Tire vulcanization control method

Abstract

The invention relates to a tire vulcanization control method which is used for a tire vulcanization system, and for a segmented mold and a capsule on each side, the vulcanization system comprises a shaping nitrogen inlet pipe connected to the steam inlet end of the capsule and a shaping nitrogen exhaust pipeline connected to the exhaust end of the capsule. The method comprises the following steps: primary shaping: controlling shaping nitrogen to enter a capsule through a shaping nitrogen inlet pipe until a preset first initial shaping pressure is reached; and the segmented mold is controlled to be closed, the shaping discharge pressure P < discharge > is determined in real time in the mold closing process, part of shaping nitrogen is controlled to be discharged from the shaping nitrogen discharge pipeline in the mold closing process, and the discharge amount is determined based on the real-time shaping discharge pressure P < discharge >. According to the scheme, in the mold closing process of the one-time shaping stage, the shaping pressure in the mold cavity is automatically adjusted according to the volume change of the mold cavity, and the problem that the shaping pressure is too high in the mold closing process is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of tire vulcanization, and in particular to a tire vulcanization system and a control method. Background Art

[0002] Traditional tire vulcanization mainly uses steam + nitrogen vulcanization process, which mainly includes the following steps:

[0003] 1. Shaping: Open the shaping valve, control the shaping nitrogen to fill into the tire bladder at the process pressure, and shape the tire embryo;

[0004] 2. High-temperature steam inlet: Open the high-temperature steam inlet valve to control the high-temperature and high-pressure steam to fill the tire bladder so that the bladder temperature reaches the temperature required by the process;

[0005] 3. High-pressure nitrogen inlet: Open the high-pressure nitrogen inlet valve and control the high-pressure nitrogen to fill the tire bladder so that the internal pressure of the bladder reaches the pressure required by the process;

[0006] 4. Nitrogen recovery: After the vulcanization is completed, open the nitrogen recovery valve to recover the nitrogen;

[0007] 5. Drain: Open the drain valve to drain the remaining gas and condensed water in the system;

[0008] 6. Vacuuming: Open the vacuum valve and evacuate the system to a vacuum.

[0009] The piping system in the vulcanizer includes multiple air inlet and exhaust pipelines and multiple solenoid valves such as shaping valves, high-temperature steam inlet valves, high-pressure nitrogen inlet valves, nitrogen recovery valves, exhaust valves and vacuum valves installed on these pipelines. The above steps are implemented through the cooperation of the piping system.

[0010] Figure 1The diagram of the pipeline system used in the prior art is used for dual-mode tire vulcanization, and simultaneously controls the left and right flexible molds and the left and right capsules used in conjunction with the flexible molds on both sides. The steam inlet ends of the left capsule and the right capsule are respectively connected to a shaping nitrogen inlet pipe (about 0.2Mpa), and a first connecting pipeline is provided between the steam inlet ends of the left capsule and the right capsule. The bottom ends of the first connecting pipeline are respectively connected to a high-temperature steam inlet pipe (about 200°C, pressure 1.7Mpa), a high-pressure nitrogen inlet pipe (about 2.5Mpa), a main exhaust pipeline and a vacuum pipe; a second connecting pipeline is provided between the discharge ends of the left capsule and the right capsule, and the bottom ends of the second connecting pipeline are respectively connected to a nitrogen recovery pipe, a steam condensation pipe, a shaping exhaust pipe and a vacuum pipe. The above pipeline is provided with a vacuum pump on the inlet side and the discharge side, respectively. When the vulcanization is completed and the vacuum pumping step is performed, the inlet and discharge sides are vacuumed at the same time to speed up the vacuum pumping speed. A main exhaust pipeline is set on the inlet side and the exhaust side to exhaust the remaining gas on the inlet side and the exhaust side. The remaining pipelines on the inlet side and the return side are single-channel pipelines.

[0011] like Figure 2-4 As shown, when the above pipeline system is used for dual-mode tire vulcanization, the following problems are found in actual use:

[0012] Problem 1: The temperature difference between the left and right molds during the high-pressure steam filling stage is >5°C;

[0013] Question 2: The temperature difference between the left and right molds after vulcanization is >30°C;

[0014] Problem 3: The left and right mold pressures cannot be controlled separately during the pressure holding stage (poor pressure holding on one side affects the other side);

[0015] Problem 4: The instantaneous pressure from the first shaping to the mold closing process is too high and uncontrolled (0.03-0.20MPa);

[0016] Question 5: There is water accumulation at the lowest point of the bottom of the internal bladder on one side (there is a large temperature difference between the lowest point of the inner lining layer and the highest point of the left and right molds, resulting in a large temperature difference between the inner surfaces of the upper and lower sidewalls).

