Method and system for detecting tightness of cargo hold of ship

Abstract

This invention discloses a method and system for testing the tightness of ship cargo holds. The method is used to test the airtightness of the cargo hold after the hatch is closed. The steps are as follows: First, confirm that there is no interference within a predetermined range at the location to be tested. After confirming no interference, open the hatch, place an ultrasonic transmitter at a first position in the cargo hold and start it with a first transmission intensity. Use an ultrasonic detector to collect the signal intensity at a second position as the opening value and adjust the transmitter so that the opening value falls within a preset range. Then, close the hatch and collect the signal intensity at the location to be tested as the actual value. Compare the opening value with the actual value to determine the tightness of the location to be tested. This method first eliminates environmental interference and avoids the influence of environmental noise. A standardized reference opening value is obtained through adjustment. After the hatch is closed, the actual value is collected, and the determination is achieved by comparing the two sets of values, forming a standardized ultrasonic tightness testing process for ship cargo holds.

Description

Technical Field

[0001] This invention relates to the field of tightness testing technology, and in particular to a method and system for tightness testing of ship cargo holds. Background Technology

[0002] Currently, the weather tightness test for ship cargo holds commonly uses the water flushing test method. During the test, inspectors must enter the hold while water is being flushed from the outside, and visually inspect each flushed area using a strong flashlight, maintaining synchronization with the outside via walkie-talkie. After flushing, it is necessary to wait for the water to drain completely or for compressed air to dry the hold before opening the hatch to inspect for watermarks on the inside of the rubber seals.

[0003] However, the flushing test method has many inherent drawbacks: First, it consumes a large amount of water and requires the treatment of water accumulation inside the hold; second, the working environment for inspectors is relatively harsh and the labor intensity is high; third, the testing process involves multiple steps such as flushing, draining, and opening the hatch for inspection, which is inefficient, especially when there are many hatches on large container ships, the test cycle is significantly lengthened, which restricts the construction and dock repair progress; fourth, the judgment results rely on the visual experience and subjective observation of inspectors, lack objective quantitative standards, and are prone to missed detections or misjudgments.

[0004] Therefore, there is an urgent need for a relatively objective and quantitative method for density testing that can avoid the problems of lengthy testing procedures and water accumulation after testing. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to overcome the shortcomings of existing tightness testing methods, such as high water consumption, easy water accumulation, lengthy testing process, high labor intensity, and reliance on the subjective visual inspection of operators, and to provide a tightness testing method and system for ship cargo holds.

[0006] The present invention solves the above-mentioned technical problems through the following technical solution:

[0007] This invention provides a method for testing the tightness of a ship's cargo hold, used to test the sealing performance of the cargo hold's hatch when it is closed on the cargo hold hull. The method for testing the tightness of a ship's cargo hold includes the following steps:

[0008] Step S1: Confirm that there is no interference within the predetermined range surrounding the detected location;

[0009] Step S2: After confirming that there is no interference, open the hatch, place the ultrasonic transmitter in the first position of the ship's cargo hold, and turn on the ultrasonic transmitter with the first emission intensity. Use the probe of the ultrasonic detector to detect the signal strength at the second position, record it as the opening value, and adjust the ultrasonic transmitter so that the opening value is within the preset range.

[0010] Step S3: Close the hatch onto the cabin body, detect the signal strength at the detected location, and record it as the actual value;

[0011] Step S4: Compare the opening value with the actual value to determine the density at the detected location.

[0012] Step S1 involves confirming the absence of surrounding interference while the ultrasonic transmitter is off, eliminating the initial impact of environmental noise on the detection. Step S2 involves opening the hatch and adjusting the emission intensity to ensure the opening value is within a preset range, establishing a quantifiable benchmark. Step S3 involves closing the hatch and detecting the signal strength at the detected location to obtain the measured value under actual sealing conditions. Step S4 involves comparing the opening value with the actual value to provide an objective basis for tightness determination, thereby achieving a systematic and repeatable cargo hold tightness detection process.

