Automatic temperature and pressure adjusting device for heating fluid in parallel heating system

Abstract

The invention relates to the field of tire vulcanization technology and equipment in tire production and manufacturing, in particular to an automatic heating fluid temperature and pressure adjusting device in a parallel heating system, which is mounted on a tail steam pipeline of a vulcanization external temperature steam parallel heating system. According to the device, the outflow flow resistance of vulcanization tail gas is adjusted in real time, the steam inlet amount of the two heating devices in the parallel heating system is forced to be adjusted, and therefore the purpose that the temperature of the two heating devices in parallel is controlled in a following mode is achieved; the steam pressure and temperature in the left heating cavity and the right heating cavity are kept stable when the steam circulates or is discharged, the left heating device and the right heating device are heated in the same way, and loss of discharged heating steam can be reduced.

Description

Technical Field

[0001] The invention relates to the field of tire vulcanization technology and vulcanization equipment in tire production and manufacturing, and in particular to a heating fluid temperature and pressure automatic regulating device in a parallel heating system. Technical Background

[0002] Vulcanization is one of the most critical process steps in tire production. It is a process in which the embryo undergoes chemical and physical reactions under the action of heat and pressure and is finally shaped into a finished tire. It is also one of the processes that most affects the quality of the finished tire.

[0003] The external temperature of vulcanization refers to the heating temperature of the outer side of the tire embryo. It is usually heated by steam heating the upper hot plate, lower hot plate, mold sleeve and other heating devices and then heating the tire embryo by heat conduction. The upper hot plate, lower hot plate, mold sleeve and other heating devices used for vulcanization external temperature heating are collectively referred to as heating devices. The parallel heating system refers to the use of a set of steam inlet valves to provide heat sources for two heating devices at the same time through parallel pipelines, and run a set of PID algorithm controlled heating systems. The external temperature heating of the vulcanization of the dual-mode vulcanizer often adopts a parallel heating system, such as parallel steam heating of the left and right hot plates in the dual-mode vulcanizer, and parallel steam heating of the left and right steamers.

[0004] A dual-mode vulcanizer refers to a vulcanization machine that can install two sets of molds at the same time and can process and produce two tires at the same time. The same process standards and the same process steps are applied to the two tire blanks in production. At the same time, it is hoped that the two molds have the same or similar vulcanization temperature and pressure curves to ensure stable product quality.

[0005] The control method of the parallel heating system is to perform PID calculation using the temperature setting value and the actual temperature value of the heating device, and use the calculation result to control the opening degree of the heating device's steam inlet film regulating valve in real time, and control the amount of steam entering by controlling the opening degree of the valve to achieve the purpose of controlling the external temperature. The process is to heat the steam inlet when the actual temperature is lower than the set value, and stop the steam inlet when the actual temperature is equal to or higher than the set value, waiting for the steam consumption and reducing the temperature through the steam trap.

[0006] Problems:

[0007] When heating, the temperature changes of the left and right heating devices in parallel are different, and the difference is large:

[0008] There are large differences in the actual processing tolerances and symmetry of the pipeline assembly of the two heating devices in the parallel heating system. These differences will affect the steam consumption and steam inlet flow distribution of the two heating devices in the parallel heating system. In addition, due to the large size of the vulcanizer, the environmental positions and external insulation states of the upper and lower hot plates, mold sleeves and other heating devices are different, which makes the external heat dissipation of the heating devices different, resulting in different steam consumption of the two heating devices in the parallel heating system. However, the vulcanization tail steam and condensed water of the two heating devices in the parallel heating system are discharged independently through the steam trap. The above reasons will cause different steam densities in the heating chambers of the two heating devices in parallel. Steam with high density has high pressure and high temperature, while steam with low density has low pressure and low temperature. However, the PID control algorithm of the parallel heating system is based on the temperature feedback value of one of the vulcanization heating devices and the set value to calculate and control the opening of the steam inlet valve. The temperature on the other side will deviate more and more from the control target over time, and the follow-up will become very poor, resulting in different temperatures of the left and right heating devices in the parallel system, which has a very large impact on the quality of the tire.

