CN117261254A - Electric melting control device and control method - Google Patents
Electric melting control device and control method Download PDFInfo
- Publication number
- CN117261254A CN117261254A CN202311478478.0A CN202311478478A CN117261254A CN 117261254 A CN117261254 A CN 117261254A CN 202311478478 A CN202311478478 A CN 202311478478A CN 117261254 A CN117261254 A CN 117261254A
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- current
- direct current
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- 238000002844 melting Methods 0.000 title claims abstract description 18
- 230000008018 melting Effects 0.000 title claims abstract description 18
- 238000000034 method Methods 0.000 title claims abstract description 12
- 238000010438 heat treatment Methods 0.000 claims abstract description 20
- 238000001514 detection method Methods 0.000 claims abstract description 17
- 230000002093 peripheral effect Effects 0.000 claims abstract description 17
- 238000003466 welding Methods 0.000 claims abstract description 17
- 239000012943 hotmelt Substances 0.000 claims abstract description 16
- 238000005485 electric heating Methods 0.000 claims description 14
- 230000001276 controlling effect Effects 0.000 claims description 10
- 238000004891 communication Methods 0.000 claims description 6
- 230000001105 regulatory effect Effects 0.000 claims description 4
- 101100424891 Bacteroides fragilis tetX gene Proteins 0.000 claims description 3
- 230000006641 stabilisation Effects 0.000 claims description 3
- 238000011105 stabilization Methods 0.000 claims description 3
- 230000007704 transition Effects 0.000 claims description 3
- 239000003990 capacitor Substances 0.000 claims description 2
- 238000005259 measurement Methods 0.000 abstract description 4
- 239000004698 Polyethylene Substances 0.000 description 9
- 239000010410 layer Substances 0.000 description 7
- 238000010586 diagram Methods 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000005611 electricity Effects 0.000 description 1
- 230000004927 fusion Effects 0.000 description 1
- 230000020169 heat generation Effects 0.000 description 1
- 239000011229 interlayer Substances 0.000 description 1
- -1 polyethylene Polymers 0.000 description 1
- 229920000573 polyethylene Polymers 0.000 description 1
- 238000005070 sampling Methods 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C65/00—Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor
- B29C65/02—Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor by heating, with or without pressure
- B29C65/18—Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor by heating, with or without pressure using heated tools
- B29C65/22—Heated wire resistive ribbon, resistive band or resistive strip
- B29C65/221—Heated wire resistive ribbon, resistive band or resistive strip characterised by the type of heated wire, resistive ribbon, band or strip
- B29C65/224—Heated wire resistive ribbon, resistive band or resistive strip characterised by the type of heated wire, resistive ribbon, band or strip being a resistive ribbon, a resistive band or a resistive strip
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C37/00—Component parts, details, accessories or auxiliary operations, not covered by group B29C33/00 or B29C35/00
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C66/00—General aspects of processes or apparatus for joining preformed parts
- B29C66/90—Measuring or controlling the joining process
- B29C66/91—Measuring or controlling the joining process by measuring or controlling the temperature, the heat or the thermal flux
- B29C66/914—Measuring or controlling the joining process by measuring or controlling the temperature, the heat or the thermal flux by controlling or regulating the temperature, the heat or the thermal flux
- B29C66/9141—Measuring or controlling the joining process by measuring or controlling the temperature, the heat or the thermal flux by controlling or regulating the temperature, the heat or the thermal flux by controlling or regulating the temperature
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C37/00—Component parts, details, accessories or auxiliary operations, not covered by group B29C33/00 or B29C35/00
- B29C2037/90—Measuring, controlling or regulating
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Control Of Resistance Heating (AREA)
Abstract
The invention discloses an electric melting control device and a control method, wherein the control device comprises the following components: the intelligent control and peripheral detection circuit is used for controlling the hot melt network power supply module to work according to detected signals. According to the invention, the real-time temperature of the resistance wire mesh is calculated by measuring the resistance of the heating wire mesh (resistive load) and the temperature resistance coefficient, so that the measurement is accurate, the time delay is avoided, the welding temperature can be controlled better, and the welding quality is improved.
Description
Technical Field
The invention relates to the technical field of electric heating welding equipment, in particular to an electric heating welding control device and a control method.
