Radiation dose control system and method of use thereof

Abstract

The application discloses an irradiation dose control system, which comprises a medium module, an irradiation container, a conveying device, a PLC controller, an irradiation device and an irradiation chamber. The irradiation dose control system adopts the conveying device to operate the medium module. The medium module is arranged in the irradiation container. The irradiation device is arranged in the irradiation chamber. The irradiation container is conveyed in a full-load mode according to the PLC control program and action instructions. The conveying device conveys the irradiation container into the irradiation chamber and receives gamma ray irradiation. The temperature in the irradiation chamber is controlled to be less than 90 DEG C. The irradiation chamber is provided with a temperature detector, a smoke detector, an audible and visual alarm device and a safety interlock. The application further discloses an application method of the irradiation dose control system. The application can improve the production capacity and greatly increase the economic benefits, conforms to the national low-carbon and energy-saving policy, has considerable comprehensive benefits, realizes the optimization and improvement of the irradiation dose control rate and dose non-uniformity, and greatly improves the energy utilization rate, the irradiation production capacity and the economic benefits.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of gamma irradiation device operation, in particular to an irradiation dose control system and an application method thereof. BACKGROUND

[0002] The installation and commissioning of a gamma irradiation device and the change of the cobalt source each time the installation is increased or decreased, shall be carried out in accordance with the requirements of GB / T17568-2019 standard for equipment operation qualification (OQ) to obtain data to prove that the installed irradiation device is operated within the predetermined equipment operation technical parameters and achieves the irradiation dose range set by the irradiation process for the irradiated medium, thereby improving the accuracy, repeatability and traceability of the irradiation processing dose control, especially playing a technical guarantee and quality guarantee role in process control to ensure the sterilization and sterility assurance level of medical medium modules.

[0003] The data obtained by the irradiation device equipment operation qualification should at least include irradiation container internal dose distribution test data, isodose curve distribution law graph, maximum dose value and equivalent area, minimum dose value and equivalent area, dose non-uniformity DUR, master control time MT parameter, dosimeter placement coordinate point, cobalt source utilization rate SER, processing capacity PT and other data.

[0004] In the process of gamma irradiation sterilization of medical products, in order to ensure that the sterility assurance level (SAL) of medical products after sterilization meets the set requirements, the manufacturer of medical products will determine the irradiation sterilization allowed irradiation dose D value for a certain product according to relevant standards and experiments, i.e. the irradiation allowed minimum dose value and the irradiation allowed maximum dose value; in the irradiation processing practice, the actual irradiation dose will be controlled within this high-low allowed value interval to achieve the expected sterilization within the set dose range. Therefore, the minimization control of the actual irradiation dose within the allowed dose range, so that the minimum and maximum values of the irradiation dose (Dmin~Dmax) are between the allowed range and close to the allowed minimum dose value as much as possible, is the goal pursued by the optimization of irradiation operation dose control and the maximum saving of energy.

[0005] At present, the irradiation dose control rate of domestic industrial irradiation devices is about 10-15%, the irradiation dose non-uniformity is about 12-17%, the irradiation dose non-uniformity is relatively low, the actual effect of irradiation dose control is poor, and the energy utilization rate is low. Whether the determination of the irradiation medium as the carrier of the irradiation dose in the operation qualification dose field test process meets the irradiation process requirements and represents the relevant parameters of the absorption of the irradiation dose by all irradiated medium modules and carries out dose field test and mathematical analysis in a systematic way is one of the key links and difficulties in the irradiation device equipment operation qualification process. SUMMARY

[0006] In order to solve the above technical problems, the technical scheme adopted by the present application is:

[0008] The present application provides an irradiation dose control system and its application method, which provides theoretical and practical support for the operation control of large-scale irradiation devices, and provides a stable, optimized and operable scheme for irradiation dose control, which can improve the irradiation dose control rate (DCR) by 2-7%, and optimize the dose uniformity (DUR) by 3-8%, thereby improving productivity and greatly increasing economic benefits, meeting the national low-carbon and energy-saving policy, and achieving comprehensive benefits, and realizing the optimization and improvement of the irradiation dose control rate and the dose uniformity, which actually greatly improves the optimization and improvement level of energy utilization rate, irradiation productivity and economic benefits.

[0007] In order to solve the above technical problems, the technical scheme adopted by the present application is:

[0008] The present application provides an irradiation dose control system and its application method, which provides theoretical and practical support for the operation control of large-scale irradiation devices, and provides a stable, optimized and operable scheme for irradiation dose control, which can improve the irradiation dose control rate (DCR) by 2-7%, and optimize the dose uniformity (DUR) by 3-8%, thereby improving productivity and greatly increasing economic benefits, meeting the national low-carbon and energy-saving policy, and achieving comprehensive benefits, and realizing the optimization and improvement of the irradiation dose control rate and the dose uniformity, which actually greatly improves the optimization and improvement level of energy utilization rate, irradiation productivity and economic benefits.