[0017] After analysis, the technicians found that the main reasons for the above problems are:

[0018] 1. The problem of temperature difference inside the mold and water accumulation at the bottom of one-sided capsule is mainly due to the fact that there is only one steam condensate drain pipe on the left and right molds, and the lengths of condensate drain on the left and right molds are different, resulting in different condensate draining effects and draining times on the capsules on both sides, leading to internal temperature differences (problems 1, 2, and 5).

[0019] 2. Since there is a connecting pipe between the discharge ends of the left and right capsules, during the pressure holding stage, if the discharge pipe of one side of the capsule leaks, it will cause leakage on the other side. Ultimately, the tires on both sides will have a poor pass rate due to insufficient pressure holding (Problem 3).

[0020] Regarding the above-mentioned question 4, the vulcanization system in the prior art usually includes two stages in the shaping step, namely, the primary shaping and the secondary shaping. During the primary shaping and mold closing, if the shaping pressure is too low, it is easy to cause unevenness in the tire. The problem of too low shaping pressure can be solved by increasing the shaping pressure. However, if the shaping pressure is increased, the internal pressure will increase instantly during the mold closing process, which will cause the instantaneous internal pressure in the mold closing process to be too high (the instantaneous pressure from the primary shaping to the mold closing process is too high and the uncontrolled pressure is between 0.03-0.20MPa), which is easy to cause problems such as tire arch, shoulder cord bending, shoulder impurities, and shoulder exposure due to the retraction of the flexible mold. Therefore, how to balance the pressure in the primary shaping stage has always been an irreconcilable contradiction in this field. Summary of the invention

[0021] In order to solve the above problems, the purpose of the present invention is to provide a control method for a tire vulcanization system, which automatically adjusts the molding pressure in the mold cavity according to the change of the mold cavity volume during the mold closing process in the first molding stage to prevent the problem of excessive molding pressure during the mold closing process.

[0022] A tire vulcanization control method is used in a tire vulcanization system. For each side of the flexible mold and the bladder, the vulcanization system includes a shaping nitrogen inlet pipe connected to the bladder steam inlet end and a shaping nitrogen discharge pipeline connected to the bladder discharge end. The method includes:

[0023] One-time shaping:

[0024] Controlling shaping nitrogen to enter the capsule through the shaping nitrogen inlet pipe until a preset first initial shaping pressure is reached;

[0025] Control the clamping of the flexible mold. During the clamping process, the real-time fixed discharge pressure P is determined based on formula 1. 泄 :

[0026]

[0027] Among them, P 泄 is the standard discharge pressure; P0 = initial gauge pressure + back pressure Pb, the initial gauge pressure and back pressure can be directly obtained from the vulcanization system; V01

[0028] is the initial volume of the mold cavity after mold closing; V1 is the volume of the mold cavity at time t; V2 is the volume of the nitrogen exhaust pipeline; A is the area of ​​the throttling orifice plate set in the nitrogen exhaust pipeline; K and the preset adjustment parameters; T = system initial temperature t0 (℃) + 273, where t0 can be directly obtained from the vulcanization system.

[0029] During the mold closing process, the shaping nitrogen is controlled to be discharged from the shaping nitrogen discharge pipeline, and the discharge amount is based on the real-time shaping discharge pressure P 泄 Sure;

[0030] After the first shaping is completed, the second shaping is carried out:

[0031] The shaping nitrogen is controlled to enter the capsule through the shaping nitrogen inlet pipe until a preset second initial shaping pressure is reached, where the second initial shaping pressure is greater than the first initial shaping pressure.

[0032] Preferably, in the primary shaping stage, after the mold is closed to a certain height, a pause is provided; in the secondary shaping stage, no pause is provided after the mold is closed.

[0033] Preferably, the method further comprises: presetting the relationship between the number of times the capsule is used and the first initial directional pressure; counting the cumulative number of times the current capsule is used, and automatically determining the first initial directional pressure based on the cumulative number of times used during a shaping stage.