Background
The intelligent electric heating welding equipment is mainly used for welding joints between heat-insulating pipelines, hot melting sleeves are used for lap joint at two ends of the heat-insulating pipelines, and a sealed cavity is formed at the joint position of the pipelines through welding two layers of PE (polyethylene) at the lap joint part. And the overlapped two layers of PE are welded by adopting a resistance type electric heating net, the resistance type electric heating net is placed between the two layers of PE, then the two layers of PE are pressed, the resistance type electric heating net is electrified to generate heat, the PE of the interlayer is melted, and the fusion between the two layers of PE is achieved.
The existing intelligent electric heating welding equipment forms feedback control output current by detecting the temperature of a heating object. The temperature measuring resistor is placed between two layers of PE at the lap joint, the temperature returned by the temperature measuring mode can have different measured values at different positions of the pipeline, the local temperature of the position of the temperature measuring element is reflected, and the temperature sampling value deviates from the actual temperature. The two layers of PE at the lap joint are electrically heated and welded, and tightening force is required to be applied during heating to achieve the purpose of hot melt connection, but the temperature measuring element is easy to damage during tightening.
Disclosure of Invention
The invention aims to solve the technical problem of providing an electric heating melting control device which can better control the melting temperature and improve the melting quality.
In order to solve the technical problems, the invention adopts the following technical scheme: an electric melting control device characterized by comprising: the intelligent control and peripheral detection circuit is used for controlling the hot melt network power supply module to work according to detected signals.
The further technical proposal is that: the hot melt network power supply module comprises a rectification module, a direct current pulse module and a voltage reduction and stabilization module, wherein the signal input end of the rectification module is used for inputting alternating current, and the rectification module is used for rectifying the input three-phase or single-phase alternating current to obtain high-voltage direct current; the output end of the rectifying module is connected with the input end of the direct current pulse module, the direct current pulse module is controlled by the intelligent control and peripheral detection circuit, the direct current input into the direct current pulse module passes through the IGBT loop, and the intelligent control and peripheral detection circuit controls the Gate end of the IGBT to output pulse direct current with variable frequency and pulse width; the output end of the direct current pulse module is connected with the input end of the voltage-reducing and voltage-stabilizing module, the output end of the voltage-reducing and voltage-stabilizing module is connected with the resistive load, the pulse direct current is reduced and stabilized through the LC circuit and is loaded on the resistive load, the output end collects voltage and current and is used as a feedback signal, PWM is regulated according to the feedback signal, and the purpose of controlling heating current is achieved.
The further technical proposal is that: the hot melt network power supply module comprises a rectifier bridge, wherein an input end of the rectifier bridge is input with alternating current, one output end of the rectifier bridge is connected with a zero line, the other output end of the rectifier bridge is connected with a collector electrode of an IGBT tube Q1, a gate electrode of the IGBT tube Q1 is connected with a control signal output end of an intelligent control and peripheral detection circuit, an emitter electrode of the IGBT tube Q1 is connected with one end of an inductor L1, the other end of the inductor L1 is divided into three paths, the first path is grounded through a capacitor C1, the second path is connected with a voltage sensor, and the third path is grounded through a current sensor and a resistive load in sequence.
The further technical proposal is that: the intelligent control and peripheral detection circuit comprises a central processor module, wherein the central processor module is connected with a control end of an IGBT tube through an IGBT driving plate, a current and voltage acquisition module is used for acquiring current and voltage information of a direct current pulse module, a signal output end of the current and voltage acquisition module is connected with an acquisition signal input end of the central processor module, a signal of the central processor module is bidirectionally connected with a communication module, the communication module is connected with a cloud server through a 4G/5G network, and a positioning module is connected with a signal input end of the central processor module and used for positioning the device; the environment temperature sensor is connected with the signal input end of the central processing unit module and used for collecting the temperature information of the environment.
The invention also discloses an electric melting control method, which uses the electric melting control device, and comprises the following steps:
collecting the ambient temperature, loading a fixed current on the resistive load, and measuring the feedback voltage to obtain the resistance value of the resistive load and obtain the corresponding relation between the initial value temperature and the resistance;
calculating the resistance value R2 of the resistive load at the temperature of T2 according to the resistance-temperature coefficient TCR;
the output current is controlled, the voltage value is measured back, ri=Ui/Ii is calculated, ri and R2 are compared, the output current is continuously adjusted, ri and R2 are equal, and therefore the control temperature reaches T2.