[0013] Preferably, in step S2, placing the ultrasonic transmitter in a first position in the ship's cargo hold and activating the ultrasonic transmitter includes:

[0014] Confirm whether the reading of the ultrasonic detector exceeds its upper limit or triggers an alarm due to an excessively strong signal.

[0015] If the reading of the ultrasonic detector exceeds its upper limit or triggers an alarm due to an excessively strong signal, the first emission intensity of the ultrasonic transmitter is reduced; and / or the first position of the ultrasonic transmitter is adjusted to a reference position further away from the ultrasonic detector.

[0016] For situations where the ultrasonic detector reading exceeds the range or triggers an excessively strong alarm, the first emission intensity of the ultrasonic transmitter is reduced, and / or the transmitter is moved to a reference position farther away from the detector. This allows the detector's received signal to return to the linear response range, avoiding reading distortion caused by signal saturation and ensuring the accuracy and reliability of calibration and subsequent testing.

[0017] Preferably, in step S2, if the ultrasonic detector cannot read a valid signal strength, the following measures are taken: increasing the first emission intensity of the ultrasonic transmitter; and / or dividing the cargo compartment into multiple sub-detection areas, and placing the ultrasonic transmitter in each of the sub-detection areas sequentially for segmented calibration and segmented detection.

[0018] For situations where ultrasonic detectors cannot read effective signals, the method can be adapted to cargo holds of different sizes and shapes by increasing the first transmission intensity to compensate for the attenuation of the far-end signal, or by dividing the cargo hold into multiple sub-detection areas and performing segmented calibration and detection in sequence, thus effectively expanding the applicability of the detection method.

[0019] Preferably, in step S2, the first position is the center of the bottom of the ship's cargo hold;

[0020] And / or, the second position is the top corner of the hatch of the ship's cargo hold that is furthest from the ultrasonic transmitter;

[0021] And / or, the detected location is the connection point between the hatch and the cabin body.

[0022] By defining the first location as the center of the cabin floor, the ultrasonic signal radiates evenly outwards from this center, achieving balanced sound field coverage throughout the cabin. The second location is defined as the top corner of the hatch, furthest from the transmitter, facilitating quick positioning and reading by operators. The detection location is defined as the connection between the hatch cover and the cabin body, allowing the detection to directly target the critical sealing interface and enhancing the specificity of the detection.

[0023] Preferably, in step S2, after reading the opening value, the method further includes:

[0024] Select at least one other apex position of the hatch of the ship's cargo hold as the third position, place the ultrasonic detector at the third position to take a reading and record it as a verification reading. If the deviation between each verification reading and the opening value is within a predetermined allowable range, then the opening value is confirmed to be valid.

[0025] By verifying the readings at other apex positions of the hatch and comparing the deviation with the opening value, the uniformity of the sound field distribution in the cargo hold was effectively verified, ensuring the representativeness of the opening value reference and the effectiveness of the calibration, and avoiding deviations in the value of a single reference point caused by obstruction by foreign objects or distortion of the sound field in the hold.

[0026] Preferably, in step S4, if the percentage of the actual value to the opening value is greater than 10%, it is determined that there is leakage at the detected location; if the percentage of the actual value to the opening value is greater than 0% and not greater than 10%, it is determined that there is a minor leak at the detected location but the overall tightness is qualified; if the percentage of the actual value to the opening value is 0%, it is determined that the tightness at the detected location is good.

[0027] By quantifying the leakage judgment threshold to 10% of the opening value and establishing a three-level quantification standard, a clear and explicit grading judgment basis is provided for on-site inspection, enabling accurate differentiation of sealing status.

[0028] Preferably, in step S2, the preset range is 40dB to 60dB. When the opening value is outside the preset range, the emission intensity of the ultrasonic transmitter is readjusted so that the opening value is within the preset range.

[0029] By limiting the preset range of the aperture value to 40dB to 60dB, the ultrasonic emission intensity is matched with the cargo hold space size, ensuring that the detector operates in a high-sensitivity linear response region throughout the entire detection range. This avoids insufficient sensitivity due to an overly weak reference signal or saturation distortion due to an overly strong reference signal, thereby reducing measurement errors.