[0009] The conveying device adopts a running mode of a roller conveying double-layer bidirectional four-channel automatic layer-changing and surface-changing cover source to run the irradiation container and the medium module arranged in the irradiation container.

[0010] In order to solve the above technical problems, the technical scheme adopted by the present application is:

[0011] Further, the irradiation mode of the irradiation container is that from the irradiation position of the first irradiation container entering the irradiation room to the irradiation position of the last irradiation container entering the irradiation room, the irradiation processing is completed and the irradiation position of the irradiation container leaving the irradiation room, that is, one irradiation cycle.

[0012] Further, in one irradiation cycle, the number of the irradiation containers is greater than or equal to the number of the positions of the irradiation room.

[0013] Further, the continuous operation mode of the irradiation device is that: arrange the master control time of several irradiation containers to be irradiated in the current period which conform to the general principle of the series to form an irradiation cycle, control the irradiation device to carry out irradiation processing through the PLC controller, and then the next irradiation cycle is carried out after the irradiation processing is completed.

[0014] The application also provides an application method of the irradiation dose control system, which comprises the combination sorting principle and method of the irradiation device operation control parameter and the evaluation method and the medium module processing irradiation cycle.

[0015] The irradiation device operation control parameter and the evaluation method comprise the following steps:

[0016] S1: obtaining the theoretical master control time T of the medium module processing 理论 : according to the formula, the theoretical master control time value of the medium module processing is obtained, that is, the time of the irradiation container running from one irradiation station to the next irradiation station through the PLC control program of the irradiation device + the residence time in the next irradiation station;

[0017] S2: determining the reference time T 基 : select a representative medium module and take the corresponding irradiation processing master control time T 主 as the reference time value, and the representative medium module meets the selection principle;

[0018] S3: determining the decomposition time T 分 : before irradiation processing, in order to meet the needs of the combination sorting of the irradiation cycle, the theoretical master control time T 理论 of the medium module is reduced by a reference time through formula a to obtain the decomposition time T 分 , and the decomposition time T 分 follows the uniform common operation control time parameter T 共 in the combination sorting of the irradiation cycle.

[0019] T 分 = T 理论 -T 基 formula a;

[0020] In the formula:

[0021] T 基 is the reference time;

[0022] T 理论 is the theoretical master control time;

[0023] T 分 is the decomposition time;

[0024] S4: Execute the irradiation cycle: group several irradiation containers loaded with different media modules according to the same actual master control time. The cycle continues from the first irradiation container entering the irradiation station in the irradiation chamber to the last irradiation container completing the irradiation process and leaving the irradiation station in the irradiation chamber.

[0025] A single irradiation cycle consists of an irradiation cycle starter, several irradiation containers, and an irradiation cycle tailer, all operating under the same actual master control time.

[0026] Among them, the first irradiation container of an irradiation cycle is defined as the first irradiation container processed into an irradiation cycle according to the same decomposition master control time.

[0027] Irradiation cycle tail box: The last irradiation container processed into an irradiation cycle according to the same decomposition master control time is defined as the irradiation cycle tail box;

[0028] The combination and sequencing principles and methods for the processing irradiation cycles of the medium module include the following steps:

[0029] S10: Arrange the main control time of several products to be irradiated that conform to the general term formula of the sequence in the current period into a sequence to form an irradiation cycle. Then, control the irradiation device to perform irradiation processing through the PLC controller. After the cycle is completed, the next irradiation cycle is continued to realize the continuous operation of the irradiation device.

[0030] The general formula for the sequence follows this principle: an irradiation cycle has a master control time, the value of which lies between the master control time Tmin corresponding to the minimum allowable irradiation dose of all products in the cycle and the master control time Tmax corresponding to the maximum allowable irradiation dose, as shown in inequality b. In the sequence, the values ​​of each sub-term T... 主 Decompose into constant T 基 +Variable T 分 , deduct T 基 The remaining time value is defined as the decomposition time T. 分 T 分 ≥T 步 That is, the decomposition time is greater than or equal to the stepping action time of the irradiation device when scheduling orders;

[0031] Tmin≤T 基 +T 分 The inequality b ≤ Tmax;

[0032] In the formula:

[0033] T 基 —Base time, T for each term in the sequence 基 same;

[0034] T 分 —Decompose time, T for each term in the sequence. 分different;

[0035] Tmin—The master control time value is the master control time corresponding to the minimum allowable irradiation dose of all products in the cycle;

[0036] Tmax—The master control time value is the master control time corresponding to the maximum allowable irradiation dose of all products in the cycle;

[0037] Synchronization time T 同 When combining and sorting into an irradiation cycle, multiple variables are synchronized to the same time value T according to the general term principle of the sequence. 同 Determine the master control time value for this irradiation cycle, time value T. 同 This represents the actual master control time for all products in the loop;

[0038] Actual master control time T 实际 The common master time performed by all products within the same irradiation cycle is defined as the actual master time of the product within the cycle.

