LNG ship corrugated plate automatic welding equipment control system and control method thereof

Abstract

An LNG ship corrugated plate automatic welding equipment control system comprises a welding system, a motion execution mechanism, a control system and a sensing system, the control system comprises a PLC industrial personal computer, a coupler and a communication module, the PLC industrial personal computer is connected with the communication module through the coupler, a remote controller is connected with the communication module, and the sensing system is connected with the PLC industrial personal computer. The motion executing mechanism comprises a speed reducer, a servo motor and a servo controller, the sensing system comprises a first point laser sensor, a second point laser sensor, a tilt angle sensor, a contact type displacement sensor and a proximity sensor, and the welding system comprises a transformer, a water cooling machine and a welding power source. Based on the rapid, accurate and multi-directional sensing capability of a sensing system, collected data signals are transmitted to an industrial personal computer, the industrial personal computer processes related data and transmits control signals to a welding system and a motion execution mechanism in real time, corresponding technological parameters and mechanism actions are monitored and automatically adjusted through a sensor in the ripple crossing process, manual intervention is reduced, and the production efficiency is improved. And full-automatic welding of the corrugated plate is realized.

Description

Technical Field

[0001] The present invention relates to the technical field of ship welding, and in particular to a control system and a control method for automatic welding equipment of corrugated plates of an LNG ship. Background Art

[0002] The Mark III liquid cargo containment system is one of the mainstream forms of liquid cargo tanks of LNG ships. The corrugated plates used in its main shielding layer are made of 304L low-temperature stainless steel. The plate thickness is mostly 1.2 mm. They are stamped into cross-corrugated pleated plates, which are composed of corrugated sections and straight sections. The corrugated sections are divided into large and small sizes. The corrugated plates are shouldered and need to be welded by lap welding. Due to the huge size of the liquid cargo containment system, a large number of corrugated plates are used, and the welding process is difficult. The use of manual welding requires a lot of time for related training, and the welding efficiency is not high, the welding quality is low, and the cost is high.

[0003] The automation rate of the corrugated plate welding equipment currently in use is not high. Workers need to manually control the welding of the corrugated section. The operation threshold is high and the maintenance is difficult. The equipment motor and mechanical structure cannot be adjusted in time, which easily leads to operational errors and rework, resulting in huge use costs.

[0004] Therefore, in order to solve the above technical problems, a new Mark III LNG ship corrugated plate automatic welding equipment control system is provided to improve the equipment automation rate and reduce the equipment quality control cost and manual training cost. Summary of the invention

[0005] The object of the present invention is to provide a control system and a control method for automatic welding equipment of corrugated plates of LNG ships.

[0006] In order to achieve the above object, the technical solution of the present invention is: A control system for automatic welding equipment of corrugated plates of LNG ships, characterized in that it includes a welding system, a motion actuator, a control system and a sensor system. The control system includes a PLC industrial computer, a coupler and a communication module. The PLC industrial computer is electrically connected to the communication module through the coupler. The motion actuator includes a reducer, a servo motor and a servo controller, wherein the servo controller is electrically connected to the servo motor, and the servo controller is electrically connected to the communication module. The sensing system includes a first point laser sensor, a second point laser sensor, an inclination sensor, a contact displacement sensor and a proximity sensor, wherein the first point laser sensor, the second point laser sensor, the contact displacement sensor and the proximity sensor are all electrically connected to the communication module, the first point laser sensor is arranged at the front end of the motion actuator in the motion direction, the second point laser sensor is arranged between the first point laser sensor and the motion actuator, the contact displacement sensor includes a sensor head and a tail amplifier, and the inclination sensor is arranged on the motion actuator. The welding system comprises a transformer, a water cooler and a welding power source, and the welding power source is electrically connected to the communication module.

[0007] Furthermore, the servo motor includes an X-axis servo motor, a Y-axis servo motor, a Z-axis servo motor, an S-axis servo motor, and an R-axis servo motor.

[0008] Furthermore, the communication module includes an analog signal input and output module and a digital signal input and output module.

[0009] Furthermore, the control system also includes a touch screen and a remote controller, and both the touch screen and the remote controller are electrically connected to the PLC industrial computer.

