Rapid preheating control device of thin-plate cut-tobacco drier

Abstract

The utility model discloses a rapid preheating control device for a thin-plate cut-tobacco dryer. The rapid preheating control device comprises a steam pressure reducing valve, a first-area steam pipeline, a second-area steam pipeline, a first-area thin plate and a second-area thin plate, one end of the steam pressure reducing valve is provided with a steam inlet, and the other end is respectively connected with the first-area steam pipeline and the second-area steam pipeline; the other ends of the first-area steam pipeline and the second-area steam pipeline are connected with a steam distributor through rotary joints; the first-area thin plate and the second-area thin plate are located in a roller of the cut tobacco dryer, the roller is connected with the steam distributor, so that steam of the first-area steam pipeline is conveyed to the first-area thin plate to be pressurized, and steam of the second-area steam pipeline is conveyed to the second-area thin plate to be pressurized; condensed water pressurized by the first-area thin plate and the second-area thin plate is conveyed into the water storage tank through a first-area condensed water pipeline and a second-area condensed water pipeline respectively. According to the utility model, the sheet cut-tobacco drier can be quickly preheated under the original preheating condition, and meanwhile, the impact of a condensed water hammer on a sheet in the sheet cut-tobacco drier can be avoided.

Description

Technical Field

[0001] The utility model relates to the field of cigarette processing equipment, and more specifically to a quick preheating control device for a thin-plate tobacco drying machine. Background Art

[0002] There are many thin plate wire drying machines used in the tobacco industry's silk production lines, such as the SH6 thin plate wire drying machine and the KLD-2Z thin plate wire drying machine. These thin plate wire drying machines must be pressurized and preheated before production. The purpose is to prevent the water hammer generated by condensed water from impacting the thin plate wire drying machine through the pressurized preheating process before production, thereby affecting the service life of the thin plate wire drying machine; secondly, through pressurized preheating, the wire drying machine reaches the standby state, that is, the wire drying machine is close to the production condition so that it can quickly enter the production state; thirdly, prevent condensed water in the thin plate wire drying machine, which in turn affects the moisture control of the material head and prevents the material head from producing spotted smoke.

[0003] Taking the KLD-2Z thin-plate tofu drying machine as an example, its preheating requires three conditions: a pressurization time of at least 900 seconds, a pressure in zones 1 and 2 of at least 0.4 bar, and a condensate temperature of at least 108°C. These three conditions dictate that the steam and condensate lines with thin plates be slowly opened by applying pressure through the steam regulating valves in zones 1 and 2, at a maximum opening of 13%. Condensate in the condensate line is primarily discharged into the condensate tank via a float trap. This trap operates intermittently, filtering condensate and blocking steam. The trap's drainage effect is better when both water and steam coexist, while it is less effective when the system is entirely condensate. Therefore, the initial preheating phase, primarily the pressurization phase, is dominated by excess condensate in the line, causing the trap to malfunction. This is particularly true in winter, when condensate in the steam line is higher, and the pressurization and opening process takes too long. Sometimes, even after preheating for over an hour, preheating conditions may not be met. Long preheating time not only affects production progress, but also causes the equipment of the entire production line to run idle for a long time, thereby increasing energy consumption and production costs, while also increasing the maintenance intensity of maintenance personnel.

[0004] Therefore, it is necessary to design a simple, reliable and feasible control device, which can quickly preheat the thin plate wire drying machine under the original preheating conditions regardless of the season and whether the working steam is saturated, while not causing condensation water hammer to impact the thin plates in the thin plate wire drying machine. Utility Model Content

[0005] One purpose of the present invention is to provide a new technical solution for a fast preheating control device for a thin-plate tofu drying machine, so as to solve the problems raised in the above-mentioned background technology.

