A method of tire vulcanization control

Abstract

The application relates to a tire vulcanization control method for a tire vulcanization system, wherein for each side of a flexible mold and a capsule, the vulcanization system comprises a shaping nitrogen inlet pipe connected to a capsule steam inlet end and a shaping nitrogen outlet pipe connected to a capsule discharge end, and the method comprises: primary shaping: controlling the shaping nitrogen to enter the capsule through the shaping nitrogen inlet pipe until a preset first initial shaping pressure is reached; controlling the flexible mold to close, and determining a shaping discharge pressure P in real time during the closing process 泄 ; controlling a part of the shaping nitrogen to be discharged from the shaping nitrogen outlet pipe during the closing process, and the discharge amount is based on the real-time shaping discharge pressure P 泄 . In the primary shaping stage, the shaping pressure in the mold cavity is automatically adjusted according to the change of the mold cavity volume during the closing process, so that the problem of excessively high shaping pressure during the closing process is prevented.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of tire vulcanization technology, and particularly relates to a tire vulcanization system and a control method. BACKGROUND

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

[0003] 1. Shaping: opening a shaping valve, controlling shaping nitrogen gas to be filled into a tire capsule at a process pressure to shape a tire blank;

[0004] 2. High-temperature steam input: opening a high-temperature steam input valve, controlling high-temperature and high-pressure steam to be filled into the tire capsule to make the temperature of the capsule reach a process required temperature;

[0005] 3. High-pressure nitrogen gas input: opening a high-pressure nitrogen gas input valve, controlling high-pressure nitrogen gas to be filled into the tire capsule to make the internal pressure of the capsule reach a process required pressure;

[0006] 4. Nitrogen gas recovery: after vulcanization is completed, opening a nitrogen gas recovery valve to recover nitrogen gas;

[0007] 5. Emptying: opening an emptying valve to empty the remaining gas and condensed water in the system;

[0008] 6. Vacuumizing: opening a vacuumizing valve to vacuumize the inside of the system.

[0009] The pipeline system in the vulcanization machine includes multiple gas input pipelines, exhaust pipelines and multiple electromagnetic valves such as a shaping valve, a high-temperature steam input valve, a high-pressure nitrogen gas input valve, a nitrogen gas recovery valve, an emptying valve and a vacuumizing valve arranged on the pipelines, and the above steps are realized by cooperation of the pipeline system.

[0010] Figure 1The pipe system diagram used in the prior art is used for double mold tire vulcanization, simultaneously controlling left and right active molds and left and right capsules used in cooperation with the left and right active molds. Steam inlet ends of the left and right capsules are respectively connected with one shaping nitrogen inlet pipe (about 0.2 MPa), a first communication pipe is arranged between the steam inlet ends of the left and right capsules, a bottom end of the first communication pipe is respectively connected with one high-temperature steam inlet pipe (about 200℃, 1.7 MPa), one high-pressure nitrogen inlet pipe (about 2.5 MPa), one main exhaust pipe and one vacuumizing pipe; a second communication pipe is arranged between discharge ends of the left and right capsules, a bottom end of the second communication pipe is respectively connected with one nitrogen recovery pipe, one steam condensate exhaust pipe, one shaping exhaust pipe and one vacuumizing pipe. The above pipes are respectively provided with one vacuumizing pipe at inlet and discharge pipe sides, when the vulcanization ends and proceeds to the vacuumizing step, the inlet and discharge pipe sides are simultaneously vacuumized to accelerate the vacuumizing speed. The inlet and discharge pipe sides are respectively provided with one main exhaust pipe to exhaust residual gas at the inlet and discharge pipe sides. The remaining pipes at the inlet and discharge pipe sides are single pipes.

[0011] As shown in Figures 2-4 the above pipe system is used for double mold tire vulcanization, the following problems are found in actual use:

[0012] Problem 1, temperature difference in left and right molds during high-pressure steam filling stage > 5℃;

[0013] Problem 2, temperature difference in left and right molds after vulcanization ends > 30℃;

[0014] Problem 3, left and right mold pressures cannot be controlled independently during pressure maintaining stage (one side pressure maintaining is not good, affecting the other side);

[0015] Problem 4, pressure is too high during the process from one-time shaping to mold closing (0.03-0.20 MPa) and is not controlled;

[0016] Problem 5, water accumulates at the bottom of the single-side inner capsule (the temperature difference between the lowest point of the inner liner in the left and right molds and the surface of the highest point is large, causing a large temperature difference between the inner surfaces of the upper and lower tire sides).