[0039] Wherein, the actual master control time T of the product 实际 The maximum allowable dose is greater than or equal to the minimum theoretical master control time in the irradiation cycle, and less than or equal to the minimum allowable dose corresponding to the maximum master control time in the cycle, ensuring that the absorbed dose of all products in the irradiation cycle is within the allowable dose range;

[0040] Constant value optimization: The master control time of representative products within the same period is used as the reference time, i.e., constant, for irradiation processing. Representative products meet the requirements of irradiation dose, incoming processing volume, and incoming balance stability.

[0041] Remainder Recycle: If the product master control time is greater than the reference time, and the remainder after deducting the reference time is greater than the step action time, then it will participate in the next master control time combination recycle after completing the first reference time.

[0042] Minimum constant: The minimum constant is an indivisible number, which is the stepping action time of the irradiation device, that is, the time it takes for the irradiation container to step from the current station to the next station. This time cannot be further divided, and the master control time is greater than or equal to the stepping action time.

[0043] First and last container change succession cycle: The number of irradiation containers in the irradiation cycle is greater than the number of stations of the irradiation device. When the first irradiation container of the cycle enters the first station of the irradiation chamber, the master control time is changed to the corresponding master control time on the control interface of the PLC controller to achieve the succession cycle and the continuous operation of the irradiation device.

[0044] Optimize dose inhomogeneity (DUR) and dose control rate (DCR): Calculate DUR and DCR using a weighted calculation formula.

[0045] To solve its technical problem, the further technical solution adopted by the method of the present invention is as follows:

[0046] Furthermore, in step S1, the theoretical master control time value for the processing of the media module is calculated according to formula c:

[0047]

[0048] In the formula:

[0049] r—redundancy coefficient, typically taken as 1.05;

[0050] ρ—Influence coefficient of different densities;

[0051] D min —Minimum permissible radiation dose;

[0052] T 主 —Master control time;

[0053] T 理论 —Theoretical master control time;

[0054] Furthermore, in step S2, the selection criteria satisfied by the representative media module include:

[0055] The number of representative media modules received is large;

[0056] The representative medium module allows for a moderate irradiation dose;

[0057] The representative media modules have a moderate loading density;

[0058] The quantity of representative media modules is balanced and continuous;

[0059] Reference time T of representative media module 基 Greater than the stepping action time T of the irradiation device 步 ;

[0060] Based on the selection criteria, the master control time T of the representative media module is determined. 主 This is the reference time for the operation control of the irradiation device during a specified period.

[0061] Furthermore, in step S10, the actual master control time of the product within the cycle is calculated using formula d:

[0062] T 实际 =T 基 +T 同 Formula d;

[0063] In the formula:

[0064] T 同 —Synchronize time;

[0065] T 基 —Base time;

[0066] T 实际 —Actual master control time.

[0067] Furthermore, in step S10, the actual master control time T of the product is expressed by the inequality e. 实际 Scope:

[0068] T min(大) ≤T 实际 ≤T max(小) Inequality e;

[0069] In the formula:

[0070] T min(大) —The maximum allowable value corresponding to the minimum theoretical master control time in an irradiation cycle;

[0071] T 实际 —Actual master control time of the product;

[0072] T max(小) —The minimum allowable value corresponding to the maximum master control time in the loop.

[0073] Furthermore, in step S10, the dose inhomogeneity (DUR) and dose control rate (DCR) are calculated using formulas f and g with weighted averages:

[0074] DUR=∑D max1…n / ∑D min1…n Formula f;

[0075] DCR=∑D 实际1…n / ∑D 理论1…n Formula g;

[0076] In the formula:

[0077] DUR—Dose nonuniformity;

[0078] DCR—Dose control rate;

[0079] D max1…n —All maximum dose values ​​actually absorbed by the product;

[0080] D min1…n —The minimum dose values ​​that the product is actually absorbed.

