting from the working surface in molds for rubber, plastics, etc. For tires and large plastic parts, microporous vent plugs made of sintered porous materials have also emerged. For example, Chinese patent CN2385862Y provides examples of pore diameter, size, and material for different product scenarios to improve venting capacity and reduce surface defects. However, common pain points of through-hole / ventilated component solutions in the rubber product field are: they are prone to forming glue pillars during demolding and being pulled apart, which can easily lead to pore blockage later; the channels of porous components are easily contaminated under long-term hot pressing and formulation precipitates, requiring frequent disassembly and cleaning or replacement, resulting in high maintenance costs; at the same time, the orifice or insert boundary may have an adverse effect on appearance and stress continuity.

[0005] Thirdly, the use of microstructures and textures on the cavity surface to improve mold filling flow and promote gas escape along the surface is also gradually being applied to tire / rubber molds. Taking Chinese patent CN102248616A as an example, it sets micro-protrusions on the forming surface of a tire mold to form a rough-surface forming part, providing a quantitative range of 10–300 μm for the protrusion height, and pointing out that this rough surface can form a flow path along the circumference that facilitates air exhaust, thereby suppressing poor bonding and appearance defects caused by residual air. This approach demonstrates that the idea of ​​controlling surface roughness or texture to form microscale ventilation channels is known, but existing disclosures mostly focus on the uniformity of pattern appearance and general flow improvement. Disclosures regarding directional venting design for deep cavities such as track teeth, the coupling relationship with parting surface microgrooves, and engineering windows that avoid long-term maintenance-free operation after through-holes are still relatively limited.

[0006] In summary, existing technologies offer various methods for constructing venting paths: shallow grooves / network channels on the parting surface, through-holes or ventilated inserts, and guiding gas flow along the surface through surface microtextures. However, for track molds, which are characterized by thick rubber, deep teeth, and numerous local dead angles, challenges remain: ① how to continuously connect the micro-scale channels near the cavity with the parting surface channels; ② how to suppress the chain reaction of glue pillars—hole blockage—downtime cleaning without using through-holes; ③ how to quantify the process window that balances a flawless appearance, stable venting, and low maintenance. Therefore, it is still necessary to propose a venting structure that collaboratively designs controllable roughness channels on the cavity surface, parting surface buffer grooves, and sealing stop areas to meet the venting needs of complex parts of track molds and reduce maintenance frequency. Summary of the Invention

[0007] This invention aims to solve the problems of air trapping in complex deep cavities such as iron teeth in track molds, and the formation of glue columns and blockage of venting holes, leading to frequent cleaning and product defects. It proposes a mold venting device for vulcanization molding of rubber tracks. This device uses a cavity micro-roughness venting band, parting surface buffer groove, and smooth sealing stop to form a holeless venting structure, which realizes a stable, efficient and low-maintenance venting channel, reduces scorch marks / insufficient glue and appearance marks, and improves the pass rate and production efficiency.

[0008] To achieve the above objectives, the present invention adopts the following technical solution: A mold venting device for vulcanizing rubber tracks includes an upper mold and a lower mold arranged opposite each other, forming a tooth cavity and a tread cavity together, and a venting area located between the cavity and the parting surface. The venting area is machined on at least one side of the mold cavity surface into a micro-roughness venting band extending from the cavity to the parting surface. The surface roughness of the venting band satisfies Rz = 15-60 μm and Ra = 1.0-5.0 μm. The venting band is circumferentially surrounded by a smooth sealing stop area, the surface roughness of which Ra ≤ 0.4 μm. A parting surface venting buffer groove is provided at the outer end of the venting band at the parting surface, the buffer groove having a depth of 0.03-0.15 mm and a width of 0.5-2.0 mm. No through-hole venting device penetrating the mold body is provided in the tooth cavity and its adjacent area.