[0017] After analysis, the technicians find that the reasons for the above problems are mainly as follows:

[0018] 1, regarding the problems of mold temperature difference and water accumulation at the bottom of the single-side capsule, the left and right molds are only provided with one steam condensate exhaust pipe, the lengths of the left and right mold condensate exhaust pipes are different, the condensate exhaust effects and time of the two capsules are different, causing the temperature difference (problems 1, 2 and 5).

[0019] 2. Because the communication pipeline is arranged between the discharge ends of the left capsule and the right capsule, if the discharge pipeline of the single-side capsule leaks during the pressure maintaining stage, the other side will also leak, and finally the qualified rate of both sides will be affected due to the insufficient pressure maintaining (problem 3).

[0020] Regarding the above problem 4, the vulcanization system in the prior art usually includes two stages of primary shaping and secondary shaping in the shaping step. When the mold is closed in the primary shaping, the tire inner part is prone to be uneven if the shaping pressure is too low. The problem of the shaping pressure being too low can be solved by increasing the shaping pressure. However, if the shaping pressure is increased, the internal pressure will be instantaneously increased during the mold closing process, which will cause the internal pressure to be too high during the instant of the mold closing process (the instant pressure during the primary shaping to the mold closing process is uncontrolled and the pressure is between 0.03-0.20 MPa), and problems such as the tire inner part arching, the cord bending in the shoulder part, the impurities in the shoulder part, the shoulder part exposed steel wire due to the contraction of the movable mold, and the like are prone to occur. Therefore, how to balance the pressure in the primary shaping stage has always been a pair of contradictory problems in the field. SUMMARY

[0021] In order to solve the above problems, the purpose of the present application is to provide a control method of a tire vulcanization system, in which the shaping pressure in the mold cavity is automatically adjusted according to the volume change of the mold cavity during the mold closing process in the primary shaping stage, so as to prevent the shaping pressure from being too high during the mold closing process.

[0022] A tire vulcanization control method is used in a tire vulcanization system, and for each side movable mold and capsule, the vulcanization system includes a shaping nitrogen inlet pipe connected to the steam inlet end of the capsule and a shaping nitrogen discharge pipeline connected to the discharge end of the capsule. The method comprises the following steps:

[0023] Primary shaping:

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

[0025] Controlling the movable mold to be closed, and during the mold closing process, determining the real-time shaping discharge pressure P based on Formula One 泄 :

[0026]

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

[0028] is the initial volume of the mold cavity after the mold is closed; V1 is the volume of the mold cavity at time t; V2 is the volume of the shaping nitrogen discharge pipeline; A is the area of the throttle orifice plate arranged in the shaping nitrogen discharge pipeline; K is a preset adjustment parameter; and T=t0(℃)+273, wherein t0 can be directly obtained from the vulcanization system.

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

[0030] After the first setting is completed, the second setting is performed:

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

[0032] Preferably, during the first setting stage, the mold is closed to a certain height and then paused for a period of time; during the second setting stage, the mold is started to be closed without an intermediate pause.

[0033] Preferably, the method further comprises a preset relationship between the number of capsule uses and the first initial setting pressure; the cumulative number of uses of the current capsule is counted, and the first initial setting pressure is automatically determined based on the cumulative number of uses during the first setting stage.

[0034] Preferably, the preset relationship between the number of capsule uses and the first initial setting pressure comprises: when the number of capsule uses is between 0 and 50, the first initial setting pressure = 0.06 ± 0.02 MPa; when the number of capsule uses is between 51 and 150, the first initial setting pressure = 0.05 ± 0.02 MPa; and when the number of capsule uses is between 151 and the upper limit of the number of capsule uses, the first initial setting pressure = 0.04 ± 0.02 MPa.