[0081] The beneficial effects of this invention are:

[0082] This invention provides a complete control system and usage method for dose control in gamma irradiation devices, offering theoretical and practical support for the operation and control of large-scale irradiation devices. It provides a stable, optimized, and operable scheme and method for dose control in irradiation processing, which can improve the dose control rate (DCR) by 2-7% and optimize the dose inhomogeneity (DUR) by 3-8%. This not only increases production capacity but also significantly enhances economic benefits, aligning with national low-carbon and energy-saving policies. The overall benefits are considerable, achieving optimized improvement in irradiation dose control rate and dose inhomogeneity, which in fact largely reflects the optimized improvement in energy utilization, irradiation production capacity, and economic benefits.

[0083] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, the preferred embodiments of the present invention are described in detail below with reference to the accompanying drawings. Attached Figure Description

[0084] Figure 1 The master control time T of the irradiation device described in this invention 主 surface;

[0085] Figure 2 This is a table showing the influence coefficient ρ of the absorbed dose of products with different densities in the irradiation device described in this invention;

[0086] Figure 3 This is the theoretical non-uniformity DUR table for the irradiation device described in this invention;

[0087] Figure 4 This is the irradiation combination sorting table of the irradiation device described in this invention;

[0088] Figure 5 This invention relates to the operating control parameters and calculation method of the irradiation device described in this invention. Detailed Implementation

[0089] The following specific embodiments illustrate the detailed implementation of the present invention. Those skilled in the art can easily understand the advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented in other different ways, that is, different modifications and changes can be made without departing from the scope disclosed in the present invention.

[0090] Example 1:

[0091] An irradiation dose control system includes a medium module, an irradiation container, a conveying device, a PLC controller, an irradiation device, and an irradiation chamber. The irradiation dose control system uses the conveying device to operate the medium module, which is located in the irradiation container. The irradiation device is located in the irradiation chamber. The irradiation container is conveyed in a full-load mode according to the PLC control program and action instructions. The conveying device transports the irradiation container to the irradiation chamber and receives gamma ray irradiation. The temperature in the irradiation chamber is controlled to be less than 90°C. The irradiation chamber is equipped with a temperature detector, a smoke detector, an audible and visual alarm device, and a safety interlock.

[0092] In Example 1, the conveying device uses a roller conveyor to operate the irradiation container and the medium module set inside the irradiation container in a double-layer, bidirectional, four-channel automatic layer-changing and surface-changing cargo cover source operation mode.

[0093] In Example 1, the irradiation mode of the irradiation container is as follows: from the first irradiation container entering the irradiation station of the irradiation chamber to the last irradiation container entering the irradiation station of the irradiation chamber, completing the irradiation process and leaving the irradiation station, which is one irradiation cycle.

[0094] In Example 1, the number of irradiation containers is greater than or equal to the number of workstations in an irradiation cycle.

[0095] In Example 1, the continuous operation mode of the irradiation device is as follows: the master control time of several irradiation containers that meet the general term formula of the sequence within the current period is arranged into a sequence to form an irradiation cycle. The irradiation device is controlled by the PLC controller to perform irradiation processing. After the irradiation processing is completed, the next irradiation cycle is continued.

[0096] Example 2:

[0097] An application method for an irradiation dose control system, the application method including the operation control parameters of the irradiation device and the method for calculating the value, and the combination and sorting principles and methods of the irradiation cycle of the medium module processing;

[0098] The operation control parameters and calculation method of the irradiation device include the following steps, such as... Figure 5 As shown:

[0099] S1: Calculate the theoretical master control time T for media module processing. 理论 The theoretical master control time value for the processing of the medium module is calculated according to the formula, which is the time for the irradiation container to move from one irradiation station to the next irradiation station by the PLC control program of the irradiation device plus the dwell time at the next irradiation station.

[0100] S2: Determine the reference time T 基 Select a representative medium module and its corresponding irradiation processing master control time T. 主As a reference time value, this representative media module meets the selection criteria;

[0101] Reference time T 基 Specifically, it refers to a time value that can be broken down and included in the theoretical master control time of most products processed by a certain irradiation device. Its significance is that this time value is used as a constant for the combination and sorting of irradiation cycles, and the products participating in this irradiation cycle are broken down and combined and sorted. In order to maximize the capacity of the irradiation device, the benchmark time is determined by selecting a representative product and using its corresponding irradiation processing master control time as the benchmark time value.