[0006] According to a first aspect of the present invention, a rapid preheating control device for a thin plate tofu drying machine is provided, comprising a steam pressure reducing valve, a steam pipeline in a first zone, a steam pipeline in a second zone, a thin plate in a first zone, and a thin plate in a second zone;

[0007] One end of the steam pressure reducing valve is provided with a steam inlet, and the other end is connected to the steam pipeline of the first zone and the steam pipeline of the second zone respectively;

[0008] The other ends of the steam pipeline of the first zone and the steam pipeline of the second zone are connected to a steam distributor through a rotary joint; the thin plates of the first zone and the thin plates of the second zone are located in a drum of the tofu drying machine, and the drum is connected to the steam distributor to transport the steam of the steam pipeline of the first zone to the thin plates of the first zone for pressurization, and transport the steam of the steam pipeline of the second zone to the thin plates of the second zone for pressurization;

[0009] The condensed water generated by the pressurization and heat exchange of the thin plates in the first zone and the thin plates in the second zone is transported to the water storage tank through the condensed water pipeline in the first zone and the condensed water pipeline in the second zone respectively.

[0010] Optionally, according to the rapid preheating control device for the thin-plate tofu drying machine of the utility model, a steam regulating valve and a pressure transmitter are sequentially provided on the steam pipeline of the first zone to adjust and detect the steam pressure passing through the steam pipeline of the first zone;

[0011] The second zone steam pipeline is provided with a second zone steam regulating valve and a second zone pressure transmitter in sequence to adjust and detect the steam pressure passing through the second zone steam pipeline.

[0012] Optionally, according to the rapid preheating control device of the thin plate wire drying machine described in the utility model, a zone temperature sensor, a zone filter and a zone drain valve are provided in sequence on the zone condensate pipeline. The zone temperature sensor is used to detect the condensate temperature in the zone condensate pipeline in real time, and the zone drain valve is used to accelerate the discharge of the condensate into the water storage tank.

[0013] Optionally, according to the rapid preheating control device of the thin plate wire drying machine described in the utility model, an observation window is also provided between the zone filter and the zone drain valve, so as to detect the flow condition of the zone condensate pipeline and the working condition of the zone filter through the observation window.

[0014] Optionally, according to the rapid preheating control device for the thin-plate tofu drying machine of the present invention, a condensate discharge pipeline for a zone is further connected in parallel to the zone condensate pipeline, one end of the zone condensate discharge pipeline is connected between the zone temperature sensor and the zone filter, and the other end is connected between the zone trap and the water storage tank;

[0015] A manual stop valve and a pneumatic angle seat valve are sequentially provided on the condensate discharge pipeline of the first zone to control the opening and closing of the condensate pipeline of the first zone.

[0016] Optionally, according to the rapid preheating control device of the thin plate wire drying machine described in the utility model, a tuning fork liquid level switch is also provided on the front end of the zone condensate discharge pipeline of the zone condensate at the temperature sensor of the zone 1 to detect the liquid level of the condensate in the zone condensate discharge pipeline of the zone 1.

[0017] Optionally, according to the rapid preheating control device of the thin plate wire drying machine described in the utility model, the two-zone condensate pipeline is provided with a two-zone temperature sensor, a two-zone filter and a two-zone steam trap in sequence, the two-zone temperature sensor is used to detect the condensate temperature in the two-zone condensate pipeline in real time, and the two-zone steam trap is used to accelerate the discharge of condensate into the water storage tank.

[0018] Optionally, according to the rapid preheating control device for the thin plate wire drying machine described in the utility model, a second zone observation window is also provided between the second zone filter and the second zone drain valve, so as to detect the flow condition of the second zone condensate pipeline and the working condition of the second zone filter through the second zone observation window.

[0019] Optionally, according to the fast preheating control device for the thin-plate tofu drying machine of the utility model, a second-zone condensate water discharge pipeline is further connected in parallel to the second-zone condensate water pipeline, two ends of the second-zone condensate water discharge pipeline are connected between the second-zone temperature sensor and the second-zone filter, and the other two ends are connected between the second-zone steam trap and the water storage tank;

[0020] The second zone condensate discharge pipeline is provided with a second zone manual stop valve and a second zone pneumatic angle seat valve in sequence to control the opening and closing of the second zone condensate pipeline.

[0021] Optionally, according to the rapid preheating control device of the thin plate wire drying machine described in the utility model, a second-zone tuning fork liquid level switch is also provided on the second-zone condensate discharge pipeline at the front end of the second-zone temperature sensor to detect the liquid level of the condensate in the second-zone condensate discharge pipeline.