[0030] Preferably, during the detection process in step S3, if the ultrasonic detector does not output a regular alarm sound, but the signal strength received by the ultrasonic detector exceeds a preset value, then the signal strength is not taken as the actual value.

[0031] By excluding the signal from the actual value when the ultrasonic detector does not output a regular alarm sound but the received signal strength exceeds the preset value during the detection process, abnormal signals generated by non-leakage sources can be effectively prevented from being misjudged as leaks, thus improving the authenticity and reliability of the detection results.

[0032] The present invention also provides a tightness detection system for performing the tightness detection method for a ship's cargo hold as described above, the tightness detection system comprising:

[0033] An ultrasonic transmitter is used to continuously emit ultrasonic signals;

[0034] An ultrasonic detector is used to receive ultrasonic signals at the location being detected and to display the signal strength.

[0035] A sound output device, connected to the ultrasonic detector, is used to convert the received ultrasonic signal into an audible sound signal.

[0036] By integrating ultrasonic transmitters, ultrasonic detectors, and sound output devices into a tightness testing system, a systematic matching of testing equipment and methods is achieved, providing standardized hardware support for on-site testing, facilitating standardized operations by operators, and improving the efficiency and consistency of testing implementation.

[0037] Preferably, the ultrasonic transmitter includes multiple emitting electrodes, and the ultrasonic waves emitted by each emitting electrode propagate in a radial straight line in various directions.

[0038] By setting multiple emitters, ultrasonic waves are made to propagate in a straight line in a radial pattern in all directions, forming a sound field that uniformly covers the entire cargo hold area in three-dimensional space. This effectively eliminates the sound field blind spots that may be generated by single-direction emission, ensuring that each apex of the hatch and each section of the sealing interface can receive an effective reference signal.

[0039] The positive and progressive effects of this invention are as follows: Step S1 confirms that there is no interference in the surrounding environment while the ultrasonic transmitter is off, eliminating the initial influence of environmental noise on the detection; Step S2 opens the hatch and adjusts the emission intensity to make the opening value within a preset range, establishing a quantifiable benchmark reference; Step S3 detects the signal strength at the detected position after closing the hatch to obtain the measured value under actual sealing conditions; Step S4 provides an objective basis for tightness determination by comparing the opening value with the actual value, thereby realizing a systematic and repeatable cargo hold tightness detection process. Attached Figure Description

[0040] Figure 1 This is a flowchart illustrating the method for testing the tightness of a ship's cargo hold.

[0041] Figure 2 This is a schematic diagram showing an ultrasonic detector placed at the center of the bottom of a ship's cargo hold.

[0042] Figure 3 This is a schematic diagram of the connection structure of the airtightness detection system.

[0043] Explanation of reference numerals in the attached figures:

[0044] Tightness Detection System 1

[0045] Ultrasonic transmitter 10

[0046] Ultrasonic detector 20

[0047] Probe 21

[0048] Sound output device 30

[0049] Ship cargo hold 4

[0050] 41 pod

[0051] hatch 42 Detailed Implementation

[0052] The present invention will be further illustrated by way of embodiments below, but the present invention is not limited to the scope of the embodiments described herein.

[0053] like Figures 1-2 As shown, the present invention provides a method for testing the tightness of a ship's cargo hold 4, used to test the sealing performance of the hatch cover 42 of the ship's cargo hold 4 when it is covered by the hull 41 of the ship's cargo hold 4. The method for testing the tightness of a ship's cargo hold 4 includes the following steps:

[0054] Step S1: Confirm that there is no interference within the predetermined range surrounding the detected location;

[0055] Step S2: After confirming that there is no interference, open the hatch 42, place the ultrasonic transmitter 10 in the first position of the ship's cargo hold 4, and turn on the ultrasonic transmitter 10 with the first emission intensity. Use the probe 21 of the ultrasonic detector 20 to detect the signal strength at the second position, record it as the opening value, and adjust the ultrasonic transmitter 10 so that the opening value is within the preset range.

