Fin tube inner wall corrosion degree measuring assembly and device applying same

Abstract

This disclosure relates to a component and a device for measuring the degree of corrosion on the inner wall of a finned tube in an air cooler. The device includes: a conical slide body, two probe wheels, a pin, an elastic frame, a spring, a copper sleeve, a slender cylinder, a slender rod, a pointer, and a locking spring. The conical slide body has two tracks machined on its side, on which two probe wheels roll and adhere closely to the inner wall of the finned tube. The distance between the outer edges of the two probe wheels determines the inner diameter of the finned tube being measured and provides a magnified display of the measured dimensions. The slender rod has graduations and numerical dimensions for quantitatively indicating the inner diameter of the finned tube. The slender cylinder can move freely inside the finned tube, and the locking spring locks the slender rod to retract the probe wheels, preventing them from jamming inside the finned tube. This measuring device can be installed inside small-diameter finned tubes, has no optical or electronic components, is unaffected by residual liquid media inside the tube, provides accurate measurements, and has broad applicability.

Description

Technical Field

[0001] This disclosure relates to a pipe inner diameter measuring tool, and more specifically, to a measuring device for determining the degree of corrosion of the inner wall of an air cooler finned tube by measuring changes in its inner diameter. Background Technology

[0002] In industrial applications such as air coolers, finned tubes with large heat dissipation areas and small diameters are commonly used. The industrial media inside finned tubes are generally corrosive, and prolonged use can cause corrosion and thinning of the inner wall. Timely detection and assessment of the degree of corrosion on the inner wall of finned tubes can prevent sudden leaks.

[0003] The finned tubes of industrial air coolers are generally straight tube sections. Both ends of the finned tubes are connected to the tube box. On the outside of the tube box, there are inspection ports with threaded plugs for each finned tube, which are used for maintenance during production shutdowns and for sealing leaks in the finned tubes.

[0004] Currently, corrosion detection of the inner wall of finned tubes in industrial air coolers is generally carried out using optical instruments such as endoscopes for observation or electronic instruments such as ultrasonic waves for thickness measurement or flaw detection.

[0005] Endoscopes can be inserted into pipes to directly observe the condition of the pipe's inner wall. Examples include: a pipe endoscope (CN219737890U), a pipe endoscope (CN 217360447 U), a miniature high-definition pipe video endoscope camera and pipe endoscope (CN 217283090 U), and an intelligent device for detecting corrosion on the inner wall of buried steel pipes (CN210427374U). However, when using these endoscopes, the medium in the pipe must be thoroughly purged to remove any liquid residue, as this can affect the observation results. This leads to high detection requirements and low applicability. Furthermore, endoscopes are not effective at observing uniform corrosion thinning and cannot provide quantitative parameters of the degree of corrosion thinning.

[0006] Ultrasonic testing devices for pipelines are typically installed on the outside of the pipeline to measure the amount of wall thinning due to corrosion or to detect defects. Examples include a pipeline internal wall corrosion testing device (CN 219551451 U) and a gas pipeline internal wall corrosion testing device (CN 214844704U). However, due to the obstruction of the fins fixed to the outer wall of finned tubes, these instruments cannot be installed on one side of the finned tube's outer wall and cannot be used for flaw detection or measurement like ordinary pipelines.

[0007] Currently, some electronic instruments are designed to be installed inside pipelines for corrosion or defect detection, such as a gas pipeline internal wall corrosion detection device and system (CN 217786121 U) and a pipeline defect length inspection device and method (CN114910006A). However, residual liquid media in the pipeline can still affect the detection accuracy of electronic instruments or even prevent them from detecting defects; furthermore, the small diameter and complex structure of the finned tubes in air coolers make it difficult to install these electronic instruments inside for detection. Summary of the Invention

[0008] This disclosure presents a component for measuring the degree of corrosion of the inner wall of finned tubes, as well as an apparatus and method for applying it. The technical solution is simple and practical, the device has a simple structure and small radial dimension, and can be installed in finned tubes with small diameters for quantitative measurement of the inner diameter. Furthermore, the device has no optical or electronic components, and the measurement is not affected by the residual liquid medium inside the tube, making it highly applicable.