[0035] Preferably, the vulcanization system comprises a high-pressure nitrogen recovery pipe and a main discharge pipeline connected to the discharge end of the capsule, and after vulcanization is completed, a portion of the high-pressure nitrogen is 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 vulcanization of a double-mold tire, and comprises a left capsule, a right capsule, and a pipeline system, and the first setting and the second setting stages of the left capsule and the right capsule are independently controlled.

[0037] Preferably, a communication pipeline is provided between the inlet ends of the left capsule and the right capsule, and the communication pipeline is connected to one high-temperature steam inlet pipe and one high-pressure nitrogen inlet pipe; the discharge ends of the left capsule and the right capsule are respectively connected to a set of discharge pipelines, and the two sets of discharge pipelines are independent of each other, and each set of discharge pipelines comprises a main discharge pipeline, a high-pressure nitrogen recovery pipe, a steam condensate discharge pipe, and a vacuum pumping pipe.

[0038] Preferably, a pressure maintaining electromagnetic valve is provided in each set of discharge pipelines.

[0039] Preferably, the orifice plate on the steam exhaust pipeline has an orifice diameter of 3-5 mm.

[0040] In the above scheme, the shaping nitrogen exhaust pipeline is added to the pipeline system, part of the shaping nitrogen is exhausted through the shaping nitrogen exhaust pipeline to adjust the in-mold pressure during the shaping stage, the shaping exhaust solenoid valve is arranged on the shaping nitrogen exhaust pipeline, and the controller in the control system controls the opening and closing of the shaping exhaust solenoid valve to control the exhaust of the shaping nitrogen. In the above method, the real-time shaping exhaust pressure P 泄 The exhaust amount of the shaping nitrogen is further determined, so that the automatic control of the shaping nitrogen exhaust can be realized, and the control is more accurate. BRIEF DESCRIPTION OF DRAWINGS

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

[0042] Figure 2 A schematic diagram of problem analysis in the prior art is shown;

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

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

[0045] Figure 5 A comparison diagram of the effect of setting the shaping nitrogen exhaust for the first shaping process is shown;

[0046] Figure 6 A comparison diagram of the shaping pressure curve presented by the actual use of the vulcanizing system is shown, in which blue represents the pressure curve without shaping nitrogen exhaust, and red represents the pressure curve with shaping nitrogen exhaust;

[0047] Figure 7 A schematic diagram of the shaping nitrogen exhaust in the workshop is shown;

[0048] Figure 8 A comparison diagram of the occurrence rate of the tire arch, shoulder cord bending, and uneven tire problems before and after the shaping exhaust modification is shown;

[0049] Figure 9 A schematic diagram for explaining the problem of the live die retraction is shown;

[0050] Figure 10 A schematic diagram of the pipeline system of the present application is shown;

[0051] Figure 11 A comparison diagram of the vulcanizing curve with the prior art is shown;

[0052] Figure 12 A comparison diagram of the shaping pressure curve with the prior art is shown;

[0053] Figure 13 Pressure comparison chart for the moment of mold closing in the actual shaping process;

[0054] Figure 14 Comparison chart for improvement of the problem of a large amount of water accumulation on one side of the tire side compared with the prior art;

[0055] Figure 15 Verification chart for the bubble cutting test for the problem of a large amount of water accumulation on one side of the tire side;

[0056] Figure 16 Test chart for the problem occurrence rate based on F30# model;

[0057] Figure 17 Comparison chart for the temperature rise time of the orifice plate aperture of 3mm, 4mm and 5mm in the steam condensate discharge pipeline in the pipeline system of the embodiment.

[0058] The figure mark: left capsule 1, right capsule 2, shaping nitrogen inlet pipe 31, communication pipeline 32, high temperature steam inlet pipe 33, high pressure nitrogen inlet pipe 34, main discharge pipeline 41, high pressure nitrogen recovery pipe 42, steam condensate discharge pipe 43, vacuum pipe 44, shaping nitrogen discharge pipe 45. DETAILED DESCRIPTION

[0059] The embodiments of the application will be described in detail below.

[0060] Embodiment 1:

[0061] The embodiment discloses a tire vulcanization control method, which is used for a tire vulcanization system, in particular, an improvement of the control method of the primary shaping and the secondary shaping stages in the tire vulcanization system, and especially an improvement of the pressure control in the capsule during the mold closing process of the primary shaping stage.