[0102] S3: Determine the decomposition time T 分 Before irradiation processing, in order to meet the needs of irradiation cycle grouping and sequencing, the theoretical master control time T of the dielectric module is calculated using formula a. 理论 Subtracting a baseline time yields the decomposition time T. 分 Decomposition time T 分 In a combined irradiation cycle sequencing, a uniform, shared operating control time parameter T is followed. 共 ;

[0103] T 分 =T 理论 -T 基 Formula a;

[0104] In the formula:

[0105] T 基 —Base time;

[0106] T 理论 —Theoretical master control time;

[0107] T 分 —Decomposition time;

[0108] S4: Execute the irradiation cycle: group several irradiation containers loaded with different media modules according to the same actual master control time. The cycle continues from the first irradiation container entering the irradiation station in the irradiation chamber to the last irradiation container completing the irradiation process and leaving the irradiation station in the irradiation chamber.

[0109] A single irradiation cycle consists of an irradiation cycle starter, several irradiation containers, and an irradiation cycle tailer, all operating under the same actual master control time.

[0110] Among them, the first irradiation container of an irradiation cycle is defined as the first irradiation container processed into an irradiation cycle according to the same decomposition master control time.

[0111] Irradiation cycle tail box: The last irradiation container processed into an irradiation cycle according to the same decomposition master control time is defined as the irradiation cycle tail box;

[0112] The combination and sorting principles and methods for the processing irradiation cycle of the medium module arrange the main control times of several products to be irradiated that conform to the general formula of the sequence into a sequence, forming an irradiation cycle. This cycle is then controlled by a PLC to perform irradiation processing. After this cycle is completed, the next irradiation cycle begins, achieving continuous operation of the irradiation device. This patent proposes five principles for compiling the combination and sorting sheet. In practical work, these principles must be correctly mastered and used, and the quality of the sheet must be continuously improved to enhance the dose control level. The steps include:

[0113] S10: Arrange the main control time of several products to be irradiated that conform to the general term formula of the sequence in the current period into a sequence to form an irradiation cycle. Then, control the irradiation device to perform irradiation processing through the PLC controller. After the cycle is completed, the next irradiation cycle is continued to realize the continuous operation of the irradiation device.

[0114] The general formula for the sequence follows this principle: an irradiation cycle has a master control time, the value of which lies between the master control time Tmin corresponding to the minimum allowable irradiation dose of all products in the cycle and the master control time Tmax corresponding to the maximum allowable irradiation dose, as shown in inequality b. In the sequence, the values ​​of each sub-term T... 主 Decompose into constant T 基 +Variable T 分 , deduct T 基 The remaining time value is defined as the decomposition time T. 分 T 分 ≥T 步 That is, the decomposition time is greater than or equal to the stepping action time of the irradiation device when scheduling orders;

[0115] Tmin≤T 基 +T 分 The inequality b ≤ Tmax;

[0116] In the formula:

[0117] T 基 —Base time, T for each term in the sequence 基 same;

[0118] T 分 —Decompose time, T for each term in the sequence. 分 different;

[0119] Tmin—The master control time value is the master control time corresponding to the minimum allowable irradiation dose of all products in the cycle;

[0120] Tmax—The master control time value is the master control time corresponding to the maximum allowable irradiation dose of all products in the cycle;

[0121] Synchronization time T同 When combining and sorting into an irradiation cycle, multiple variables are synchronized to the same time value T according to the general term principle of the sequence. 同 Determine the master control time value for this irradiation cycle, time value T. 同 This represents the actual master control time for all products in the loop;

[0122] Actual master control time T 实际 The common master time performed by all products within the same irradiation cycle is defined as the actual master time of the product within the cycle.

[0123] Wherein, the actual master control time T of the product 实际 The maximum allowable dose is greater than or equal to the minimum theoretical master control time in the irradiation cycle, and less than or equal to the minimum allowable dose corresponding to the maximum master control time in the cycle, ensuring that the absorbed dose of all products in the irradiation cycle is within the allowable dose range;

[0124] Constant value optimization: The master control time of representative products within the same period is used as the reference time, i.e., constant, for irradiation processing. Representative products meet the requirements of irradiation dose, incoming processing volume, and incoming balance stability.

[0125] Remainder Recycle: If the product master control time is greater than the reference time, and the remainder after deducting the reference time is greater than the step action time, then it will participate in the next master control time combination recycle after completing the first reference time.

[0126] Minimum constant: The minimum constant is an indivisible number, which is the stepping action time of the irradiation device, that is, the time it takes for the irradiation container to step from the current station to the next station. This time cannot be further divided, and the master control time is greater than or equal to the stepping action time.

[0127] First and last container change succession cycle: The number of irradiation containers in the irradiation cycle is greater than the number of stations of the irradiation device. When the first irradiation container of the cycle enters the first station of the irradiation chamber, the master control time is changed to the corresponding master control time on the control interface of the PLC controller to achieve the succession cycle and the continuous operation of the irradiation device.