[0022] This utility model rapidly preheats the sheet tofu dryer while maintaining preheating conditions while preventing condensate water hammer from impacting the sheets within the dryer. The device boasts a simple design and reliable operation, effectively maintaining the ideal preheating time and conditions under varying steam quality conditions in different seasons. This ensures smooth production flow and reduces idle time for other equipment, thereby reducing energy consumption and production costs while also alleviating maintenance workload. It is widely applicable to reducing preheating time during pressurized preheating of sheet tofu dryers used in the tobacco industry.

[0023] Other features and advantages of the present invention will become apparent from the following detailed description of exemplary embodiments of the present invention with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.

[0025] Figure 1 This is a schematic structural diagram of the rapid preheating control device for the thin-plate tofu drying machine disclosed in the utility model;

[0026] Figure 2 This is a schematic diagram of condensed water discharge of the rapid preheating control device for the thin-plate tofu drying machine disclosed in the utility model;

[0027] Figure 3 This is a schematic diagram of the control principle of the rapid preheating control device for the thin plate tofu drying machine disclosed in the utility model.

[0028] Description of reference numerals:

[0029] 1- Zone 1 steam pipeline; 2- Zone 1 pressure transmitter; 3- Zone 2 pressure transmitter; 4- Zone 2 steam pipeline; 5- Zone 1 temperature sensor; 6- Zone 1 condensate pipeline; 7- Zone 2 condensate pipeline; 8- Zone 2 temperature sensor; 9- Steam distributor; 10- Rotary joint; 11- Zone 2 thin plate; 12- Zone 1 thin plate; 13- Roller; 14- Zone 2 filter; 15- Zone 2 observation window; 16- Zone 2 steam trap; 17- Zone 1 filter; 18- Water storage tank; 19- Zone 1 observation window; 20- Zone 1 steam trap; 21- Zone 2 steam regulating valve; 22- Steam-water separator; 23- Steam pressure reducing valve; 24- Zone 1 steam regulating valve;

[0030] 25-Zone 2 tuning fork liquid level switch; 26-Zone 2 manual stop valve; 27-Zone 2 pneumatic angle seat valve; 28-Zone 1 tuning fork liquid level switch; 29-Zone 1 pneumatic angle seat valve; 30-Zone 1 manual stop valve. DETAILED DESCRIPTION

[0031] Various exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It should be noted that unless otherwise specifically stated, the relative arrangements of components and steps, numerical expressions and numerical values ​​set forth in these embodiments do not limit the scope of the present invention.

[0032] The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the present invention, its application, or uses.

[0033] Technologies, methods, and equipment known to ordinary technicians in the relevant art may not be discussed in detail, but where appropriate, the technologies, methods, and equipment should be considered part of the specification.

[0034] In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not limiting. Therefore, other examples of the exemplary embodiments may have different values.

[0035] according to Figures 1 to 3 As shown, the utility model provides a fast preheating control device for a thin plate tofu drying machine, comprising a steam pressure reducing valve 23, a steam pipeline 1 in a first zone, a steam pipeline 4 in a second zone, a thin plate 12 in a first zone, and a thin plate 11 in a second zone;

[0036] One end of the steam pressure reducing valve 23 is provided with a steam inlet, and the other end is connected to the steam pipeline 1 of zone 1 and the steam pipeline 4 of zone 2 respectively;

[0037] The other ends of the steam pipe 1 of zone 1 and the steam pipe 4 of zone 2 are connected to a steam distributor 9 via a rotary joint 10; the thin plates 12 of zone 1 and the thin plates 11 of zone 2 are located in a drum 13 of the tofu drying machine, and the drum 13 is connected to the steam distributor 9 to transport the steam from the steam pipe of zone 1 to the thin plates 12 of zone 1 for pressurization, and the steam from the steam pipe of zone 2 to the thin plates 11 of zone 2 for pressurization;

[0038] The condensed water generated by the pressurization and heat exchange of the first zone thin plate 12 and the second zone thin plate 11 is transported to the water storage tank 18 through the first zone condensed water pipeline 6 and the second zone condensed water pipeline 7 respectively.

