Centralized oil supply temperature control system for plastic pipe production workshop

Abstract

The invention belongs to the technical field of temperature control of plastic processing equipment, and discloses a centralized oil supply temperature control system for a plastic pipe production workshop. According to the method, the initial heating temperature is calculated by constructing the pipeline size-temperature loss mapping relation and combining the required temperature of each branch, so that the oil temperature loss deviation caused by pipeline difference is reduced, the adjusting pressure of secondary temperature control is reduced, and the adaptability of the initial heating temperature is improved. The oil temperature of the input end is monitored and corrected in real time through the secondary temperature control module, it is ensured that the actual working temperature of each device is consistent with the required temperature, and the stability of the plastic pipe product quality is directly improved. Through target temperature optimization and targeted regulation and control, circulation efficiency reduction or equipment damage caused by too large temperature difference of the backflow oil liquid is avoided, the service life of the system is prolonged, and the controllability of the collection temperature of the backflow oil liquid is improved. The temperature of the main pipeline is dynamically adjusted through the centralized heating correction module according to actual temperature control data, invalid temperature control operation is reduced, and energy consumption is reduced.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of plastic processing equipment temperature control, and relates to a centralized oil supply temperature control system for a plastic pipe production workshop. BACKGROUND

[0002] In the production process of plastic pipes, core equipment such as extruders and molding dies need to be provided with stable heat sources by heat conducting oil, and the precise control of the working temperature of the equipment directly affects the physical properties and appearance quality of the products. In order to improve the energy utilization efficiency, a centralized oil supply system is used in modern workshops, that is, heat conducting oil is heated and distributed to each device through a main pipeline, and then flows back to the collection point through a branch pipeline for recycling.

[0003] However, the temperature control precision of the centralized oil supply system has always been a problem in the industry. Due to the differences in the sizes of the branch pipelines, the temperature loss of the heat conducting oil during transmission is inconsistent. At the same time, the required temperatures of the devices may be different, and the traditional system cannot balance the centralized heating of the main pipeline and the precise temperature control of the branch, resulting in large deviations of the actual input oil temperature of the devices, and the temperature of the collected backflow oil fluctuates violently, which not only affects the product quality, but also causes energy waste due to repeated temperature control adjustment.

[0004] Specifically, the traditional technical solution still has the following problems: 1. The initial heating temperature setting of the traditional technical solution is unreasonable, and the influence of the size difference of the branch pipelines on the temperature loss is not considered. The initial heating temperature of the main pipeline is set only according to experience or the demand of a single device, resulting in that the oil temperature of some branches reaching the devices is too high or too low, and frequent secondary adjustment is required.

[0005] 2. The traditional technical solution lacks real-time monitoring and dynamic adjustment of the oil temperature at the input end of the device, and only relies on the direct distribution of the heating temperature of the main pipeline, which cannot match the real-time required temperature of each device, resulting in fluctuations in the working temperature of the device.

[0006] 3. The collected temperature of the backflow oil of the traditional technical solution is unstable, and the output oil temperature of each branch is different. When collected, the temperature fluctuation easily affects the circulation efficiency of the heat conducting oil, and even causes pipe scaling and device damage due to local high temperature or low temperature.

[0007] 4. The traditional technical solution lacks a dynamic correction mechanism, and the heating temperature of the main pipeline is not adjusted based on the actual temperature control data feedback, resulting in that the secondary temperature control device is in a high load operation state for a long time, the energy consumption is high, and the temperature control precision is difficult to guarantee. SUMMARY

[0008] In view of this, in order to solve the problems raised in the background art, a centralized oil supply temperature control system for a plastic pipe production workshop is proposed.

[0009] The purposes of the present application can be realized by the following technical solutions: a centralized oil supply temperature control system for a plastic pipe production workshop, comprising: an oil liquid centralized heating module, which analyzes the initial heating temperature of the centralized heating main pipeline based on the required temperature of each distributed device and a pre-constructed pipeline size-temperature loss mapping relationship, and heats the heat conducting oil in the main pipeline to the initial heating temperature by using a heating device.

[0010] An oil liquid secondary temperature control module, which sets a temperature control device near the oil liquid input direction branch pipeline of each distributed device, controls the input end temperature based on the measured input oil temperature, and records and constructs a temperature control data set in real time, specifically including the temperature control direction and the temperature control amplitude.

[0011] An oil liquid backflow temperature control module, which sets a backflow temperature control device on each branch pipeline near the oil liquid collection point, identifies the oil liquid collection target temperature based on the measured output oil temperature, calibrates the branch pipeline that needs to be controlled at the output end, and controls the oil liquid backflow temperature of the branch pipeline.

[0012] A centralized heating correction module, which determines whether the initial heating temperature of the heating main pipeline needs to be regulated based on the temperature control data set, and outputs the regulated initial heating temperature if needed.