[0009] Preferably, the micro-roughness exhaust strip is formed by a composite process of discharge texturing, fine wire electrical discharge, sandblasting or shot peening, and the micro-groove array has a groove width of 10-50 μm, a groove depth of 10-40 μm, and a pitch of 50-200 μm.

[0010] Preferably, the micro-roughness venting band is arranged radially from the tip, root fillet and side wall corner of the tooth cavity towards the parting surface, and there is a roughness gradient along the venting direction, that is, Ra is 1.0 to 2.0 μm near the cavity end and gradually transitions to Ra of 3.0 to 5.0 μm towards the parting surface.

[0011] Preferably, the effective width W of the venting strip in the width direction is 2 to 6 mm, and smooth stop rings with a width of 0.3 to 1.0 mm are provided on both sides to restrict molten rubber from entering the venting strip.

[0012] Preferably, the parting surface venting buffer groove is connected to a circumferentially connected annular venting groove with a depth of 0.03-0.10 mm and a width of 0.8-1.5 mm, so as to maintain a stable micro-gap venting path under the action of mold closing pressure.

[0013] Preferably, a replaceable exhaust insert is provided at the top of the iron tooth or in the transition area between the bolt hole and the reinforcing rib. The molding surface of the insert is pre-made with micro-textures consistent with the parameters of the exhaust belt, and quick disassembly and assembly are achieved through a positioning cone or positioning pin for maintenance.

[0014] Preferably, the upper and lower molds are staggered at the venting zone: a slightly rough venting zone is provided on one side, and a smooth sealing stop area is provided on the other side. Together, they form a labyrinthine micro-gap channel to reduce the risk of imprinting on the product surface.

[0015] Preferably, a stepped isolation strip with a height of 0.05 to 0.20 mm is provided between the exhaust strip and the toothed cavity. The isolation strip has a smooth surface and is used to trap a small amount of adhesive material entering the edge of the exhaust strip and prevent its further diffusion.

[0016] Preferably, the exhaust strip is arranged at the front and rear edges of the track in the direction of travel, the R-angle area at the root of the tooth, and the turning area of ​​the tread groove. The total area of ​​the exhaust strip accounts for 0.5% to 4% of the projected area of ​​the mold cavity.

[0017] Furthermore, the present invention also provides a method for vulcanizing rubber tracks using the exhaust device, comprising: S1) Process micro-roughness venting strips in the areas of the upper and lower molds that require venting and open buffer grooves on the parting surface; S2) Close the mold and inject or press uncured rubber, with a mold closing pressure of 10-25 MPa; S3) During the vulcanization process, the trapped gas is discharged through the microchannels of the exhaust belt and the buffer groove of the parting surface; S4) After vulcanization, the mold is opened and the product is demolded. Since there are no through-hole venting rubber pillars, the venting strip only needs to be wiped or lightly cleaned by sandblasting before entering the next cycle.

[0018] This invention, by employing the aforementioned technical solution, constructs a synergistic channel of micro-roughness venting band, smooth sealing stop, and parting surface buffer groove in the iron teeth and their adjacent areas. Surface tension / capillary drive is used to directionally migrate the trapped gas along the micro-channels on the mold surface and release it in a stable state at the parting surface. This avoids the breakage of glue columns and chain-like failures caused by through-holes, while also suppressing flash and surface imprints on the parting surface. The roughness gradient and stepped isolation band further weaken the intrusion of molten glue into the venting band, maintaining the long-term unobstructed venting channel. The annular connecting groove provides pressure equalization and flow guidance, improving the uniformity of venting at deep cavities, sharp tops, and R-corners, thereby reducing scorch marks, bubbles, and insufficient glue, and improving the appearance and dimensional consistency of the product. Replaceable inserts facilitate rapid maintenance, significantly reducing cleaning frequency and downtime, and improving vulcanization stability and production line efficiency. Attached Figure Description

[0019] Figure 1 , Figure 2This is a schematic diagram of the structure of an existing vulcanizing mold.

