CN115038203A

CN115038203A - Electromagnetic inductor for induction heating

Info

Publication number: CN115038203A
Application number: CN202210831611.5A
Authority: CN
Inventors: 谭昊; 王汉杰; 李云学
Original assignee: Yantai Tiancheng Machinery Co ltd
Current assignee: Yantai Tiancheng Machinery Co ltd
Priority date: 2022-07-14
Filing date: 2022-07-14
Publication date: 2022-09-09

Abstract

The invention relates to the technical field of electromagnetic induction heating, and discloses an electromagnetic inductor for induction heating, which is used for induction heating of a workpiece, wherein a region to be processed of the workpiece is divided into a plurality of heating regions which are adjacent to each other according to shape mutation positions; the magnetizer is U-shaped and surrounds the outer side of the conductor, the widths of two side plates of the magnetizer are Y1 and Y2 respectively, the width of a top plate of the magnetizer is Y3, Y3 is more than or equal to Y1, and Y3 is more than or equal to Y2; on the premise that the thickness of each magnetizer is the same, the size parameter of the magnetizer is defined as Y1+ Y2+ Y3; the magnetizers are superposed and combined to form magnetizer groups, one heating area corresponds to one magnetizer group, and the size parameters of the magnetizers in the adjacent magnetizer groups are different. The size of the magnetizer is changed according to the structure of the workpiece, and the heating effect on different positions of the workpiece is improved.

Description

Electromagnetic inductor for induction heating

Technical Field

The invention relates to the technical field of electromagnetic inductors, in particular to an electromagnetic inductor suitable for induction heating.

Background

The induction quenching is to heat the workpiece by utilizing eddy current generated in the workpiece by electromagnetic induction, and has the advantages of small deformation of the processed workpiece, less oxidation and decarbonization in the heat treatment process, high production efficiency, mechanized or automatic realization of the process, energy conservation, environmental protection and the like. The surface of a workpiece subjected to induction quenching usually has residual pressure stress, and because the induction quenching has a skin effect, the austenitizing temperature of the workpiece subjected to induction quenching is better than that of the workpiece subjected to resistance furnace quenching, and the high degree of superheat ensures that the complete austenitizing degree is larger and the surface hardness is higher, so that the service life of the part is prolonged.

However, the existing induction quenching technology has certain limitations, and one of the most critical factors influencing induction heating is the design of an inductor, particularly for some products with special structures, the traditional inductor design can cause the heating effect at the position of a hole, a groove or a sudden change in geometric shape to be poor, and some parts even have no way of effectively heating the sudden change position, so that the products need to be continuously subjected to integral quenching or carburization at present, and the application of induction quenching is limited.

Therefore, there is a need for an electromagnetic inductor that can ensure effective heating of abrupt change positions of parts.

Disclosure of Invention

The invention provides an electromagnetic inductor for induction heating, aiming at the technical problems in the prior art.

The technical scheme for solving the technical problems is as follows: an electromagnetic inductor for induction heating is used for induction heating of a workpiece, a to-be-processed area of the workpiece is divided into a plurality of heating areas which are adjacent to each other according to shape mutation positions, the electromagnetic inductor comprises a conductor and a magnetizer, the conductor is used for transmitting an alternating electric field, and the magnetizer is used for conducting an alternating magnetic field to the to-be-heated workpiece;

the magnetizer is U-shaped, the magnetizer surrounds the outer side of the conductor, the widths of two side plates of the magnetizer are Y1 and Y2 respectively, the width of a top plate of the magnetizer is Y3, Y3 is more than or equal to Y1, and Y3 is more than or equal to Y2; on the premise that the thickness of each magnetizer is the same, the size parameter of the magnetizer is defined as Y1+ Y2+ Y3;

and a plurality of magnetizers are superposed and combined to form a magnetizer group, one heating area corresponds to one magnetizer group, and the size parameters of the magnetizers in the adjacent magnetizer groups are different.

On the basis of the technical scheme, the magnetic induction intensity of the corresponding position of the workpiece is adjusted by changing the size parameters of the magnetizer, and uniform heat treatment processing of mutation positions such as grooves, holes and the like on the workpiece is realized.

