Welding fixture for main water supply Venturi tube
By designing an integrated forging structure and special welding fixture, the problems of low structural strength and insufficient welding accuracy of the main water supply venturi pipe are solved, and efficient and accurate welding processes are achieved, ensuring the coaxiality and safety of the pipe.
Patent Information
- Application Number
- CN202421049069.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-05-14
- Publication Date
- 2024-12-27
- Estimated Expiration
- 2034-05-14
AI Technical Summary
During long-term use, the existing main hydranturi pipes are deformed due to low structural strength and oscillation, resulting in measurement deviations and safety hazards, and it is difficult to ensure the accuracy and coaxiality of the inner surface in the welding process.
A main hydrvenculi pipe structure including upstream straight pipe section, integrated forging pipe body, expansion section and downstream straight pipe section was designed, and is equipped with a special welding fixture, through positioning chuck, positioning tail frame, pipeline positioning frame and Rotate the handwheel and other structures to ensure the accuracy and coaxiality of welding.
The accuracy and efficiency of welding operations are improved, the processing technology is optimized, the internal surface processing accuracy and overall coaxiality of the main hydrant feed pipe are ensured, and the safety and service life of the structure are improved.
Smart Images
Figure CN222243424U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of clamps, in particular to a welding clamp for a main water supply Venturi tube. Background Art
[0002] The Venturi tube is a differential pressure throttling device that meets the requirements of GB / T 2624-2006 standard. The main feedwater Venturi tube is installed on the main feedwater pipeline of the nuclear power plant. The fluid flows through the Venturi tube, and the flow beam forms a local contraction at the throat of the Venturi tube, thereby increasing the flow velocity and reducing the static pressure. Thus, a static pressure difference is generated between the upstream side and the throat of the Venturi tube. According to the differential pressure and fluid characteristics, the fluid flow in the pipeline can be measured. This measurement method is based on the law of conservation of energy and the flow continuity equation.
[0003] The inventor proposes a new main water supply Venturi tube, which includes an upstream straight pipe section, an integrated forged pipe body, two expansion sections and a downstream straight pipe section. The integrated forged pipe body is axially provided with a contraction section and a throat, and the two expansion sections are welded. The downstream straight pipe section is coaxially sleeved outside the expansion section, and a cavity is formed between the two. One end of the integrated forged pipe body is welded to the upstream straight pipe section, and the other end is respectively welded to the expansion section and the downstream straight pipe section. A reinforcement ring is arranged between the expansion section and the downstream straight pipe section. In order to optimize the welding and processing technology, it is now urgently necessary to design a special welding fixture for welding processing to ensure the processing accuracy of the inner surface and the overall coaxiality. Utility Model Content
[0004] The utility model aims to overcome the shortcomings and deficiencies of the prior art and to provide a welding fixture for a main water supply venturi tube.
[0005] The technical solution adopted by the utility model is as follows: a welding fixture for a main water supply Venturi tube, comprising a base, a positioning chuck is arranged at one end of the base, and a positioning tail frame is arranged at the other end, at least three pipeline positioning frames are arranged between the positioning chuck and the positioning tail frame, the positioning chuck is fixed to the base, the positioning tail frame and the pipeline positioning frame are slidably arranged along the length direction of the base, the pipeline positioning frame comprises a moving frame and a center frame, the moving frame is provided with a first through hole and at least three positioning screws uniformly distributed along the circumference of the first through hole, the center frame is coaxially arranged on the inner circumference of the first through hole, a positioning bearing is arranged on the positioning screw near the center frame, the positioning bearing abuts against the circumferential outer wall of the center frame, a second through hole is coaxially arranged on the center frame with the first through hole, a positioning ring is arranged in the second through hole, a plurality of fixing bolts are uniformly distributed along the circumference of the positioning ring on the center frame, a third through hole adapted to the main water supply Venturi tube is arranged on the positioning ring, and the third through hole is coaxially arranged with the second through hole.
[0006] It is further configured that one end of the positioning screw away from the center frame extends out of the movable frame and is provided with a rotating hand wheel.
