Method for preventing cracking of a rod sensor of an electromagnetic log and electromagnetic log

Abstract

The present application relates to the technical field of electromagnetic log design, in particular to a method for preventing the rod sensor of an electromagnetic log from cracking and the electromagnetic log. The method comprises the following steps: setting a strain force type sensor, and setting a preset force range to be greater than the stress of the rod sensor in the extended state under the normal navigation of the ship and less than the stress of the rod sensor in the extended state when the rod sensor is hung with a net or subjected to other external forces. The method can ensure that the rod sensor remains in the extended state when the ship is normally navigated, and can be timely retracted when the rod sensor is hung with a net or subjected to other external forces, thereby preventing the rod sensor from cracking.

Description

Technical Field

[0001] This invention relates to the technical field of electromagnetic log design, and in particular to a method for preventing cracking of the rod sensor of an electromagnetic log and the electromagnetic log itself. Background Technology

[0002] Most ships are equipped with electromagnetic logs, which are used to measure the ship's speed and accumulate distance, providing real-time speed and distance information. This equipment is essential for ship navigation, and its main functions include: measuring and displaying speed and distance; providing speed measurement field calibration; and transmitting speed and distance information externally. The equipment consists of a planar sensor, a gate assembly (commonly known as a sluice gate valve), an amplifier, a rod sensor, an automatic lifting device, and the main instrument. The rod sensor differs from the planar sensor in terms of speed measurement accuracy and water layer sensitivity. Planar sensors are generally used as rod sensors in areas where speed measurement is inconvenient, such as fishing net areas.

[0003] During multiple vessel voyages, it was observed that when the rod sensor was in the extended position and continuously operating, and the vessel approached near-shore anchorages or other near-shore areas, personnel found that the electromagnetic log rod channel displayed no speed information. Considering safety concerns, the rod sensor was inspected after docking. Inspectors discovered that the rod sensor frequently snagged fishing nets during use, causing the insulation of the sensor's excitation coil to drop to 0Ω. Disassembly revealed a crack at the connection between the copper head and the outer casing of the rod sensor, leading to water accumulation inside the rod and resulting in the electromagnetic log rod channel displaying no speed information.

[0004] Once this phenomenon occurs, the existing solutions, in addition to replacing the rod sensor, also require re-calibrating the accuracy, resulting in repeated waste of the ship's fuel, manpower, and material resources. Summary of the Invention

[0005] To at least partially solve the aforementioned problems in the prior art, the present invention provides a method for preventing cracking of the rod sensor of an electromagnetic log and an electromagnetic log.

[0006] A method for preventing cracking of a rod sensor in an electromagnetic odometer, the electromagnetic odometer including a rod sensor and an automatic lifting device, the automatic lifting device being used to control the extension or retraction of the rod sensor, the method comprising:

[0007] A strain gauge sensor is provided on the outer surface of the rod sensor, and the strain gauge sensor is electrically connected to the automatic lifting device.

[0008] When the strain gauge sensor detects that the surface pressure of the rod sensor exceeds a preset force range, the automatic lifting device is controlled to retract the rod sensor. The preset force range is greater than the force exerted on the ship during normal navigation when the rod sensor is extended, but less than the force exerted on the rod sensor when it is caught on a net or subjected to other external forces.

[0009] Optionally, determining the magnitude of the force exerted on the rod sensor when it is extended and attached to a net or subjected to other external forces includes:

[0010] Based on the material of the rod sensor, the first maximum deformation is determined by referring to a table.

[0011] The second maximum deformation is determined based on the lifting gap between the rod sensor and the automatic lifting device;

[0012] The smaller value between the first maximum deformation and the second maximum deformation is determined as the final deformation.

[0013] By combining structural statics simulation analysis, the final deformation is applied to the simulation model of the rod sensor. Through simulation calculation, the magnitude of the force on the rod sensor when it is extended and hung on a net or subjected to other external forces can be automatically output.

[0014] Optionally, the preset force range can be selected as the intermediate value of the force when the ship is sailing normally in the extended state of the rod sensor and when it is caught in a net or subjected to other external forces.

[0015] Optionally, the method further includes increasing the air pressure of the lifting cylinder to increase the speed at which the lifting cylinder retracts the rod sensor.

[0016] An electromagnetic odometer includes a rod sensor, an automatic lifting device, and a strain gauge sensor. The strain gauge sensor covers the outer surface of the rod sensor. Both the rod sensor and the strain gauge sensor are electrically connected to the automatic lifting device. The automatic lifting device is configured to control the rod sensor to retract when the strain gauge sensor detects that the surface pressure of the rod sensor exceeds a preset force range. The preset force range is greater than the force exerted on the ship during normal navigation when the rod sensor is extended, but less than the force exerted on the rod sensor when it is caught in a net or subjected to other external forces.