A further technical solution is that the Temperature Coefficient of Resistance (TCR) represents the relative change of the resistance value when the temperature is changed by 1 degree celsius;
resistance value at a specific temperature:
R＝R 0 [1+TCR*(T-T 0 )]；
R 0 is the resistance value (Ω) at the reference temperature;
T 0 to determine R 0 Reference temperature (DEG C);
TCR is the temperature coefficient of resistance;
t is the temperature (DEG C) at which R is determined;
according to the above formula, the temperature of the transition calculates the formula:
R T the resistance value is the resistance value at a specific temperature;
according to the above formula, the TCR calculation formula:
the beneficial effects of adopting above-mentioned technical scheme to produce lie in: according to the invention, the real-time temperature of the resistance wire mesh is calculated by measuring the resistance of the heating wire mesh (resistive load) and the temperature resistance coefficient, so that the measurement is accurate, the time delay is avoided, the welding temperature can be controlled better, and the welding quality is improved.
Drawings
The invention will be described in further detail with reference to the drawings and the detailed description.
FIG. 1 is a schematic circuit diagram of a hot melt network power module in an apparatus according to an embodiment of the present invention;
FIG. 2 is a schematic block diagram of an apparatus according to an embodiment of the present invention;
fig. 3 is a flow chart of a method according to an embodiment of the invention.
Detailed Description
The following description of the embodiments of the present invention will be made clearly and fully with reference to the accompanying drawings, in which it is evident that the embodiments described are only some, but not all embodiments of the invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention, but the present invention may be practiced in other ways other than those described herein, and persons skilled in the art will readily appreciate that the present invention is not limited to the specific embodiments disclosed below.
As shown in fig. 1-2, an embodiment of the present invention discloses an electrothermal welding control apparatus, including: the intelligent control and peripheral detection circuit is used for controlling the hot melt network power supply module to work according to detected signals.
The hot melt network power supply module comprises a rectification module, a direct current pulse module and a voltage reduction and stabilization module, wherein the signal input end of the rectification module is used for inputting alternating current, and the rectification module is used for rectifying the input three-phase or single-phase alternating current to obtain high-voltage direct current; the output end of the rectifying module is connected with the input end of the direct current pulse module, the direct current pulse module is controlled by the intelligent control and peripheral detection circuit, the direct current input into the direct current pulse module passes through the IGBT loop, and the intelligent control and peripheral detection circuit controls the Gate end of the IGBT to output pulse direct current with variable frequency and pulse width; the output end of the direct current pulse module is connected with the input end of the voltage-reducing and voltage-stabilizing module, the output end of the voltage-reducing and voltage-stabilizing module is connected with the resistive load, the pulse direct current is reduced and stabilized through the LC circuit and is loaded on the resistive load, the output end collects voltage and current and is used as a feedback signal, PWM is regulated according to the feedback signal, and the purpose of controlling heating current is achieved.
The control object of the device is a pure resistive load, and the resistive load is characterized in that the current flowing through the resistive load exceeds a certain limit value, the resistive load can generate heat, and the larger the current is, the larger the heat generation amount is, and the higher the temperature is. By controlling the current (voltage) flowing through the resistive load, the amount of heat generated by the load can be controlled, and the heating target can be heated by the heat generated by the resistive load.
The device main hardware loop: 1. rectifying input three-phase or single-phase electricity to obtain high-voltage direct current; 2. the direct current passes through an IGBT loop, and the drive board controls the Gate end of the IGBT to output pulse direct current with variable frequency and pulse width; 3. the pulse direct current is reduced and stabilized through an LC loop, is loaded on a resistive load, and the output end collects voltage and current and is used as a feedback signal, PWM is regulated according to the feedback signal, and the purpose of controlling heating current is achieved
As shown in fig. 1, the hot melt network power supply module includes a rectifier bridge, the input of rectifier bridge inputs alternating current, an output termination zero line of rectifier bridge, another output termination of rectifier bridge is connected with the collector of IGBT pipe Q1, IGBT pipe Q1's gate with intelligent control and peripheral detection circuit's control signal output is connected, IGBT pipe Q1's projecting pole is connected with inductance L1's one end, inductance L1's the other end divide into three routes, and first way is connected with voltage sensor through electric capacity C1 ground, the second way is connected with, and the third is in proper order through current sensor and resistive load ground.