[0009] High steam consumption:

[0010] Because the left and right heating devices of the parallel heating system each use an independent steam trap to discharge sulfurized tail steam and condensed water, if the feedback value of the PID control is on the side with more steam consumption or less steam inlet distribution of the heating device, that is, the side with lower measured temperature, then the steam density and steam pressure in the heating device on the other side will be high, and its temperature may even exceed the highest value of the process standard, then the amount of steam escaping from the steam trap on this side will increase, resulting in more steam consumption. Summary of the invention

[0011] In order to effectively solve the above problems, the present invention designs a novel automatic adjustment device. The principle is to judge the steam density in the two heating chambers by comparing the pressure of the sulfurized exhaust steam of the left and right heating devices in the parallel system. The side of the heating device with a smaller sulfurized exhaust steam pressure indicates that the steam density is low, and the heating device on this side needs more steam to enter for heating. Conversely, the side of the heating device with a larger sulfurized exhaust steam pressure indicates that the steam content is large. The device of the present invention changes the outflow resistance of the sulfurized exhaust steam, forcing the heating steam to flow more from the parallel steam inlet to the heating chamber of the heating device on the side with low steam pressure when the sulfurization heating temperature rises. By comparing the sulfurized exhaust steam pressure of the parallel heating devices, the outflow resistance of the sulfurized heating steam is adjusted, so that the heating device on the side with more steam consumption or less steam inlet can allocate more steam for heating, thereby achieving the purpose of synchronous temperature following of the two heating devices in the parallel heating system.

[0012] The technical solution adopted by the present invention to solve the technical problem is as follows: the device of the present invention is composed of a main pressure comparator and an accessory buffer box. The pressure comparator is designed with two left and right chambers, which are separated by a diaphragm in the middle. A movable connecting rod and an actuator are installed on the diaphragm. The actuators are respectively provided with plugs. Conical or arc-shaped small-mouth channels for the outflow of fluid media are respectively designed at the bottom of the two chambers of the pressure comparator. Pressure interfaces connected to the sulfurized tail steam of two heating devices of the parallel heating system are respectively designed on both sides of the two chambers. A circulating steam outlet, a condensed water discharge outlet and a mounting seat and an interface for the pressure comparator are designed on the cache box. If the heating system adopts a steam circulation heating method, the circulating steam outlet is connected to the circulation pipeline of the heating system, and the condensed water discharge outlet is connected to a cut-off valve. The cut-off valve is opened to discharge condensed water according to the liquid level control of the cache box. If the heating system adopts a conventional heating method, the steam circulation outlet is sealed, and the condensed water discharge outlet is directly connected to a drain valve or a timed drain cut-off valve for discharge. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 : Schematic diagram of the device of the present invention

[0014] Figure 2 : Schematic diagram of the vulcanization external temperature parallel heating system

[0015] Figure 3 : Side view of the present invention

[0016] Figure 4 : Planing view of the present invention

[0017] Figure 5 : Partial sliced ​​view of the present invention

[0018] Figure 6 : Figure 5 A partial enlarged view of

[0019] Figure 7 : Schematic diagram of state change of the present invention

[0020] Figure 1 Middle: M1. Pressure comparator, M2. Buffer box.

[0021] Figure 2 Middle: The thick black line indicates the flow trajectory of the heating steam, A. External temperature heating steam inlet control valve, B. Left mold heating cavity, C. Right mold heating cavity, D. The device of the present invention, E. Left mold temperature sensor, F. Right mold temperature sensor, G. Condensate discharge control valve, H. Steam inlet heating pipeline, L. Steam circulation pipeline.

[0022] Figure 3 Middle: 1.I Condensate upper level sensor, 2. Steam circulation outlet, 3. Condensate discharge interface, 4. Condensate lower level sensor.

[0023] Figure 4 Middle: 5. Liquid level float.

[0024] Figure 5 Middle: 6. Left actuator, 7. Left pressure interface, 8. Moving rod, 9. Left housing of pressure comparator, 10. Right housing of pressure comparator, 11. Diaphragm, 12. Right pressure interface, 13. Right actuator.

[0025] Figure 6 Middle: 14. Small flow channel on the left, 15. Plug on the left, 16. Plug on the right, 17. Small flow channel on the right.