[0013] Compared with the prior art, the present application has the following advantages: (1) The present application calculates the initial heating temperature by constructing a pipeline size-temperature loss mapping relationship and combining the required temperature of each branch, reduces the oil temperature loss deviation caused by pipeline differences, reduces the adjustment pressure of secondary temperature control, and improves the adaptability of the initial heating temperature.

[0014] (2) The present application monitors and corrects the input end oil temperature in real time through the secondary temperature control module, ensures that the actual working temperature of each device is consistent with the required temperature, and directly improves the stability of the quality of plastic pipe products.

[0015] (3) The present application avoids the decrease of circulation efficiency or damage to equipment caused by too large temperature difference of backflow oil liquid through optimization of target temperature and targeted regulation, prolongs the service life of the system, and improves the controllability of the backflow oil liquid collection temperature.

[0016] (4) The present application dynamically adjusts the temperature of the main pipeline according to the actual temperature control data through the centralized heating correction module, reduces invalid temperature control operations, and reduces energy consumption; at the same time, the system can adapt to different sizes of branch and equipment requirements, and has strong universality. BRIEF DESCRIPTION OF DRAWINGS

[0017] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiment description. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creating any creative labor.

[0018] Figure 1 The schematic diagram of the connection of each module of the system of the present application.

[0019] Figure 2 The schematic diagram of the dynamic adaptation analysis process based on the reference temperature corresponding to an embodiment provided by the present application.

[0020] Figure 3 The schematic diagram of the matching analysis process based on the temperature range and the equipment capacity corresponding to an embodiment provided by the present application. DETAILED DESCRIPTION

[0021] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0022] Please refer to Figure 1 As shown in the figure, the present application provides a centralized oil supply temperature control system for a plastic pipe production workshop, an oil liquid centralized heating module, an oil liquid secondary temperature control module, an oil liquid backflow temperature control module and a centralized heating correction module, wherein the oil liquid centralized heating module is connected with the oil liquid secondary temperature control module, the oil liquid secondary temperature control module is connected with the oil liquid backflow temperature control module, and the oil liquid backflow temperature control module is connected with the centralized heating correction module.

[0023] The oil liquid centralized heating module analyzes the initial heating temperature of the centralized heating main pipeline based on the required temperature of each distributed equipment and a pre-constructed pipeline size-temperature loss mapping relationship, and uses a heating device to heat the heat conducting oil in the main pipeline to the initial heating temperature.

[0024] It needs to be explained that the reason for analyzing the initial heating temperature of the centralized heating main pipeline based on the required temperature of each distributed equipment and the pre-constructed pipeline size-temperature loss mapping relationship is that different branch pipeline sizes will cause different temperature losses in the heat conducting oil transmission. The mapping relationship can quantify this loss, and combined with the equipment required temperature, the initial temperature required by each branch can be determined. Based on this, the initial heating temperature of the main pipeline is analyzed, which can ensure that the oil temperature of the heat conducting oil after transmission loss is close to the required value when reaching each equipment, reduce the burden of subsequent secondary temperature control, improve the temperature control accuracy and efficiency of the system, and avoid energy waste and unstable equipment operation caused by unreasonable initial temperature.

[0025] In a preferred embodiment of the present application, the specific construction method of the pipeline size-temperature loss mapping relationship is as follows: collect the pipeline size information of each branch pipeline in the plastic pipe production workshop, including the length, diameter, material thickness and other key parameters of the pipeline.

[0026] Different sizes of branch pipes were selected as test objects. Heat transfer oil at a specific temperature was introduced at the starting point of each test branch pipe, and the oil flow rate was kept stable.

[0027] Temperature detection devices are installed at the end of each test pipeline to monitor and record the actual temperature of the oil flowing through the pipeline in real time. The difference between the starting temperature and the ending temperature is calculated to obtain the temperature loss value corresponding to the pipeline size.

[0028] By changing to test pipes of different sizes, repeat the above steps of inputting oil at a specific temperature, monitoring the endpoint temperature, and calculating the temperature loss, and accumulate multiple sets of data on pipe dimensions and corresponding temperature losses.

[0029] The collected data were organized to establish the correspondence between pipeline size parameters and temperature loss values, forming a pipeline size-temperature loss mapping relationship.

[0030] It should be noted that the reason for establishing the pipeline size-temperature loss mapping relationship is as follows: 1. To solve the problem of inconsistent temperature loss caused by differences in pipelines. Within the plastic pipe production workshop, the length, diameter, and material thickness of each branch pipeline vary, and these differences directly affect the heat loss of the heat transfer oil during transmission. By establishing this mapping relationship, the temperature loss value corresponding to different pipeline sizes can be quantified, avoiding oil temperature deviations caused by different pipeline characteristics.