[0039] Furthermore, a zone 1 steam regulating valve 24 and a zone 1 pressure transmitter 2 are sequentially provided on the zone 1 steam pipeline 1 to regulate and detect the steam pressure passing through the zone 1 steam pipeline 1;

[0040] The zone 2 steam pipeline 4 is provided with a zone 2 steam regulating valve 21 and a zone 2 pressure transmitter 3 in sequence to regulate and detect the steam pressure passing through the zone 2 steam pipeline 4 .

[0041] Furthermore, a zone temperature sensor 5, a zone filter 17 and a zone steam trap 20 are sequentially provided on the zone condensate pipe 6. The zone temperature sensor 5 is used to detect the condensate temperature in the zone condensate pipe 6 in real time, and the zone steam trap 20 is used to accelerate the discharge of the condensate into the water storage tank 18.

[0042] A zone condensate pipe 6 is provided with a zone temperature sensor 5, a zone filter 17 and a zone steam trap 20 in sequence. The zone temperature sensor 5 is used to detect the condensate temperature in the zone condensate pipe 6 in real time, and the zone steam trap 20 is used to accelerate the discharge of the condensate into the water storage tank 18.

[0043] The purpose of preheating the thin plate wire drying machine is to prevent the water hammer generated by condensed water from impacting the thin plates of the thin plate wire drying machine through the preheating and pressurization process before production, thereby affecting the service life of the thin plates of the thin plate wire drying machine; secondly, through pressurized preheating, the wire drying machine reaches the standby state, that is, the wire drying machine is close to the production conditions to facilitate rapid entry into the production state; thirdly, prevent condensed water in the thin plate wire drying machine, thereby affecting the moisture control of the material head, and at the same time prevent the material head from producing spotted smoke. Therefore, the first step is the pressurization preheating process: in the automatic state, the preheating button is activated, and the steam is divided into two paths after passing through the steam pressure reducing valve 23 and the steam-water separator 22. The first path of steam is controlled by the program to make the steam regulating valve 24 of the first zone open in a step-by-step manner (the opening does not exceed 13%), and its steam pressure is detected by the pressure transmitter 2 of the first zone. The steam enters the rotary joint 10 through the steam pipeline 1 of the first zone, and then enters the thin plate 12 of the first zone through the steam distributor 9 for pressurization. The condensed water generated by the pressurization and heat exchange of the thin plate 12 of the first zone returns to the steam distributor 9 through the thin plate 12 of the first zone. The condensed water then enters the condensed water pipeline 6 of the first zone through the rotary joint 10, and its condensed water temperature is detected by the temperature sensor 5 of the first zone installed on the condensed water pipeline 6 of the first zone. The condensed water then passes through the filter 17 of the first zone and the steam trap 20 of the first zone to be discharged into the water storage tank 18.

[0044] Similarly, the second steam path is controlled by the program to open the second zone steam regulating valve 21, and its steam pressure is detected by the second zone pressure transmitter 3. The steam enters the rotary joint 10 through the second zone steam pipeline 4, and then enters the second zone thin plate 11 through the steam distributor 9 for pressurization and heat exchange. The generated condensed water returns to the steam distributor 9 through the second zone thin plate 11, and then enters the second zone condensate pipeline 7 through the rotary joint 10. The condensed water temperature is detected by the second zone temperature sensor 8, and the condensed water is discharged into the water storage tank 18 through the second zone filter 14 and the second zone steam trap 16.

[0045] The total time of this pressurization process cannot be less than 900 seconds; when the pressure transmitter 2 of zone 1 detects that the pressure is not less than 0.4 bar, and the temperature sensor 5 of zone 1 detects that the condensate temperature is not less than 108°C, the pressurization process of zone 1 is completed; similarly, when the pressure transmitter 3 of zone 2 detects that the pressure is not less than 0.4 bar, and the temperature sensor 8 of zone 2 detects that the condensate temperature is not less than 108°C, the pressurization process of zone 2 is completed; when the pressurization processes of these two zones are completed, preheating will begin. At this time, the opening of the steam regulating valve 24 of zone 1 and the steam regulating valve 21 of zone 2 will gradually increase through PID control. The steam pressure detected by the pressure transmitter 2 of zone 1 and the pressure detected by the pressure transmitter 3 of zone 2 are converted into the cylinder wall temperature of zone 1 and the cylinder wall temperature of zone 2 through the program. When the cylinder wall temperature of zone 1 and the cylinder wall temperature of zone 2 reach the set value, the preheating is completed and the system is switched to standby state.