[0034] Preferably, the relationship between the preset number of capsule uses and the first initial directional pressure includes when the capsule is used 0-50 times, the first initial shaping pressure = 0.06±0.02MPa; when the capsule is used 51-150 times, the first initial shaping pressure = 0.05±0.02MPa; when the capsule is used 151-the upper limit of capsule use, the first initial shaping pressure = 0.04±0.02MPa.

[0035] Preferably, the vulcanization system includes a high-pressure nitrogen recovery pipe and a main discharge pipeline connected to the capsule discharge end. After the vulcanization is completed, part of the high-pressure nitrogen is first recovered through the high-pressure nitrogen recovery pipe until the pressure in the capsule reaches a preset pressure, and then the remaining gas and water are discharged through the main discharge pipeline.

[0036] Preferably, the vulcanization system is used for dual-mode tire vulcanization, including a left bladder, a right bladder and a pipeline system, and the primary shaping and secondary shaping stages of the left bladder and the right bladder are independently controlled.

[0037] Preferably, a connecting pipe is provided between the air inlet ends of the left capsule and the right capsule, and the connecting pipe is respectively connected to a high-temperature steam inlet pipe and a high-pressure nitrogen inlet pipe; the discharge ends of the left capsule and the right capsule are respectively connected to a group of discharge pipes, the two groups of discharge pipes are independent of each other, and each group of discharge pipes includes a main discharge pipe, a high-pressure nitrogen recovery pipe, a steam condensate discharge pipe and a vacuum pipe.

[0038] Preferably, a pressure-maintaining electromagnetic valve is provided on the converging section where all pipelines in each group of discharge pipelines are connected to the capsule.

[0039] Preferably, the aperture of the throttling orifice plate on the steam condensate discharge pipeline is 3-5 mm.

[0040] In the above scheme, a nitrogen discharge pipeline is added to the pipeline system, and part of the nitrogen discharge pipeline can be discharged to adjust the pressure in the mold during the finalization stage, and a discharge solenoid valve is set on the discharge pipeline. The controller in the control system controls the discharge of the nitrogen discharge by controlling the switch of the discharge solenoid valve. In the above method, the real-time discharge pressure P can be automatically determined. 泄 Then the discharge amount of the shaping nitrogen is determined, so that the automatic control of the shaping nitrogen discharge can be realized, and the control is more precise. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 It is a schematic diagram of a pipeline system of a vulcanizing machine in the prior art;

[0042] Figure 2 This is one of the schematic diagrams for analyzing problems in the prior art;

[0043] Figure 3 This is the second schematic diagram of the problem analysis in the prior art;

[0044] Figure 4 This is the third schematic diagram of problem analysis in the prior art;

[0045] Figure 5 The effect comparison chart of setting nitrogen emission for a shaping process;

[0046] Figure 6 This is a comparison chart of the pressure curves for actual use of the vulcanization system, where blue represents the pressure curve without nitrogen discharge, and red represents the pressure curve with nitrogen discharge;

[0047] Figure 7 This is a real-life schematic diagram of nitrogen emission in the workshop;

[0048] Figure 8 This is a comparison chart of the incidence of tire camber, shoulder cord bending, and tire unevenness before and after the finalized emission modification;

[0049] Fig. 9 It is a schematic diagram for explaining the problem of shrinkage of the flexible mold;

[0050] Fig.10 A schematic diagram of the piping system for this application;

[0051] Fig.11 It is a comparison chart of the vulcanization curve with the prior art;

[0052] Fig.12 It is a comparison diagram of the shaping pressure curve with the prior art;

[0053] Fig.13 This is a comparison chart of the pressure at the moment of mold closing during the actual molding process;

[0054] Fig.14 This is a comparison chart of the improvement of the problem of large amount of water accumulation on one side of the tire compared with the existing technology;

[0055] Fig.15 This is a verification diagram of the bubble cutting test for the problem of large amount of water accumulation on one side of the tire;

[0056] Fig.16 This is a comparison test chart of the problem incidence rate based on the F30# model;

[0057] Fig.17 This is a comparison chart of the heating time when the apertures of the throttling orifice plates on the steam condensate discharge pipeline are 3 mm, 4 mm, and 5 mm in diameter in the pipeline system of this embodiment.