[0062] Specifically, the method comprises:

[0063] Primary shaping:

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

[0065] Control the mold closing, and during the mold closing process, determine the real-time shaping discharge pressure P 泄 :

[0066]

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

[0068] V0 is the initial volume of the mold cavity after the mold is closed; V1 is the volume of the mold cavity at time t; V2 is the volume of the shaping nitrogen discharge pipeline; A is the area of the throttle orifice plate provided in the shaping nitrogen discharge pipeline; K is a preset adjustment parameter; T = system initial temperature t0 (°C) + 273, wherein t0 can be directly obtained from the vulcanization system.

[0069] During the mold closing process, a portion of 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 determined;

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

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

[0072] In the above method, the first shaping and the second shaping are two shaping steps in the shaping stage of the traditional tire vulcanization method, and the main difference lies in that in the prior art, the discharge pressure is not set in the shaping stage and can only be increased by inputting the shaping nitrogen. In the present embodiment, the shaping nitrogen discharge pipeline is additionally provided in the pipeline system, which can discharge a portion of the shaping nitrogen in the shaping stage to adjust the pressure in the mold, and a shaping discharge solenoid valve is provided on the shaping nitrogen discharge pipeline. The controller in the control system controls the discharge of the shaping nitrogen by controlling the opening and closing of the shaping discharge solenoid valve. In the above method, the real-time shaping discharge pressure P 泄 is automatically determined, and the discharge amount of the shaping nitrogen is further determined, so that automatic control of the shaping nitrogen discharge can be realized, and the control is more accurate.

[0073] For the sake of convenience, the process of discharging the shaping nitrogen in the first shaping stage in the present embodiment is referred to as shaping discharge. It should be noted that the present embodiment is described for one bladder and its same-side movable mold and same-side pipeline, and for a vulcanization system with more than one bladder, such as a double-mold vulcanization system or a multi-mold vulcanization system, the method of the present embodiment is used for control for each bladder. For example, in an embodiment in which the vulcanization system is used for double-mold tire vulcanization, the vulcanization system includes a left bladder, a right bladder, and a pipeline system, and the first shaping and the second shaping stages of the left bladder and the right bladder are independently controlled.

[0074] In the present embodiment, isothermal calculation is used for simplicity. The initial nitrogen mass in the mold cavity + the initial nitrogen mass in the pipeline is equal to the nitrogen mass in the mold cavity at any time + the nitrogen mass in the pipeline + the cumulative discharged nitrogen mass from the start to the arbitrary time, combined with the ideal gas state equation PV = C and the Bernoulli equation P1-Pb = 1 / 2 * p1 * 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 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 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 standard nitrogen discharge pipeline; A is the area of ​​the throttling orifice set in the standard nitrogen discharge pipeline; K is the preset adjustment parameter; 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 gas 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 obtainable. V1 is the data that changes in real time during the mold closing process and 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 required to be discharged at time t can be obtained. 泄 .

[0078] Figure 5 The figure 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 represents the change in capsule volume, and the vertical axis represents the change in the set pressure within the capsule. The three curves represent the set pressure determined by the change in capsule volume, the change in the set pressure within the capsule after using set pressure control, and the change in the set pressure within the capsule after using set pressure control. A comparison shows that after using the set pressure control method of this embodiment, the set pressure begins to change at the beginning of mold closing to reduce the pressure within the capsule during the closing process and prevent excessive pressure. The pressure remains stable until the capsule volume stabilizes after closing, and both the set pressure and the set pressure remain stable.

[0079] Figure 6For the actual work of the dual-mode curing machine, the actual profiling pressure curve in the left and right capsules of the left mold adopts amorphous discharge control, and the right mold adopts definite profiling discharge control. Blue in the figure represents the left mold, and red represents the right mold. Comparison shows that in the process of synchronously controlling the left mold and the right mold to close, the profiling pressure in the right mold with definite profiling discharge changes relatively stably, and the maximum profiling pressure is relatively obviously smaller than that in the left mold. Figure 7 An actual working diagram of discharging profiling nitrogen in the profiling of the curing machine is shown.