[0046] Furthermore, a first-zone observation window 19 is provided between the first-zone filter 17 and the first-zone steam trap 20 to monitor the flow of the first-zone condensate pipe 6 and the operating condition of the first-zone filter 17. A second-zone observation window 15 is provided between the second-zone filter 14 and the second-zone steam trap 16 to monitor the flow of the second-zone condensate pipe 7 and the operating condition of the second-zone filter 14.

[0047] Furthermore, a zone 1 condensate discharge pipeline is connected in parallel to the zone 1 condensate pipeline 6. One end of the zone 1 condensate discharge pipeline is connected between the zone 1 temperature sensor 5 and the zone 1 filter 17, and the other end is connected between the zone 1 steam trap 20 and the water storage tank 18. A zone 1 manual stop valve 30 and a zone 1 pneumatic angle seat valve 29 are sequentially provided on the zone 1 condensate discharge pipeline to control the opening and closing of the zone 1 condensate pipeline 6.

[0048] A second zone condensate discharge pipeline is also connected in parallel to the second zone condensate pipeline 7. One end of the second zone condensate discharge pipeline is connected between the second zone temperature sensor 8 and the second zone filter 14, and the other end is connected between the second zone steam trap 16 and the water storage tank 18; the second zone condensate discharge pipeline is provided with a second zone manual stop valve 26 and a second zone pneumatic angle seat valve 27 in sequence to control the opening and closing of the second zone condensate pipeline 7.

[0049] In this embodiment, the utility model is provided with a condensed water discharge pipe device of a fast preheating control device for a thin-plate tofu drying machine. Figure 2 First, select two sets of manual stop valves with flanges, as the manual stop valve 30 for zone 1 and the manual stop valve 26 for zone 2. Then, select two sets of angle seat valves with flanges, as the pneumatic angle seat valve 29 for zone 1 and the pneumatic angle seat valve 27 for zone 2. The flanges of the two pneumatic angle seat valves must be the same size as the flanges of the two manual stop valves. Then, select one or two sets of single connecting flanges, the dimensions of which must be the same as the flanges of the angle seat valves and the manual stop valves.

[0050] like Figure 2As shown, first, connect and fix the above-mentioned manual stop valve 30 and the pneumatic angle seat valve 29 in the first zone through their flanges with screws, nuts and gaskets; then open an open interface at a suitable position before the filter 17 in the first zone, and open an open interface at a suitable position after the steam trap 20 in the first zone; then select two stainless steel pipes with the same diameter and thickness as the condensate pipe, measure, bend and deform them, and cut them into appropriate lengths according to the connection dimensions of the manual stop valve 30 and the pneumatic angle seat valve 29 in the first zone and the dimensions of the two sets of single connection flanges; then, according to the actual situation, connect the prepared stainless steel pipes to the first zone. One end is welded to an open interface of the condensate pipe, and the other end is welded to a single connecting flange port; one end of the other stainless steel pipe is welded to another open interface of the condensate pipe, and the other end is welded to another single connecting flange port (pay attention to the connection angle and direction of the connecting flange with the flange of the manual shut-off valve 30 in zone 1 and the flange of the pneumatic angle seat valve 29 in zone 1 when welding); finally, the flange of the manual shut-off valve 30 in zone 1 and the flange of the pneumatic angle seat valve 29 in zone 1 are connected and fixed to the welded single connecting flange respectively with screws, nuts and gaskets.