[0020] Figure 3 , Figure 4 This is a schematic diagram of the vulcanizing mold of the present invention. Detailed Implementation

[0021] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present invention.

[0022] like Figure 1 , Figure 2 As shown, traditional track tooth molds typically have through holes on the top surface or near the side wall of the tooth for venting. During demolding, these holes are prone to forming and breaking off venting rubber columns. In subsequent production stages, the through holes become blocked by rubber residue, resulting in poor venting and frequent maintenance.

[0023] like Figure 3 , Figure 4 As shown, the mold venting structure of the present invention includes: a tooth-shaped cavity 3 and a tread-shaped cavity jointly formed by the upper mold 1 and the lower mold 2; a micro-roughness venting band 4 located near the transition area from the cavity to the parting surface; a smooth sealing stop area 5 surrounding the venting band; and a parting surface venting buffer groove 6 connected to the outside at the parting surface, and an annular connecting groove 7 may be arranged circumferentially thereon if necessary. The tooth-shaped cavity and its adjacent areas do not have through-hole venting.

[0024] Micro-roughness venting band 4: forms a micron-level connecting channel near the cavity, guiding trapped gas to migrate directionally along the mold surface to the parting surface. Its surface roughness is preferably Rz = 15~60μm, Ra = 1.0~5.0μm, and the effective width W of the venting band is 2~6mm.

[0025] Smooth sealing stop area 5: A sealing edge is formed around the venting strip to restrict molten rubber from entering the venting strip and reduce visible imprints. Its surface roughness Ra≤0.4μm, and preferably, smooth narrow rings of 0.3~1.0mm are set on both sides as secondary seals.

[0026] Parting surface exhaust buffer groove 6: Connects to the outer end of the exhaust belt, used to stabilize pressure and collect gas escaping from the microchannel, with typical dimensions of 0.03-0.15mm depth and 0.5-2.0mm width; when it is necessary to expand the coverage area, the buffer groove can be connected to the annular connecting groove 7 (0.03-0.10mm depth and 0.8-1.5mm width).

[0027] Furthermore, to address the issue of "air pockets" easily forming at the tip, root radius, and sidewall corners of the tooth, exhaust bands 4 are arranged from the inside out in these areas, directing them towards the parting surface along the shortest gas escape path. Tip area: Starting from the center of the tooth tip, 1 to 2 venting bands are arranged along the tooth height direction, and the end point connects with the parting surface buffer groove 6; Root R-corner area: A "fan-shaped" exhaust strip is arranged tangentially along the R-corner, and a buffer groove 6 is drawn into the cavity-parting surface transition area; Side wall corner area: An exhaust strip is arranged in the direction of the bisector of the angle between two adjacent walls to shorten the exhaust distance in the near cavity section.

[0028] The above layout allows the gas to be preferentially "extracted" from the deep corners of the cavity during the vulcanization pressurization stage, reducing scorch marks and insufficient adhesive.

[0029] Furthermore, to balance venting efficiency and suppressing glue leakage, the venting zone 4 employs a roughness gradient that gradually increases from the cavity to the parting surface: Ra is 1.0–2.0 μm near the cavity end, transitioning to Ra of 3.0–5.0 μm towards the parting surface, allowing gas to migrate directionally under the combined action of pressure gradient and surface tension. A stepped isolation zone 8 (0.05–0.20 mm high, smooth surface) is set at the adjacent boundary between the venting zone and the toothed cavity to trap a small amount of glue entering the edge and prevent its further diffusion along the venting zone, maintaining the long-term unobstructed flow of the microchannel.

[0030] Furthermore, to reduce sensitivity to unilateral machining errors, the upper and lower molds are staggered at corresponding positions: one side has a micro-roughness venting zone 4, and the other side has a smooth stop zone 5. When the two sides are opposite each other, they form a "maze-like" micro-gap path in the mold-closed state, which not only improves the resistance to glue leakage in the near parting surface section, but also expands the effective coverage of the venting zone, without significantly increasing the risk of appearance imprints.

