A clamping device for testing the pull-off force of expanded connection between a heat exchange tube and a tube sheet

Abstract

The utility model discloses a kind of chuck devices of heat exchange pipe and tube plate expansion joint connection pull-off force test, including simulation tube plate, the inside expansion joint of simulation tube plate has heat exchange pipe, the inside left end of heat exchange pipe is inserted with load exerting core rod, still include top clamping mechanism;Top clamping mechanism: it includes outer taper thread pull rod, inner taper elastic expansion sleeve and hollow taper outer sleeve, the inside right end of heat exchange pipe is inserted with outer taper thread pull rod, the outside sleeve of outer taper thread pull rod is connected with inner taper elastic expansion sleeve and hollow taper outer sleeve, the chuck device of heat exchange pipe and tube plate expansion joint connection pull-off force test, adopt chuck design, through bevel extrusion radial expansion force, to firmly fix heat exchange pipe and pull-off force test stress element together, improve the one-time success rate of heat exchange pipe and tube plate expansion joint connection pull-off force test in heat exchange equipment, reduce test cost, substantially improve test efficiency, ensure that the accurate, reliable, efficient of test data.

Description

Technical Field

[0001] This utility model relates to the field of mechanical manufacturing technology, specifically a clamping device for testing the pull-out force of the expansion joint between a heat exchange tube and a tube sheet. Background Technology

[0002] The purpose of expanding the heat exchange tubes to the tube sheet in heat exchange equipment is twofold: firstly, to eliminate the gap between the heat exchange tubes and the tube sheet bores (to prevent gap corrosion during operation); and secondly, to withstand a certain axial force to ensure the safe and stable operation of the equipment. Therefore, the magnitude of the pull-out force directly determines the service life of the heat exchange equipment and the economic benefits for the enterprise. Currently, some connection devices for testing the pull-out force of expanded heat exchange tubes to tube sheets use a method of welding the base plate to the inner wall of the heat exchange tube, with the tube sheet expanded to the outside of the heat exchange tube. The tube sheet is then fixed using a pull-out force testing device. Simultaneously, axial pressure is applied to the base plate. When the base plate causes the heat exchange tube to expand and separate from the tube sheet, the pull-out force between the tube sheet and the heat exchange tube can be measured. However, since the base plate and the heat exchange tube are connected by welding, especially when the wall thickness of the heat exchange tube is thin, the quality of the weld is often difficult to guarantee. When performing the pull-out force test, the weld between the base plate and the heat exchange tube often breaks first, causing the pull-out force test to fail normally. It is necessary to repeat the test many times, which is time-consuming and laborious, and the measurement data is unstable. Therefore, we propose a clamp device for pull-out force test of the expansion connection between the heat exchange tube and the tube sheet. Utility Model Content

[0003] The technical problem to be solved by this utility model is to overcome the existing defects and provide a clamping device for pull-out force test of heat exchange tube and tube sheet expansion connection. The device adopts a clamping design and uses the radial expansion force squeezed by the inclined plane to firmly fix the heat exchange tube and the force-bearing element of the pull-out force test together, thereby improving the one-time success rate of the pull-out force test of heat exchange tube and tube sheet expansion connection in heat exchange equipment, reducing test costs, greatly improving test efficiency, and ensuring the accuracy, reliability and efficiency of test data. It can effectively solve the problems in the background technology.

[0004] To achieve the above objectives, the present invention provides the following technical solution: a clamping device for pull-out force test of heat exchange tube and tube sheet expansion connection, including a simulated tube sheet, wherein a heat exchange tube is expanded inside the simulated tube sheet, and a load application mandrel is inserted into the left end of the heat exchange tube, and a top clamping mechanism is also included.

[0005] Top clamping mechanism: It includes an external tapered threaded tie rod, an internal tapered elastic expansion sleeve, and a hollow tapered outer sleeve. The external tapered threaded tie rod is inserted into the right end of the heat exchange tube. The external tapered threaded tie rod is sleeved with the internal tapered elastic expansion sleeve and the hollow tapered outer sleeve. This device adopts a clamp design, which uses the radial expansion force squeezed by the inclined plane to firmly fix the heat exchange tube and the force-bearing element of the pull-out force test together. This improves the one-time success rate of the pull-out force test of the heat exchange tube and tube sheet expansion connection in the heat exchange equipment, reduces the test cost, greatly improves the test efficiency, and ensures the accuracy, reliability and efficiency of the test data.