Further, as shown in fig. 2, the intelligent control and peripheral detection circuit comprises a central processor module, the central processor module is connected with the control end of the IGBT tube through the IGBT driving board, the current and voltage acquisition module is used for acquiring the current and voltage information of the direct current pulse module, the signal output end of the current and voltage acquisition module is connected with the acquisition signal input end of the central processor module, the signal of the central processor module is connected with the communication module in two directions, the communication module is connected with the cloud server through the 4G/5G network, and the positioning module is connected with the signal input end of the central processor module for positioning the device; the environment temperature sensor is connected with the signal input end of the central processing unit module and used for collecting the temperature information of the environment.
Intelligent control and peripheral detection circuit: the central processing unit is connected with the IGBT control loop, outputs PWM signals, controls the on and off of the IGBT, and outputs pulse level through the switch of IGBT. The operation and data display of the equipment are connected with the central controller through the HMI and the button, and the current, voltage and temperature acquisition module is connected with the IO port of the central controller.
Correspondingly, as shown in fig. 3, the embodiment of the invention also discloses an electric melting control method, which uses the electric melting control device and comprises the following steps:
collecting the ambient temperature, loading a fixed current on the resistive load, and measuring the feedback voltage to obtain the resistance value of the resistive load and obtain the corresponding relation between the initial value temperature and the resistance;
calculating the resistance value R2 of the resistive load at the temperature of T2 according to the resistance-temperature coefficient TCR;
the output current is controlled, the voltage value is measured back, ri=Ui/Ii is calculated, ri and R2 are compared, the output current is continuously adjusted, ri and R2 are equal, and therefore the control temperature reaches T2.
When the equipment is started each time, the voltage and current sensors are automatically zeroed on line, so that the accuracy of resistance measurement is improved;
judging the specification type of the repaired mouth, such as the repaired mouth with DN300 and DN1500 pipe diameters, corresponding to different resistance values, and automatically reading corresponding welding parameters of the modified type, such as parameters of heating current, temperature, time, resistance temperature coefficient and the like;
automatically measuring the temperature resistivity of the heating material, measuring a heating temperature curve through a temperature sensor, and calculating and storing the temperature resistivity of the heating material by combining the resistance change curve;
the welding temperature set by a user is converted into a resistance value according to the temperature resistance coefficient of the heating net wire, and the accurate control of the hot melting temperature is realized by controlling the resistance value of the heating net wire;
according to the temperature change rate of the electrothermal net wire in unit time, automatically adjusting the heating current;
heating to a preheating temperature (which can be set by a user), and automatically judging whether the electric heating mesh wire is tightly attached to the hot melting sleeve or not according to the temperature change rate and the current of the electric heating mesh wire, and starting automatic welding after the electric heating mesh wire is tightly attached;
the temperature coefficient of resistance (temperature coefficient of resistance, TCR) represents the relative change in resistance when the temperature is changed by 1 degree celsius.
Resistance value at a specific temperature:
R＝R 0 [1+TCR*(T-T 0 )]；
R 0 is the resistance value (Ω) at the reference temperature;
T 0 to determine R 0 Reference temperature (DEG C);
TCR is the temperature coefficient of resistance;
t is the temperature (DEG C) at which R is determined;
according to the above formula, the temperature of the transition calculates the formula:
R T the resistance value is the resistance value at a specific temperature;
according to the above formula, the TCR calculation formula:
according to the invention, the real-time temperature of the resistance wire mesh is calculated by measuring the resistance of the heating wire mesh (resistive load) and the temperature resistance coefficient, so that the measurement is accurate, the time delay is avoided, the welding temperature can be controlled better, and the welding quality is improved.
Claims (9)
1. An electric melting control device characterized by comprising: the intelligent control and peripheral detection circuit is used for controlling the hot melt network power supply module to work according to detected signals.
