CN114523270A - Welding processing method for CCT framework of groove-lacking type bent oblique solenoid - Google Patents

Abstract

The invention discloses a method for welding and assembling a CCT skeleton of a groove-shaped curved oblique solenoid. The skeleton is divided into several sections in the axial direction, and each section is divided into half in the radial direction for processing. Several curved semi-cylinders are processed on the upper surface, the inner diameter of the curved semi-cylinder and the required bending radian of each section, the contact surface positioning dovetail groove, and the trapezoidal notch is milled on the radial contact surface of the curved semi-cylinder, that is, the two semi-curved CCT skeleton diameters Connect the missing part of the wire groove to the assembly welding place; then the two upper and lower curved semi-cylinders in the radial direction are positioned by dovetail grooves for dislocation assembly, and electron beam welding is used to reinforce the groove formed by the gap, and several curved cylinders pass through the dovetail groove. Positioning, axial cold fitting method dislocation assembly and splicing into a complete curved semi-cylinder; then according to the required outer diameter of the skeleton, the outer wall of the curved cylinder is processed; finally, the inclined helical grooves are processed on the outer walls of the two curved semi-cylinders. In the present invention, the skeleton is processed and assembled in the manner of radial halving and axial slicing, so as to reduce the processing difficulty of the curved CCT skeleton.

Description

A method for welding and assembling a CCT skeleton of a slotted curved oblique solenoid

technical field

The invention mainly relates to the technical field of processing and manufacturing special-shaped superconducting magnet skeletons, and in particular relates to a processing and preparation method of a curved oblique solenoid (Canted Cosine Theta, CCT) magnet skeleton.

Background technique

The curved CCT coil structure is a new type of magnet structure that has been studied in recent years. The CCT coil has the advantages of light and novel coil structure, superior magnetic field quality, no accumulated stress in the CCT magnet coil, no need to optimize the coil end, and outstanding mechanical properties. And it is suitable for various existing practical superconducting wires. At the same time, the structure can also be used to design a combined functional magnet, which has a good application prospect in the fields of large scientific engineering, people's livelihood medical treatment and the like.

The CCT coil bobbin is a slotted bobbin, and the processing quality of the bobbin directly affects the magnetic field quality of the magnet. Due to the particularity of the structure of the curved CCT bobbin, the existing processing methods are not suitable for the processing of the curved CCT magnet bobbin, which also restricts Development of curved CCT magnet technology.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a processing and preparation method suitable for bending CCT magnet coil bobbins.

In order to achieve the above object, the technical scheme adopted in the present invention is:

A method for welding and assembling a CCT skeleton of a groove-shaped curved oblique solenoid, comprising the following steps:

Step 1: If a plurality of curved semi-cylinders are milled out by a combination of rough machining and fine machining on the aluminum alloy material, each upper and lower curved semi-cylinder is a pair, and the plurality of curved semi-cylinders need to be processed again before finishing. Perform annealing and stress relief treatment;

Step 2: Milling a pair of dovetail grooves and a welding notch on the upper and lower curved semi-cylindrical contact surfaces as a pair, wherein the welding notch is two trapezoidal cross-sections milled perpendicular to the outer diameter surface to the inner diameter direction. The bottom of the notch is tangent to the bottom surface of the helical groove, and the notch extends along the axial direction of the curved semi-cylinder to form a groove, leaving a certain welding space for the electron beam welding of the upper and lower curved semi-cylinders; The semi-cylinders are positioned by dovetail grooves, and are assembled together by dislocation in the axial direction. Electron beam welding is performed at the trapezoidal notch, and the upper and lower semi-cylinders are assembled and welded to form a complete dislocation curved cylinder after welding;

Step 3: According to step 2, process and assemble multiple sections of dislocation curved cylinders. The contact surface of each section of the dislocation curved cylinder is machined with dovetail grooves that can be matched, and they are respectively assembled into dislocation curved cylinders, and the multi-section curved cylinders are used in the axial direction. The dovetail groove is positioned and assembled and spliced by the cold fitting method to form a complete curved CCT skeleton cylinder;

Step 4: finish machining the outer wall surface of the complete CCT cylindrical frame, and mill out the bending outer diameter r _o required for the bending of the CCT frame;

Step 5: Use the five-axis CNC machine tool to continuously process the helical groove on the outer wall of the complete CCT cylinder, and use the curved oblique helical curve equation as the driving trajectory.