[0007] It is further configured that a positioning cone head is coaxially arranged on the positioning tail frame and the third through hole, the positioning cone head is rotatably arranged relative to the positioning tail frame, and the positioning cone head includes a tapered portion that can abut against the main water supply Venturi tube.
[0008] It is further configured that the pipeline positioning frame includes two center frames, and are respectively arranged coaxially with the first through hole on the front and rear sides of the positioning screw, and positioning bearings are arranged on the front and rear sides of the positioning screw close to the center frame, and the positioning bearings on the same side abut against the circumferential outer wall of the center frame.
[0009] It is further configured that the inner diameter of the second through hole is larger than the outer diameter of the positioning ring.
[0010] It is further configured that the end of the fixing bolt is provided with an arc-shaped abutting surface, and abuts against the circumferential outer wall of the positioning ring.
[0011] It is further configured that the movable frame includes a positioning portion, clamping blocks are arranged at both ends of the positioning portion, the clamping blocks are connected to the positioning portion through tightening bolts, and a positioning plate is arranged on the base along the sliding direction of the movable frame, and the positioning plate is located between the positioning portion and the clamping block.
[0012] It is further configured that the number of the pipeline positioning frames is three.
[0013] The beneficial effects of the utility model are as follows: the welding fixture of the utility model improves the accuracy and efficiency of the welding operation of the main water supply Venturi tube, optimizes the welding and processing technology, and thus ensures the processing accuracy and overall coaxiality of the inner surface of the main water supply Venturi tube. BRIEF DESCRIPTION OF THE DRAWINGS
[0014] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, without paying creative labor, other drawings obtained based on these drawings still belong to the scope of the utility model.
[0015] Figure 1 It is a schematic diagram of the utility model;
[0016] Figure 2 for Figure 1 The enlarged view of point A in the middle;
[0017] Figure 3 for Figure 1 The enlarged view of point B in the middle;
[0018] Figure 4 It is a partial schematic diagram of the utility model Figure 1 ;
[0019] Figure 5 It is a cross-sectional view of the utility model;
[0020] Figure 6 It is a partial schematic diagram of the utility model Figure 2 . DETAILED DESCRIPTION
[0021] Now the utility model is further described in detail with reference to the accompanying drawings. These drawings are simplified schematic diagrams, which only illustrate the basic structure of the utility model in a schematic manner, and therefore only show the components related to the utility model.
[0022] In the description of the present application, it should be understood that the terms "longitudinal", "radial", "length", "width", "thickness", "up", "down", "left", "right", "front", "back", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. In the description of the present application, unless otherwise specified, "plurality" means two or more.
[0023] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.
[0024] In the description of this application, it should be noted that all expressions using "first" and "second" in the embodiments of the present invention are for the purpose of distinguishing two non-identical entities with the same name or non-identical parameters. It can be seen that "first" and "second" are only for the convenience of expression and should not be understood as limitations on the embodiments of the present invention. The subsequent embodiments will not explain this one by one.
[0025] Embodiment 1:
[0026] like Figures 1 to 6As shown, a welding fixture for a main water supply venturi tube includes a base 1, one end of the base 1 is provided with a positioning chuck 2, and the other end is provided with a positioning tailstock 3. The positioning chuck 2 adopts a three-jaw chuck or a four-jaw chuck commonly used in the field of machining technology in the prior art.
[0027] Among them, since the inventors found that the existing main water supply Venturi tube structure mostly adopts a sleeve type (outer tube + Venturi inner tube) structure, the Venturi inner tube is made of steel plate rolled and welded, and the throat is made of stainless steel hose to draw pressure. During long-term use, it is found that the total length of the inner tube of the Venturi tube of this structure is usually about 2 meters, the upstream end is welded and fixed to the outer sleeve, and the downstream end is freely in contact with the outer sleeve. The middle is suspended without effective support, and the structural strength is low. Long-term use under high flow conditions will cause the inner tube to deform due to vibration. When the residual deformation exceeds the standard shape and size of the Venturi tube, measurement deviation will occur, and there will be safety hazards.