[0058] Figure numerals: left capsule 1, right capsule 2, shaping nitrogen inlet pipe 31, connecting pipe 32, high-temperature steam inlet pipe 33, high-pressure nitrogen inlet pipe 34, main exhaust pipe 41, high-pressure nitrogen recovery pipe 42, steam condensate exhaust pipe 43, vacuum pipe 44, shaping nitrogen exhaust pipe 45. DETAILED DESCRIPTION

[0059] The embodiments of the present invention are described in detail below.

[0060] Embodiment 1:

[0061] This embodiment discloses a tire vulcanization control method for a tire vulcanization system, specifically an improvement of the control method of the primary shaping and secondary shaping stages in the tire vulcanization system, especially an improvement of the pressure control in the bladder during the mold closing process in the primary shaping stage.

[0062] Specifically, the method includes:

[0063] One-time shaping:

[0064] Controlling shaping nitrogen to enter the capsule through the shaping nitrogen inlet pipe until a preset first initial shaping pressure is reached;

[0065] Control the clamping of the flexible mold. During the clamping process, the real-time fixed discharge pressure P is determined based on formula 1. 泄 :

[0066]

[0067] Among them, P 泄 is the standard discharge pressure; P0 = initial gauge pressure + back pressure Pb, the initial gauge pressure and back pressure can be directly obtained from the vulcanization system; V01

[0068] is the initial volume of the mold cavity after mold closing; V1 is the volume of the mold cavity at time t; V2 is the volume of the nitrogen exhaust pipeline; A is the area of ​​the throttling orifice plate set in the nitrogen exhaust pipeline; K and the preset adjustment parameters; T = system initial temperature t0 (℃) + 273, where t0 can be directly obtained from the vulcanization system.

[0069] During the mold closing process, the shaping nitrogen is controlled to be discharged from the shaping nitrogen discharge pipeline, and the discharge amount is based on the real-time shaping discharge pressure P 泄 Sure;

[0070] After the first shaping is completed, the second shaping is carried out:

[0071] The shaping nitrogen is controlled to enter the capsule through the shaping nitrogen inlet pipe until a preset second initial shaping pressure is reached, where the second initial shaping pressure is greater than the first initial shaping pressure.

[0072] In the above method, the primary shaping and the secondary shaping are two shaping steps in the shaping stage of the traditional tire vulcanization method. The main difference is that in the prior art, no pressure discharge is set in the shaping stage and the pressure can only be increased by inputting shaping nitrogen. In this embodiment, a shaping nitrogen discharge pipeline is added to the pipeline system, and part of the shaping nitrogen can be discharged through the shaping nitrogen discharge pipeline during the shaping stage to adjust the pressure in the mold, and a shaping discharge solenoid valve is set on the shaping nitrogen discharge pipeline. The controller in the control system controls the discharge of the shaping nitrogen by controlling the switch of the shaping discharge solenoid valve. In the above method, the real-time shaping discharge pressure P can be automatically determined. 泄 Then the discharge amount of the shaping nitrogen is determined, so that the automatic control of the shaping nitrogen discharge can be realized, and the control is more precise.

[0073] For ease of explanation, in this embodiment, the process of controlling the discharge of shaping nitrogen in the primary shaping stage is referred to as shaping discharge. It should be noted that in this embodiment, a capsule and its same-side flexible mold and same-side pipeline are described. For a dual-mode vulcanization system or a multi-mode vulcanization system with more than one capsule, each capsule is controlled by the method of this embodiment. For example, in an embodiment in which the vulcanization system is used for dual-mode tire vulcanization, the vulcanization system includes a left capsule, a right capsule and a pipeline system, and the primary shaping and secondary shaping stages of the left capsule and the right capsule are independently controlled.

[0074] In this embodiment, in order to simplify the calculation process, isothermal calculation is performed. The initial mold cavity nitrogen mass + initial pipeline nitrogen mass equals the mold cavity nitrogen mass at any time + pipeline nitrogen mass + cumulative nitrogen mass discharged from the start to any time, combined with the ideal gas state equation PV = C and Bernoulli equation P1-Pb = 1 / 2*ρ1*c 2, P1 is the initial pressure, Pb is the atmospheric pressure, c is the fluid flow rate and the formula ρ1=K*P1 / T0. The process is calculated isothermally and formula 1 can be obtained.