[0051] It should be noted that the purpose of opening interfaces at two places in the above-mentioned zone 1 condensate pipe 6 is to connect the zone 1 manual stop valve 30 and the zone 1 pneumatic angle seat valve 29 in the zone 1 condensate discharge pipe in parallel with the zone 1 filter 17 and the zone 1 steam trap 20 in the zone 1 condensate discharge pipe; since the condensate pipe is basically full of condensate during the pressurization process, the float-type steam trap works intermittently, filters the condensate, blocks the steam, and when water and steam coexist, the steam-draining effect is better under the action of steam. If it is all condensate, the steam-draining effect is worse; after the parallel connection, the zone 1 pneumatic angle seat valve 29 is opened through program control during the pressurization stage so that the condensate in the condensate pipe passes through the zone 1 manual stop valve 30 and the zone 1 pneumatic angle seat valve 29 in the zone 1 condensate discharge pipe directly to the water storage tank 18, which can quickly discharge the condensate in the condensate pipe and quickly meet the preheating conditions. In addition, the purpose of installing a manual stop valve 30 in the condensate discharge pipeline of Zone 1 is that once the pneumatic angle seat valve 29 of Zone 1 is damaged and the direct flow cannot be controlled, the condensate discharge pipeline of Zone 1 must be shut off by the manual stop valve 30. Otherwise, after the condensate in the condensate pipeline is discharged, the entire Zone 1 pipeline (Zone 1 condensate pipeline 6 and Zone 1 steam pipeline 1) will be directly connected to the water storage tank 18. When the opening of the Zone 1 steam regulating valve 24 is only 13% during the pressurization stage, the steam pressure of the Zone 1 steam pipeline 1 will be very low. In this way, it is difficult for the pressure transmitter 2 of Zone 1 to detect that the pressure reaches 0.4 bar, and the preheating condition of Zone 1 is difficult to achieve. Therefore, the manual stop valve 30 of Zone 1 must be used to prevent accidents.

[0052] For example Figure 2As shown, first connect and fix the above-mentioned two-zone manual stop valve 26 and two-zone pneumatic angle seat valve 27 through their flanges with screws, nuts and gaskets; then open an open interface at a suitable position in front of the two-zone filter 14, and open an open interface at a suitable position after the two-zone cold drain valve; then select two stainless steel pipes with the same diameter and thickness as the condensate pipeline, measure, bend and deform them, and cut them into appropriate lengths according to the connection dimensions of the two-zone manual stop valve 26 and the two-zone pneumatic angle seat valve 27 and the dimensions of the two sets of single connecting flanges; next, according to actual conditions, weld one end of the manufactured stainless steel pipe to a condensate pipeline open interface, and weld the other end to a single connecting flange port; weld one end of the manufactured other stainless steel pipe to another condensate pipeline open interface, and weld the other end to another single connecting flange port (pay attention to the connection angle and direction of the connecting flange with the flange of the two-zone manual stop valve 26 and the flange of the two-zone pneumatic angle seat valve 27 when welding); finally, connect and fix the flange of the two-zone manual stop valve 26 and the two-zone pneumatic angle seat valve 27 The flanges are connected to the welded single connection flanges by using appropriate screws, nuts and gaskets to fix them. The technical principle is the same as that of the condensate discharge pipeline in zone 1.

[0053] Furthermore, a first-zone tuning fork level switch 28 is provided on the first-zone condensate discharge pipeline, located in front of the first-zone temperature sensor 5, to detect the level of condensate in the first-zone condensate discharge pipeline. A second-zone tuning fork level switch 25 is provided on the second-zone condensate discharge pipeline, located in front of the second-zone temperature sensor 8, to detect the level of condensate in the second-zone condensate discharge pipeline.

[0054] In this embodiment, if Figure 2 Two tuning fork level switches are shown within the two dashed boxes. A tuning fork level switch, namely, Zone 1 tuning fork level switch 28 and Zone 2 tuning fork level switch 25 (e.g., model WYC01ST from Jiangsu Tianwei Company), is installed slightly above the vertical section of the Zone 1 condensate pipe 6 and Zone 2 condensate pipe 7. The purpose of installing the tuning fork level switches is to address the uncertainties in winter weather, as the steam source moisture content varies. This makes it difficult to determine the condensate discharge from the condensate pipe during pressurization, and therefore the amount of condensate remaining in the pipe is uncertain. Therefore, tuning fork level switches are installed for monitoring. This installation and location also allows for accurate determination of whether the condensate pipe is full of condensate. The tuning fork level switches are installed slightly above the vertical section of the Zone 1 condensate pipe 6 and Zone 2 condensate pipe 7. The purpose of detecting the absence of condensate at this location is to confirm that the condensate discharge from the pipe is nearing completion.