In order to achieve the convenience of use and the stability of the equipment, the following improvements can be made to the technical scheme:

further, be applicable to the work piece that is equipped with the plane rectangular channel that the degree of depth is D1 on the face that awaits processing, wherein D1<3mm, uses plane rectangular channel as the border on the work piece, is divided into two and waits to heat the district, specifically: the plane rectangular groove is set as a first heating area to be heated, and a second heating area to be heated is arranged outside the plane rectangular groove;

the electromagnetic inductor is provided with a first magnetizer group and a second magnetizer group, the first magnetizer group is matched with the first heating area to be heated, and the second magnetizer group is matched with the second heating area to be heated;

setting:

the size parameter a of the magnetizer in the first magnetizer group is Y1+ Y2+ Y3;

the size parameter b of the magnetizer in the second magnetizer group is Y1 ' + Y2 ' + Y3 ';

then a equals b +1.5 × D1.

Furthermore, the width dimension Y1 of the magnetizer in the first magnetizer group is not more than 6.5mm, Y2 is not more than 6.5mm, and Y3 is not more than 6.5 mm.

Further, the width dimension Y1 ' of the magnetizer in the second magnetizer group is less than or equal to 5.5mm, Y2 ' is less than or equal to 5.5mm, and Y3 ' is less than or equal to 5.5 mm.

Further, the difference value of any two of the width sizes Y1, Y2 and Y3 of the magnetizers in the first magnetizer group is less than or equal to 1.5 mm.

The machining method is further suitable for workpieces with corner grooves on surfaces to be machined, each corner groove comprises a groove wall I and a groove wall II which are arranged in an included angle mode, an arc-shaped groove with the cross section being the radius R is arranged at the intersection of the groove wall I and the groove wall II, R is smaller than 12mm, the depth of the arc-shaped groove in the direction perpendicular to the groove wall I is D2, D2 is smaller than 3mm, the depth of the arc-shaped groove in the direction perpendicular to the groove wall II is D3, and D3 is smaller than 2 mm; the workpiece is divided into two to-be-heated areas, namely a corner area and a non-corner area by taking a corner as a boundary;

the electromagnetic inductor is L-shaped and matched with the workpiece, a first magnetizer group and a second magnetizer group are arranged on the electromagnetic inductor, the first magnetizer group is matched with the corner area, and the second magnetizer group is matched with the non-corner area;

and a ═ b + R/2+ D2+2 × D3.

Further, the first magnetizer group covers the same length L in the first and second slot walls, and the length L is 3 × R + D2+ D3.

The invention has the beneficial effects that: according to the structure of the workpiece, the size of the magnetizer on the induction coil is changed, and when alternating current passes through the induction coil, different magnetic fluxes are generated at different positions of the inductor, so that the heating effect on different positions of the workpiece is improved, the quality of the heat treatment process of the workpiece is improved, the use of induction heating on different workpieces is promoted, the application range of induction heating is improved, the energy is saved, the environment is protected, and the energy consumption is reduced.

Drawings

FIG. 1 is a schematic structural diagram of an electromagnetic inductor according to the present invention;

FIG. 2 is a schematic cross-sectional view of example 1 of the present invention;

FIG. 3 is a diagram illustrating the effect of heat treatment of a planar rectangular groove workpiece by a conventional process;

FIG. 4 is a graph showing the effect of heat treatment on a flat rectangular groove workpiece by using the embodiment 1;

FIG. 5 is a schematic cross-sectional view of example 2 of the present invention;

FIG. 6 is a schematic diagram of the effect of heat treatment of a right-angle groove workpiece by a conventional process;

FIG. 7 is a graph showing the effect of heat treatment on a right-angled groove workpiece by using the scheme of example 2.

The reference numbers are recorded as follows: 1. a conductor; 2. a magnetizer; 3. and (5) a workpiece.

Detailed Description

The principles and features of this invention are described below in conjunction with the following drawings, which are set forth by way of illustration only and are not intended to limit the scope of the invention.

The invention discloses an electromagnetic inductor for induction heating, which is used for induction heating of a workpiece 3, wherein a region to be processed of the workpiece 3 is divided into a plurality of heating regions which are adjacent to each other according to shape mutation positions, the electromagnetic inductor comprises a conductor 1 and a magnetizer 2, the conductor 1 is used for transmitting an alternating electric field, and the magnetizer 2 is used for transmitting an alternating magnetic field to the workpiece 3 to be heated;

the magnetizer 2 is U-shaped, the magnetizer 2 encircles in the outside of conductor 1, the width of two curb plates of magnetizer 2 is Y1 and Y2 respectively, the width of 2 roof of magnetizer is Y3, during the use, refer to that fig. 2 shows, in the magnetic line of force got into work piece 3 by two curb plates of magnetizer 2, all magnetic lines of force all need pass through the roof of magnetizer 2, consequently, the size of the width Y3 of roof is greater than Y1 and Y2, can avoid magnetizer 2 because of generating heat seriously and take place the condition of burning out, guarantee this electromagnetic inductor's life. On the premise that the thickness of each magnetizer 2 is the same, the size parameters of the magnetizer 2 are defined as Y1+ Y2+ Y3; a plurality of the magnetizers 2 are superposed and combined to form a magnetizer group, one heating area corresponds to one magnetizer group, and the size parameters of the magnetizers 2 in the adjacent magnetizer groups are different.