[0017] Optionally, the automatic lifting device includes a lifting cylinder and a control box, and both the lifting cylinder and the strain sensor are communicatively connected to the control box.

[0018] On the one hand, in a method for preventing the rod sensor of an electromagnetic logger from cracking according to the present invention, a strain gauge sensor is set, and the preset force range is set to be greater than the force on the ship during normal navigation when the rod sensor is extended and less than the force on the rod sensor when it is caught in a net or subjected to other external forces. This ensures that the rod sensor remains extended during normal navigation and can be retracted in time when the rod sensor is caught in a net or subjected to other external forces, thereby preventing the rod sensor from cracking.

[0019] On the other hand, in an electromagnetic odometer of the present invention, by setting a strain gauge sensor and setting the preset force range to be greater than the force on the ship during normal navigation when the rod sensor is extended and less than the force on the rod sensor when it is caught in a net or subjected to other external forces, it can ensure that the rod sensor remains extended during normal navigation and can be retracted in time when the rod sensor is caught in a net or subjected to other external forces, thereby preventing the rod sensor from cracking. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the structure of a rod-type sensor and a strain force sensor according to an embodiment of the present invention;

[0021] Figure 2 This is a structural schematic diagram illustrating the lifting clearance according to an embodiment of the present invention. Detailed Implementation

[0022] The following reference Figure 1 and Figure 2 This invention describes a method for preventing cracking of the rod sensor of an electromagnetic log and an electromagnetic log.

[0023] refer to Figure 1 and Figure 2 This invention provides a method for preventing cracking of the rod sensor in an electromagnetic odometer. The electromagnetic odometer includes a rod sensor 1 and an automatic lifting device 2. The automatic lifting device 2 is used to control the extension or retraction of the rod sensor 1. The method includes:

[0024] A strain sensor 3 is covered on the outer surface of the rod sensor 1, and the strain sensor 3 is electrically connected to the automatic lifting device 2.

[0025] When the strain gauge sensor 3 detects that the surface pressure of the rod sensor 1 exceeds the preset force range, the automatic lifting device 2 is controlled to retract the rod sensor 1. The preset force range is greater than the force exerted on the ship during normal navigation when the rod sensor 1 is extended, but less than the force exerted on the rod sensor 1 when it is caught on a net or subjected to other external forces while extended.

[0026] During normal navigation, the rod sensor 1 deforms under stress. When the rod sensor 1 gets caught in a net or is subjected to other external forces, the stress on the rod sensor 1 increases, leading to increased deformation and potentially causing cracking at the connection between the copper head and the outer casing. Therefore, by installing a strain gauge sensor 3 and setting the preset force range to be greater than the force experienced by the rod sensor 1 during normal navigation but less than the force experienced when the rod sensor 1 is caught in a net or subjected to other external forces, the rod sensor 1 can be kept in the extended state during normal navigation and can be retracted promptly when caught in a net or subjected to other external forces, thus preventing cracking.

[0027] It should be noted that the preset force range setting needs to reserve a certain amount of redundancy in order to reduce the impact of force fluctuations on the extension or retraction of the rod sensor 1 when the ship is sailing normally in the extended state, or when it is caught in a net or subjected to other external forces.

[0028] Furthermore, determining the magnitude of the force exerted on the rod sensor 1 when it is extended and the net is attached or subjected to other external forces includes:

[0029] Based on the material of the rod sensor 1, the first maximum deformation is determined by referring to a table. If the deformation of the rod sensor 1 exceeds the first maximum deformation, it will cause the rod sensor 1 to crack or undergo permanent deformation.

[0030] The second maximum deformation is determined based on the lifting gap 4 between the rod sensor 1 and the automatic lifting device 2. In other words, when the deformation of the rod sensor 1 exceeds the second maximum deformation, the bending degree of the rod sensor 1 exceeds the lifting gap 4 between the rod sensor 1 and the automatic lifting device 2, which will cause the rod sensor 1 to fail to retract properly.

[0031] The smaller of the first maximum deformation and the second maximum deformation is determined as the final deformation.

[0032] By combining structural statics simulation analysis, the final deformation is applied to the simulation model of rod sensor 1. Through simulation calculation, the magnitude of the force on rod sensor 1 when it is extended and attached to a net or subjected to other external forces can be automatically output. Structural statics simulation analysis is a common method for predicting mechanical scene parameters, and will not be elaborated here.

[0033] Optionally, the force exerted on the rod sensor 1 when it is extended and hung on a net or subjected to other external forces is 2000N.