Further, the upper and lower half-ring parts are respectively used to fix the upper and lower half skeletons for welding, wherein the upper half-ring part adjusts the height of the upper half of the skeleton; the upper and lower circular plates are used to match the upper half-circle The ring parts fix the overall structure; the bolts are used to connect and support the upper and lower semicircular plates, and can move up and down to adjust the overall structure.

Further, according to the bending radius and outer diameter of the curved CCT skeleton to be processed, a rectangular aluminum alloy block material is selected, and the rectangular aluminum alloy block material is subjected to annealing and stress relief treatment.

Further, in step 2, radial up-down assembly is performed, and axial dislocation assembly is adopted.

Further, in step 3, the curved cylinder is assembled and spliced by the cold fitting method for axis splicing. One section of the curved cylinder needs to be immersed in liquid nitrogen to cool down, and then spliced and assembled with a section of the curved cylinder at room temperature.

Further, in step 5, no helical grooves are processed on the groove-deficient part.

Further, the trajectory equation of the wire slot is optimized, adjusted and changed according to the magnetic field quality requirements.

Further, after the processed skeleton is subjected to a series of treatment tests, coil preparation work such as winding is carried out; the skeleton of the curved CCT magnet needs to be formed by nesting the inner and outer two layers of skeleton, and the second layer of skeleton is processed with reference to the above method. , in which in step 2, the dislocation direction of the inner skeleton of the first layer can be opposite to the dislocation direction of the inner frame of the first layer.

The beneficial effects of the present invention are:

1. The processing method adopts the processing of the curved CCT skeleton in half and axial sections along the radial direction, and can process the curved skeleton with a certain diameter according to the actual demand, which not only reduces the processing difficulty, but also saves materials and reduces costs;

2. There are dovetail grooves that can be matched on the contact surface of the curved semi-cylinder and the contact surface of the curved cylindrical segment, which can quickly find the fitting position during assembly and splicing;

3. The dislocation assembly method is adopted in the upper and lower radial directions of the curved semi-cylindrical cylinder, which enhances the mechanical properties of the skeleton and makes the structure firmer. It can also directly process the spiral groove in the dislocation part of the skeleton, reducing the weight of the skeleton;

4. A wire slot gap is reserved at the electron beam welding position of the two curved semi-cylindrical assemblies, and the two semi-circular curved CCT skeletons are firmly welded together by electron beam welding at the notch position of the curved CCT skeleton to enhance the mechanical properties of the skeleton. strength.

The invention has good innovation and strong practicability, and can effectively solve the problems that the current curved CCT skeleton is difficult to process and the multi-layer nesting of the curved CCT magnets. Multi-pole magnet skeleton and magnet fabrication have important reference significance.

Description of drawings

In order to illustrate the embodiments of the present invention or the existing technical solutions more clearly, the following briefly introduces the accompanying drawings that need to be used in the description of the embodiments or the existing technology. Obviously, the accompanying drawings in the following description are only the For the embodiments of the invention, for those of ordinary skill in the art, other drawings can also be obtained according to the provided drawings without any creative effort.

Figure 1 is a schematic diagram of a curved oblique helix.

FIG. 2 is a schematic diagram of the upper half of the curved semi-cylinder in the present invention.

Figure 3 is a schematic diagram of the lower half of the curved semi-cylinder in the present invention.

FIG. 4 is a schematic diagram of the upper and lower assembly of two curved semi-cylinders in the present invention.

FIG. 5 is a schematic diagram of a section of the assembled and welded curved cylinder and an enlarged schematic diagram of a splicing part in the present invention.

FIG. 6 is a schematic diagram of axial assembly and splicing of a curved cylinder in the present invention.

FIG. 7 is a schematic diagram of the completed assembly and splicing of the curved semi-cylindrical according to the present invention.

FIG. 8 is a schematic diagram of the grooved curved CCT skeleton in the present invention.

Detailed ways

The embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. It should be understood that the descriptions and illustrations of the embodiments of the present invention are essentially used for illustration rather than limiting the present invention.