[0031] 2. To provide a basis for calculating the initial heating temperature, the initial heating temperature of the centralized heating main pipeline needs to be adjusted based on the required temperature of each distributed device, combined with the temperature loss of the branch pipelines. If there is a lack of correspondence between pipeline size and temperature loss, it is impossible to accurately estimate the heat loss of different branches, which will lead to unreasonable initial heating temperature settings, and consequently cause problems such as large deviations in oil temperature of subsequent branches and frequent secondary temperature control.

[0032] 3. Reduce secondary temperature control load and improve system efficiency. The mapping relationship can predict the temperature loss of each branch in advance, so that the initial heating temperature of the main pipeline is closer to the actual needs of each branch. This reduces the oil temperature deviation at the input end of the branch from the source, reduces the adjustment frequency and amplitude of the secondary temperature control module, thereby saving energy and extending the life of the temperature control equipment.

[0033] It should be further explained that stratified sampling can be used to select typical pipeline size combinations as test objects, prioritizing the coverage of commonly used sizes and extreme values ​​of key parameters with a high proportion in the workshop, thereby reducing the amount of testing. For untested size combinations, temperature loss values ​​are predicted based on existing data using interpolation methods or machine learning models, and then corrected by a small number of validation tests. At the same time, pipeline size parameters are normalized to simplify variable dimensions and reduce data complexity, thereby solving the problem of construction difficulties caused by too many size combination groups while ensuring the accuracy of the mapping relationship.

[0034] In another embodiment, temperature loss testing is performed only on branch pipelines with corresponding dimensions in the factory workshop, thereby constructing a targeted pipeline size-temperature loss mapping relationship.

[0035] In a preferred embodiment of the present invention, the specific analysis method for the initial heating temperature of the centralized heating main pipeline is as follows: the pipeline size of each branch pipeline is matched with the pipeline size-temperature loss mapping relationship to obtain the initial heating temperature correction amount of each branch pipeline.

[0036] The initial required temperature of each branch pipeline is obtained by summing the initial heating temperature correction of each branch pipeline with the required temperature of the corresponding distributed equipment.

[0037] It should be noted that summing the initial heating temperature correction for each branch pipeline with the required temperature of the corresponding distributed equipment is to obtain the temperature that the heat transfer oil needs to reach when it exits the main pipeline to the starting point of that branch. This is because the initial heating temperature correction represents the temperature loss caused by the dimensional characteristics of the branch pipeline, while the equipment required temperature is the target temperature that the heat transfer oil must meet when it reaches the equipment. Summing the two ensures that after the heat transfer oil enters the branch from the main pipeline, due to the temperature loss during the transmission process, the oil temperature when it finally reaches the equipment is close to the required temperature. This reduces the adjustment pressure for subsequent precise temperature control and is a key calculation step in balancing the centralized heating of the main pipeline and the individual needs of the branches.

[0038] Arrange the initial required temperatures of each branch pipeline from highest to lowest, and select the median as the initial heating temperature of the centralized heating main pipeline.

[0039] It should be noted that the median value was selected as the initial heating temperature of the main pipeline after arranging the initial demand temperatures of each branch from highest to lowest. This is because the median balances the demands of different branches and avoids the influence of extreme values. If the maximum value were selected, most branches would have excessively high oil temperatures requiring cooling, increasing energy consumption; if the minimum value were selected, most branches would have insufficient oil temperatures requiring heating, which is also inefficient. The median value ensures that the initial demand temperatures of about half of the branches are close to the temperature of the main pipeline, reducing the overall temperature control adjustment range and frequency. While meeting the basic requirements of most equipment, it reduces the system load and balances temperature control efficiency and energy consumption.

[0040] It should be further explained that the reason for choosing the median instead of the mean in this invention is that the initial demand temperature of each branch may have extreme values ​​due to differences in pipe size. If the average value is used, it will be affected by extreme values ​​and biased too high or too low, resulting in increased oil temperature deviation in most branches and increasing the burden on secondary temperature control. The median, on the other hand, is not affected by extreme values ​​and can reflect the intermediate level, so that the initial demand temperature of about half of the branches is close to the main pipe temperature, reducing the overall adjustment range, which is more in line with the temperature control goal of balancing the demand of most branches and reducing the system load, thus taking into account both efficiency and stability.

[0041] It should be noted that this invention reduces the deviation in oil temperature loss caused by differences in pipelines by constructing a pipeline size-temperature loss mapping relationship and calculating the initial heating temperature in combination with the required temperature of each branch, thereby reducing the adjustment pressure of secondary temperature control and improving the adaptability of the initial heating temperature.

[0042] The secondary oil temperature control module sets up temperature control devices on the branch pipelines near the oil input direction of each distributed device. It performs input temperature control based on the measured input oil temperature, records and constructs a temperature control dataset in real time, which specifically includes the temperature control direction and temperature control amplitude.

[0043] In a preferred embodiment of the present invention, the specific method for performing input end temperature control is as follows: the measured input oil temperature of each branch pipeline is compared with the required temperature of each distributed device. If the relative deviation between the measured input oil temperature and the required temperature of the distributed device exceeds the limit, it is determined that input end temperature control is required.