[0075]

[0076] Among them, P 泄 is the final discharge pressure; P0 = initial gauge pressure + back pressure Pb, the initial gauge pressure and back pressure can be directly obtained from the vulcanization system; V01 is the initial volume of the mold cavity after mold closing; V1 is the volume of the mold cavity at time t; V2 is the volume of the final nitrogen discharge pipeline; A is the area of ​​the throttling orifice plate set in the final nitrogen discharge pipeline; K and the preset adjustment parameters; T = system initial temperature t0 (℃) + 273, where t0 can be directly obtained from the vulcanization system.

[0077] In a specific embodiment, A is the area of ​​the throttling orifice plate provided in the shaped nitrogen discharge pipeline, A=πr 2 =3.14*1.5 2 =7.065(mm 2 ); P0 = initial gauge pressure + 0.1MPa (back pressure) = 0.05 + 0.1 = 0.15Mpa; V01 is the initial volume of the mold cavity = 360L 3 ; V2 is the volume of the nitrogen discharge pipeline (assuming V2 = 1L 3 ); Pb is back pressure = 0.1Mpa; T = system initial temperature t0 (degrees Celsius) + 273 = 20 + 273 = 293. It can be seen that all parameters in formula 1 are directly available, V1 is the data that changes in real time during the mold closing process, which can be directly obtained based on the tire volume feedback from the vulcanizer. By obtaining the mold cavity volume at time t and substituting it into formula 1, the pressure value P that needs to be discharged at time t can be obtained. 泄 .

[0078] Figure 5 It shows the comparison of the pressure inside the capsule with and without the use of shaped discharge under the same conditions. Figure 5 The horizontal axis in the figure represents the change of the volume inside the capsule, the vertical axis represents the change of the fixed pressure inside the capsule, and the three curves respectively represent the curve of the fixed discharge pressure determined with the change of the volume inside the capsule, the curve of the change of the fixed pressure inside the capsule after the fixed discharge control, and the curve of the change of the fixed pressure inside the capsule after the fixed discharge control. By comparison, it can be seen that after the fixed discharge control is performed by the method of this embodiment, when the flexible mold starts to close the mold, the fixed discharge pressure begins to change to reduce the pressure inside the capsule during the closing process to prevent the fixed pressure from being too high, until the closing is completed, the volume inside the capsule is stable, and the fixed pressure and fixed discharge pressure inside the capsule are both stable.

[0079] Figure 6The actual shaping pressure curves in the left and right capsules of the dual-mold vulcanizer are shown in the actual operation of the dual-mold vulcanizer. The left mold adopts the non-shaped discharge control, and the right mold adopts the shaped discharge control. The blue color in the figure represents the left mold, and the red color represents the right mold. By comparison, it can be seen that in the process of synchronously controlling the left and right molds, the shaping pressure changes in the right mold with shaped discharge are relatively stable, and the maximum shaping pressure is relatively significantly smaller than that in the left mold. Figure 7 The actual working diagram of discharging the shaping nitrogen during the primary shaping of the vulcanizing machine is shown.

[0080] And by Figure 8 It can be seen from the schematic comparison results that after the method of this embodiment is used to control the shaping discharge, the incidence of tire arch, shoulder cord bending, and tire unevenness problems is significantly improved. It can be seen that by using the control method of the present application to adjust the shaping pressure in the first shaping stage, the production quality of the tire can be effectively improved.

[0081] After analysis, it was found that the problem of flexible mold retraction was caused by the fact that the shaping force Fsetting in the capsule was greater than or equal to the shaping force Fpower of the flexible mold. Fig. 9 As shown, in a specific embodiment, F is defined as P * π [(D1 / 2) 2 -(d / 2) 2 ]+F piston, where F shaping is the shaping power in the capsule, P shaping is the shaping pressure in the capsule, D1 is the inner diameter of the tire, d is the diameter of the center rod, and F piston is the power of the floating piston. F power = P power * π (D2 / 2) 2 , where Fpower is the power for controlling the clamping of the flexible mold, and D2 is the piston diameter of the power cylinder for controlling the clamping. In the prior art, since the shaping pressure increases significantly during the clamping process, the excessive shaping pressure may lead to Fsetting ≥ Fpower. In the scheme of this embodiment, since a shaping discharge scheme is adopted and pressure is released during the clamping process, it is possible to avoid excessive shaping pressure, keep the shaping pressure within a reasonable range, and effectively avoid the problem of flexible mold shrinkage. Taking model F3# as an example, the Psetting in the first shaping stage is between 0.4-0.8kg / cm. Based on this calculation, Fsetting is always less than Fpower, and there will be no problem of flexible mold shrinkage.