[0056] Step S3: Close the hatch 42 onto the cabin 41, detect the signal strength at the detected location, and record it as the actual value;

[0057] Step S4: Compare the opening value with the actual value to determine the tightness at the detected location.

[0058] In this embodiment, step S1 involves confirming the absence of surrounding interference while the ultrasonic transmitter 10 is off, eliminating the initial impact of environmental noise on the detection. Step S2 involves opening the hatch 42 and adjusting the emission intensity to ensure the opening value is within a preset range, establishing a quantifiable benchmark. Step S3 involves closing the hatch 42 and detecting the signal strength at the detected location to obtain the measured value under actual sealing conditions. Step S4 involves comparing the opening value with the actual value to provide an objective basis for tightness determination, thereby achieving a systematic and repeatable cargo hold tightness detection process.

[0059] like Figures 1-2 As shown, in step S2, placing the ultrasonic transmitter 10 in the first position of the ship's cargo hold 4 and turning on the ultrasonic transmitter 10 includes: confirming whether the reading of the ultrasonic detector 20 exceeds its upper limit or triggers an alarm due to an excessively strong signal; if the reading of the ultrasonic detector 20 exceeds its upper limit or triggers an alarm due to an excessively strong signal, then reducing the first emission intensity of the ultrasonic transmitter 10; and adjusting the first position of the ultrasonic transmitter 10 to a reference position further away from the ultrasonic detector 20.

[0060] In this embodiment, for situations where the ultrasonic detector 20 reading exceeds its range or triggers an excessively strong alarm, the first emission intensity of the ultrasonic transmitter 10 is reduced, and / or the transmitter is moved to a reference position further away from the detector, so that the received signal of the detector returns to the linear response range, avoiding reading distortion caused by signal saturation, and ensuring the accuracy and reliability of calibration and subsequent testing.

[0061] like Figures 1-2 As shown, in step S2, if the ultrasonic detector 20 cannot read a valid signal strength, the following measures are taken: increase the first emission strength of the ultrasonic transmitter 10; or divide the cargo compartment into multiple sub-detection areas and place the ultrasonic transmitter 10 in each sub-detection area in sequence for segmented calibration and segmented detection.

[0062] In this embodiment, for situations where the ultrasonic detector 20 cannot read effective signals, the method can be adapted to cargo holds of different sizes and shapes by increasing the first transmission intensity to compensate for the attenuation of the far-end signal, or by dividing the cargo hold into multiple sub-detection areas and performing segmented calibration and detection in sequence, thereby effectively expanding the applicability of the detection method.

[0063] like Figures 1-2 As shown, in step S2, the first position is the center of the bottom of the ship's cargo hold 4; the second position is the top corner of the hatch of the ship's cargo hold 4, which is furthest from the ultrasonic transmitter 10; and the detected position is the connection between the hatch cover 42 and the hull 41.

[0064] In this embodiment, by defining the first position as the center of the cabin floor, the ultrasonic signal is made to radiate evenly in all directions from this center, achieving balanced sound field coverage throughout the cabin. The second position is defined as the top corner of the hatch, which is furthest from the transmitter, facilitating quick positioning and reading by the operator. The detection location is defined as the connection between the hatch cover 42 and the cabin body 41, allowing the detection to directly target the critical sealing interface and enhancing the targeting of the detection.

[0065] like Figures 1-2 As shown, in step S2, after reading the opening value, the process further includes: selecting at least one other apex position of the hatch of the ship's cargo hold 4 as a third position, placing the ultrasonic detector 20 at the third position to take a reading and recording it as a verification reading. If the deviation between each verification reading and the opening value is within a predetermined allowable range, the opening value is confirmed to be valid. In this embodiment, the deviation between the verification reading and the opening value is less than 2% of the opening value, which confirms the opening value as valid. In other embodiments, other predetermined allowable ranges can also be set to determine whether the opening value is valid.

[0066] In this embodiment, by taking verification readings at other apex positions of the hatch and comparing the deviation with the opening value, the uniformity of the sound field distribution in the cargo hold is effectively verified, ensuring the representativeness of the opening value reference and the effectiveness of the calibration, and avoiding deviations in the value of a single reference point caused by obstruction by foreign objects in the hold or distortion of the sound field.

