Ultrasonic detection bracket for corrosion condition of tube wall of heat exchanger tube bundle and its use method

Abstract

The present invention discloses an ultrasonic detection bracket for the corrosion condition of the tube wall of a heat exchanger tube bundle and a method for using the bracket. The bracket includes a catheter, a clamping frame and a fixed base; the clamping frame clamps and fixes the catheter by a clamping block, a clamping angle steel and a fastening screw; the fixed base is connected to the clamping frame by a limit screw, and the three sliders are respectively adjusted in spacing by a long bolt and two positioning screws, and three positioning claws are arranged on the bottom surfaces of the three sliders. The method adjusts the spacing of the three sliders so that the three positioning claws are inserted into and fixed in three adjacent heat exchange tubes of the inspected heat exchanger, adjusts the catheter to the tube mouth of the inspected heat exchange tube and aligns it, inserts the centering frame installed with an ultrasonic sensor from the upper part of the catheter and extends it into the far end of the inspected heat exchange tube to start detection, and slowly and uniformly pulls the centering frame out of the catheter until it is removed from the catheter to complete the ultrasonic detection. The bracket and the method for using the bracket effectively solve the problem of blind spots in detection, make a complete diagnosis of the corrosion condition of the tube wall of the heat exchanger tube bundle, and eliminate safety hazards during use.

Description

Technical Field

[0001] The invention relates to the field of detection technology, and in particular to an ultrasonic detection bracket for corrosion conditions of tube walls of a heat exchanger tube bundle and a use method thereof. Background Art

[0002] Usually, the corrosion condition of the tube wall of the ferromagnetic heat exchanger tube bundle is detected and evaluated by rotating ultrasonic technology. During on-site detection, the ultrasonic sensor is installed on the top of the centering frame, and the ultrasonic sensor and the centering frame are extended to the far end of the heat exchange tube, and then the corrosion condition detection is started from the far end of the heat exchange tube to the inlet end of the tube wall. During this period, the two sets of support arms of the centering frame simultaneously support the ultrasonic sensor well in each heat exchange tube being detected and move at a uniform speed. Only the ultrasonic sensor at its top that rotates at a high speed can receive reliable echo signals; therefore, in the area about 200mm close to the tube sheet, due to the centering support problem and the disturbance of the coupled water flow, the signal is distorted and there is no wall thickness measurement value. This area is usually a detection blind area, and this pipe section is also a key area for the joint action of stress and corrosion for the heat exchanger. The existence of this detection blind area reduces the integrity of the basic data for the quality and safety status evaluation of the heat exchanger.

[0003] At present, the application of rotary ultrasonic testing in the corrosion condition of the tube bundle wall of the heat exchanger has the problem of blind spot detection, which makes it impossible to make a complete diagnosis of the corrosion condition of the tube bundle wall of the heat exchanger, and thus there are certain safety hazards. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a bracket and a method for using the ultrasonic detection of the corrosion condition of the tube bundle wall of a heat exchanger. The bracket and the method for using the bracket overcome the defects of the ultrasonic detection of the corrosion condition of the tube bundle wall of the heat exchanger, effectively solve the problem of blind spots in detection, make a complete diagnosis of the corrosion condition of the tube bundle wall of the heat exchanger, and eliminate safety hazards during use.

[0005] In order to solve the above technical problems, the ultrasonic detection bracket for corrosion condition of tube bundle wall of heat exchanger of the present invention comprises a guide tube, a clamping frame and a fixed base;

[0006] The clamping frame comprises a clamping block, a clamping angle steel and a fastening screw, the bottom surface of the clamping block is provided with a limiting long groove, one side of the clamping angle steel is provided on one side of the clamping block, the fastening bolt is screwed on the other side of the clamping angle steel, and the conduit is vertically provided between the end surface of the clamping block and the other side of the clamping angle steel and is fixed by the fastening screw;