[0006] Furthermore, the top clamping mechanism also includes a top clamping nut, which is threaded into the threaded groove at the right end of the outer side of the external tapered threaded tie rod, so that the hollow conical sleeve in the clamping device for the pull-out force test of the heat exchange tube and the tube sheet expansion connection moves to the left along the body of the external tapered threaded tie rod.

[0007] Furthermore, the top clamping mechanism also includes a chamfer, which is formed at the left end of the outer arc surface of the external tapered threaded rod. By forming the chamfer, a beveled extrusion is applied to the inner edge of the left end of the internal tapered elastic expansion sleeve.

[0008] Furthermore, the top clamping mechanism also includes a second chamfer, which is located at the left edge of the inner arc wall of the inner conical elastic expansion sleeve. The component force generated by the pressure on the inclined surface facilitates the subsequent radial expansion of the left end of the inner conical elastic expansion sleeve under pressure.

[0009] Furthermore, the top clamping mechanism also includes a chamfer three, which is formed on the left edge of the outer arc surface of the hollow cone sleeve. By forming the chamfer, a beveled extrusion is applied to the inner edge of the right end of the inner cone elastic expansion sleeve.

[0010] Furthermore, the top clamping mechanism also includes a chamfer four, which is formed at the right edge of the inner arc wall of the inner conical elastic expansion sleeve. The chamfer four is formed at the right edge of the inner conical elastic expansion sleeve, and the component force generated by the pressure on the inclined surface facilitates the subsequent radial expansion of the inner conical elastic expansion sleeve under pressure on the right end.

[0011] Furthermore, a reinforcing ring is movably sleeved on the outer side of the heat exchange tube, which limits the expansion and deformation of the outer side of the radially expanded and compressed part of the inner arc wall of the heat exchange tube in the clamping device for the pull-out force test of the heat exchange tube and the tube sheet.

[0012] Compared with the prior art, the beneficial effects of this utility model are as follows: The clamping device for the pull-out force test of the heat exchange tube and tube sheet expansion connection has the following advantages:

[0013] When using the clamp device for pull-out force test of heat exchange tube and tube sheet expansion connection, the device uses the clamp design of the top clamping mechanism to utilize the radial expansion generated by the inner conical elastic expansion sleeve due to the pressure of the inclined surface, thereby firmly fixing the heat exchange tube and the force-bearing element of the pull-out force test together, improving the one-time success rate of the pull-out force test of heat exchange tube and tube sheet expansion connection in heat exchange equipment, eliminating the need to use the welding method between the heat exchange tube and the base plate, reducing test costs, greatly improving test efficiency, and ensuring the accuracy, reliability and efficiency of test data. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the structure of this utility model;

[0015] Figure 2 This is a schematic diagram of the assembly structure of this utility model;

[0016] Figure 3 This is a structural schematic diagram showing the assembly cross-section of this utility model;

[0017] Figure 4 This is an enlarged structural diagram of point A in this utility model.

[0018] In the figure: 1. Simulated tube sheet, 2. Heat exchange tube, 3. Reinforcing ring, 4. Top clamping mechanism, 41. External tapered threaded tie rod, 42. Internal tapered elastic expansion sleeve, 43. Hollow tapered outer sleeve, 44. Tightening nut, 45. Chamfer 1, 46. Chamfer 2, 47. Chamfer 3, 48. Chamfer 4, 5. Load application mandrel. Detailed Implementation

[0019] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0020] Please see Figure 1-4 This embodiment provides a technical solution: a clamping device for pull-out force test of heat exchange tube and tube sheet expansion connection, including a simulated tube sheet 1, a heat exchange tube 2 is expanded inside the simulated tube sheet 1, a load application mandrel 5 is inserted into the left end of the heat exchange tube 2, the operator assembles the simulated tube sheet 1 and the heat exchange tube 2 according to the design document requirements, and expands the simulated tube sheet 1 and the heat exchange tube 2 through an external hydraulic expansion machine. Expansion refers to using a tube expander to expand and fix the tube body to the tube sheet according to the characteristic of metal plastic deformation. Expansion refers to expansion installation. It also includes a top clamping mechanism 4.