[0009] The first aspect of this disclosure is to provide a component for measuring the degree of corrosion on the inner wall of a finned tube, basic scheme 1: including a slender cylinder 7, which is unique in that:

[0010] The assembly also includes a conical slide body 1, two detection wheels 2, and two elastic frames 4;

[0011] The conical slide body is a frustum with a small cylinder at the top. Two straight slide tracks 101 are machined on the upper and lower sides of the small cylinder, and two oblique slide tracks 102 are machined on the upper and lower sides of the frustum. The straight slide tracks and the oblique slide tracks are aligned and connected to form the upper and lower slide tracks of the conical slide body. After being connected, the detection wheel can roll on the upper and lower slide tracks of the conical slide body.

[0012] Each of the elastic frames includes an elastic plate 401 and two lugs 402. The lugs 402 are disposed at the non-fixed end of the elastic plate, and the detection wheel 2 is mounted on the lugs via a pin 3.

[0013] The slender tube is a slender steel tube with an outer diameter smaller than the inner diameter of the finned tube 11, which can be inserted into the finned tube during use; threaded holes are machined on the upper and lower sides of the left end of the slender tube for mounting the two elastic frames with screws; the two elastic frames elastically press the two probe wheels onto the slide of the conical slide body 1, and the inner diameter of the finned tube is measured by the distance between the outer edges of the two probe wheels.

[0014] Furthermore, the ratio of the axial distance L to the radial lifting distance H corresponding to the inclined slide is a fixed value R, which is set to 4:1 or 6:1. That is, the radial movement distance of the two detection wheels in the finned tube corresponds to 2 or 3 times the axial movement distance of the conical slide body, which is used to realize the magnified display of the inner diameter measurement dimension of the finned tube.

[0015] The second aspect of this disclosure is to provide a device for measuring the degree of corrosion of the inner wall of a finned tube, which, in addition to the aforementioned finned tube inner wall corrosion measuring components, also uses a spring 5, two copper sleeves 6 and a slender rod 8.

[0016] The slender rod is longer than the slender tube 7 and can be inserted into the slender tube;

[0017] The left end of the slender rod is machined with a tapered sliding body connecting thread 801 for connecting the tapered sliding body 1;

[0018] Threads are machined into the inner holes at both ends of the slender cylinder, and the copper sleeves are installed to support and reduce the sliding resistance of the slender rod.

[0019] On the slender rod, a spring is provided between the conical slide body 1 and the copper sleeve 6 to press the conical slide body to move it to the left, causing the two probe wheels to press against the inner wall of the finned tube during measurement.

[0020] Furthermore, the right end of the slender rod is machined into a spherical head 804 for manually pushing and pulling the slender rod.

[0021] Furthermore, the device also includes a pointer 9 and a scale line 803 disposed on the right side of the slender rod 8;

[0022] The pointer is L-shaped and is fixed to the right side of the slender tube 7 by a screw, with the tip of the pointer pointing to the scale line.

[0023] The numbers on the scale line correspond to the inner diameter of the finned tube measured by the distance between the outer edges of the two probe wheels 2.

[0024] Furthermore, the device also includes a locking spring 10 and an annular groove 802;

[0025] The annular groove 802 is located to the left of the scale line 803 on the right end of the slender rod 8;

[0026] The locking spring is made of a thin plate bent into shape and is fixed to the right side of the slender tube 7 by screws. When the inner diameter of the finned tube 11 is not measured, the top of the locking spring is stuck in the annular groove, which can prevent the slender rod from moving axially relative to the slender tube, making it easier for the device to be pulled out of the finned tube 11.