[0007] The fixed base includes a bottom plate, a first end plate, a second end plate, a first slider, a second slider, a third slider, a limit screw, a long bolt, two positioning screws and three positioning claws, the first end plate and the second end plate are respectively vertically arranged at two ends of the bottom plate, the limit screw is inserted into the limit long groove on the bottom surface of the clamping block and then screwed on the surface of the bottom plate, the bottom surface of the bottom plate is arranged on a slide, the first slider is located in the slide and moves along the slide, the long bolt is screwed on the first end plate and the front end is movably connected to the first slider, the second end plate is provided with a horizontal positioning groove, the two positioning screws are respectively inserted into the horizontal positioning groove and then screwed on the second slider and the third slider, and the three positioning claws are respectively vertically arranged on the bottom surfaces of the first slider, the second slider and the third slider.

[0008] Furthermore, the end surface of the clamping block and the other side of the clamping angle steel are respectively provided with arc surfaces for clamping the conduit.

[0009] Furthermore, a process waist-shaped groove is provided on the top surface of the clamping block extending to the limiting long groove.

[0010] A method for using the above detection bracket comprises the following steps:

[0011] Step 1: Select the size of the conduit according to the specifications of the heat exchanger tube bundle to be inspected, fix the conduit between the clamping block and the other side of the clamping angle steel and fix it with the fastening screws;

[0012] Step 2: Use the long bolt and two positioning screws to adjust the distances between the first slider, the second slider and the third slider respectively, so that the three positioning claws are respectively inserted into the three adjacent heat exchange tubes of the heat exchanger to be inspected, and then tighten the long bolt and the two positioning screws to fix the three positioning claws;

[0013] Step 3: Move and rotate the clamping frame with the limit screws connecting the clamping frame and the fixed base as the center, so that the conduit is aligned with the heat exchange tube to be inspected, and the two tube openings are close to each other, and tighten the limit screws to fix the position of the clamping frame;

[0014] Step 4: Insert the centering frame equipped with the ultrasonic sensor from the upper part of the conduit, pass through the conduit, and then extend it to the far end of the heat exchange tube to be tested to start testing;

[0015] Step 5: Slowly and evenly pull the centering frame out of the tube until the centering frame moves out of the tube, completing the ultrasonic inspection of the heat exchange tube under inspection.

[0016] Since the ultrasonic detection bracket and use method of the corrosion condition of the tube wall of the heat exchanger bundle of the present invention adopts the above technical scheme, that is, the bracket includes a catheter, a clamping frame and a fixed base; the clamping frame clamps and fixes the catheter through a clamping block, a clamping angle steel and a fastening screw; the fixed base is connected to the clamping frame through a limit screw and the clamping frame moves and rotates along the bottom plate, and the three sliders are respectively adjusted in spacing by long bolts and two positioning screws, and three positioning claws are arranged on the bottom surfaces of the three sliders. The method first selects the catheter size according to the specifications of the inspected heat exchanger bundle and fixes it through the clamping frame, adjusts the spacing of the three sliders so that the three positioning claws are inserted into the three adjacent heat exchange tubes of the inspected heat exchanger and fixed, adjusts the catheter to the tube mouth of the inspected heat exchange tube and aligns it, inserts the centering frame installed with an ultrasonic sensor from the upper part of the catheter, passes through the catheter and extends into the far end of the inspected heat exchange tube to start detection, and slowly and uniformly pulls the centering frame out of the catheter until the centering frame moves out of the catheter, and completes the ultrasonic detection of the inspected heat exchange tube. The bracket and the use method overcome the defects of ultrasonic detection of the corrosion condition of the tube wall of the heat exchanger tube bundle, effectively solve the problem of blind area of ​​detection, make a complete diagnosis of the corrosion condition of the tube wall of the heat exchanger tube bundle, and eliminate the potential safety hazards in use. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The present invention is further described in detail below in conjunction with the accompanying drawings and embodiments:

[0018] Figure 1 It is a schematic diagram of the structure of the ultrasonic detection bracket for the corrosion condition of the tube wall of the heat exchanger tube bundle of the present invention. DETAILED DESCRIPTION