[0082] As a preferred solution, in the first shaping stage, after the mold is closed to a certain height, a pause is made, and this pause time allows the gas between the bladder and the liner to be better discharged; in the second shaping stage, no pause is made after the mold is closed. Take F3# as an example: suppose the internal volume of a 10.00R20 tire is V2=120L, and the variable volume is △V; when the mold is closed, the shaping pressure P1=0.5Kg / cm2 is made when the mold touches the tire blank, and the instantaneous pressure when the mold is closed is P2=0.8Kg / cm2; according to:

[0083] P1V1=P2V2;

[0084] P1(△V+V2)=P2V2;

[0085] 0.5(△V+V2)=0.8V2;

[0086] It is concluded that △V=0.6V2.

[0087] Therefore, the mold closing process is a process of compressing the tire content. There is enough pressure to expel the trapped air between the bladder and the tire embryo, so there is no need to set the secondary molding pause time. Therefore, in order to improve production efficiency while ensuring production quality, compared with the prior art, the pause in the secondary molding stage is cancelled in this application.

[0088] In addition, the method also includes: presetting the relationship between the number of times the capsule is used and the first initial directional pressure; counting the cumulative number of times the current capsule is used, and in a shaping stage, automatically determining the first initial shaping pressure based on the cumulative number of times used. Since too high a pressure of the shaping nitrogen filled in the capsule will accelerate the aging of the capsule, in order to extend the service life of the capsule, the initial shaping nitrogen pressure is determined based on the cumulative number of times the capsule is used in this implementation. Specifically, when the number of times the capsule is used is between 0-50 times, the first initial shaping pressure = 0.06±0.02MPa; when the number of times the capsule is used is between 51-150 times, the first initial shaping pressure = 0.05±0.02MPa; when the number of times the capsule is used is between 151-the upper limit of the capsule use, the first initial shaping pressure = 0.04±0.02MPa.

[0089] The control method of the present application also includes, after the vulcanization is completed, firstly recovering part of the high-pressure nitrogen through the high-pressure nitrogen recovery pipe until the pressure in the capsule reaches a preset pressure, and then discharging the remaining gas and water through the main discharge pipeline. By this arrangement, after the vulcanization is completed, part of the high-pressure nitrogen is recovered and then emptied, nitrogen can be saved and production costs can be reduced.

[0090] Embodiment 2:

[0091] This embodiment provides a tire vulcanization system, including a left bladder 1, a right bladder 2, and a pipeline system. Fig.10 As shown, the steam inlet ends of the left capsule 1 and the right capsule 2 are respectively connected to a shaped nitrogen inlet pipe 31, and a connecting pipe 32 is provided between the air inlet ends of the left capsule 1 and the right capsule 2, and the connecting pipe 32 is respectively connected to a high-temperature steam inlet pipe 33 and a high-pressure nitrogen inlet pipe 34; the discharge ends of the left capsule 1 and the right capsule 2 are respectively connected to a group of discharge pipelines, and the two groups of discharge pipelines are independent of each other, and each group of discharge pipelines includes a main discharge pipeline 41, a high-pressure nitrogen recovery pipe 42, a steam condensation pipe 43 and a vacuum pipe 44.

[0092] This embodiment mainly improves the pipeline system, separates the inlet and outlet pipelines, and separates the outlet pipelines of the left capsule 1 and the right capsule 2. On the one hand, the outlet pipelines of the capsules on both sides are independent, which can avoid problems such as inconsistent pipeline lengths caused by shared pipelines during the condensation discharge stage, ensure the same condensation discharge effect of the capsules on both sides, and solve the problems of temperature difference in the mold and the bottom of the single-sided capsule. In addition, the outlet pipelines on both sides are independent of each other. During the pressure holding stage, even if the pipeline of the capsule on one side leaks, it will not affect the qualified rate of the capsule on the other side.