The present invention will be further described below by taking the curved oblique spiral CCT diode magnet skeleton as an example. The trajectory of the curved CCT skeleton wire groove can be determined according to the trajectory equation of the curved oblique helix. Taking the curved CCT diode magnet skeleton as an example, the trajectory 1 of a specific curved oblique helical coil established according to the line slot trajectory equation is shown in Figure 1. The curved CCT skeleton is divided into 5 sections along the axial direction, and each section is divided into two semi-curved skeletons along the radial direction. The schematic diagrams of the upper and lower semi-curved skeletons of each section are shown in Figures 2 and 3. The processing method steps are as follows. Show:

Step 1: According to the bending radius and outer diameter of a certain curved CCT skeleton to be processed, select a suitable rectangular aluminum alloy block material, and perform annealing and stress relief treatment on the rectangular aluminum alloy block material. A number of curved semi-cylinders, such as the upper semi-cylinder 201 and the lower semi-cylinder 301, are milled out by a combination of rough machining and fine machining. As shown in Figures 2 and 3, the bending arc and inner diameter _ri It should meet the requirements of the curved CCT skeleton, and the outer diameter _ro of the curved semi-cylinder is slightly larger than the outer diameter of the CCT skeleton by 2-5mm. The two curved semi-cylinders need to be annealed and stress-relieved again before finishing.

Step 2: Milling out the matable dovetail grooves and welding notch 4 as shown in 401 in Figure 2 and 402 in Figure 3 respectively on the two contact surfaces of the two curved semi-cylinders, as shown in Figure 4. The welding notch 4 is a notch with two trapezoidal cross-sections milled perpendicular to the outer diameter surface to the inner diameter direction, and the bottom of the notch is tangent to the bottom surface of the helical groove (ie, the inner diameter of the coil). The notch extends along the axial direction, leaving a certain welding space for electron beam welding of the upper and lower curved semi-cylinders. The upper and lower curved semi-cylinders 201 and 301 are positioned using dovetail grooves and assembled together in an axial dislocation, as shown in FIG. 4 , and electron beam welding is performed at the trapezoidal notch, and the upper and lower semi-cylinders are assembled and welded. , after welding, a complete curved semi-cylinder is formed as shown in Figure 5. The upper and lower dislocation welding can make the overall structure of the skeleton after the axial welding assembly stronger, and the dislocation part can still process the spiral groove.

Step 3: Process and assemble 5 dislocated curved cylinders according to step 2. The contact surface of each dislocation curved cylinder can be matched with dovetail grooves, such as the upper half-cylinder 201, 202, 203, 204, 205, and the lower half-cylinder 301 , 302, 303, 304, and 305, respectively, are paired and assembled into dislocation curved cylinders. As shown in Figure 6, the 5-segment curved cylinder is positioned by the dovetail groove in the axial direction, and assembled and spliced by the cold fitting method to form a complete curved CCT skeleton cylinder as shown in Figure 7. The overall upper semicircle Cylinder 2 (including multi-stage upper semi-cylinders 201, 202, 203, 204, 205), and integral lower semi-cylinder 3 (including multi-stage lower semi-cylinders 301, 302, 303, 304, 305). The upper and lower half-ring parts 6 and 5 in Figures 4 and 6 are respectively used to fix the upper and lower half frame for welding, wherein the upper half-ring member 6 can adjust the height of the upper half frame. The upper and lower circular plates 7 and 8 are used to cooperate with the upper half-circle member 6 to fix the overall structure. The bolts 9 are used to connect and support the upper and lower half-circular plates 7 and 8, and can move up and down to adjust the overall structure.

Step 4: finish machining the outer wall surface of the complete CCT cylindrical frame, and mill out the bending outer diameter r _o required for the bending of the CCT frame;

Step 5: Use the five-axis CNC machine tool to continuously process the helical groove on the outer wall of the complete CCT cylinder, and use the curved oblique helical curve equation as the driving trajectory. 8, 10 in FIG. 8 is a helical groove, and 11 in FIG. 8 is a grooved part.

CCT dipole magnets generally require two layers of inner and outer skeleton coils to be nested. The second layer of skeleton nested outside the first layer of skeleton is processed with reference to the above-mentioned method. The dislocation direction of the first layer endoskeleton is opposite. After the processed skeleton is subjected to a series of treatment tests, the coil winding, joint production, epoxy impregnation, magnet assembly, etc. can be used to complete the production of the magnet. .

The above is only a specific embodiment of the present invention, and the specific embodiment is to better explain the principle and practical application of the present invention, but the protection scope of the present invention is not limited to this, any technology familiar with the technical field Personnel can easily think of changes or substitutions within the technical scope disclosed in the present invention, and any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention are all included in the claims of the present invention. within the scope of protection.