[0067] like Figures 1-2 As shown, in step S4, if the percentage of the actual value to the opening value is greater than 10%, it is determined that there is leakage at the detected location; if the percentage of the actual value to the opening value is greater than 0% and not greater than 10%, it is determined that there is a minor leak at the detected location but the overall tightness is qualified; if the percentage of the actual value to the opening value is 0%, it is determined that the tightness at the detected location is good.

[0068] In this embodiment, by quantifying the threshold for leakage determination to 10% of the opening value and establishing a three-level quantification standard, a clear and explicit grading judgment basis is provided for on-site inspection, thereby achieving accurate differentiation of sealing status.

[0069] like Figures 1-2 As shown, in step S2, the preset range is 40dB to 60dB. When the opening value is outside the preset range, the emission intensity of the ultrasonic transmitter 10 is readjusted so that the opening value is within the preset range.

[0070] In this embodiment, by limiting the preset range of the aperture value to 40dB to 60dB, the ultrasonic emission intensity is matched with the cargo hold space size, ensuring that the detector operates in the high-sensitivity linear response region throughout the entire detection range. This avoids insufficient sensitivity due to an overly weak reference signal or saturation distortion due to an overly strong reference signal, thereby reducing measurement errors.

[0071] like Figures 1-2 As shown, during the detection process in step S3, if the ultrasonic detector 20 does not output a regular alarm sound, but the signal strength received by the ultrasonic detector 20 exceeds a preset value, then the signal strength is not taken as the actual value. In this embodiment, the preset value is set to 20dB, but in other embodiments, the preset value can be set to other values ​​according to actual usage requirements. This part belongs to the prior art in this field and will not be described in detail here.

[0072] In this embodiment, when the ultrasonic detector 20 does not output a regular alarm sound but the received signal strength exceeds a preset value during the detection process, the signal is excluded and not taken as the actual value. This can effectively avoid misjudging abnormal signals generated by non-leakage sources as leaks, thereby improving the authenticity and reliability of the detection results.

[0073] like Figure 2 and Figure 3 As shown, the present invention also provides a tightness detection system 1 for performing the tightness detection method of the ship's cargo hold 4 as described above. The tightness detection system 1 includes: an ultrasonic transmitter 10 for continuously emitting ultrasonic signals; an ultrasonic detector 20 for receiving ultrasonic signals at the detection location and displaying the signal intensity; and a sound output device 30 connected to the ultrasonic detector 20 for converting the received ultrasonic signals into audible sound signals.

[0074] In this embodiment, by integrating the ultrasonic transmitter 10, ultrasonic detector 20, and sound output device 30 into a tightness detection system 1, the detection equipment and method are systematically matched, providing standardized hardware support for on-site detection, facilitating standardized operation by operators, and improving the efficiency and consistency of detection implementation.

[0075] like Figure 2 and Figure 3 As shown, the ultrasonic transmitter 10 includes six transmitting electrodes, and the ultrasonic waves emitted by each transmitting electrode propagate in a radial straight line in various directions.

[0076] In this embodiment, by setting multiple emitters, the ultrasonic waves are made to propagate in a radial straight line in all directions, forming a sound field that uniformly covers the entire cargo hold area in three-dimensional space. This effectively eliminates the sound field blind zone that may be generated by emission in a single direction, ensuring that each apex of the hatch and each section of the sealing interface can receive an effective reference signal.

[0077] While specific embodiments of the present invention have been described above, those skilled in the art should understand that these are merely illustrative examples, and the scope of protection of the present invention is defined by the appended claims. Those skilled in the art can make various changes or modifications to these embodiments without departing from the principles and essence of the present invention, but all such changes and modifications fall within the scope of protection of the present invention.