[0034] Optionally, the preset force range can be selected as the intermediate value between the force exerted on the ship during normal navigation when the rod sensor 1 is extended and the force exerted when the ship is caught in a net or subjected to other external forces. Therefore, if the force exerted on the ship during normal navigation when the rod sensor 1 is extended is 1088N and the force exerted on the ship when the rod sensor 1 is extended and subjected to a net or other external forces is 2000N, the preset force range can be set to 1500N.

[0035] Furthermore, the method also includes increasing the air pressure of the lifting cylinder to increase the speed of the lifting cylinder retracting rod sensor 1. Optionally, the air pressure of the lifting cylinder can be increased to 1 MPa.

[0036] refer to Figure 1 and Figure 2 This invention also provides an electromagnetic odometer, including a rod sensor 1, an automatic lifting device 2, and a strain gauge sensor 3. The strain gauge sensor 3 covers the outer surface of the rod sensor 1, and both the rod sensor 1 and the strain gauge sensor 3 are electrically connected to the automatic lifting device 2. The automatic lifting device 2 is configured to control the rod sensor 1 to retract when the strain gauge sensor 3 detects that the surface pressure of the rod sensor 1 exceeds a preset force range. The preset force range is greater than the force experienced by the ship during normal navigation when the rod sensor 1 is extended, but less than the force experienced when the rod sensor 1 is caught in a net or subjected to other external forces during its extended state. By setting the strain gauge sensor 3 and setting the preset force range to be greater than the force experienced by the ship during normal navigation when the rod sensor 1 is extended, but less than the force experienced when the rod sensor 1 is caught in a net or subjected to other external forces during its extended state, it is possible to ensure that the rod sensor 1 remains extended during normal navigation and to retract it promptly when caught in a net or subjected to other external forces, thereby preventing the rod sensor 1 from cracking.

[0037] Furthermore, the automatic lifting device 2 includes a lifting cylinder and a control box. Both the lifting cylinder and the strain gauge sensor 3 are communicatively connected to the control box. After receiving the pressure acting on the surface of the rod sensor 1, the strain gauge sensor 3 first feeds back to the control box. The control box determines whether the pressure exceeds the preset force range. If it exceeds the preset force range, it controls the lifting cylinder to retract the rod sensor 1.

[0038] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. A method for preventing cracking of a rod sensor in an electromagnetic odometer, the electromagnetic odometer comprising a rod sensor and an automatic lifting device, the automatic lifting device being used to control the extension or retraction of the rod sensor, characterized in that, The method includes: A strain gauge sensor is provided on the outer surface of the rod sensor, and the strain gauge sensor is electrically connected to the automatic lifting device. When the strain gauge sensor detects that the surface pressure of the rod sensor exceeds a preset force range, the automatic lifting device is controlled to retract the rod sensor. The preset force range is greater than the force exerted on the ship during normal navigation when the rod sensor is extended, but less than the force exerted on the rod sensor when it is caught on a net or subjected to other external forces.

2. The method for preventing cracking of the rod sensor of an electromagnetic logger according to claim 1, characterized in that, Determining the magnitude of the force exerted on the rod sensor when it is extended and attached to a net or subjected to other external forces includes: Based on the material of the rod sensor, the first maximum deformation is determined by referring to a table. The second maximum deformation is determined based on the lifting gap between the rod sensor and the automatic lifting device; The smaller value between the first maximum deformation and the second maximum deformation is determined as the final deformation. By combining structural statics simulation analysis, the final deformation is applied to the simulation model of the rod sensor. Through simulation calculation, the magnitude of the force on the rod sensor when it is extended and hung on a net or subjected to other external forces can be automatically output.

3. The method for preventing cracking of the rod sensor of an electromagnetic logger according to claim 1, characterized in that, The preset force range can be selected as the intermediate value of the force when the ship is sailing normally in the extended state of the rod sensor and when it is caught in a net or subjected to other external forces.

4. The method for preventing cracking of the rod sensor of an electromagnetic logger according to claim 1, characterized in that, The method also includes increasing the air pressure of the lifting cylinder to increase the speed at which the lifting cylinder retracts the lever sensor.

5. An electromagnetic speedometer, characterized in that, The device includes a rod sensor, an automatic lifting device, and a strain gauge sensor. The strain gauge sensor is disposed on the outer surface of the rod sensor. Both the rod sensor and the strain gauge sensor are electrically connected to the automatic lifting device. The automatic lifting device is configured to control the rod sensor to retract when the strain gauge sensor detects that the surface pressure of the rod sensor exceeds a preset force range. The preset force range is greater than the force exerted on the ship during normal navigation when the rod sensor is extended, but less than the force exerted on the rod sensor when it is caught on a net or subjected to other external forces.

6. The electromagnetic speedometer according to claim 5, characterized in that, The automatic lifting device includes a lifting cylinder and a control box, and both the lifting cylinder and the strain sensor are communicatively connected to the control box.

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