Example 1:

referring to fig. 1 to 4, in the present embodiment, an inductor suitable for a workpiece 3 having a planar rectangular groove with a depth of D1 on a surface to be processed is provided, the conductor 1 is an induction coil, specifically a copper induction coil, and the magnetizer 2 is formed by stacking a plurality of silicon steel sheets.

In this example, the depth D1 of the planar rectangular groove is 2mm, and the workpiece 3 is bounded by the planar rectangular groove and is divided into two areas to be heated, specifically: the planar rectangular groove is set as a first to-be-heated area, see area a in fig. 2, and a second to-be-heated area, see area B and area C in fig. 2 (both area B and area C belong to the second to-be-heated area);

setting:

the size parameter a of the magnetizer 2 in the first magnetizer group is Y1+ Y2+ Y3 is 5mm +5mm +6mm is 16 mm;

the size parameter b of the magnetizer 2 in the second magnetizer group is Y1 ' + Y2 ' + Y3 ' ═ 4mm +4mm +5 mm-13 mm;

a. b satisfies the following formula:

a＝b+1.5×D1。

therefore, based on the above formula, after setting the size parameter of the magnetizer 2 in the first magnetizer group, or the size parameter of the magnetizer 2 in the second magnetizer group and determining the depth D of the planar rectangular groove, the size parameter of the magnetizer in another magnetizer group can be reversely deduced.

The difference value of any two of the width sizes Y1, Y2 and Y3 of the magnetizers 2 in the first magnetizer group is less than or equal to 1.5mm, and the closer the difference value is, the better the magnetic induction lines are, thereby ensuring that the magnetic flux of the magnetic induction lines passing through the inside of the magnetizers 2 is consistent as much as possible, ensuring that the magnetizers 2 normally heat, and avoiding the condition of local overheating.

For example, in this embodiment, the depth D1 of the planar rectangular slot on the known workpiece 3 is 2mm, the size parameters of the magnetizer 2 in the second magnetizer group are Y1 ═ 4mm, Y2 ═ 4mm, Y3 ═ 5mm, and b ═ Y1 ═ Y2 ═ Y3 ═ 13 is calculated;

according to a, b +1.5 XD 1, the a is 16 mm;

the difference between any two width dimensions Y1, Y2 and Y3 of the magnetizer 2 in the first magnetizer group is less than or equal to 1.5mm, and when the width dimensions Y3 are greater than or equal to Y1 and Y2, Y1 is less than or equal to 5mm, Y2 is less than or equal to 5mm, and Y3 is less than or equal to 6mm, of course, Y1 may be 4.5mm, Y2 may be 5.5mm, and Y3 may be 6mm, and a may be 16 mm.

According to the structure of the workpiece 3, the invention changes the magnetic flux of the magnetizer 2 at different positions on the inductor, thereby completing the heating homogenization of the workpiece 3 and ensuring the heating effect of the sudden change position of the workpiece 3, and FIG. 3 is a heat treatment effect diagram of the workpiece with a plane rectangular groove by adopting the traditional process; FIG. 4 is a graph showing the effect of heat treatment on a flat rectangular groove workpiece by using the embodiment 1; therefore, when the traditional process is used for processing a plane rectangular groove workpiece, the thickness of the processing layer at the position of the plane rectangular groove is insufficient, and the position of the non-plane rectangular groove is not uniform. The heat treatment layer is more uniform by adopting the scheme of the embodiment. And can satisfy the sclerosis layer demand of groove structure department on the work piece 3, can also have residual compressive stress on the surface of work piece 3 in addition, can improve the quality and the life of product, promoted the using widely of electromagnetic induction heating on special-shaped work piece 3.

Specific example 2

Referring to fig. 5 to 7, the workpiece 3 to be processed in this example is a workpiece with right-angled grooves.