[0044] In one embodiment, when comparing the measured input oil temperature of each branch pipeline with the required temperature of each distributed device, an analysis is performed by setting a relative deviation threshold. The relative deviation threshold is set based on two factors: first, the actual requirements of the plastic pipe production equipment for oil temperature accuracy, which must be combined with the process standards of different equipment to ensure that the oil temperature deviation does not affect product quality; second, the adjustment capability of the temperature control equipment, the threshold must match the temperature control accuracy that the equipment can achieve, to avoid frequent start-ups or adjustment failures due to the threshold being too small, while also taking into account energy consumption and control efficiency, and finally determining a reasonable range through experimental verification.

[0045] If the measured input oil temperature is greater than the required temperature of the distribution equipment, the temperature control direction is determined to be cooling, and the difference between the measured input oil temperature and the required temperature of the distribution equipment is recorded as the temperature control amplitude of the corresponding input end temperature control.

[0046] If the measured input oil temperature is lower than the required temperature of the distribution equipment, the temperature control direction is determined to be heating. The difference between the required temperature of the distribution equipment and the measured input oil temperature is recorded as the temperature control amplitude of the corresponding input terminal temperature control.

[0047] It should be noted that this invention monitors and corrects the input oil temperature in real time through a secondary temperature control module, ensuring that the actual operating temperature of each device is consistent with the required temperature, thereby directly improving the stability of the quality of plastic pipe products.

[0048] The oil reflux temperature control module installs reflux temperature control devices on each branch pipeline near the oil collection point. Based on the measured output oil temperature, it identifies the target temperature of the oil collection, calibrates the branch pipelines that need output temperature control, and performs oil reflux temperature control on them.

[0049] It's important to explain that oil reflux temperature control is necessary because the output oil temperatures of each branch pipeline differ. Directly collecting these temperatures would cause drastic overall temperature fluctuations, affecting the heat transfer oil circulation efficiency and potentially leading to pipe scaling and equipment damage due to excessive local temperature differences. By identifying and adjusting the target collection temperature, the output oil temperatures of each branch can be made more uniform, reducing energy loss and temperature shocks during collection, ensuring stable operation of the circulation system, and providing a stable initial temperature for subsequent heat transfer oil reuse. This reduces energy consumption for reheating or cooling, improving the economy and safety of the entire centralized oil supply system.

[0050] In a preferred embodiment of the present invention, the specific method for identifying the target temperature of the oil collection is as follows: obtain the measured output oil temperature of each branch pipeline, take the measured output oil temperature of any branch pipeline as the reference output oil temperature, and calculate the sum of the actual temperature adjustment spans of the other branch pipelines adjusted to the reference output oil temperature.

[0051] The actual output oil temperature of each branch pipeline is calculated as the sum of the actual temperature adjustment spans corresponding to the reference output oil temperature.

[0052] The sum of each actual temperature adjustment span is compared, and the reference output oil temperature corresponding to the smallest sum of actual temperature adjustment spans is selected as the target temperature for oil collection.

[0053] It's important to explain that by comparing the sum of all actual temperature adjustment spans, the minimum total output oil temperature is selected as the target temperature. The core principle is to achieve efficient reflux temperature control by minimizing overall temperature adjustment costs. The sum of the actual temperature adjustment spans reflects the total workload of adjusting the output oil from all branches to a certain reference temperature. The smaller the sum, the smaller the overall temperature adjustment range required for each branch. Using this as the target temperature minimizes the adjustment load on the reflux temperature control equipment, reduces energy consumption, and avoids oil temperature fluctuations caused by large temperature adjustments. This ensures stable temperature when the output oil from each branch converges, improves the operating efficiency and stability of the heat transfer oil circulation system, and lays a good foundation for subsequent oil reuse.

[0054] In a preferred embodiment of the present invention, the specific method for calibrating the branch that requires output end temperature control is as follows: the measured output oil temperature of each branch pipeline is compared with the reference output oil temperature to determine whether the deviation between the measured output oil temperature of each branch pipeline and the reference output oil temperature exceeds the limit.

[0055] If the measured output oil temperature of a branch pipeline deviates from the reference output oil temperature beyond the limit, then the branch pipeline is designated as a branch pipeline that requires output end temperature control; otherwise, it is determined that output end temperature control is not required.

[0056] The specific method for determining whether the deviation between the measured output oil temperature and the reference output oil temperature of each branch pipeline exceeds the limit is as follows: calculate the absolute difference between the measured output oil temperature and the reference output oil temperature of each branch pipeline, compare the result with the preset output oil temperature deviation threshold, and if the result is greater than the output oil temperature deviation threshold, it is determined that the deviation between the measured output oil temperature and the reference output oil temperature of the branch pipeline exceeds the limit; otherwise, it is determined that the deviation between the measured output oil temperature and the reference output oil temperature of the branch pipeline does not exceed the limit.