[0080] And by Figure 8 As shown in the comparison result, after the profiling discharge is controlled by the method of the embodiment, the occurrence rate of the tire inner arch, the shoulder cord bending, and the tire inner unevenness is obviously improved. It can be seen that by adjusting the profiling pressure in the profiling stage by using the control method of the application, the production quality of the tire can be effectively improved.

[0081] Through analysis, it is concluded that the problem of the loose mold retracting is caused by the profiling power Fprofiling in the capsule being greater than or equal to the power Fpower of the loose mold closing. As shown in the formula: Figure 9 In specific embodiments, Fprofiling=Pprofiling*π[(D1 / 2) 2 -(d / 2) 2 ]+Fpiston, wherein Fprofiling is the profiling power in the capsule, Pprofiling is the profiling pressure in the capsule, D1 is the inner diameter of the tire, d is the diameter of the center rod, and Fpiston is the power of the floating piston. Fpower=Ppower*π(D2 / 2) 2 , wherein Fpower is the power of controlling the loose mold closing, and D2 is the piston diameter of the power cylinder for controlling the loose mold closing. In the prior art, since the profiling pressure is greatly increased during the closing process, the case of Fprofiling≥Fpower caused by excessive profiling pressure may occur. In the scheme of the embodiment, since the profiling discharge scheme is adopted, the pressure is released during the closing process, which can avoid excessive profiling pressure, keep the profiling pressure in a reasonable range, and effectively avoid the problem of the loose mold retracting. Taking the F3# as an example, Pprofiling in the profiling stage is between 0.4-0.8 kg / cm, and Fprofiling calculated based on this is always less than Fpower, so the problem of the loose mold retracting does not occur.

[0082] As a preferred scheme, in the profiling stage, the closing is paused for a period of time after reaching a certain height, and the pause time allows the gas between the capsule and the inner liner to be better discharged; in the secondary profiling stage, the closing is started without pausing in the middle. Taking F3# as an example: assuming that the volume of the 10.00R20 tire is V2=120L, the change volume is ΔV; the mold touches the tire profiling pressure P1=0.5Kg / cm when closing, and the pressure P2=0.8Kg / cm at the moment of closing; 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 volume of the tire contents. There is sufficient pressure to expel the air trapped between the bladder and the tire blank, so there is no need to set a pause time for the secondary shaping. Therefore, in order to improve production efficiency while ensuring production quality, compared with the existing technology, the pause in the secondary shaping stage is cancelled in this application.

[0088] Furthermore, the method further includes presetting the relationship between the number of times the capsule is used and the first initial shaping pressure; counting the cumulative number of times the current capsule is used, and automatically determining the first initial shaping pressure based on the cumulative number of times used during a shaping phase. Since excessively high pressure of the shaping nitrogen gas filled into the capsule will accelerate capsule aging, in order to extend the service life of the capsule, in this embodiment, the initial shaping nitrogen pressure is determined based on the cumulative number of times the capsule is used. Specifically, if the number of times the capsule is used is between 0 and 50, the first initial shaping pressure = 0.06 ± 0.02 MPa; if the number of times the capsule is used is between 51 and 150, the first initial shaping pressure = 0.05 ± 0.02 MPa; if the number of times the capsule is used is between 151 and the upper limit of the capsule use, the first initial shaping pressure = 0.04 ± 0.02 MPa.

[0089] The control method of the present application further includes, after vulcanization is completed, first recovering a portion 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 pipe. This arrangement, which recovers a portion of the high-pressure nitrogen after vulcanization and then discharges it, can save nitrogen and reduce production costs.

[0090] Example 2:

[0091] This embodiment provides a tire vulcanization system, including a left bladder 1, a right bladder 2, and a pipeline system. Figure 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 pipes, and the two groups of discharge pipes are independent of each other. Each group of discharge pipes includes a main discharge pipe 41, a high-pressure nitrogen recovery pipe 42, a steam condensate discharge pipe 43 and a vacuum pipe 44.