[0028] Therefore, if Figure 6 As shown, the inventor proposes a main water supply Venturi tube, which includes an upstream straight pipe section 6, an integrated forged pipe body 7, two expansion sections 8 and a downstream straight pipe section 9, wherein the integrated forged pipe body 7 is axially provided with a contraction section 71 and a throat 72, the two expansion sections 8 are welded, the downstream straight pipe section 9 is coaxially sleeved outside the expansion section 8, and a cavity is formed between the two, one end of the integrated forged pipe body 7 is welded to the upstream straight pipe section 6, and the other end is respectively welded to the expansion section 8 and the downstream straight pipe section 9, a reinforcement ring 10 is arranged between the expansion section 8 and the downstream straight pipe section 9, the main water supply Venturi tube designs the contraction section 71 and the throat 72 into an integrated forging structure, which is then welded to the upstream and downstream straight pipe sections and the diffusion section respectively, thereby simplifying the overall structure of the Venturi tube and having a higher overall structural strength, thereby improving the safety of its use.
[0029] This welding fixture is specially designed for this main water supply Venturi tube, which can improve the welding efficiency of this main water supply Venturi tube.
[0030] At least three pipe positioning frames 4 are arranged between the positioning chuck 2 and the positioning tail frame 3. In the present embodiment, there are three pipe positioning frames 4, so that welding the main water supply Venturi tube is most convenient.
[0031] The positioning chuck 2 is fixed to the base 1, and the positioning tail frame 3 and the pipe positioning frame 4 are slidably arranged along the length direction of the base 1. The structure of the sliding arrangement can refer to the structure of a lathe and will not be described in detail here. It provides good adjustability, so that the welding fixture can be suitable for pipes of different lengths and specifications, thereby enhancing its scope of application.
[0032] The pipeline positioning frame 4 includes a moving frame 41 and a center frame 42. The moving frame 41 is provided with a first through hole 43 and at least three positioning screws 44 evenly distributed along the circumference of the first through hole 43. The center frame 42 is coaxially arranged on the inner circumference of the first through hole 43. A positioning bearing 45 is arranged on the positioning screw 44 near the center frame 42. The positioning bearing 45 abuts against the circumferential outer wall of the center frame 42 to reduce damage to the surface of the workpiece and protect the surface quality of the main water supply venturi tube. The center frame 42 is coaxially provided with a second through hole 46 with the first through hole 43. The second through hole 46 is coaxially arranged with the first through hole 43. 6 is provided with a positioning ring 47, and a plurality of fixing bolts 48 are evenly distributed along the circumference of the positioning ring 47 on the center frame 42. A third through hole 49 adapted to the main water supply Venturi tube is provided on the positioning ring 47, ensuring good compatibility with Venturi tubes of different specifications. The third through hole 49 is coaxially arranged with the second through hole 46. Through the positioning ring 47 and the positioning bearing 45, the welding fixture can achieve strict coaxial alignment of the welding main water supply Venturi tube. At the same time, the main water supply Venturi tube can be freely rotated during welding for circumferential welding, which reduces the difficulty of welding and improves the efficiency of welding.
[0033] Through the above arrangement, the welding fixture improves the accuracy and efficiency of the welding operation of the main water supply Venturi tube, optimizes the welding and processing technology, and thus ensures the processing accuracy and overall coaxiality of the inner surface of the main water supply Venturi tube.
[0034] One end of the positioning screw 44 away from the center frame 42 extends out of the movable frame 41 and is provided with a rotating hand wheel 441. The rotating hand wheel 441 allows the operator to manually adjust the positioning screw 44 without additional tools, thereby simplifying the operation process.
[0035] A positioning cone head 31 is coaxially arranged on the positioning tail frame 3 with the third through hole 49. The positioning cone head 31 is rotatably arranged relative to the positioning tail frame 3. The positioning cone head 31 includes a conical portion 311 that can abut against the main water supply Venturi tube. When the conical portion 311 abuts against the main water supply Venturi tube, automatic center alignment can be achieved, and at the same time, the clamp can accommodate changes in pipe diameters within a certain range, thereby improving the adaptability and versatility of the clamp.