[0027] A third aspect of this disclosure provides a method for measuring the degree of corrosion on the inner wall of an air cooler finned tube, using the aforementioned apparatus and following the steps below:

[0028] Hold the slender cylinder 7 in place by hand and pull the slender rod 8 to the right until the top of the locking spring 10 is stuck in the annular groove 802 of the slender rod. Under the action of the elastic frame 4, the two detection wheels 2 move closer to each other, reducing the radial distance.

[0029] Insert one end of the cone-shaped sliding body 1 and the probe wheel 2 on the left side of the device into the finned tube 11 through the tube box inspection port of the air cooler;

[0030] When the measurement begins, the locking spring is activated to unlock the device. Under the action of the spring 5, the conical slide body moves to the left and presses against the two probe wheels to move radially, thus adhering to the inner wall of the finned tube. The slender cylinder is pushed to move inside the finned tube. The inner diameter of the finned tube is read from the scale line 803 on the right side of the slender rod, thereby quantitatively measuring the amount of corrosion thinning of the inner wall of the finned tube.

[0031] After the measurement is completed, hold the slender tube in place by hand and pull the slender rod to the right until the top of the locking spring is engaged in the annular groove of the slender rod. Then, pull the device out of the finned tube and proceed to measure the next finned tube.

[0032] Furthermore, when the device detects a corrosion thinning zone on the inner wall of the finned tube, the elongated cylinder is rotated to different angles to measure and record the amount of corrosion thinning in the circumferential direction of that zone.

[0033] If the detection wheel gets stuck when moving from the area of ​​maximum corrosion to the area of ​​slight corrosion on the inner wall of the finned tube, hold the slender cylinder by hand and pull the slender rod to the right, so that the two detection wheels move closer to each other under the action of the elastic frame, reducing the radial distance and thus releasing the jam.

[0034] The above-described at least one technical solution adopted in one or more embodiments of this specification can achieve the following beneficial effects:

[0035] First, the device has a simple structure and small radial dimension, allowing it to be installed in small-diameter finned tubes. Second, the device has no optical or electronic components, and its measurements are unaffected by residual liquid media inside the tube, making it highly adaptable. Third, the device's slender rod has graduations and numerical dimensions, allowing for quantitative indication of the finned tube's inner diameter. Furthermore, the device can move freely inside the finned tube via a slender cylinder, and the locking spring secures the slender rod to retract the probe wheel, preventing jamming inside the finned tube.

[0036] In summary, the technical solution proposed in this invention is simple and practical, with a simple device structure and small radial dimensions, which can be installed in small-diameter finned tubes for quantitative measurement of inner diameter; furthermore, the device has no optical or electronic components, and the measurement is not affected by residual liquid media inside the tube, making it highly applicable.

[0037] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and are not intended to limit this disclosure.

[0038] Other features and aspects of this disclosure will become clear from the following detailed description of exemplary embodiments with reference to the accompanying drawings. Attached Figure Description

[0039] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this disclosure and, together with the specification, serve to illustrate the technical solutions of this disclosure.

[0040] Figure 1 This is a cross-sectional view of the device.

[0041] Figure 2 This is a cross-sectional front view of the conical sliding body.

[0042] Figure 3 This is a left view of the conical slide body.

[0043] Figure 4 This is the front view of the elastic frame.

[0044] Figure 5 This is a top view of the elastic frame.

[0045] Figure 6 This is a cross-sectional view of the slender cylinder.

[0046] Figure 7 This is a view of the slender rod.

[0047] Figure 8 This is a cross-sectional view of the pointer.

[0048] Figure 9 This is a cross-sectional view of the locking spring.

[0049] Figure 10 A cross-sectional view of the slender rod in a locked state after the device is inserted into the finned tube.

[0050] Figure 11 A cross-sectional view of the corrosion zone on the inner wall of the finned tube detected after the slender rod is unlocked for the device.