[0092] This embodiment primarily improves the piping system, separating the inlet and outlet pipes, and also separating the outlet pipes for left capsule 1 and right capsule 2. The independent outlet pipes for both capsules avoid issues like inconsistent pipe lengths caused by shared pipes during the condensation removal phase, ensuring consistent condensation removal for both capsules, and addressing issues like temperature differences within the mold and the issue of a unilateral capsule bottom. Furthermore, the independent outlet pipes mean that even if a leak develops in the pipe on one capsule during the pressure-holding phase, it will not affect the pass rate of the other capsule.

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

[0094] like Figure 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, and a nitrogen pressure-maintaining valve is provided at 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. The medium switching valve, the high-temperature steam inlet valve, and the nitrogen inlet valve switch the flow of high-temperature steam or high-pressure nitrogen into the capsules on both sides. A main discharge valve is provided on the main discharge pipe, a vacuum valve is provided on the vacuum pipe 44, a nitrogen recovery valve is provided on the high-pressure nitrogen recovery pipe 42, and a nitrogen balancing valve is provided on the sizing nitrogen inlet pipe 31. The controller in the vulcanization system controls the on / off states of the solenoid valves in each pipe to control the flow of medium into and out of the left and right capsules at each stage.

[0095] like Figures 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 charging 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 one-time shaping to the moment 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 side parts is small). And by Figure 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 tires, reduced vulcanization times, and process non-conformity rates.

[0096] In the prior art, the orifice diameter of the throttle plate used in a single-pass condensate drain pipe is 7mm. In this embodiment, after the condensate drain pipe is divided into two-pass condensate drain pipes, the orifice diameter of the throttle plate on the steam condensate drain pipe 43 is 4mm. The dual-pass condensate drain hole Φ4 is combined into the single-pass condensate drain hole diameter calculation:

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

[0098] It can be concluded that after being merged into a single channel, the single channel condensate discharge hole is equivalent to a hole diameter of Φ5.656, which is smaller than the hole diameter of the throttle plate in the prior art by 7mm, thereby reducing 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 saving is 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 diameter of the steam condensate discharge pipe 43 to 3mm, Figure 17 As shown in the figure, for the curing machine model F03#, the temperature rise 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 temperature rise time, the aperture of 4mm is the best.

[0103] In this embodiment, each set of discharge pipes in the vulcanization system further includes a nitrogen discharge pipe 45 for setting nitrogen, which is provided with a nitrogen discharge valve for setting nitrogen. After the nitrogen discharge valve is provided, the control method described in Example 1 is used to control the bladders on each side.

[0104] While 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 invention, and that the scope of the invention is defined by the claims and their equivalents.

Claims

1. A tire vulcanization control method for a tire vulcanization system, characterized in that: For each side of the flexible mold and bladder, the vulcanization system includes a shaping nitrogen inlet pipe connected to the bladder steam inlet end and a shaping nitrogen discharge pipe connected to the bladder discharge end. The method includes: One-time shaping: Controlling the 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 : ——Formula 1, Among them, P 泄 is the final discharge pressure; P0 = initial gauge pressure + back pressure Pb, where the initial gauge pressure and back pressure can be obtained directly 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 set in the final nitrogen discharge pipeline; K is the preset adjustment parameter; T / Kelvin = system initial temperature t0 / °C + 273, where t0 can be obtained directly from the vulcanization system; During the mold closing process, the shaping nitrogen is controlled to be discharged from the shaping nitrogen discharge pipeline. 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 a relationship between the number of times the capsule is used and the first initial shaping pressure; counting the cumulative number of times the current capsule is used, and automatically determining the first initial shaping pressure based on the cumulative number of times used during a shaping phase.

4. A tire vulcanization control method according to claim 3, characterized in that: The relationship between the preset number of times the capsule is used and the first initial shaping pressure includes the following: when the number of times the capsule is used is between 0 and 50 times, the first initial shaping pressure = 0.06 0.02MPa; The number of times the capsule is used is between 51-150 times, and the first initial shaping pressure = 0.05 0.02MPa; The number of times the capsule is used is between 151 times and the upper limit of the capsule use, and the first initial setting 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 connected to the capsule discharge end and a main discharge pipeline. After 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-mold tire vulcanization, and includes a left bladder, a right bladder, and a pipeline system. 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, which are 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 the 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 aperture of the throttling orifice on the steam condensate exhaust pipe is 3-5mm.

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