[0036] The pipeline positioning frame 4 includes two center frames 42, and are respectively arranged coaxially with the first through hole 43 on the front and rear sides of the positioning screw 44. The positioning screw 44 is provided with positioning bearings 45 on the front and rear sides close to the center frame 42. The positioning bearings 45 on the same side abut against the circumferential outer wall of the center frame 42, and the main water supply Venturi tube is fixed by the double-sided abutment, so that the pipeline positioning frame 4 has better balance, thereby making the coaxiality of the main water supply Venturi tube better during welding.
[0037] The inner diameter of the second through hole 46 is larger than the outer diameter of the positioning ring 47 , so that the positioning ring 47 is easier to install and there is space for adjusting the coaxiality.
[0038] The end of the fixing bolt 48 is provided with an arc-shaped abutting surface 481 , and abuts against the circumferential outer wall of the positioning ring 47 , so as to better protect the positioning ring 47 .
[0039] The movable frame 41 includes a positioning portion 411, and clamping blocks 5 are arranged at both ends of the positioning portion 411. The clamping blocks 5 are connected to the positioning portion 411 through tension bolts. A positioning plate 101 is arranged on the base 1 along the sliding direction of the movable frame 41, and the positioning plate 101 is located between the positioning portion 411 and the clamping block 5. When the tension bolts are loosened, the movable frame 41 can move freely. After the tension bolts are tightened, the movable frame 41 is fixed. Of course, the positioning structure between the movable frame 41 and the base 1 is not limited to this, and a cylinder can be used in combination with a slide rail and a slider, or a motor can be used in combination with a lead screw and a slider, etc.
[0040] The processing flow of the main water supply Venturi tube:
[0041] A1: Due to the long length of the expansion section and the tapered cross section, the processing is difficult. Considering the high manufacturing difficulty, the original long expansion section is split into two expansion sections 8 for welding, firstly rolled and welded in sections, and the reinforcement rings 10 are welded separately.
[0042] A2: Clamp the upstream section of the integrated forged pipe body 7 on the positioning chuck 2, and move a pipe positioning frame 4 to the downstream end of the integrated forged pipe body 7, use a dial indicator to adjust the coaxiality of the workpiece clamping, and then weld the first expansion section 8.
[0043] A3: Finish the reinforcement ring 10 at the downstream of the first expansion section 8, and set a pipe positioning frame 4 outside the reinforcement ring 10, use a dial indicator to adjust the coaxiality of the workpiece clamping, and then finish the inner surface of the workpiece along the processing route from upstream to downstream to ensure the dimensional accuracy, taper, roundness and surface roughness of the contraction section 71, throat 72 and the first expansion section 8, ensure the sharpness of the transition, and ensure the overall coaxiality.
[0044] A4: Weld the second expansion section 8.
[0045] A5: Finish the reinforcement ring 10 on the second expansion section 8, and set a pipe positioning frame 4 outside the reinforcement ring 10, use a dial indicator to adjust the coaxiality of the workpiece clamping, and then finish the inner surface of the workpiece from the downstream to the upstream of the second expansion section 8 to ensure the dimensional accuracy, taper and surface roughness of the conical diffusion section, ensure that the transition is smooth and step-free, and ensure the overall coaxiality.
[0046] Next, the downstream end surface of the second expansion section 8 is finely processed to ensure that the overall length meets the requirements.
[0047] Then, the pipe positioning frame 4 at the second expansion section 8 is removed, and the outer circumference at the downstream port of the second expansion section 8 and the outer circumference of the reinforcement ring 10 on the second expansion section 8 are processed to ensure the dimensional accuracy of the matching with the outer sleeve.
[0048] A6: Rough-process the upstream straight pipe section 6, reserve a certain processing allowance, and fine-process the downstream straight pipe section 9.