[0057] It should be noted that the output oil temperature deviation threshold is a critical value used to determine whether the deviation between the branch pipeline's output oil temperature and the target convergence temperature needs to be adjusted. Its setting is based on two aspects: first, the stability requirements of the heat transfer oil circulation system; if the deviation is too large, it can easily cause drastic temperature fluctuations during convergence, affecting pipeline lifespan and circulation efficiency; second, the adjustment capability of the return flow temperature control equipment, avoiding a threshold that is too small leading to frequent start-ups and shutdowns, or too large causing temperature control failure. It is usually determined experimentally, for example, based on the system's tolerance range for convergence temperature fluctuations. If this value is exceeded, it is determined that output temperature control of the branch is necessary to ensure that the return flow oil temperature approaches the target, balancing control accuracy and system load.

[0058] For a preferred embodiment of the present invention, please refer to Figure 2 , 3 As shown, when performing oil reflux temperature control, it is necessary to determine whether the reflux temperature control equipment has temperature control capability. The specific analysis method is as follows: A1. Calculate the difference between the measured output oil temperature of each branch pipeline and the reference output oil temperature, and then compare it with the maximum temperature control capability of the reflux temperature control equipment of each branch pipeline.

[0059] A2. If the calculated difference between the measured output oil temperature and the reference output oil temperature of all branch pipelines is less than the maximum temperature control capability of the corresponding reflux temperature control device, the reflux temperature control device is deemed to have temperature control capability.

[0060] A3. If the calculated difference between the measured output oil temperature and the reference output oil temperature in any branch pipeline is greater than the maximum temperature control capacity of the corresponding reflux temperature control device, then adjust the reference output oil temperature.

[0061] A4. Based on the adjusted reference output oil temperature, re-analyze until the reference output oil temperature is equal to half of the sum of the maximum measured output oil temperature and the minimum measured output oil temperature. If the calculated difference between the measured output oil temperature and the reference output oil temperature of any branch pipeline is still greater than the maximum temperature control capability of the corresponding reflux temperature control device, then it is determined that the reflux temperature control device does not have temperature control capability.

[0062] It needs to be explained that when the temperature difference in some branches exceeds the maximum temperature control capability of the equipment, the reference output oil temperature is adjusted to try to match the equipment capability. Theoretically, half of the sum of the maximum and minimum measured output oil temperatures is the most balanced reference point. If, under this optimal reference, the measured output oil temperature of a branch still exceeds the maximum temperature control capability of the corresponding equipment, it means that even if the most reasonable target temperature is selected, the equipment cannot meet the control requirements of all branches. In this case, it is determined that the return flow temperature control equipment does not have the temperature control capability, and other methods, such as replacing the equipment or adjusting the system, are needed to solve the problem.

[0063] B1. Compare the measured output oil temperatures of each branch pipeline, and calculate the difference between the maximum and minimum measured output oil temperatures to obtain the measured output oil temperature range.

[0064] B2. The maximum temperature control capability is obtained by summing the maximum measured output oil temperature and the minimum measured output oil temperature.

[0065] B3. Compare the measured output oil temperature range with the maximum temperature control capability limit. If the measured output oil temperature range is greater than the maximum temperature control capability limit, it is determined that the reflux temperature control device does not have temperature control capability; otherwise, it is determined that the reflux temperature control device has temperature control capability.

[0066] It should be noted that this invention combines two methods to determine the capability of reflux temperature control equipment: dynamic adaptability analysis based on a reference temperature and matching analysis based on temperature range and equipment capability. The advantage lies in balancing accuracy and comprehensiveness. Dynamic adaptability analysis verifies the equipment's adaptability to different target temperatures by adjusting the reference temperature, avoiding misjudgments caused by a single reference. Matching analysis directly assesses the overall control range coverage by comparing the sum of the oil temperature range and the equipment capability. The combination of these two methods considers both the optimized adaptability to the target temperature and the equipment's extreme capabilities under extreme temperature differences, allowing for a more comprehensive check of whether the equipment can meet the control needs of all branches. This reduces temperature control failures caused by oversights in a single judgment method and ensures the reliability of oil reflux temperature control.

[0067] In a preferred embodiment of the present invention, the maximum temperature control capability of the return flow temperature control device for each branch pipeline is specifically achieved as follows: a large number of return flow temperature control tests are conducted on each branch pipeline, heat transfer oil at different temperatures is input, the temperature is controlled using the return flow temperature control device, and the output heat transfer oil temperature after the actual temperature control test is calculated.

[0068] The actual temperature control range corresponding to the temperature control test of each return flow temperature control device is obtained by calculating the difference between the temperature of the input heat transfer oil and the temperature of the output heat transfer oil.

[0069] The maximum temperature control capacity of each branch pipeline's return flow temperature control equipment is obtained by averaging the actual temperature control amplitudes corresponding to the temperature control tests of each return flow temperature control equipment.