[0031] Furthermore, replaceable venting inserts 9 are installed on the top surface of the iron teeth, the area where the reinforcing ribs meet, and near the bolt holes. The working surface of these inserts has pre-fabricated micro-texture parameters consistent with the venting strip, and they are positioned and secured using positioning cones / pins 10 and countersunk screws. This structure facilitates: 1) rapid insert replacement when there is significant localized carbon buildup or formulation precipitates, reducing downtime; 2) rapid parameter adjustment by replacing inserts with different texture parameters when switching between different formulations / specifications; and 3) maintaining consistency in the parting surface stop area 5 after mold repair and polishing. Routine maintenance only requires wiping or low-pressure sandblasting of the venting strip area to restore channel cleanliness.

[0032] The roughness window of this invention, Rz = 15–60 μm and Ra = 1.0–5.0 μm, achieves a balance between venting efficiency and appearance. When the viscosity of the rubber compound is low or the mold temperature is high, the lower limit of Ra (approximately 1.0–2.0 μm) is preferred, and the width of the stop should be increased. When the geometry is more complex and the air trapping is heavier, the upper limit of Ra can be appropriately increased, and the width of the buffer groove can be increased. The total projected area of ​​the venting zone should preferably account for 0.5%–4% of the projected area of ​​the mold cavity; sharp points / roots are preferred, followed by complex intersection areas, and the number of venting zones should be reduced on flat surfaces to reduce appearance risks. The venting zone has a significant impact on preventing rubber leakage and inhibiting rubber intrusion, and staggered stops and stepped isolation zones are recommended as a preferred combination of features.

[0033] The manufacturing process and dimensional control of the above structure are as follows: 1) Base material and heat treatment: The mold body can be made of common mold steels such as P20, H13 or Cr12MoV, and is rough machined according to the product specifications and then tempered / quenched and tempered. 2) Smooth stop machining: The stop area 5 of the parting surface is precision milled, ground and polished to achieve Ra≤0.4μm; the width of the stop and its relative position with the venting zone are controlled by the reference pin hole; 3) Microtexturing: The exhaust zone 4 can be textured by fine wire electrical discharge machining (EDM), fine sandblasting or shot peening / laser texturing, etc.; preferably, the base surface is first sandblasted and then the micro-grooves are oriented and etched by fine wire EDM to obtain an array with a groove width of 10-50 μm, a groove depth of 10-40 μm and a pitch of 50-200 μm.

[0034] 4) Buffer groove and annular groove: A buffer groove 6 with a depth of 0.03 to 0.15 mm is machined in one clamping at the parting surface. If necessary, an annular groove 7 with a depth of 0.03 to 0.10 mm is added to ensure smooth connection with the end of the exhaust belt.

[0035] 5) Assembly and inspection: Perform blue oil inspection based on the parting surface to ensure that the fit rate of the stop area is ≥90%; conduct air flow or color developer penetration test on the connectivity of the exhaust strip and buffer groove to confirm that there are no dead corners or local blockages.

[0036] The vulcanization process and control procedures for rubber tracks are as follows: (1) After mold closing, pre-pressing is performed to confirm the sealing of the parting surface stop area 5; (2) Inject or press uncured rubber, preferably with a mold closing pressure of 10-25 MPa; (3) During the heating and vulcanization stage, the microchannels in the exhaust belt 4 form a stable gas release path under the action of mold closing pressure, capillary and surface tension. The gas is discharged outside the mold after being collected by the buffer groove 6 and the ring groove 7. (4) Demolding: Since there are no through holes, there is no glue residue on the demolding surface. The venting belt 4 only needs to be wiped regularly before entering the next cycle. For formulations containing plasticizers or prone to exudation of raw gum, it is recommended to sweep sand or wipe with alcohol once per shift to keep the channel clean.