[0051] In the diagram: 1-conical slide body, 101-straight slide, 102-sloping slide, 103-threaded hole; 2-detector wheel; 3-pin; 4-elastic frame, 401-elastic plate, 402-support lug; 5-spring; 6-copper sleeve; 7-slender cylinder; 8-slender rod, 801-thread, 802-annular groove, 803-scale line, 804-spherical head; 9-pointer; 10-locking spring; 11-finned tube; 12-outer fins of the tube; 13-corrosion zone on the inner wall. Detailed Implementation

[0052] Various exemplary embodiments, features, and aspects of this disclosure will now be described in detail with reference to the accompanying drawings. The same reference numerals in the drawings denote elements that have the same or similar functions. Although various aspects of the embodiments are shown in the drawings, they are not necessarily drawn to scale unless specifically indicated otherwise.

[0053] Furthermore, to better illustrate this disclosure, numerous specific details are set forth in the following detailed description. Those skilled in the art will understand that this disclosure can be practiced without certain specific details. In some instances, methods, means, and elements well known to those skilled in the art have not been described in detail in order to highlight the main points of this disclosure.

[0054] like Figures 1-9 As shown, the device for measuring the corrosion degree of the inner wall of the air cooler finned tube includes one conical slide body, two detection wheels, two pins, two elastic frames, one spring, two copper sleeves, one slender cylinder, one slender rod, one pointer, and one locking spring.

[0055] The cone slide body 1 is shaped like a cone with a small cylinder. Two straight slide tracks 101 are machined on the upper and lower sides of the small cylinder, and two oblique slide tracks 102 are machined on the upper and lower sides of the cone. The straight slide tracks and the oblique slide tracks are aligned and connected. Two detection wheels 2 roll on the upper and lower slide tracks of the cone slide body and stick to the inner wall of the finned tube 11. The inner diameter of the finned tube is measured by the distance between the outer circles of the two detection wheels.

[0056] The ratio of the axial distance L to the radial rise distance H corresponding to the inclined slide on the conical slide body is a fixed value R. R is set to 4:1 or 6:1, that is, the radial movement distance of the two detection wheels in the finned tube corresponds to 2 or 3 times the axial movement distance of the conical slide body, which is used to realize the magnified display of the inner diameter measurement dimension of the finned tube.

[0057] The combination of the conical slide body 1 and the probe wheel 2 converts the radial distance of the probe wheel 2, which measures the inner diameter of the finned tube, into the axial movement distance of the conical slide body 1. The radial distance is magnified by 2 or 3 times and displayed as the axial movement distance by the ratio of the axial distance L corresponding to the inclined slide 102 to the radial rise distance H.

[0058] The elastic frame 4 consists of an elastic plate 401 and two lugs 402. The detection wheel 2 is mounted on the lug at the left end of the elastic frame via a pin 3. The slender tube 7 is a slender steel tube with an outer diameter smaller than the inner diameter of the finned tube 11. When the device is in use, the slender tube is inserted into the finned tube. Threaded holes are machined on the upper and lower sides of the left end of the slender tube, and two elastic frames are installed by screws. The two elastic frames elastically press the two detection wheels against the slide rail of the conical slide body 1.

[0059] The elastic frame 4 and the pin 3 are used to hinge and fix the probe wheel 2, ensuring that it rolls on the slide of the conical slide body 1 without coming off; the slender tube 7 is used to fix the elastic frame 4 and push the probe wheel 2 to move in the finned tube 11 for measurement.

[0060] The slender rod 8 is longer than the slender cylinder 7 and is inserted into the slender cylinder; the left end of the slender rod is threaded with a thread 801 and connected to the conical slide body 1; a small scale line 803 is provided on the side of the right end of the slender rod, and an annular groove 802 is machined on the left side of the scale line 803; the right end of the slender rod is machined into a spherical head 804 to facilitate manual pushing and pulling of the slender rod.

[0061] The slender rod 8 and the copper sleeve 6 work together to transmit the axial movement distance of the conical slide body 1 inside the finned tube 11 to the outside of the finned tube 11 for display.