[0019] Implementation example Figure 1 As shown, the ultrasonic detection bracket for corrosion condition of tube wall of heat exchanger tube bundle of the present invention comprises a guide tube 1, a clamping frame 2 and a fixed base 3;

[0020] The clamping frame 2 includes a clamping block 21, a clamping angle steel 22 and a fastening screw 23. The bottom surface of the clamping block 21 is provided with a limiting long groove 24. One side of the clamping angle steel 22 is provided on one side of the clamping block 21. The fastening screw 23 is screwed on the other side of the clamping angle steel 22. The catheter 1 is vertically provided between the end surface of the clamping block 21 and the other side of the clamping angle steel 22 and is fixed by the fastening screw 23.

[0021] The fixed base 3 includes a bottom plate 31, a first end plate 32, a second end plate 33, a first slider 34, a second slider 35, a third slider 36, a limit screw 37, a long bolt 38, two positioning screws 39 and three positioning claws 40. The first end plate 32 and the second end plate 33 are respectively vertically arranged at both ends of the bottom plate 31, the limit screw 37 penetrates into the limit long groove 24 on the bottom surface of the clamping block 21 and is screwed on the surface of the bottom plate 31, the bottom surface of the bottom plate 31 is provided on the slideway 41, the first slider 34 is located in the slideway 41 and moves along the slideway 41, the long bolt 38 is screwed on the first end plate 32 and the front end is movably connected to the first slider 34, the second end plate 33 is provided with a horizontal positioning groove 42, the two positioning screws 39 respectively penetrate into the horizontal positioning groove 42 and are screwed on the second slider 35 and the third slider 36, and the three positioning claws 40 are respectively vertically arranged on the bottom surfaces of the first slider 34, the second slider 35 and the third slider 36.

[0022] Preferably, the end surface of the clamping block 21 and the other side of the clamping angle steel 22 are respectively provided with arcuate surfaces 25, 26 for clamping the conduit 1; the arcuate surfaces match the surface of the conduit for easy clamping.

[0023] Preferably, a process waist-shaped groove 27 is provided on the top surface of the clamping block 21 extending to the limiting long groove 24; the process waist-shaped groove can facilitate the tightening or loosening operation of the limiting screw.

[0024] A method for using the above detection bracket comprises the following steps:

[0025] Step 1: Select the size of the conduit according to the specifications of the heat exchanger tube bundle to be inspected, fix the conduit between the clamping block and the other side of the clamping angle steel and fix it with the fastening screws;

[0026] Step 2: Use the long bolt and two positioning screws to adjust the distances between the first slider, the second slider and the third slider respectively, so that the three positioning claws are respectively inserted into the three adjacent heat exchange tubes of the heat exchanger to be inspected, and then tighten the long bolt and the two positioning screws to fix the three positioning claws;

[0027] Step 3: Move and rotate the clamping frame with the limit screws connecting the clamping frame and the fixed base as the center, so that the conduit is aligned with the heat exchange tube to be inspected, and the two tube openings are close to each other, and tighten the limit screws to fix the position of the clamping frame;

[0028] Step 4: Insert the centering frame equipped with the ultrasonic sensor from the upper part of the conduit, pass through the conduit, and then extend it to the far end of the heat exchange tube to be tested to start testing;

[0029] Step 5: Slowly and evenly pull the centering frame out of the tube until the centering frame moves out of the tube, completing the ultrasonic inspection of the heat exchange tube under inspection.

[0030] Usually in ultrasonic testing, since the centering frame for fixing the sensor has a length of more than 200 mm, and the sensor can only obtain an effective detection signal when the centering frame is stably supported on the inner wall of the pipe, the use of the catheter of this bracket, that is, the extension tube, is equivalent to extending the length of the heat exchanger tube bundle, so that the sensor can be moved to the vicinity of the pipe mouth and can also be well centered and stably supported, so as to achieve good water coupling and ultrasonic signal transmission and reception. Without this bracket, good coupling and effective signal reception cannot be achieved.