[0055] Based on Figure 3 As shown in FIG. 1 , the control program of the pneumatic angle seat valve of the rapid preheating control device of the thin plate tofu drying machine of the utility model is designed as follows.

[0056] Step 1: Create a DB block in the Siemens PLC control program and define the complex time data type within the data block. Call system functions SFC0 and SFC1 to write and read the system time. The program determines that when reading March to October each year (defined as the months with less condensate in the steam during this period), M1500.0 is set to 1. The program determines that when reading January to February and November to December each year (defined as the months with more condensate in the steam during this period), M1500.0 is set to 0.

[0057] Step 2: After the preheat start button is activated during the pressurization stage, the automatic status bit + preheat start flag bit + M1500.0 normally closed point + M1510.0 normally open point (the input signal of the tuning fork liquid level switch 28 in zone 1) are connected in series. Then the automatic status bit + preheat start flag bit + M1500.0 normally open point + timer T10 normally open point (this timer is an SE timer, which is triggered after the M1500.0 normally open point signal is connected in series with the preheat start signal and is defined as 20 minutes) series signal is connected in parallel with the automatic status bit + preheat start flag bit + M1500.0 normally closed point + M1510.0 normally open point branch and output Q17.0. Q17.0 controls the action of the solenoid valve and controls the compressed air through the solenoid valve to open the pneumatic angle seat valve 29 in the zone 1 condensate discharge pipeline, allowing the condensate in the condensate pipeline to be quickly discharged into the water storage tank 18. Procedure 2 Description: In months with low steam moisture content (March-October), time control is used. After preheating starts, the condensate drain line is opened to quickly drain condensate. After 20 minutes of draining (this time was determined after multiple experiments and trade-offs), the condensate drain line is closed to quickly achieve preheating conditions. In months with high steam moisture content (January-February, November-December), a zone 1 tuning fork level switch 28 is used for control. After preheating starts, the zone 1 condensate drain line is opened to quickly drain condensate. When the zone 1 tuning fork level switch 28 detects no condensate, i.e., at the end of condensate discharge, the condensate drain line is closed to quickly achieve preheating conditions.

[0058] Step 3: After the preheat start button is activated during the pressurization phase, the automatic status bit + preheat start flag + M1500.0 normally closed point + M1510.1 normally open point (the input signal of the tuning fork level switch 25 in zone 2) are connected in series. Then, the series signal of the automatic status bit + preheat start flag + M1500.0 normally open point + timer T10 normally open point (this timer is the same as in step 2) is connected in parallel with the automatic status bit + preheat start flag + M1500.0 normally closed point + M1510.1 normally open point branch, and then output to Q17.1. Q17.1 controls the operation of the solenoid valve, which controls compressed air to open the zone 2 pneumatic angle seat valve 27 in the zone 2 condensate discharge line, allowing the condensate in the condensate line to be quickly discharged into the water storage tank 18. The procedure description is the same as above.

[0059] Through the design, installation, and programming of the aforementioned device, this control device can rapidly preheat the sheet tofu dryer while maintaining the original preheating conditions, while preventing condensate water hammer from impacting the sheet within the dryer. This device, with its simple design and reliable operation, effectively maintains the ideal preheating time and conditions under varying steam quality conditions in different seasons, ensuring smooth production flow and reducing idle time for other equipment, thereby reducing energy consumption and production costs while also alleviating maintenance workload. It is particularly suitable for rapidly preheating the KLD-2Z sheet tofu dryer used in tobacco industry silk production lines during pressurized preheating. It is also widely used to reduce preheating time during pressurized preheating of sheet tofu dryers used in the tobacco industry.

[0060] Although some specific embodiments of the present invention have been described in detail through examples, those skilled in the art will appreciate that the above examples are for illustration only and are not intended to limit the scope of the present invention. Those skilled in the art will appreciate that modifications may be made to the above embodiments without departing from the scope and spirit of the present invention. The scope of the present invention is defined by the appended claims.