2. The electric fuse control apparatus of claim 1, wherein: the hot melt network power supply module comprises a rectification module, a direct current pulse module and a voltage reduction and stabilization module, wherein the signal input end of the rectification module is used for inputting alternating current, and the rectification module is used for rectifying the input three-phase or single-phase alternating current to obtain high-voltage direct current; the output end of the rectifying module is connected with the input end of the direct current pulse module, the direct current pulse module is controlled by the intelligent control and peripheral detection circuit, the direct current input into the direct current pulse module passes through the IGBT loop, and the intelligent control and peripheral detection circuit controls the Gate end of the IGBT to output pulse direct current with variable frequency and pulse width; the output end of the direct current pulse module is connected with the input end of the voltage-reducing and voltage-stabilizing module, the output end of the voltage-reducing and voltage-stabilizing module is connected with the resistive load, the pulse direct current is reduced and stabilized through the LC circuit and is loaded on the resistive load, the output end collects voltage and current and is used as a feedback signal, PWM is regulated according to the feedback signal, and the purpose of controlling heating current is achieved.
3. The electric fuse control apparatus of claim 2, wherein: the hot melt network power supply module comprises a rectifier bridge, wherein an input end of the rectifier bridge is input with alternating current, one output end of the rectifier bridge is connected with a zero line, the other output end of the rectifier bridge is connected with a collector electrode of an IGBT tube Q1, a gate electrode of the IGBT tube Q1 is connected with a control signal output end of an intelligent control and peripheral detection circuit, an emitter electrode of the IGBT tube Q1 is connected with one end of an inductor L1, the other end of the inductor L1 is divided into three paths, the first path is grounded through a capacitor C1, the second path is connected with a voltage sensor, and the third path is grounded through a current sensor and a resistive load in sequence.
4. The electric fuse control apparatus of claim 1, wherein: the intelligent control and peripheral detection circuit comprises a central processor module, wherein the central processor module is connected with a control end of an IGBT tube through an IGBT driving plate, a current and voltage acquisition module is used for acquiring current and voltage information of a direct current pulse module, a signal output end of the current and voltage acquisition module is connected with an acquisition signal input end of the central processor module, a signal of the central processor module is bidirectionally connected with a communication module, the communication module is connected with a cloud server through a 4G/5G network, and a positioning module is connected with a signal input end of the central processor module and used for positioning the device; the environment temperature sensor is connected with the signal input end of the central processing unit module and used for collecting the temperature information of the environment.
5. A method of controlling electric melting using the electric melting control apparatus according to any one of claims 1 to 4, characterized by comprising the steps of:
collecting the ambient temperature, loading a fixed current on the resistive load, and measuring the feedback voltage to obtain the resistance value of the resistive load and obtain the corresponding relation between the initial value temperature and the resistance;
calculating the resistance value R2 of the resistive load at the temperature of T2 according to the resistance-temperature coefficient TCR;
the output current is controlled, the voltage value is measured back, ri=Ui/Ii is calculated, ri and R2 are compared, the output current is continuously adjusted, ri and R2 are equal, and therefore the control temperature reaches T2.
6. The electric hot melt control method of claim 5, wherein: when the device is started each time, the voltage sensor and the current sensor are automatically zeroed on line.
7. The electric hot melt control method of claim 5, wherein: and according to the temperature change rate of the electrothermal net wire in unit time, automatically adjusting the heating current.
8. The electric hot melt control method of claim 5, wherein: heating to a preheating temperature, and automatically judging whether the electric heating mesh wire is tightly attached to the hot melting sleeve or not according to the temperature change rate and the current of the electric heating mesh wire, and starting automatic welding after the electric heating mesh wire is tightly attached.
9. The electric hot melt control method of claim 5, wherein: temperature Coefficient of Resistance (TCR) represents the relative change in resistance when the temperature changes by 1 degree celsius;
resistance value at a specific temperature:
R＝R 0 [1+TCR*(T-T 0 )]；
R 0 is the resistance value (Ω) at the reference temperature;
T 0 to determine R 0 Reference temperature (DEG C);
TCR is the temperature coefficient of resistance;
t is the temperature (DEG C) at which R is determined;
according to the above formula, the temperature of the transition calculates the formula:
R T the resistance value is the resistance value at a specific temperature;
according to the above formula, the TCR calculation formula:
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2023114725157 | 2023-11-07 | ||
| CN202311472515 | 2023-11-07 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN117261254A true CN117261254A (en) | 2023-12-22 |
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ID=89214495
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202311478478.0A Pending CN117261254A (en) | 2023-11-07 | 2023-11-08 | Electric melting control device and control method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN117261254A (en) |
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2023
- 2023-11-08 CN CN202311478478.0A patent/CN117261254A/en active Pending
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