[0021] Top clamping mechanism 4: It includes an external tapered threaded rod 41, an internal tapered elastic expansion sleeve 42, and a hollow tapered outer sleeve 43. The external tapered threaded rod 41 is inserted into the right end of the heat exchange tube 2. The external tapered threaded rod 41 is sleeved with the internal tapered elastic expansion sleeve 42 and the hollow tapered outer sleeve 43. Top clamping mechanism 4 also includes a chamfer 45, which is located on the left end of the outer arc surface of the external tapered threaded rod 41. Top clamping mechanism 4 also includes a chamfer 46, which is located at the left edge of the inner arc wall of the internal tapered elastic expansion sleeve 42. Top clamping mechanism 4 also includes a chamfer 47, which is located at the left edge of the outer arc surface of the hollow tapered outer sleeve 43. Top clamping mechanism 4 also includes a chamfer 48, which is located at the left edge of the outer arc surface of the hollow tapered outer sleeve 43. Angle 48 is located at the right edge of the inner arc wall of the inner conical elastic expansion sleeve 42. A reinforcing ring 3 is movably fitted onto the outer side of the heat exchange tube 2. The operator fits the reinforcing ring 3 onto the right end of the outer arc surface of the heat exchange tube 2. Then, the operator sequentially fits the inner conical elastic expansion sleeve 42 and the hollow conical outer sleeve 43 onto the outer arc surface of the outer conical threaded tie rod 41 from right to left. The assembly is then inserted into the right end of the heat exchange tube 2 from right to left, so that the outer conical threaded tie rod 41 is approximately horizontally aligned with the reinforcing ring 3. As the hollow conical outer sleeve 43 moves to the left along the body of the outer conical threaded tie rod 41, the chamfered surfaces between chamfered angle 3 47 and chamfered angle 48 press against each other, causing the inner conical elastic expansion sleeve 42 to move along the inner arc surface of the heat exchange tube 2. As the outer tapered thread tie rod 41 slides synchronously to the left, chamfer 46 and chamfer 45 of the outer tapered thread tie rod 41 come into contact with each other. With the outer tapered thread tie rod 41, inner tapered elastic expansion sleeve 42, and hollow tapered outer sleeve 43 coming into contact with each other, and as the hollow tapered outer sleeve continues to move to the left along the outer tapered thread tie rod 41, the inner tapered elastic expansion sleeve 42 expands radially due to the chamfered surfaces between chamfer 46 and chamfer 45, and between chamfer 47 and chamfer 48. This tightly presses the heat exchange tube 2 at this position between the inner tapered elastic expansion sleeve 42 and the reinforcing ring 3, achieving a pull-out force for the expansion connection between the heat exchange tube 2 and the tube sheet. During the test, the heat exchange tube 2 is clamped and fixed. Then, the staff places this component on the support of the test platform, inserts the load application mandrel 5 into the left end of the heat exchange tube 2 and applies axial pressure to the left end of the load application mandrel 5, and measures the axial force at this time. The pull-out force data of the expansion connection between the heat exchange tube 2 and the tube sheet can be obtained. The device adopts a clamp design and uses the radial expansion force squeezed by the inclined plane to firmly fix the heat exchange tube 2 and the force-bearing element of the pull-out force test together. This improves the one-time success rate of the pull-out force test of the expansion connection between the heat exchange tube 2 and the tube sheet in the heat exchange equipment, reduces the test cost, greatly improves the test efficiency, and ensures the accuracy, reliability and efficiency of the test data.

[0022] The clamping mechanism 4 also includes a clamping nut 44, which is threaded into a threaded groove on the right side of the outer tapered threaded rod 41. The operator connects the clamping nut 44 from right to left into the threaded groove of the outer tapered threaded rod 41. As the clamping nut 44 moves to the left along the threaded groove, the left side of the clamping nut 44 presses against the right side of the hollow tapered sleeve 43 and drives the hollow tapered sleeve 43 to move to the left along the rod of the outer tapered threaded rod 41. As the outer tapered threaded rod 41, the inner tapered elastic expansion sleeve 42 and the hollow tapered sleeve 43 press against each other, the operator uses an external wrench to fix the outer tapered threaded rod 41 to prevent axial rotation while continuing to rotate the clamping nut 44, so that the clamping nut 44 continues to apply pressure to the hollow tapered sleeve 43.