[0128] In production practice, a current period irradiation production schedule and a daily / shift production schedule are typically prepared, such as... Figure 4 As shown, the irradiation cycle combination sequence sheet is used as a production plan instruction and issued to the shift operation control personnel. Based on the product information and corresponding master control time parameters, the equipment operation is controlled to achieve the expected irradiation of the products. Figure 4 This table lists the combination and sorting of PLC operating time control parameters for a specific irradiation cycle of a certain irradiation device. The master control time in the table is the actual master control time, which is a key parameter for irradiation dose control.

[0129] Optimize dose inhomogeneity (DUR) and dose control rate (DCR): Calculate DUR and DCR using a weighted calculation formula.

[0130] In Example 2, in step S1, the theoretical master control time value for the processing of the media module is calculated according to formula c:

[0131]

[0132] In the formula:

[0133] r—redundancy coefficient, typically taken as 1.05;

[0134] ρ—Influence coefficient of different densities;

[0135] D min —Minimum permissible radiation dose;

[0136] T 主 —Master control time;

[0137] T 理论 —Theoretical master control time;

[0138] Master control time T 主 Table: Master control schedule with elements corresponding to product loading density, irradiation date, and master control time, such as Figure 1 As shown, it provides the master control time that should be set for a certain irradiation device to absorb the minimum dose of 1 kGy when processing a product of a certain loading density on a certain date, under the condition of maintaining a certain initial cobalt source activity. The master control time is updated periodically based on the dose field test results and the cobalt source decay law. Figure 1 The dosage rates corresponding to different density products at a certain time are provided. Only the parameter mode and usage method are provided here. The acquisition and process of the data are not part of the content of this patent application and will not be described here.

[0139] Table of Influence Coefficients ρ for Different Densities: In a continuously operating irradiation production line, products of one density are irradiated sequentially with products of different densities. Density is a key factor in irradiated dose; the absorbed dose is inversely proportional to the product density. The sequential irradiation of products of different densities will affect each other's irradiated dose. Through dose field testing, the value of the mutual influence coefficient ρ of absorbed dose from products of different densities is obtained, as shown below. Figure 2 As shown, the usage mode and method of the mutual influence coefficient generated when products of different densities are irradiated are provided. The process of obtaining parameter data is not part of the content of this patent and will not be described here.

[0140] In Example 2, the selection criteria satisfied by the representative medium module in step S2 include:

[0141] The number of representative media modules received is large;

[0142] The representative medium module allows for a moderate irradiation dose;

[0143] The representative media modules have a moderate loading density;

[0144] The quantity of representative media modules is balanced and continuous;

[0145] Reference time T of representative media module 基 Greater than the stepping action time T of the irradiation device 步 ;

[0146] Based on the selection criteria, the master control time T of the representative media module is determined. 主 This is the reference time for the operation control of the irradiation device during a specified period.

[0147] In Example 2, in step S10, the actual master control time of the product within the cycle is calculated using formula d:

[0148] T 实际 =T 基 +T 同 Formula d;

[0149] In the formula:

[0150] T 同 —Synchronize time;

[0151] T 基 —Base time;

[0152] T 实际 —Actual master control time.

[0153] In Example 2, in step S10, the actual master control time T of the product is expressed by inequality e. 实际 Scope:

[0154] T min(大) ≤T 实际 ≤T max(小) Inequality e;

[0155] In the formula:

[0156] T min(大) —The maximum allowable value corresponding to the minimum theoretical master control time in an irradiation cycle;

[0157] T 实际 —Actual master control time of the product;

[0158] T max(小) —The minimum allowable value corresponding to the maximum master control time in the loop.

[0159] Theoretical Inhomogeneity (DUR) Table: Inhomogeneity represents the ratio of the maximum dose to the minimum dose, i.e., DUR = Dmax / Dmin. The smaller this value, the more uniform and stable the irradiation dose. Figure 3 As shown, the irradiated dose of a product or a product in an irradiation container in a dose field is a threshold value, with minimum and maximum dose values ​​and their distribution areas. The theoretical dose resonator (DUR) from dose field test results can be used to convert between the minimum and maximum dose values. Sometimes, it can be used to calculate the theoretical maximum absorbed dose to assess whether the theoretical master time of the product within the programmed irradiation cycle conforms to the maximum or minimum value of its permissible irradiated dose range. Figure 3 The application mode and method for DUR values ​​of irradiation dose non-uniformity corresponding to products with different loading densities are described here, but the data and acquisition process are not the content of this patent.