[0037] Application Examples I. Samples and molds Product target: Rubber tracks with a width of 230mm, a pitch of 72mm, and a tooth height of 45mm. They are single-mold double-cavity tracks with reinforcing ribs and transition R-angles on both sides of the iron teeth.

[0038] Rubber compound information: natural rubber / styrene-butadiene rubber blend; ML(1+4) 100℃ = 65±3; Shore A hardness = 65±2; contains wax and aromatic oil, total plasticizer 12-16 phr; conventional vulcanization system.

[0039] Vulcanization conditions: mold temperature 155±2℃; mold closing pressure 18MPa; holding pressure for 18min; pre-mold closing with low pressure for 3s (to facilitate initial venting); consistent demolding spray.

[0040] II. Comparative Examples and Implementation Structural Comparative Example 1 (Traditional through-hole venting): The top surface and root of the iron tooth are each provided with a through hole of φ0.8-1.0mm. The parting surface has no annular buffer groove, only shallow scratch-like venting marks of 0.02-0.05mm. The remaining mold surfaces have Ra≤0.8μm (conventional polishing).

[0041] Example 1 (Structure of the Invention): A micro-roughness venting zone is set near the cavity: Rz = 20-50μm, Ra gradient from the cavity to the parting surface 1.5→4.0μm; effective width W = 4mm; The exhaust strip has smooth sealing stop areas on both sides: Ra≤0.4μm, narrow ring width 0.6mm; A buffer groove is provided on the parting surface: 0.08mm deep and 1.0mm wide, and it connects with a circumferential annular connecting groove (0.05mm×1.2mm); The upper and lower molds are staggered at corresponding locations (one side is the venting strip, and the other side is the stop), and a stepped isolation strip with a height of 0.10mm is arranged on the inner edge of the venting strip; no through holes are provided.

[0042] Exhaust band coverage area: 1 line along the center line of each tooth tip, 2 lines along the root radius fan-shaped area, and 1 line along the bisector of the included angle of each side wall; total area = 2.1% of the mold cavity projected area.

[0043] III. Testing Methods and Evaluation Indicators Sample size and grouping: Comparative Example 1 and Example 1 each had n = 2,000 units produced continuously (4 shifts × 500 units / shift).

[0044] Appearance defect rate: Any presence of bubbles / burnt marks / insufficient glue results in disqualification; statistics are based on online visual inspection combined with manual verification (threshold: bubble diameter ≥ 1mm or burnt area ≥ 10mm). 2 ).

[0045] "Glue pillars, hole blockage" incidents: 1 instance of glue pillars forming and breaking during demolding; or 1 instance of unplanned machine stoppage for hole cleaning / disassembly and cleaning due to poor venting.

[0046] Downtime for maintenance: The total number of minutes of maintenance per shift caused by exhaust issues.

[0047] Surface imprint level: 0-5 (0 means no visible imprint, 5 means obvious imprint), and the median is calculated by randomly selecting 30 pieces from each shift.

[0048] Vulcanization cycle stability: mean cycle time per piece ± standard deviation (min).

[0049] Connectivity verification: After each shift, perform blue oil penetration and low-pressure gas testing (0.02MPa) on representative mold cavities and record the length of the connected path and the number of blockage points.

[0050] IV. Results and Data

[0051] Statistical explanation: Appearance defect rate is expressed as χ² 2 The test p < 0.01; the periodic stability was tested by t-test and p < 0.05. Blue oil / gas test showed that the comparative example often had single-point blockage in the near cavity section after 300-600 consecutive pieces; the example showed that after 2,000 pieces, the exhaust band-buffer channel remained continuous, with only slight edge contamination, which could be restored by routine wiping.

[0052] The foregoing description of embodiments of the present invention, through which those skilled in the art are able to implement or use the present invention, will be readily apparent to those skilled in the art. Various modifications to these embodiments will be readily apparent to those skilled in the art. The general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the present invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novelty disclosed herein.