[0023] The working principle of the clamp device for pull-out force test of heat exchange tube and tube sheet expansion connection provided by this utility model is as follows: The operator attaches the reinforcing ring 3 to the right end of the outer arc surface of the heat exchange tube 2. Then, the operator attaches the inner conical elastic expansion sleeve 42 and the hollow conical outer sleeve 43 from right to left to the outer arc surface of the outer conical threaded tie rod 41. Then, the operator inserts the assembly into the inner right end of the heat exchange tube 2 from right to left, so that the outer conical threaded tie rod 41 is approximately horizontally aligned with the reinforcing ring 3. Then, the operator connects the tightening nut 44 from right to left to the thread groove of the outer conical threaded tie rod 41. As the tightening nut 44 moves to the left along the thread groove, the left side of the tightening nut 44 presses against the right side of the hollow conical outer sleeve 43 and drives the hollow conical outer sleeve 43 to move to the left along the rod of the outer conical threaded tie rod 41. During the leftward movement of the hollow conical outer sleeve 43, the inner conical elastic expansion sleeve 42 moves to the left along the rod of the outer conical threaded tie rod 41 through the pressing contact between the chamfered surfaces of chamfered corner 3 47 and chamfered corner 48. The left slide is made so that chamfer 46 of the external tapered thread tie rod 41 is pressed into contact with chamfer 45. Then, the operator uses an external wrench to fix the external tapered thread tie rod 41 to prevent axial rotation while continuing to rotate the tightening nut 44. The tightening nut 44 continues to apply compressive force to the hollow tapered outer sleeve 43. At this time, through the chamfered surface pressing contact between chamfer 46 and chamfer 45, and the chamfered surface pressing contact between chamfer 3 and chamfer 48, the inner tapered elastic expansion sleeve 42 is radially expanded. This tightly presses the heat exchange tube 2 between the inner tapered elastic expansion sleeve 42 and the reinforcing ring 3, thus achieving the clamping and fixing of the heat exchange tube 2 during the pull-out force test of the expansion connection between the heat exchange tube 2 and the tube sheet. Then, the operator places this part of the component on the support of the test platform, inserts the load applying mandrel 5 into the left end of the heat exchange tube 2 and applies axial pressure to the left end of the load applying mandrel 5, and measures the axial force at this time to obtain the pull-out force data of the expansion connection between the heat exchange tube 2 and the tube sheet.

[0024] The above description is merely an embodiment of this utility model and does not limit the patent scope of this utility model. Any equivalent structural or procedural transformations made based on the content of this utility model specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this utility model.

Claims

1. A clamping device for a pull-out force test of a heat exchange tube and a tube sheet expansion connection, comprising a simulated tube sheet (1), wherein a heat exchange tube (2) is expanded inside the simulated tube sheet (1), and a load-applying mandrel (5) is inserted into the left end of the heat exchange tube (2), characterized in that: It also includes a top clamping mechanism (4); Top clamping mechanism (4): It includes an external tapered threaded rod (41), an internal tapered elastic expansion sleeve (42) and a hollow tapered outer sleeve (43). The external tapered threaded rod (41) is inserted into the right end of the heat exchange tube (2). The external tapered threaded rod (41) is sleeved with the internal tapered elastic expansion sleeve (42) and the hollow tapered outer sleeve (43).

2. The clamping device for pull-out force test of heat exchange tube and tube sheet expansion connection according to claim 1, characterized in that: The top clamping mechanism (4) also includes a top clamping nut (44), which is threadedly connected to the threaded groove opened at the right end of the outer tapered threaded rod (41).

3. The clamping device for pull-out force test of heat exchange tube and tube sheet expansion connection according to claim 1, characterized in that: The top clamping mechanism (4) also includes a chamfer (45), which is located at the left end of the outer arc surface of the external tapered threaded tie rod (41).

4. The clamping device for pull-out force test of heat exchange tube and tube sheet expansion connection according to claim 1, characterized in that: The top clamping mechanism (4) also includes a second chamfer (46), which is located at the left edge of the inner arc wall of the inner conical elastic expansion sleeve (42).

5. The clamping device for pull-out force test of heat exchange tube and tube sheet expansion connection according to claim 1, characterized in that: The top clamping mechanism (4) also includes a chamfer three (47), which is located on the left edge of the outer arc surface of the hollow cone outer sleeve (43).

6. The clamping device for pull-out force test of heat exchange tube and tube sheet expansion connection according to claim 1, characterized in that: The top clamping mechanism (4) also includes a chamfer four (48), which is located at the right edge of the inner arc wall of the inner conical elastic expansion sleeve (42).

7. The clamping device for pull-out force test of heat exchange tube and tube sheet expansion connection according to claim 1, characterized in that: The heat exchange tube (2) is movably fitted with a reinforcing ring (3).

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