[0031] This bracket and method effectively solve the problem that when the tube sheet heat exchanger uses rotary ultrasound to detect the corrosion of the tube bundle, there is a large detection blind spot in the pipe section close to the tube sheet. The catheter in this bracket can realize 360-degree rotation and positioning with a variable rotation radius, and the three-point support spacing of the fixed base is fully adjustable, so it is suitable for fixing and supporting the catheter on tube sheets of different specifications, so that the catheter can be easily aligned with the heat exchange tube to be inspected. The catheter can be made of stainless steel pipe, and the inner diameter size of the steel pipe matches the applicable range of the centering frame; based on the change in the relative position of the clamping frame and the fixed base, the most suitable inspection station can be optimized to implement the inspection, so that the heat exchange tubes at all positions of the tube sheet heat exchanger can meet the goal of reducing the detection blind spot; and the bracket has a simple structure, convenient adjustment, simple detection operation, easy to carry, convenient on-site operation, and improves the efficiency of ultrasonic detection operations.

Claims

1. A support for ultrasonic detection of corrosion conditions of tube walls of heat exchanger tube bundles, characterized in that: The support comprises a catheter, a clamping frame and a fixed base; The clamping frame comprises a clamping block, a clamping angle steel and a fastening screw, the bottom surface of the clamping block is provided with a limiting long groove, one side of the clamping angle steel is provided on one side of the clamping block, the fastening screw is screwed on the other side of the clamping angle steel, and the conduit is vertically provided between the end surface of the clamping block and the other side of the clamping angle steel and is fixed by the fastening screw; The fixing base comprises a bottom plate, a first end plate, a second end plate, a first slider, a second slider, a third slider, a limiting screw, a long bolt, two positioning screws and three positioning claws, wherein the first end plate and the second end plate are respectively vertically arranged at two ends of the bottom plate, the limiting screws penetrate into the limiting long groove on the bottom surface of the clamping block and are screwed on the surface of the bottom plate, the bottom surface of the bottom plate is arranged on a slideway, the first slider is located in the slideway and moves along the slideway, the long bolt is screwed on the first end plate and the front end is movably connected to the first slider, the second end plate is provided with a horizontal positioning groove, the two positioning screws respectively penetrate into the horizontal positioning groove and are screwed on the second slider and the third slider, and the three positioning claws are respectively vertically arranged on the bottom surfaces of the first slider, the second slider and the third slider; The end surface of the clamping block and the other side of the clamping angle steel are respectively provided with arc-shaped surfaces for clamping the conduit; The top surface of the clamping block extends to the limiting long groove and is provided with a process waist-shaped groove.

2. A method for using the detection bracket according to claim 1, characterized in that This method comprises the following steps: Step 1: Select the size of the conduit according to the specifications of the heat exchanger tube bundle to be inspected, fix the conduit between the clamping block and the other side of the clamping angle steel and fix it with the fastening screws; Step 2: Use the long bolt and two positioning screws to adjust the distances between the first slider, the second slider and the third slider respectively, so that the three positioning claws are respectively inserted into the three adjacent heat exchange tubes of the heat exchanger to be inspected, and then tighten the long bolt and the two positioning screws to fix the three positioning claws; Step 3: Move and rotate the clamping frame with the limit screws connecting the clamping frame and the fixed base as the center, so that the conduit is aligned with the heat exchange tube to be inspected, and the two tube openings are close to each other, and tighten the limit screws to fix the position of the clamping frame; Step 4: Insert the centering frame equipped with the ultrasonic sensor from the upper part of the conduit, pass through the conduit, and then extend it to the far end of the heat exchange tube to be tested to start testing; Step 5: Slowly and evenly pull the centering frame out of the tube until the centering frame moves out of the tube, completing the ultrasonic inspection of the heat exchange tube under inspection.

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