[0093] In this embodiment, a nitrogen pressure-maintaining valve is provided on the confluence section where all the pipelines in each group of discharge pipelines are connected to the capsule. The nitrogen pressure-maintaining valve is provided at this position to further ensure the pressure-maintaining effect of the capsule discharge pipelines on both sides.

[0094] like Fig.10 As shown, in this embodiment, a high-temperature steam inlet valve is provided on the high-temperature steam inlet pipe 33, a steam condensate discharge valve is provided on the steam condensate discharge pipe 43, a nitrogen inlet valve is provided on the high-pressure nitrogen inlet pipe 34, a nitrogen pressure-maintaining valve is provided on the converging end of the discharge pipe, a medium switching valve is provided on the connecting pipe 32 between the high-temperature steam inlet pipe 33 and the high-pressure nitrogen, and high-temperature steam or high-pressure nitrogen is switched into the capsules on both sides through the medium switching valve, the high-temperature steam inlet valve and the nitrogen inlet valve, a main discharge valve is provided on the main discharge pipe, a vacuum pumping valve is provided on the vacuum pumping pipe 44, a nitrogen recovery valve is provided on the high-pressure nitrogen recovery pipe 42, and a nitrogen shaping balance valve is provided on the shaping nitrogen inlet pipe 31. The controller in the vulcanization system realizes the medium entering and exiting the left and right capsules at each stage by controlling the switching state of the solenoid valves on each pipeline.

[0095] like Figure 10-15 It can be seen that the double-row pipeline of this embodiment has obvious improvements in the following aspects compared with the pipeline system solution in the prior art: Improvement 1. The temperature difference between the left and right molds during the high-pressure steam filling stage is less than 5°C; Improvement 2. The temperature difference between the left and right molds after vulcanization is less than 30°C; Improvement 3. The pressure of the left and right molds is controlled separately during the pressure holding stage (without affecting each other); Improvement 4. The pressure is controlled from the first shaping to the instant of mold closing (0.03~0.10MPa); Improvement 5. There is no water accumulation at the bottom of the bladder (the temperature difference between the upper and lower surfaces of the inner lining layer of the left and right mold tire side parts is small). And by Fig.16 It can be seen that based on the comparative experiment of the vulcanizer model F03#, the use of the pipeline system in this application has significantly reduced the incidence of problems such as low high-pressure steam temperature, inconsistent primary pressure maintenance, uneven tire lining, reduced vulcanization times, and process non-conformity rate.

[0096] The throttle plate aperture used in the single-channel condensate discharge pipe in the prior art is 7mm. In this embodiment, after being divided into a double-channel condensate discharge pipe, the throttle plate aperture on the steam condensate discharge pipe 43 is 4mm. The double-channel condensate discharge hole Φ4 is merged into the single-channel condensate discharge hole diameter calculation:

[0097] πR 2 =2πr 2 , r is the radius of one of the condensation holes in the double-channel condensation tube, r = 2 mm, and R is the radius after merging into the single-channel condensation hole.

[0098] It can be concluded that after being merged into a single path, it is equivalent to a single-path condensation discharge hole with an aperture of Φ5.656, which is smaller than the aperture of the throttle plate in the prior art by 7mm, thereby being able to reduce the loss of high-temperature steam.

[0099] Theoretical calculation of high-temperature steam savings:

[0100] When the single row condensation hole Φ7 is changed to double row condensation hole Φ4, the steam saving is 12.9kg / H·unit - 8.4Kg / H.unit = 4.5Kg / H.unit;

[0101] When changing to double-row condensation holes Φ3, steam can be saved by 12.9kg / H·unit - 4.7Kg / H.unit = 8.2Kg / H.unit.

[0102] According to the above calculation, although it is more energy-efficient to set the throttling orifice plate of the steam condensate discharge pipe 43 to 3 mm in diameter, Fig.17 As shown, for the vulcanizer model F03#, the heating time of the throttling orifice plate with an aperture of 3mm, 4mm, and 5mm on the steam condensate exhaust pipe 43 is about 30 seconds slower than that of the orifice with an aperture of 4mm under the same conditions. Therefore, although the apertures between 3-5 can take into account both energy saving effect and heating time, the aperture of 4mm is the best.