Claims (8)

1. A CCT framework welding processing method of a slot-lacking type bent oblique solenoid is characterized by comprising the following steps:

the method comprises the following steps: milling a plurality of bent semi-circular cylinders on an aluminum alloy material in a mode of combining rough machining and fine machining, wherein every two bent semi-circular cylinders are used as a pair, and annealing stress removal treatment is needed to be carried out on the plurality of bent semi-circular cylinders again before fine machining;

step two: a dovetail groove and a welding notch which can be matched are respectively milled on the contact surfaces of the upper and lower curved semi-cylinders which are taken as a pair, wherein the welding notch is two notches with trapezoidal sections which are milled towards the inner diameter direction and are vertical to the outer diameter surface, the bottom of the notch is tangent to the bottom surface of the spiral line groove, the notch extends along the axial direction of the curved semi-cylinders to form a notch, and a certain welding space is reserved for the electron beam welding of the upper and lower curved semi-cylinders; the upper and lower two curved semi-cylinders are positioned by utilizing dovetail grooves and are assembled together in a staggered mode in the axial direction, electron beam welding is carried out at the trapezoidal notch, the upper and lower two semi-cylinders are assembled and welded, and a section of complete staggered curved cylinder is formed after welding;

step three: processing and assembling a plurality of sections of staggered bent cylinders according to the second step, processing a matched dovetail groove on the contact surface of each section of staggered bent cylinder, respectively matching and assembling the staggered bent cylinders, positioning the plurality of sections of bent cylinders by using the dovetail grooves in the axial direction, and assembling and splicing the staggered bent cylinders by a cold matching method to form a complete bent CCT framework cylinder;

step four: finish machining is carried out on the outer wall surface of the complete CCT cylinder framework, and the bending outer diameter r required by the bending CCT framework is milled_o；

Step five: and continuously processing a spiral wire groove on the outer wall surface of the complete CCT cylinder by using a five-axis numerical control machine tool, and taking a curved oblique spiral curve equation as a driving track.

2. The CCT framework welding processing method of the slot-lacking type bending inclined solenoid coil as claimed in claim 1, further comprising:

the upper semi-ring component and the lower semi-ring component are respectively used for fixing the upper framework and the lower framework and welding, wherein the upper semi-ring component adjusts the height of the upper framework; the upper circular plate and the lower circular plate are used for being matched with the upper semicircular ring component to fix the whole structure; the bolt is used for connecting and supporting the upper semicircular plate and the lower semicircular plate and can move up and down to adjust the whole structure.

3. The CCT framework welding processing method of the slot-lacking type bending inclined solenoid coil as claimed in claim 1, further comprising:

according to the bending radius and the outer diameter of the CCT skeleton to be bent, rectangular aluminum alloy block materials are selected and are subjected to annealing stress removal treatment.

4. The CCT framework welding processing method of the slot-lacking type bending inclined solenoid coil as claimed in claim 1, further comprising:

and in the second step, radial up-and-down assembly is carried out, and a staggered assembly mode is adopted in the axial direction.

5. The CCT framework welding processing method for the slot-lacking type bending inclined solenoid according to claim 1, characterized by further comprising the following steps:

and the bent cylinders in the third step are assembled and spliced in an axis splicing manner by adopting a cold distribution method, wherein one section of the bent cylinder needs to be soaked in liquid nitrogen for cooling, and then is assembled and spliced with one section of the bent cylinder at the normal temperature.

6. The CCT framework welding processing method of the slot-lacking type bending inclined solenoid coil as claimed in claim 1, further comprising:

and in the fifth step, the spiral wire grooves are not processed at the groove-lacking part.

7. The CCT framework welding processing method of the slot-lacking type bending inclined solenoid coil as claimed in claim 1, further comprising:

and the track equation of the wire grooves is optimized, adjusted and changed according to the magnetic field quality requirement.

8. The CCT framework welding processing method of the slot-lacking type bending inclined solenoid coil as claimed in claim 1, further comprising:

after a series of treatment tests are carried out on the processed framework, coil preparation work such as winding and the like is carried out; and the framework of the bent CCT magnet is formed by nesting and combining an inner framework and an outer framework, the second-layer framework is processed according to the method, and when the second-layer framework is welded in a staggered mode in the radial direction, the staggered direction of the second-layer framework is opposite to that of the first-layer inner framework.

Images