[0160] In Example 2, in step S10, the dose nonuniformity (DUR) and dose control rate (DCR) are calculated using formulas f and g with weighted averages:

[0161] DUR=∑D max1…n / ∑D min1…n Formula f;

[0162] DCR=∑D 实际1…n / ∑D 理论1…n Formula g;

[0163] In the formula:

[0164] DUR—Dose nonuniformity;

[0165] DCR—Dose control rate;

[0166] D max1…n —All maximum dose values ​​actually absorbed by the product;

[0167] D min1…n —The minimum dose values ​​that the product is actually absorbed.

[0168] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structure made using the content of the present invention specification and drawings, or directly or indirectly applied to other related technical fields, is similarly included within the patent protection scope of the present invention.

Claims

1. An application method for an irradiation dose control system, characterized in that: The application method includes the operation control parameters and value calculation methods of the irradiation device, and the combination and sorting principles and methods of the medium module processing irradiation cycle; The operation control parameters and calculation method of the irradiation device include the following steps: S1: Calculate the theoretical master control time T for media module processing. 理论 The theoretical master control time value for the processing of the medium module is calculated according to the formula, which is the time for the irradiation container to move from one irradiation station to the next irradiation station by the PLC control program of the irradiation device plus the dwell time at the next irradiation station. S2: Determine the reference time T 基 Select a representative medium module and its corresponding irradiation processing master control time T. 主 As a reference time value, this representative media module meets the selection criteria; S3: Determine the decomposition time T 分 Before irradiation processing, in order to meet the needs of irradiation cycle grouping and sequencing, the theoretical master control time T of the dielectric module is calculated using formula a. 理论 Subtracting a baseline time yields the decomposition time T. 分 Decomposition time T 分 In a combined irradiation cycle sequencing, a uniform, shared operating control time parameter T is followed. 共 ; T 分 =T 理论 -T 基 Formula a; In the formula: T 基 —Base time; T 理论 —Theoretical master control time; T 分 —Decomposition time; S4: Execute the irradiation cycle: group several irradiation containers loaded with different media modules according to the same actual master control time. The cycle continues from the first irradiation container entering the irradiation station in the irradiation chamber to the last irradiation container completing the irradiation process and leaving the irradiation station in the irradiation chamber. A single irradiation cycle consists of an irradiation cycle starter, several irradiation containers, and an irradiation cycle tailer, all operating under the same actual master control time. Among them, the first irradiation container of an irradiation cycle is defined as the first irradiation container processed into an irradiation cycle according to the same decomposition master control time. Irradiation cycle tail box: The last irradiation container processed into an irradiation cycle according to the same decomposition master control time is defined as the irradiation cycle tail box; The combination and sequencing principles and methods for the processing irradiation cycles of the medium module include the following steps: S10: Arrange the main control time of several products to be irradiated that conform to the general term formula of the sequence in the current period into a sequence to form an irradiation cycle. Then, control the irradiation device to perform irradiation processing through the PLC controller. After the cycle is completed, the next irradiation cycle is continued to realize the continuous operation of the irradiation device. The general formula for the sequence follows this principle: an irradiation cycle has a master control time, the value of which lies between the master control time Tmin corresponding to the minimum allowable irradiation dose of all products in the cycle and the master control time Tmax corresponding to the maximum allowable irradiation dose, as shown in inequality b. In the sequence, the values ​​of each sub-term T... 主 Decompose into constant T 基 +Variable T 分 , deduct T 基 The remaining time value is defined as the decomposition time T. 分 T 分 ≥T 步 That is, the decomposition time is greater than or equal to the stepping action time of the irradiation device when scheduling orders; Tmin≤T 基 +T 分 The inequality b ≤ Tmax; In the formula: T 基 —Base time, T for each term in the sequence 基 same; T 分 —Decompose time, T for each term in the sequence. 分 different; Tmin—The master control time value is the master control time corresponding to the minimum allowable irradiation dose of all products in the cycle; Tmax—The master control time value is the master control time corresponding to the maximum allowable irradiation dose of all products in the cycle; Synchronization time T 同 When combining and sorting into an irradiation cycle, multiple variables are synchronized to the same time value T according to the general term principle of the sequence. 同 Determine the master control time value for this irradiation cycle, time value T. 同 This represents the actual master control time for all products in the cycle; Actual master control time T 实际 The common master time performed by all products within the same irradiation cycle is defined as the actual master time of the product within the cycle. Wherein, the actual master control time T of the product 实际 The maximum allowable dose is greater than or equal to the minimum theoretical master control time in the irradiation cycle, and less than or equal to the minimum allowable dose corresponding to the maximum master control time in the cycle, ensuring that the absorbed dose of all products in the irradiation cycle is within the allowable dose range; Constant value optimization: The master control time of representative products within the same period is used as the reference time, i.e., constant, for irradiation processing. Representative products meet the requirements of irradiation dose, incoming processing volume, and incoming balance stability. Remainder Recycle: If the product master control time is greater than the reference time, and the remainder after deducting the reference time is greater than the step action time, then it will participate in the next master control time combination recycle after completing the first reference time. Minimum constant: The minimum constant is an indivisible number, which is the stepping action time of the irradiation device, that is, the time it takes for the irradiation container to step from the current station to the next station. This time cannot be further divided, and the master control time is greater than or equal to the stepping action time. First and last container change succession cycle: The number of irradiation containers in the irradiation cycle is greater than the number of stations of the irradiation device. When the first irradiation container of the cycle enters the first station of the irradiation chamber, the master control time is changed to the corresponding master control time on the control interface of the PLC controller to achieve the succession cycle and the continuous operation of the irradiation device. Optimize dose inhomogeneity (DUR) and dose control rate (DCR): Calculate DUR and DCR using a weighted calculation formula.