Claims

1. A method for testing the tightness of a ship's cargo hold, used to test the sealing performance of the cargo hold's hatch cover when it is installed on the hull of the ship's cargo hold, characterized in that, The method for testing the tightness of a ship's cargo hold includes the following steps: Step S1: Confirm that there is no interference within the predetermined range surrounding the detected location; Step S2: After confirming that there is no interference, open the hatch, place the ultrasonic transmitter in the first position of the ship's cargo hold, and turn on the ultrasonic transmitter with the first emission intensity. Use the probe of the ultrasonic detector to detect the signal strength at the second position, record it as the opening value, and adjust the ultrasonic transmitter so that the opening value is within the preset range. Step S3: Close the hatch onto the cabin body, detect the signal strength at the detected location, and record it as the actual value; Step S4: Compare the opening value with the actual value to determine the density at the detected location.

2. The method for detecting the tightness of a ship's cargo hold as described in claim 1, characterized in that, In step S2, placing the ultrasonic transmitter in the first position of the ship's cargo hold and activating the ultrasonic transmitter includes: Confirm whether the reading of the ultrasonic detector exceeds its upper limit or triggers an alarm due to an excessively strong signal. If the reading of the ultrasonic detector exceeds its upper limit or triggers an alarm due to an excessively strong signal, the first emission intensity of the ultrasonic transmitter is reduced; and / or the first position of the ultrasonic transmitter is adjusted to a reference position further away from the ultrasonic detector.

3. The method for detecting the tightness of a ship's cargo hold as described in claim 1, characterized in that, In step S2, if the ultrasonic detector cannot read a valid signal strength, the following measures are taken: increase the first emission intensity of the ultrasonic transmitter; and / or divide the cargo compartment into multiple sub-detection areas, and place the ultrasonic transmitter in each of the sub-detection areas in sequence for segmented calibration and segmented detection.

4. The method for detecting the tightness of a ship's cargo hold as described in claim 1, characterized in that, In step S2, the first position is the center of the bottom of the ship's cargo hold; And / or, the second position is the top corner of the hatch of the ship's cargo hold that is furthest from the ultrasonic transmitter; And / or, the detected location is the connection point between the hatch and the cabin body.

5. The method for detecting the tightness of a ship's cargo hold as described in claim 4, characterized in that, In step S2, after reading the opening value, the method further includes: Select at least one other apex position of the hatch of the ship's cargo hold as the third position, place the ultrasonic detector at the third position to take a reading and record it as a verification reading. If the deviation between each verification reading and the opening value is within a predetermined allowable range, then the opening value is confirmed to be valid.

6. The method for detecting the tightness of a ship's cargo hold as described in claim 1, characterized in that, In step S4 If the percentage of the actual value to the opening value is greater than 10%, it is determined that there is leakage at the detected location; If the percentage of the actual value and the opening value is greater than 0% and not greater than 10%, it is determined that there is a slight leak at the detected location but the overall tightness is qualified. If the percentage of the actual value to the opening value is 0%, then the density at the detected location is determined to be good.

7. The method for detecting the tightness of a ship's cargo hold as described in claim 1, characterized in that, In step S2, the preset range is 40dB to 60dB. When the opening value is outside the preset range, the emission intensity of the ultrasonic transmitter is readjusted so that the opening value is within the preset range.

8. The method for detecting the tightness of a ship's cargo hold as described in claim 1, characterized in that, During the detection process in step S3, if the ultrasonic detector does not output a regular alarm sound, but the signal strength received by the ultrasonic detector exceeds a preset value, then the signal strength is not taken as the actual value.

9. A tightness detection system for performing the tightness detection method for a ship's cargo hold as described in any one of claims 1 to 8, characterized in that, The tightness detection system includes: An ultrasonic transmitter is used to continuously emit ultrasonic signals; An ultrasonic detector is used to receive ultrasonic signals at the location being detected and to display the signal strength. A sound output device, connected to the ultrasonic detector, is used to convert the received ultrasonic signal into an audible sound signal.

10. The tightness detection system as described in claim 9, characterized in that, The ultrasonic transmitter includes multiple emitting electrodes, and the ultrasonic waves emitted by each emitting electrode propagate in a radial straight line in various directions.

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