[0049] A7: Fit the two expansion sections 8 into the downstream straight pipe section 9, and assemble and clamp them together with the upstream straight pipe section 6 on the positioning chuck 2. Use a dial indicator to adjust to ensure the coaxiality of the assembly and clamping of each section, and weld the upstream straight pipe section 6 and the downstream straight pipe section 9.
[0050] A8: Assemble the main water supply Venturi tube as a whole on the lathe, and fine-process the inner diameter of the pipe to the weld to ensure dimensional accuracy, roundness and surface roughness, and ensure that the transition is smooth without steps.
[0051] The above disclosure is only a preferred embodiment of the present invention, and certainly cannot be used to limit the scope of rights of the present invention. Therefore, equivalent changes made according to the claims of the present invention are still within the scope covered by the present invention.
Claims
1. A welding fixture for a main water supply venturi tube, characterized in that: The invention comprises a base (1), wherein a positioning chuck (2) is arranged at one end of the base (1), and a positioning tail frame (3) is arranged at the other end, and at least three pipeline positioning frames (4) are arranged between the positioning chuck (2) and the positioning tail frame (3), wherein the positioning chuck (2) is fixed to the base (1), and the positioning tail frame (3) and the pipeline positioning frame (4) are slidably arranged along the length direction of the base (1), and the pipeline positioning frame (4) comprises a moving frame (41) and a center frame (42), wherein the moving frame (41) is provided with a first through hole (43) and at least three positioning screws (44) uniformly distributed along the circumference of the first through hole (43), and the center frame (42) is coaxial with the moving frame (41) and the center frame (42). A positioning bearing (45) is arranged on the inner circumference of the first through hole (43), and is provided on the positioning screw (44) near the center frame (42). The positioning bearing (45) abuts against the circumferential outer wall of the center frame (42). A second through hole (46) is arranged on the center frame (42) coaxially with the first through hole (43). A positioning ring (47) is arranged in the second through hole (46). A plurality of fixing bolts (48) are evenly distributed along the circumference of the positioning ring (47) on the center frame (42). A third through hole (49) adapted to the main water supply Venturi tube is arranged on the positioning ring (47), and the third through hole (49) is arranged coaxially with the second through hole (46).
2. A welding fixture for a main water supply venturi tube according to claim 1, characterized in that: One end of the positioning screw rod (44) away from the center frame (42) extends out of the movable frame (41) and is provided with a rotating hand wheel (441).
3. A welding fixture for a main water supply venturi tube according to claim 1, characterized in that: A positioning cone head (31) is coaxially arranged on the positioning tail frame (3) and the third through hole (49). The positioning cone head (31) is rotatably arranged relative to the positioning tail frame (3). The positioning cone head (31) includes a conical portion (311) that can abut against the main water supply Venturi tube.
4. A welding fixture for a main water supply venturi tube according to claim 1, characterized in that: The pipeline positioning frame (4) includes two center frames (42), which are respectively arranged coaxially with the first through hole (43) on the front and rear sides of the positioning screw (44), and the front and rear sides of the positioning screw (44) close to the center frame (42) are both provided with positioning bearings (45), and the positioning bearings (45) on the same side are in contact with the circumferential outer wall of the center frame (42).
5. The welding fixture for the main water supply venturi tube according to claim 1, characterized in that: The inner diameter of the second through hole (46) is greater than the outer diameter of the positioning ring (47).
6. A welding fixture for a main water supply venturi tube according to claim 5, characterized in that: The end of the fixing bolt (48) is provided with an arc-shaped abutting surface (481) which abuts against the circumferential outer wall of the positioning ring (47).
7. The welding fixture for the main water supply venturi tube according to claim 1, characterized in that: The movable frame (41) comprises a positioning portion (411), and clamping blocks (5) are arranged at both ends of the positioning portion (411). The clamping blocks (5) are connected to the positioning portion (411) via loose bolts. A positioning plate (101) is arranged on the base (1) along the sliding direction of the movable frame (41), and the positioning plate (101) is located between the positioning portion (411) and the clamping blocks (5).
8. The welding fixture for the main water supply venturi tube according to claim 1, characterized in that: There are three pipeline positioning frames (4).