[0070] In a preferred embodiment, when analyzing the maximum temperature control capability of the return flow temperature control equipment in each branch pipeline, the effects of heat loss in the branch pipeline and oil flow rate fluctuations on the control effect are also considered.

[0071] It should be noted that this invention optimizes the target temperature and implements targeted control to avoid a decrease in circulation efficiency or equipment damage caused by excessive temperature differences in the return oil, thereby extending the system's service life and improving the controllability of the return oil collection temperature.

[0072] The centralized heating correction module determines whether the initial heating temperature of the main heating pipe needs to be adjusted based on the temperature control dataset. If so, it outputs the adjusted initial heating temperature.

[0073] In a preferred embodiment of the present invention, the specific method for determining whether the initial heating temperature of the main heating pipe needs to be adjusted is as follows: extract the temperature control dataset and obtain the temperature control direction and temperature control amplitude corresponding to each temperature control dataset.

[0074] The average temperature control amplitude is calculated by averaging the temperature control amplitudes of each temperature control dataset. This average amplitude is then compared with a preset threshold. If the average temperature control amplitude is greater than the preset threshold, it is determined that the initial heating temperature of the main heating pipe needs to be adjusted; otherwise, it is determined that the initial heating temperature of the main heating pipe does not need to be adjusted.

[0075] It should be explained that the temperature control amplitude of each temperature control dataset reflects the actual temperature difference that each branch needs to adjust at the input or output end, and its average value can represent the overall temperature control load of the system. If the average temperature control amplitude is greater than the preset threshold, it indicates that most branches require a large temperature adjustment, indirectly indicating that the initial heating temperature of the main pipeline is poorly matched with the actual needs of each branch. In this case, the deviation needs to be reduced from the source by adjusting the initial temperature of the main pipeline. Conversely, if the average amplitude is lower than the threshold, it indicates that the overall temperature control load is small, and the initial temperature of the main pipeline basically matches the needs of each branch, without the need for additional adjustment.

[0076] In a preferred embodiment, an analysis process is provided for setting a temperature control amplitude threshold based on historical operating data statistics: First, the temperature control amplitude of each temperature control dataset during stable system operation is collected, extreme outliers are removed, and the average temperature control amplitude for different time periods is calculated and a distribution range is formed. The maximum average amplitude value under more than 90% normal operating conditions is statistically analyzed, and this is used as a benchmark, with an additional 10%-20% redundancy added as a preset threshold. During comparison, if the current average temperature control amplitude exceeds this threshold, it indicates that the initial temperature of the main pipeline has decreased in match with the branch demand, and adjustment is required; otherwise, no adjustment is needed. This avoids frequent adjustments and ensures that the system is stable and efficient under most historical operating conditions.

[0077] In a preferred embodiment of the present invention, the specific method for adjusting the initial heating temperature after output is as follows: calculate the average temperature rise amplitude of the temperature control dataset with the temperature control direction of rising, calculate the average temperature drop amplitude of the temperature control dataset with the temperature control direction of falling, and compare the average temperature rise amplitude with the average temperature drop amplitude.

[0078] If the average temperature rise range is greater than the average temperature fall range, the difference between the average temperature rise range and the average temperature fall range is used as the initial heating temperature correction amount. Then, the initial heating temperature and the initial heating temperature correction amount are summed to calculate the adjusted initial heating temperature.

[0079] If the average temperature rise range is less than the average temperature fall range, the difference between the average temperature rise range and the average temperature fall range is used as the initial heating temperature correction amount. Then, the difference between the initial heating temperature and the initial heating temperature correction amount is used to calculate the adjusted initial heating temperature.

[0080] It should be noted that the present invention dynamically adjusts the temperature of the main pipeline based on actual temperature control data through a centralized heating correction module, reducing ineffective temperature control operations and lowering energy consumption; at the same time, the system can be adapted to the needs of different sized branches and equipment, and has strong versatility.

[0081] It should be noted that while secondary oil temperature control can be performed, temperature control capability analysis can also be conducted. However, in actual operation, considering that secondary oil temperature control is close to the initial main pipeline oil heating operation, the situation of being unable to perform secondary oil temperature control beyond the limit is generally unlikely. Therefore, this invention does not list it. However, in actual production, if the secondary oil temperature control capability exceeds the limit due to usage time and mechanical aging, the relevant equipment can be analyzed and warnings can be issued separately.

[0082] The above content is merely an example and illustration of the concept of the present invention. Those skilled in the art can make various modifications or additions to the specific embodiments described, or use similar methods to replace them, as long as they do not deviate from the concept of the invention or exceed the scope defined by the present invention, and all such modifications and additions should fall within the protection scope of the present invention.