[0010] The control method of the automatic welding equipment control system for the LNG ship corrugated plate is characterized in that when the sensor head at the top of the contact displacement sensor contacts the corrugated plate, the corrugation and the plane are judged by the height change and used as the error tracking, and the starting position of the corrugation is distinguished by the height change of the front and rear points; The first point laser sensor measures the distance between the first point laser sensor and the corrugated plate in real time, and senses the corrugated structure in the direction of equipment movement. When the first point laser sensor measures the corrugated structure, the PLC industrial computer transmits a control signal to the motion actuator according to the identified corrugated features, and executes preset action instructions such as crossing the corrugations; The second laser sensor swings left and right, sampling at a period of 50ms and an interval of 2ms, and collects the distance between the second laser sensor and the corrugated plate in real time. Based on the height difference of 1.2mm at the lap weld of the corrugated plate, the PLC industrial computer performs digital-to-analog conversion on the collected data, sets the parameter judgment conditions, and sends a control signal to the motion actuator when the midpoint deviates from the weld. The motion actuator adjusts the motion direction according to the signal; The inclination sensor monitors the equipment position and the state of crossing the ripples in real time, and transmits the collected mechanism inclination information to the PLC industrial computer in real time. After calculation, the industrial computer sends control instructions to the motion actuator to adjust the equipment posture in real time.

[0011] The present invention is based on the fast, accurate and multi-directional perception ability of the sensing system, and transmits the collected data signals to the industrial computer, which processes the relevant data and transmits the control signals to the welding system and motion actuator in real time. During the process of crossing the corrugations, the sensor monitors and automatically adjusts the corresponding process parameters and mechanism actions, reducing the required manual intervention and realizing fully automatic welding of corrugated plates. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a system structure block diagram of the present invention.

[0013] Reference numerals: 1. Control system, 101 PLC industrial computer, 102 touch screen, 103 remote control, 104 coupler, 105 communication module, 2Sensor system, 201 first point laser sensor, 202 second point laser sensor, 203 tilt sensor, 204 contact displacement sensor, 205 proximity sensor, 3. Welding system, 301 transformer, 302 water cooler, 303 welding power supply, 4. Motion actuators, 401 reducer, 402 servo motor, 403 servo controller. DETAILED DESCRIPTION

[0014] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0015] The present invention discloses a control system 1 for automatic welding equipment of corrugated plates of LNG ships, such as Figure 1 As shown, it includes a welding system 3, a motion actuator 4, a control system 1 and a sensor system 2. The control system 1 is electrically connected to the welding system 3, the motion actuator 4 and the sensor system 2 respectively. During operation, the control system 1 transmits a start signal to first start the motion control mechanism and the sensor system 2, and then receives the sensor information transmitted by the sensor system 2. After the sensor information is processed, the production control signal is transmitted to the motion actuator 4 and the welding system 3, and finally the motion control and welding control are performed.

[0016] like Figure 1As shown, the control system 1 includes a PLC industrial computer 101, a touch screen 102, a remote controller 103, a coupler 104 and a communication module 105. The touch screen 102 is electrically connected to the PLC industrial computer 101, the PLC industrial computer 101 is electrically connected to the communication module 105 through the coupler 104, the remote controller 103 is electrically connected to the communication module 105, the industrial computer is a Codesys PLC system, the coupler 104 is an Ethercat coupler 104, and the communication module 105 includes an analog signal input and output module and a digital signal input and output module, and has a digital-to-analog conversion function.

[0017] The motion actuator 4 includes a reducer 401, a servo motor 402 and a servo controller 403. The servo controller 403 is electrically connected to the servo motor 402. The servo controller 403 is electrically connected to the communication module 105. The servo motor 402 includes an X-axis servo motor 402, a Y-axis servo motor 402, a Z-axis servo motor 402, an S-axis servo motor 402 and an R-axis servo motor 402.

[0018] The sensing system 2 includes a first point laser sensor 201 , a second point laser sensor 202 , an inclination sensor 203 , a contact displacement sensor 204 and a proximity sensor 205 , and the first point laser sensor 201 , the second point laser sensor 202 , the contact displacement sensor 204 and the proximity sensor 205 are all electrically connected to the communication module 105 .

[0019] The welding system 3 includes a transformer 301 , a water cooler 302 and a welding power source 303 , and the welding power source 303 is electrically connected to the communication module 105 .

[0020] The control method using the LNG ship corrugated plate automatic welding equipment control system 1 comprises the following steps: The contact displacement sensor 204 includes a sensor head and a tail amplifier. When the sensor head at the top of the contact displacement sensor 204 contacts the corrugated plate, the corrugations and the plane are judged by the height change and used as error tracking. The starting position of the corrugations is distinguished by the height change between the front and rear points.