[0103] In the vulcanization system of this embodiment, each set of discharge pipelines further includes a set nitrogen discharge pipe 45, and a set nitrogen discharge valve is provided on the set nitrogen discharge pipe 45. After the set nitrogen discharge valve is provided, the control method shown in Example 1 is used to control the capsules on each side.

[0104] Although the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A tire vulcanization control method, used in a tire vulcanization system, characterized in that: For each side of the flexible mold and the bladder, the vulcanization system includes a shaping nitrogen inlet pipe connected to the bladder steam inlet end and a shaping nitrogen discharge pipeline connected to the bladder discharge end, and the method includes: One-time shaping: Controlling shaping nitrogen to enter the capsule through the shaping nitrogen inlet pipe until a preset first initial shaping pressure is reached; Control the clamping of the flexible mold. During the clamping process, the real-time fixed discharge pressure P is determined based on formula 1. 泄 : Among them, P 泄 is the final discharge pressure; P0 = initial gauge pressure + back pressure Pb, the initial gauge pressure and back pressure can be directly obtained from the vulcanization system; V01 is the initial volume of the mold cavity after mold closing; V1 is the volume of the mold cavity at time t; V2 is the volume of the final nitrogen discharge pipeline; A is the area of ​​the throttling orifice plate set in the final nitrogen discharge pipeline; K and the preset adjustment parameters; T = system initial temperature t0 (℃) + 273, where t0 can be directly obtained from the vulcanization system. During the mold closing process, the shaping nitrogen is controlled to be discharged from the shaping nitrogen discharge pipeline, and the discharge amount is based on the real-time shaping discharge pressure P 泄 Sure; After the first shaping is completed, the second shaping is carried out: The shaping nitrogen is controlled to enter the capsule through the shaping nitrogen inlet pipe until a preset second initial shaping pressure is reached, where the second initial shaping pressure is greater than the first initial shaping pressure.

2. A tire vulcanization control method according to claim 1, characterized in that: In the first shaping stage, after the mold is closed to a certain height, it pauses for a while; in the second shaping stage, there is no pause after the mold starts to be closed.

3. A tire vulcanization control method according to claim 1, characterized in that: The method further includes: presetting the relationship between the number of times the capsule is used and the first initial orientation pressure; counting the cumulative number of times the current capsule is used, and automatically determining the first initial orientation pressure based on the cumulative number of times used in a shaping stage.

4. A tire vulcanization control method according to claim 3, characterized in that: The relationship between the preset number of capsule usage times and the first initial directional pressure includes: when the capsule is used 0-50 times, the first initial shaping pressure = 0.06±0.02MPa; when the capsule is used 51-150 times, the first initial shaping pressure = 0.05±0.02MPa; when the capsule is used 151-the upper limit of capsule usage, the first initial shaping pressure = 0.04±0.02MPa.

5. A tire vulcanization control method according to claim 1, characterized in that: The vulcanization system includes a high-pressure nitrogen recovery pipe and a main discharge pipeline connected to the discharge end of the capsule. After the vulcanization is completed, part of the high-pressure nitrogen is first recovered through the high-pressure nitrogen recovery pipe until the pressure in the capsule reaches a preset pressure, and then the remaining gas and water are discharged through the main discharge pipeline.

6. A tire vulcanization control method according to claim 1, characterized in that: The vulcanization system is used for dual-mode tire vulcanization, and comprises a left bladder, a right bladder and a pipeline system, and the primary shaping and secondary shaping stages of the left bladder and the right bladder are independently controlled.

7. A tire vulcanization control method according to claim 6, characterized in that: A connecting pipe is provided between the air inlet ends of the left capsule and the right capsule, and the connecting pipe is respectively connected to a high-temperature steam inlet pipe and a high-pressure nitrogen inlet pipe; the discharge ends of the left capsule and the right capsule are respectively connected to a group of discharge pipes, and the two groups of discharge pipes are independent of each other. Each group of discharge pipes includes a main discharge pipe, a high-pressure nitrogen recovery pipe, a steam condensate discharge pipe and a vacuum pipe.

8. A tire vulcanization control method according to claim 6, characterized in that: A pressure-maintaining electromagnetic valve is provided on the confluence section where all pipelines in each set of discharge pipelines are connected to the capsule.

9. A tire vulcanization control method according to claim 6, characterized in that: The diameter of the throttling orifice on the steam condensate exhaust pipeline is 3-5mm.

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