Claims

1. A centralized oil supply temperature control system for a plastic pipe production plant, characterized by, The application relates to a centralized heating system for heat conduction oil, which comprises the following modules: an oil liquid centralized heating module, which analyzes an initial heating temperature of a centralized heating main pipeline based on required temperatures of various distributed devices and a pre-constructed pipeline size-temperature loss mapping relationship, and heats heat conduction oil in the main pipeline to the initial heating temperature by using a heating device; an oil liquid secondary temperature control module, which sets a temperature control device on a branch pipeline close to an oil liquid input direction of each distributed device, performs input end temperature control based on a measured input oil temperature, and records and constructs a temperature control data set in real time, and the temperature control data set specifically comprises a temperature control direction and a temperature control amplitude; an oil liquid backflow temperature control module, which sets a backflow temperature control device on each branch pipeline close to an oil liquid collection point, identifies an oil liquid collection target temperature based on a measured output oil temperature, calibrates a branch pipeline needing output end temperature control, and performs oil liquid backflow temperature control on the branch pipeline; a centralized heating correction module, which judges whether the initial heating temperature of the main pipeline needs to be regulated based on the temperature control data set, and outputs the regulated initial heating temperature if the initial heating temperature needs to be regulated.

2. The centralized oil supply temperature control system for a plastic pipe production plant according to claim 1, characterized in that: The pipeline size-temperature loss mapping relationship is constructed in the following manner: pipeline size information of each branch pipeline in a plastic pipe production workshop is collected, including key parameters such as the length, diameter and material thickness of the pipeline; branch pipelines with different sizes are selected as test objects, heat conduction oil with a specific temperature is input at the starting point of each test branch pipeline, and the oil liquid flow is kept stable; a temperature detection device is arranged at the end of each test pipeline, the actual temperature of the oil liquid after flowing through the pipeline is monitored and recorded in real time, the difference between the starting point temperature and the end point temperature is calculated, and the temperature loss value corresponding to the pipeline size is obtained; different size test pipelines are replaced, and the above operations of inputting oil liquid with a specific temperature, monitoring the end point temperature and calculating the temperature loss are repeated, and multiple groups of pipeline size and corresponding temperature loss data are accumulated; the collected multiple groups of data are sorted, the corresponding relationship between the pipeline size parameter and the temperature loss value is established, and the pipeline size-temperature loss mapping relationship is formed.

3. The centralized oil supply temperature control system for a plastic pipe production plant according to claim 1, characterized in that: The initial heating temperature of the centralized heating main pipeline is analyzed in the following manner: the pipeline size of each branch pipeline is matched with the pipeline size-temperature loss mapping relationship to obtain an initial heating temperature correction amount of each branch pipeline; the initial heating temperature correction amount of each branch pipeline is summed with the required temperature of each distributed device to obtain an initial required temperature of each branch pipeline; the initial required temperatures of the branch pipelines are arranged from large to small, and the median is selected as the initial heating temperature of the centralized heating main pipeline.

4. The centralized oil supply temperature control system for a plastic pipe production plant according to claim 1, characterized in that: The input end temperature control is performed in the following manner: the measured input oil temperature of each branch pipeline is compared with the required temperature of each distributed device, and if the relative deviation degree of the measured input oil temperature and the required temperature of the distributed device is out of limit, it is judged that the input end temperature control needs to be performed; if the measured input oil temperature is greater than the required temperature of the distributed device, it is judged that the temperature control direction is cooling, and the difference between the measured input oil temperature and the required temperature of the distributed device is recorded as the temperature control amplitude of the corresponding input end temperature control; if the measured input oil temperature is less than the required temperature of the distributed device, it is judged that the temperature control direction is heating, and the difference between the required temperature of the distributed device and the measured input oil temperature is recorded as the temperature control amplitude of the corresponding input end temperature control.

5. The centralized oil supply temperature control system for a plastic pipe production plant according to claim 1, characterized in that: The oil liquid collection target temperature is identified in the following manner: The measured output oil temperature of each branch pipeline is obtained, and the measured output oil temperature of any branch pipeline is taken as a reference output oil temperature, and the sum of actual temperature adjustment spans of other branch pipelines adjusted to the reference output oil temperature is calculated; The sum of each actual temperature adjustment span corresponding to the measured output oil temperature of each branch pipeline taken as the reference output oil temperature is calculated; The sum of the actual temperature adjustment spans is compared, and the reference output oil temperature corresponding to the minimum sum of the actual temperature adjustment spans is selected as the oil collection target temperature.