Claims

1. A mold venting device for vulcanizing rubber tracks, comprising an upper mold and a lower mold arranged opposite to each other, a toothed cavity and a tread cavity formed therebetween, and a venting area located between the cavity and the parting surface, characterized in that: The venting area is processed on at least one side of the mold cavity surface into a micro-roughness venting band extending along the cavity towards the parting surface, wherein the surface roughness of the venting band satisfies Rz = 15~60μm and Ra = 1.0~5.0μm; The exhaust strip is circumferentially surrounded by a smooth sealing stop area, and the surface roughness Ra of the stop area is ≤0.4μm; A parting surface venting buffer groove is provided at the outer end of the venting strip at the parting surface. The depth of the buffer groove is 0.03-0.15mm and the width is 0.5-2.0mm. Furthermore, no through holes penetrating the mold body are provided in the iron tooth cavity and its adjacent areas.

2. The mold venting device according to claim 1, characterized in that, The micro-roughness exhaust strip is formed by a composite process of discharge texturing, fine wire electrical discharge, sandblasting or shot peening, and the micro-groove array has a groove width of 10-50 μm, a groove depth of 10-40 μm, and a pitch of 50-200 μm.

3. The mold venting device according to claim 1, characterized in that, The micro-roughness venting band is arranged radially from the tip, root fillet and side wall corner of the tooth cavity towards the parting surface, and there is a roughness gradient along the venting direction, that is, Ra is 1.0 to 2.0 μm near the cavity end and gradually transitions to Ra of 3.0 to 5.0 μm towards the parting surface.

4. The mold venting device according to claim 1, characterized in that, The effective width W of the venting strip is 2 to 6 mm in the width direction, and smooth stop rings with a width of 0.3 to 1.0 mm are provided on both sides to restrict molten rubber from entering the venting strip.

5. The mold venting device according to claim 1, characterized in that, The parting surface venting buffer groove is connected to the circumferentially connected annular venting groove. The groove has a depth of 0.03-0.10 mm and a width of 0.8-1.5 mm to maintain a stable micro-gap venting path under the action of mold closing pressure.

6. The mold venting device according to claim 1, characterized in that, Replaceable exhaust inserts are provided at the top of the iron teeth or in the transition area of ​​the bolt holes and reinforcing ribs. The molded surface of the inserts is pre-textured with micro-textures consistent with the parameters of the exhaust belt, and can be quickly disassembled and installed for maintenance by means of positioning cones or positioning pins.

7. The mold venting device according to claim 1, characterized in that, The upper and lower molds are staggered at the venting zone: a slightly rough venting zone is set on one side, and a smooth sealing stop area is set on the corresponding position on the other side. Together, they form a labyrinthine micro-gap channel to reduce the risk of imprinting on the product surface.

8. The mold venting device according to claim 1, characterized in that, A stepped isolation strip with a height of 0.05 to 0.20 mm is set between the exhaust strip and the toothed cavity. The isolation strip has a smooth surface and is used to trap a small amount of adhesive material entering the edge of the exhaust strip and prevent it from spreading further.

9. The mold venting device according to claim 1, characterized in that, The exhaust strip is preferably arranged at the front and rear edges of the track in the direction of travel, the R-angle area at the root of the iron tooth, and the turning area of ​​the tread groove. The total area of ​​the exhaust strip accounts for 0.5% to 4% of the projected area of ​​the mold cavity.

10. A method for vulcanizing rubber tracks using the exhaust device according to any one of claims 1 to 9, characterized in that, include: S1) Process micro-roughness venting strips in the areas of the upper and lower molds that require venting and open buffer grooves on the parting surface; S2) Close the mold and inject or press uncured rubber, with a mold closing pressure of 10-25 MPa; S3) During the vulcanization process, the trapped gas is discharged through the microchannels of the exhaust belt and the buffer groove of the parting surface; S4) After vulcanization, the mold is opened and the product is demolded. Since there are no through-hole venting rubber pillars, the venting strip only needs to be wiped or lightly cleaned by sandblasting before entering the next cycle.

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