[0026] Figure 7 Middle: P_L. Steam pressure at the left interface, P_R. Steam pressure at the right interface. DETAILED DESCRIPTION

[0027] The invention is made by Figure 1 The pressure comparator M1 shown in the figure is the main part, and the buffer box M2 is an accessory. It is installed in the vulcanization external temperature parallel control system Figure 2 The position of D in the middle.

[0028] The pressure comparator M1 is shown in the cut diagram Figure 5 As shown, a left pressure interface 7 is provided on the left shell 9 for connecting to the exhaust steam pipeline of the left heating device of the parallel heating system, a left small flow channel 14 for fluid outflow is provided at the bottom of the left shell 9, and the opening is conical or arc-shaped, similar to the shape of the left plug 15, a right pressure interface 12 is provided on the right shell 10 for connecting to the exhaust steam pipeline of the right heating device of the parallel heating system, a right small flow channel 17 for fluid outflow is provided at the bottom of the right shell 10, and the opening is conical or arc-shaped, similar to the shape of the right plug 16, a connecting rod 8 is located at the center of the diaphragm and is fixed to the diaphragm 11 by a clamping device, the connecting rod 8 is used to limit the moving direction of the diaphragm 11 and the actuator, the left actuator 6 and the right actuator 13 are both fixed on the connecting rod and are located on both sides of the diaphragm 11, a left plug 15 is provided on the left actuator 6, corresponding to the opening of the left small flow channel 14, a right plug 16 is provided on the right actuator 13, corresponding to the right small flow channel 17, and the bottoms of the left shell 9 and the right shell 10 are both provided with guide grooves for the movement of the left and right actuators.

[0029] The buffer tank M2 is designed to temporarily store the condensed water from the heating steam and to act as a buffer when the steam is circulating or the shut-off valve is discharged. Figure 3 And planed surface Figure 4As shown in the schematic diagram, the cache box is provided with a steam circulation outlet 2 and a condensate discharge interface 3. A mounting seat and an interface for installing a pressure comparator are provided on the cache box. A liquid level float 5, an upper liquid level sensor 1 and a lower liquid level sensor 4 are provided in the cache box to complete the discharge control of condensate. The cache box can also use other condensate level detection devices to control the discharge of condensate. The pressure comparator M1 is fixedly installed on the cache box M2 using a sealing gasket and screws.

[0030] The device of the present invention is used in the whole external temperature parallel heating system Figure 2 The operation in is described as follows:

[0031] When the left mold temperature sensor E or the right mold temperature sensor F participating in the PID control operation detects that the temperature of the sulfurized tail steam in the pipeline is lower than the process standard value, the external temperature heating steam inlet control valve A opens to allow high-temperature steam to enter the heating steam inlet pipeline H and be diverted to the left mold heating cavity B and the right mold heating cavity C. The pressure of the steam in the left and right heating cavities is simultaneously transmitted to the two sides of the diaphragm of the device through the left and right pressure interfaces of the device D of the present invention, and a pressure difference is formed on both sides of the diaphragm. Under the action of the pressure difference, the diaphragm pushes the connecting rod and the actuator to move. At the same time, the plug on the actuator moves away from or close to the corresponding small flow channel opening, which changes the outflow resistance of the sulfurized tail steam in the left and right heating cavities, and quickly amplifies the steam pressure difference in the two heating devices of the parallel system at the steam inlet, forcing the heating steam to be diverted more to the mold cavity on the side with smaller steam pressure, so that the heating mold cavity on this side obtains more heating steam until the steam pressure in the heating cavities on both sides is balanced or the steam inlet heating process is completed, and the condensed water precipitated from the steam enters the buffer box through the small flow channel and is discharged according to the liquid level control.

[0032] The specific operating state of the present invention is described in detail as follows:

[0033] When the steam pressure in the left mold heating cavity B and the right mold heating cavity C is equal, it means that the heating steam temperature of the left and right heating devices is the same. Figure 7 As shown in the P_L=P_R diagram, the diaphragm is in the middle position at this time, and the left and right small channels from the pressure comparator M1 to the buffer box M2 are both unobstructed. At this time, the device of the present invention only plays a blocking role, so that the steam pressure in the left and right heating chambers is relatively stable when the steam circulates or is discharged at a fixed time in the heating system, avoiding large fluctuations.