[0021] The first point laser sensor 201 is arranged at the front end of the motion actuator 4 in the motion direction. The first point laser sensor 201 measures the distance between the point laser sensor and the corrugated plate in real time, and senses the corrugated structure in the motion direction of the equipment. When the first point laser sensor 201 measures the corrugated structure, the PLC industrial computer 101 transmits a control signal to the motion actuator 4 according to the identified corrugated features, and executes preset action instructions such as climbing over the corrugations; The second point laser sensor 202 is arranged between the first point laser sensor 201 and the motion actuator 4. The second point laser sensor 202 swings left and right, and samples with a period of 50ms and an interval of 2ms. The distance between the second point laser sensor 202 and the corrugated plate is collected in real time. Based on the height difference of 1.2mm at the lap weld of the corrugated plate, the PLC industrial computer 101 performs digital-to-analog conversion on the collected data, sets the parameter judgment conditions, and sends a control signal to the motion actuator 4 when the midpoint deviates from the weld. The motion actuator 4 adjusts the movement direction according to the signal.

[0022] The inclination sensor 203 is arranged on the motion actuator 4. The inclination sensor 203 monitors the equipment position and the state of crossing the corrugation in real time, and transmits the collected mechanism inclination information to the PLC industrial computer 101 in real time. After calculation, the industrial computer sends a control instruction to the motion actuator 4 to adjust the equipment posture in real time.

[0023] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A control system for automatic welding equipment of corrugated plates of LNG ships (1), characterized in that: It includes a welding system (3), a motion actuator (4), a control system (1) and a sensor system (2). The control system (1) comprises a PLC industrial computer (101), a coupler (104) and a communication module (105); the PLC industrial computer (101) is electrically connected to the communication module (105) via the coupler (104). The motion actuator (4) comprises a reducer (401), a servo motor (402) and a servo controller (403), wherein the servo controller (403) is electrically connected to the servo motor (402), and the servo controller (403) is electrically connected to the communication module (105). The sensing system (2) comprises a first point laser sensor (201), a second point laser sensor (202), an inclination sensor (203), a contact displacement sensor (204) and a proximity sensor (205); the first point laser sensor (201), the second point laser sensor (202), the contact displacement sensor (204) and the proximity sensor (205) are all electrically connected to the communication module (105); the first point laser sensor (201) is arranged at the front end of the motion actuator (4) in the motion direction; the second point laser sensor (202) is arranged between the first point laser sensor (201) and the motion actuator (4); the contact displacement sensor (204) comprises a sensor head and a tail amplifier; the inclination sensor (203) is arranged on the motion actuator (4); The welding system (3) comprises a transformer (301), a water cooler (302) and a welding power source (303); the welding power source (303) is electrically connected to the communication module (105).

2. The LNG ship corrugated plate automatic welding equipment control system (1) according to claim 1, characterized in that: The servo motor (402) comprises an X-axis servo motor, a Y-axis servo motor, a Z-axis servo motor, an S-axis servo motor, and an R-axis servo motor.

3. The LNG ship corrugated plate automatic welding equipment control system (1) according to claim 1, characterized in that: The communication module (105) comprises an analog signal input and output module and a digital signal input and output module.

4. The LNG ship corrugated plate automatic welding equipment control system (1) according to claim 1, characterized in that: The control system (1) further comprises a touch screen (102) and a remote controller (103), wherein the touch screen (102) and the remote controller (103) are both electrically connected to the PLC industrial control computer (101).

5. A control method using the LNG ship corrugated plate automatic welding equipment control system (1) according to claim 1, characterized in that: When the sensor head at the top of the contact displacement sensor (204) contacts the corrugated plate, the corrugation and the plane are judged by the height change and used as error tracking, and the starting position of the corrugation is distinguished by the height change of the front and rear points; The first point laser sensor (201) measures the distance between the first point laser sensor (201) and the corrugated plate in real time, and senses the corrugated structure in the direction of movement of the equipment; when the first point laser sensor (201) measures the corrugated structure, the PLC industrial control computer (101) transmits a control signal to the motion actuator (4) according to the identified corrugated features, and executes preset action instructions such as climbing over the corrugations; The second point laser sensor (202) swings left and right, and samples with a period of 50 ms and an interval of 2 ms, and collects the distance between the second point laser sensor (202) and the corrugated plate in real time. Based on the height difference of 1.2 mm at the lap weld of the corrugated plate, the PLC industrial control computer (101) performs digital-to-analog conversion on the collected data, sets parameter judgment conditions, and sends a control signal to the motion actuator (4) when the midpoint deviates from the weld, and the motion actuator (4) adjusts the motion direction according to the signal; The inclination sensor (203) monitors the position of the equipment and the state of crossing the ripples in real time, and transmits the collected mechanism inclination information to the PLC industrial control computer (101) in real time. After calculation, the industrial control computer sends a control instruction to the motion execution mechanism (4) to adjust the equipment posture in real time.

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