2. The application method for an irradiation dose control system according to claim 1, characterized in that: In step S1, the theoretical master control time value for the processing of the media module is calculated according to formula c: In the formula: r—redundancy coefficient, typically taken as 1.05; ρ—Influence coefficient of different densities; D min —Minimum permissible radiation dose; T 主 —Master control time; T 理论 —Theoretical master control time.

3. The application method for an irradiation dose control system according to claim 1, characterized in that: In step S2, the selection criteria satisfied by the representative media module include: The number of representative media modules received is large; The representative medium module allows for a moderate irradiation dose; The representative media module has a moderate loading density; The quantity of representative media modules is balanced and continuous; Reference time T of representative media module 基 Greater than the stepping action time T of the irradiation device 步 ; Based on the selection principle, the master control time T of the representative medium module is determined as the reference time for the operation control of the irradiation device within a specified period.

4. The application method for an irradiation dose control system according to claim 1, characterized in that: In step S10, the actual master control time of the product within the cycle is calculated using formula d: T 实际 =T 基 +T 同 Formula d; In the formula: T 同 —Synchronize time; T 基 —Base time; T 实际 —Actual master control time.

5. The application method for an irradiation dose control system according to claim 1, characterized in that: In step S10, the actual master control time T of the product is expressed by the inequality e. 实际 Scope: T min(大) ≤T 实际 ≤T max(小) Inequality e; In the formula: T min(大) —The maximum allowable value corresponding to the minimum theoretical master control time in an irradiation cycle; T 实际 —Actual master control time of the product; T max(小) —The minimum allowable value corresponding to the maximum master control time in the loop.

6. The application method for an irradiation dose control system according to claim 1, characterized in that: The irradiation dose control system includes a medium module, an irradiation container, a conveying device, a PLC controller, an irradiation device, and an irradiation chamber. The irradiation dose control system uses the conveying device to operate the medium module, which is located in the irradiation container. The irradiation device is located in the irradiation chamber. The irradiation container is conveyed in a full-load mode according to the PLC control program and action instructions. The conveying device transports the irradiation container to the irradiation chamber and receives gamma ray irradiation. The temperature in the irradiation chamber is controlled to be less than 90°C. The irradiation chamber is equipped with a temperature detector, a smoke detector, an audible and visual alarm device, and a safety interlock. The conveying device uses a roller conveyor system with double-layer, bidirectional, four-channel automatic layer-changing and surface-changing cargo cover source operation mode to operate the irradiation container and the medium module set in the irradiation container.

7. The application method for an irradiation dose control system according to claim 6, characterized in that: The irradiation mode of the irradiation container is as follows: from the moment the first irradiation container enters the irradiation station of the irradiation chamber to the moment the last irradiation container enters the irradiation station of the irradiation chamber, completes the irradiation process, and leaves the irradiation station, this constitutes one irradiation cycle.

8. The application method for an irradiation dose control system according to claim 7, characterized in that: In one irradiation cycle, the number of irradiation containers is greater than or equal to the number of workstations in the irradiation chamber.

9. The application method for an irradiation dose control system according to claim 7, characterized in that: The continuous operation mode of the irradiation device is as follows: the master control time of several irradiation containers that meet the general term formula of the sequence within the current period is arranged into a sequence to form an irradiation cycle. The irradiation device is controlled by the PLC controller to perform irradiation processing. After the irradiation processing is completed, the next irradiation cycle is continued.

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