[0062] Threads are machined into the inner holes at both ends of the slender cylinder, and two copper sleeves 6 are installed to support and reduce the sliding resistance of the slender rod. A spring 5 is set between the conical slide body 1 on the slender rod and the copper sleeve on the left side to press the conical slide body to move it to the left, so that the two probe wheels 2 are pressed against the inner wall of the finned tube 11 to ensure measurement accuracy.

[0063] The pointer 9 is L-shaped and is fixed to the right side of the slender tube 7 by screws. The tip of the pointer points to the scale line. The numbers on the scale line correspond to the inner diameter of the finned tube measured by the distance between the outer circles of the two probe wheels 2, thus achieving quantitative measurement. The pointer 9 and the scale line 803 work together to quantitatively display the measured inner diameter of the finned tube 11.

[0064] The locking spring 10 is made of a thin plate bent and is fixed to the right side of the slender tube 7 by screws. The locking spring 10 and the annular groove 802 cooperate to prevent the slender rod 8 from moving axially relative to the slender tube 7. When the inner diameter of the finned tube 11 is not measured, the top of the locking spring is stuck in the annular groove, which prevents the slender rod from moving axially relative to the slender tube, making it convenient for the device to be pulled out of the finned tube 11.

[0065] like Figure 10 and Figure 11 As shown, the specific method of using the device described in this invention is as follows:

[0066] After all the components of the device are installed, the slender cylinder 7 is fixed by hand while the slender rod 8 is pulled to the right until the top of the locking spring 10 is stuck in the annular groove 802 of the slender rod. Under the action of the elastic frame 4, the two detection wheels 2 move closer to each other, reducing the radial distance.

[0067] Insert one end of the cone-shaped sliding body 1 and the probe wheel 2 on the left side of the device into the finned tube 11 through the inspection port of the air cooler's tube box, as follows. Figure 10 As shown.

[0068] At the start of the measurement, the locking spring is activated to unlock the device. Under the action of spring 5, the conical sliding body moves to the left, pressing against the two probing wheels and moving radially to adhere to the inner wall of the finned tube. The elongated cylinder is then pushed to move within the finned tube. The inner diameter of the finned tube can be read from the scale line 803 on the right side of the elongated rod. This allows for the quantitative measurement of the amount of corrosion thinning on the inner wall of the finned tube. Figure 11 As shown.

[0069] When the device detects a corrosion thinning zone on the inner wall of the finned tube, the elongated cylinder is rotated to different angles to measure and record the amount of corrosion thinning in the circumferential direction of that zone.

[0070] If the detection wheel gets stuck when moving from the area of ​​maximum corrosion to the area of ​​slight corrosion on the inner wall of the finned tube, the slender cylinder can be held in place by hand while the slender rod is pulled to the right, so that the two detection wheels move closer to each other under the action of the elastic frame, reducing the radial distance and thus releasing the jam.

[0071] After the measurement is completed, hold the slender tube in place by hand and pull the slender rod to the right until the top of the locking spring is engaged in the annular groove of the slender rod. Then, pull the device out of the finned tube and proceed to measure the next finned tube.