Claims

1. A fast preheating control device for a thin-plate tofu drying machine, characterized in that: Including steam pressure reducing valve, steam pipeline in zone 1, steam pipeline in zone 2, thin plate in zone 1 and thin plate in zone 2; One end of the steam pressure reducing valve is provided with a steam inlet, and the other end is connected to the steam pipeline of the first zone and the steam pipeline of the second zone respectively; The other ends of the steam pipeline of the first zone and the steam pipeline of the second zone are connected to a steam distributor through a rotary joint; the thin plates of the first zone and the thin plates of the second zone are located in a drum of the tofu drying machine, and the drum is connected to the steam distributor to transport the steam of the steam pipeline of the first zone to the thin plates of the first zone for pressurization, and transport the steam of the steam pipeline of the second zone to the thin plates of the second zone for pressurization; The condensed water generated by the pressurization and heat exchange of the thin plates in the first zone and the thin plates in the second zone is transported to the water storage tank through the condensed water pipeline in the first zone and the condensed water pipeline in the second zone respectively.

2. The rapid preheating control device for the thin-plate tofu drying machine according to claim 1, characterized in that: The steam pipeline of zone one is provided with a steam regulating valve of zone one and a pressure transmitter of zone one in sequence to adjust and detect the steam pressure passing through the steam pipeline of zone one; The second zone steam pipeline is provided with a second zone steam regulating valve and a second zone pressure transmitter in sequence to adjust and detect the steam pressure passing through the second zone steam pipeline.

3. The rapid preheating control device for the thin-plate tofu drying machine according to claim 1, characterized in that: The zone condensate pipeline is provided with a zone temperature sensor, a zone filter and a zone steam trap in sequence. The zone temperature sensor is used to detect the condensate temperature in the zone condensate pipeline in real time, and the zone steam trap is used to accelerate the discharge of condensate into the water storage tank.

4. The rapid preheating control device for the thin-plate tofu drying machine according to claim 3, characterized in that: An observation window is further provided between the zone one filter and the zone one steam trap, so as to detect the flow condition of the zone one condensate pipeline and the working condition of the zone one filter through the observation window.

5. The rapid preheating control device for the thin-plate tofu drying machine according to claim 4, characterized in that: A condensate discharge pipe for a zone is also connected in parallel to the zone 1 condensate pipe, one end of the condensate discharge pipe for a zone is connected between the zone 1 temperature sensor and the zone 1 filter, and the other end is connected between the zone 1 steam trap and the water storage tank; A manual stop valve and a pneumatic angle seat valve are sequentially provided on the condensate discharge pipeline of the first zone to control the opening and closing of the condensate pipeline of the first zone.

6. The rapid preheating control device for the thin-plate tofu drying machine according to claim 5, characterized in that: A tuning fork level switch is also provided on the zone condensate discharge pipeline at the front end of the zone 1 temperature sensor to detect the level of the condensate in the zone 1 condensate discharge pipeline.

7. The rapid preheating control device for the thin-plate tofu drying machine according to claim 1, characterized in that: The second zone condensate pipeline is provided with a second zone temperature sensor, a second zone filter and a second zone steam trap in sequence. The second zone temperature sensor is used to detect the condensate temperature in the second zone condensate pipeline in real time, and the second zone steam trap is used to accelerate the discharge of condensate into the water storage tank.

8. The rapid preheating control device for the thin-plate tofu drying machine according to claim 7, characterized in that: A second zone observation window is further provided between the second zone filter and the second zone steam trap, so as to detect the flow condition of the second zone condensate pipeline and the working condition of the second zone filter through the second zone observation window.

9. The rapid preheating control device for the thin-plate tofu drying machine according to claim 8, characterized in that: The second zone condensate pipe is also connected in parallel with a second zone condensate discharge pipe, two ends of the second zone condensate discharge pipe are connected between the second zone temperature sensor and the second zone filter, and the other two ends are connected between the second zone steam trap and the water storage tank; The second zone condensate discharge pipeline is provided with a second zone manual stop valve and a second zone pneumatic angle seat valve in sequence to control the opening and closing of the second zone condensate pipeline.

10. The rapid preheating control device for the thin-plate tofu drying machine according to claim 9, characterized in that: A second-zone tuning fork liquid level switch is also provided on the second-zone condensate discharge pipeline at the front end of the second-zone temperature sensor to detect the liquid level of the condensate in the second-zone condensate discharge pipeline.

Images