6. The centralized oil supply temperature control system for a plastic pipe production plant according to claim 5, characterized in that: The specific mode of the calibration of the branch needing output end temperature control is as follows: The measured output oil temperature of each branch pipeline is compared with the reference output oil temperature, and it is determined whether the deviation of the measured output oil temperature of each branch pipeline from the reference output oil temperature is out of limit; If it is determined that the deviation of the measured output oil temperature of the branch pipeline from the reference output oil temperature is out of limit, the branch pipeline is calibrated as the branch pipeline needing output end temperature control, otherwise, it is determined that output end temperature control is not needed; The specific mode of the determination of whether the deviation of the measured output oil temperature of each branch pipeline from the reference output oil temperature is out of limit is as follows: the absolute difference value of the measured output oil temperature of each branch pipeline from the reference output oil temperature is calculated, and the result is compared with a preset output oil temperature deviation threshold value; if the result is greater than the output oil temperature deviation threshold value, it is determined that the deviation of the measured output oil temperature of the branch pipeline from the reference output oil temperature is out of limit, otherwise, it is determined that the deviation of the measured output oil temperature of the branch pipeline from the reference output oil temperature is not out of limit.

7. The centralized oil supply temperature control system for a plastic pipe production plant according to claim 6, characterized in that: When the oil return temperature control is performed, it is needed to determine whether the return temperature control equipment has temperature control capability, and the specific analysis mode is as follows: A1, the difference value of the measured output oil temperature of each branch pipeline from the reference output oil temperature is calculated, and then compared with the maximum temperature control capability of the return temperature control equipment of each branch pipeline; A2, if the difference value calculation result of the measured output oil temperature of all branch pipelines from the reference output oil temperature is less than the maximum temperature control capability of the corresponding return temperature control equipment, it is determined that the return temperature control equipment has temperature control capability; A3, if the difference value calculation result of the measured output oil temperature of any branch pipeline from the reference output oil temperature is greater than the maximum temperature control capability of the corresponding return temperature control equipment, the reference output oil temperature is adjusted; A4, based on the adjusted reference output oil temperature, the analysis is re-performed until the reference output oil temperature is equal to half of the sum of the maximum measured output oil temperature and the minimum measured output oil temperature, and there is still any branch pipeline whose difference value calculation result of the measured output oil temperature from the reference output oil temperature is greater than the maximum temperature control capability of the corresponding return temperature control equipment, it is determined that the return temperature control equipment does not have temperature control capability; B1, the measured output oil temperatures of each branch pipeline are compared, and the difference value of the maximum measured output oil temperature and the minimum measured output oil temperature is calculated to obtain the measured output oil temperature range; B2, the maximum temperature control capability corresponding to the maximum measured output oil temperature and the minimum measured output oil temperature is summed to obtain the maximum temperature control capability extreme value; B3, the measured output oil temperature range is compared with the maximum temperature control capability extreme value; if the measured output oil temperature range is greater than the maximum temperature control capability extreme value, it is determined that the return temperature control equipment does not have temperature control capability, otherwise, it is determined that the return temperature control equipment has temperature control capability.

8. The centralized oil supply temperature control system for a plastic pipe production plant according to claim 7, characterized in that: The maximum temperature control capability of each branch pipeline backflow temperature control device is specifically as follows: A large number of backflow temperature control device temperature control tests are performed on each branch pipeline, heat-conducting oil of different temperatures is input, temperature control is performed by using the backflow temperature control device, and the output heat-conducting oil temperature after actual temperature control test is calculated; The temperature of the input heat-conducting oil and the output heat-conducting oil temperature are calculated by difference to obtain the actual temperature control range corresponding to each backflow temperature control device temperature control test; The actual temperature control range corresponding to each backflow temperature control device temperature control test is calculated by mean value to obtain the maximum temperature control capability of each branch pipeline backflow temperature control device.

9. The centralized oil supply temperature control system for a plastic pipe production plant according to claim 1, characterized in that: The specific method for determining whether the initial heating temperature of the heating main pipeline needs to be regulated is as follows: Extract the temperature control data set, obtain the temperature control direction and temperature control range corresponding to each temperature control data set; The average temperature control range is calculated by averaging the temperature control range of each temperature control data set, and compared with the preset threshold value. If the average temperature control range is greater than the preset threshold value, it is determined that the initial heating temperature of the heating main pipeline needs to be regulated, otherwise, it is determined that the initial heating temperature of the heating main pipeline does not need to be regulated.

10. The centralized oil supply temperature control system for a plastic pipe production plant according to claim 9, characterized in that: The specific method for outputting the regulated initial heating temperature is as follows: The average temperature control range of the temperature control data set with the temperature control direction of heating is calculated, and the average temperature control range of the temperature control data set with the temperature control direction of cooling is calculated. The average temperature control range of heating is compared with the average temperature control range of cooling; If the average temperature control range of heating is greater than the average temperature control range of cooling, the difference between the average temperature control range of heating and the average temperature control range of cooling is taken as the initial heating temperature correction amount, and then the initial heating temperature and the initial heating temperature correction amount are summed to obtain the regulated initial heating temperature; If the average temperature control range of heating is less than the average temperature control range of cooling, the difference between the average temperature control range of heating and the average temperature control range of cooling is taken as the initial heating temperature correction amount, and then the initial heating temperature and the initial heating temperature correction amount are subtracted to obtain the regulated initial heating temperature.

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