Claims

1. A device for measuring the degree of corrosion of the inner wall of a finned tube, comprising a locking spring, an annular groove, a conical slide body, two detection wheels, two elastic frames, a slender cylinder, a spring, two copper sleeves, and a slender rod; characterized in that: The length of the slender rod is greater than the length of the slender tube, and it can be inserted into the slender tube; The left end of the slender rod is machined with a tapered sliding body connecting thread for connecting the tapered sliding body; Threads are machined into the inner holes at both ends of the slender cylinder, and the copper sleeves are installed to support and reduce the sliding resistance of the slender rod. On the slender rod, a spring is provided between the conical slide body and the copper sleeve to press the conical slide body to move it to the left, so that the two probe wheels are pressed against the inner wall of the finned tube during measurement; The device also includes a pointer and a scale line on the right side of the slender rod. The pointer is L-shaped and is fixed to the right side of the slender tube by a screw, with the tip of the pointer pointing to the scale line. The numbers on the scale line correspond to the inner diameter of the finned tube measured by the distance between the outer edges of the two probe wheels; The annular groove is located to the left of the scale line at the right end of the slender rod; The locking spring is made of a thin plate bent into shape and is fixed to the right side of the slender tube by screws. When the inner diameter of the finned tube is not measured, the top of the locking spring is stuck in the annular groove, which can prevent the slender rod from moving axially relative to the slender tube, making it easier for the device to be pulled out of the finned tube. The conical slide body is a frustum with a small cylinder at the top. Two straight slide tracks are machined on the upper and lower sides of the small cylinder, and two oblique slide tracks are machined on the upper and lower sides of the frustum. The straight slide tracks and the oblique slide tracks are aligned and connected to form the upper and lower slide tracks of the conical slide body. After being connected, the detection wheel can roll on the upper and lower slide tracks of the conical slide body. Each of the elastic frames includes an elastic plate and two lugs, the lugs being disposed at the non-fixed end of the elastic plate, and the detection wheel being mounted on the lugs via a pin. The slender cylinder is a slender steel tube with an outer diameter smaller than the inner diameter of the finned tube, which can be inserted into the finned tube during use; threaded holes are machined on the upper and lower sides of the left end of the slender cylinder for mounting two elastic brackets with screws; the two elastic brackets elastically press the two probe wheels against the slide of the conical slide body, and the inner diameter of the finned tube is measured by the distance between the outer edges of the two probe wheels.

2. The device for measuring the degree of corrosion of the inner wall of a finned tube according to claim 1, characterized in that: The ratio of the axial distance L to the radial rise distance H corresponding to the inclined slide is a fixed value R. R is set to 4:1 or 6:1, that is, the radial movement distance of the two detection wheels in the finned tube corresponds to 2 or 3 times the axial movement distance of the conical slide body, which is used to realize the magnified display of the inner diameter measurement dimension of the finned tube.

3. The device for measuring the degree of corrosion of the inner wall of a finned tube according to claim 2, characterized in that: The right end of the slender rod is machined into a spherical head for manual pushing and pulling.

4. A method for measuring the degree of corrosion on the inner wall of an air cooler finned tube, characterized in that, The device for measuring the degree of corrosion of the inner wall of the finned tube as described in any one of claims 1-3 is used, and the following steps are performed: Hold the slender cylinder in place by hand and pull the slender rod to the right until the top of the locking spring is engaged in the annular groove of the slender rod. Under the action of the elastic frame, the two detection wheels move closer to each other, reducing the radial distance. Insert the conical sliding body and one end of the probe wheel into the finned tube through the tube box inspection port of the air cooler; When the measurement begins, the locking spring is activated to unlock it. Under the action of the spring, the conical slide body moves to the left and presses against the two detection wheels, moving radially and sticking to the inner wall of the finned tube. The slender cylinder is pushed to move inside the finned tube, and the inner diameter of the finned tube is read from the scale line on the right side of the slender rod, thereby quantitatively measuring the amount of corrosion thinning of the inner wall of the finned tube. After the measurement is completed, hold the slender tube in place by hand and pull the slender rod to the right until the top of the locking spring is engaged in the annular groove of the slender rod. Then, pull the device out of the finned tube and proceed to measure the next finned tube.

5. The method for measuring the degree of corrosion on the inner wall of an air cooler finned tube according to claim 4, characterized in that, When the device detects a corrosion thinning zone on the inner wall of the finned tube, the elongated cylinder is rotated to different angles to measure and record the amount of corrosion thinning in the circumferential direction of that zone.

6. The method for measuring the degree of corrosion on the inner wall of an air cooler finned tube according to claim 5, characterized in that, If the detection wheel gets stuck when moving from the area of ​​maximum corrosion to the area of ​​slight corrosion on the inner wall of the finned tube, hold the slender cylinder by hand and pull the slender rod to the right, so that the two detection wheels move closer to each other under the action of the elastic frame, reducing the radial distance and thus releasing the jam.

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