[0034] When the steam pressure of the left mold heating cavity B is less than the pressure of the right mold heating cavity C, Figure 7As shown in the P_L<P_R diagram, at this time, the diaphragm drives the connecting rod and the actuator to move to the left under the action of the pressure difference, the right plug reduces or blocks the outflow small channel on the right, and the left plug moves away from the left small channel, so that the steam in the heating steam inlet pipeline H is more diverted to the left mold heating chamber B, so that the left mold heating chamber B is quickly heated until the steam pressure of the left mold heating chamber B is the same as that of the right mold heating chamber C or the heating is completed. After the heating is completed, the steam in the left and right heating chambers will flow again through the steam inlet passage of the parallel pipeline for pressure balance. If it is detected that the control temperature is less than the set value at this time, the heating system will heat again until the steam temperature in the left and right heating chambers is the same, the diaphragm returns to the middle position, and the left and right plugs also return to the natural initial position.

[0035] When the steam pressure of the left mold heating cavity B is greater than the pressure of the right mold heating cavity C, Figure 7 As shown in the P_L>P_R diagram, at this time, the diaphragm drives the connecting rod and the actuator to move to the right under the action of the pressure difference, the left plug reduces or blocks the outflow small channel on the left, and the right plug moves away from the right small channel, so that the steam in the heating steam inlet pipeline H is diverted more to the right mold heating chamber C, so that the right mold heating chamber C is quickly heated until the steam pressure of the right mold heating chamber C is the same as that of the left mold heating chamber B or the heating is completed. After the heating is completed, the steam in the left and right heating chambers will flow again through the steam inlet passage of the parallel pipeline for pressure balance. If it is detected that the control temperature is less than the set value at this time, the heating system will be heated again by steam until the steam temperature in the left and right heating chambers is the same, the diaphragm returns to the middle position, and the left and right plugs also return to the natural initial position.

Claims

1. A device for automatically adjusting the temperature and pressure of a heating fluid in a parallel heating system, comprising a pressure comparator and a buffer box, characterized in that: The pressure comparator is the main content of the present invention, which is composed of a diaphragm, a moving rod, left and right actuators, left and right outflow small channels and left and right shells. The left and right shells clamp the diaphragm to form two left and right chambers. The left and right shells are provided with pressure interfaces. The left and right actuators are located on both sides of the diaphragm and are fixed on the moving rod. The moving rod limits the movement direction of the diaphragm and the actuator. The left and right actuators are provided with plugs. The left and right outflow small channels are respectively arranged at the bottom of the left and right shells. By comparing the pressure of the heating fluid on both sides of the diaphragm, the pressure difference pushes the moving rod and the actuator to move, so that the plug on the actuator is away from or close to the corresponding small channel opening, thereby changing the resistance of the heating fluid to flow out of the corresponding small channel.

2. The cache box according to claim 1, characterized in that: The cache box is used as an accessory of the present invention. The box body is provided with a heating fluid circulation interface and a heating fluid discharge interface. A mounting seat and an interface for installing a pressure comparator are provided on the box body. The comparator is sealed and fixed to the cache box by a sealing gasket and screws.

3. The automatic temperature and pressure regulating device for heating fluid in a parallel heating system according to claim 1, characterized in that: The small outflow channel in the comparator connects the comparator and the cache box, and has a conical or arc-shaped opening on one side of the comparator. The opening direction includes but is not limited to opposite openings, including opposite openings. When the openings are opposite, the actuator and the plug are installed in opposite directions, and the comparator performs a reverse function.

4. The automatic temperature and pressure regulating device for heating fluid in a parallel heating system according to claim 1, characterized in that: Each component of the pressure comparator is not limited to a specific shape or size, and includes various forms of deformation and changes in processing size.

5. The automatic temperature and pressure regulating device for heating fluid in a parallel heating system according to claim 1, characterized in that: Including but not limited to the parallel heating of external temperature steam for vulcanization, including the parallel heating and pressurization of internal pressure hot water for vulcanization and other parallel use of multiple fluids.

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