The invention discloses a workpiece 3 with a corner groove on a surface to be machined, wherein the corner groove comprises a groove wall I and a groove wall II which are arranged at an included angle, an arc-shaped groove with a cross section of a radius R is arranged at the intersection of the groove wall I and the groove wall II, R is less than 12mm, the depth of the arc-shaped groove in the direction vertical to the groove wall I is D2, D2 is less than 3mm, the depth of the arc-shaped groove in the direction vertical to the groove wall II is D3, and D3 is less than 2 mm; the workpiece 3 is divided into two regions to be heated, namely a corner region and a non-corner region, by taking a corner as a boundary; wherein the corner regions refer to regions D in fig. 5 and the non-corner regions refer to regions E in fig. 5.

The electromagnetic inductor is L-shaped and matched with the workpiece 3, a first magnetizer group and a second magnetizer group are arranged on the electromagnetic inductor, the first magnetizer group is matched with the corner area, and the second magnetizer group is matched with the non-corner area;

the size parameter a of the magnetizer 2 in the first magnetizer group is Y1+ Y2+ Y3;

the size parameter b of the magnetizer 2 in the second magnetizer group is Y1 ' + Y2 ' + Y3 ';

and a ═ b + R/2+ D2+2 × D3.

In this embodiment, the corner groove includes a first groove wall and a second groove wall that are arranged at a right angle, a radius R of the arc-shaped groove is 8mm, a depth D2 is 1mm, and a depth D3 is 0.5mm, where a width of the magnetic conductor 2 in the first magnetic conductor group is Y1-6 mm, Y2-5 mm, Y3-6 mm, and a-17 mm.

From a + b + R/2+ D2+2 × D3, b is calculated to be 11mm, and the width dimension of the magnetic conductor 2 in the second magnetic conductor group may be Y1 'to 4mm, Y2' to 3mm, Y3 'to 4mm, or Y1' to 3mm, Y2 'to 4mm, and Y3' to 4 mm.

The first magnetizer group has the same length L in the first and second slot walls, and the length L is 3 xR + D2+ D3. In the present embodiment, the length L is 3 × 8+1+0.5 mm, 25.5 mm.

According to the actual structure of the groove type workpiece 3, the size of the magnetizer 2 on the conductor 1 is changed, so that different magnetic fluxes are generated at different positions of the electromagnet, as shown in fig. 6 and 7, the electromagnetic inductor can obviously improve the heat treatment effect at the corner groove of the workpiece 3 (wherein the area of the hatching represents the depth of the heat treatment layer of the workpiece 3), obviously, the depth of the heat treatment layer of the workpiece processed by the scheme shown in fig. 7 is more uniform, so that the corner groove obtains compressive stress, the heat treatment process quality of the workpiece 3 is improved, the fatigue life of parts is particularly prolonged, and the popularization and the use of induction heating and electromagnetic induction heating on the special-shaped workpiece 3 are promoted.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.

Claims

1. An electromagnetic inductor for induction heating, which is used for induction heating of a workpiece (3), wherein a region to be processed of the workpiece (3) is divided into a plurality of heating regions adjacent to each other according to shape mutation positions, and is characterized in that the electromagnetic inductor comprises a conductor (1) and a magnetizer (2), wherein the conductor (1) is used for transmitting an alternating electric field, and the magnetizer (2) is used for transmitting an alternating magnetic field into the workpiece (3) to be heated;

the magnetizer (2) is U-shaped, the magnetizer (2) surrounds the outer side of the conductor (1), the widths of two side plates of the magnetizer (2) are Y1 and Y2 respectively, the width of a top plate of the magnetizer (2) is Y3, Y3 is more than or equal to Y1, and Y3 is more than or equal to Y2; on the premise that the thickness of each magnetizer (2) is the same, the size parameters of the magnetizers (2) are defined as Y1+ Y2+ Y3;

the magnetizers (2) are superposed and combined to form a magnetizer group, one heating area corresponds to one magnetizer group, and the size parameters of the magnetizers (2) in the adjacent magnetizer groups are different.

2. The electromagnetic inductor according to claim 1, characterized in that it is suitable for workpieces (3) provided with a plane rectangular groove with a depth D1 on the surface to be processed, wherein D1<3mm, the plane rectangular groove on the workpiece (3) being delimited and divided into two areas to be heated, in particular: the planar rectangular groove is set as a first to-be-heated area, and a second to-be-heated area is arranged outside the planar rectangular groove;

the electromagnetic inductor is provided with a first magnetizer group and a second magnetizer group, the first magnetizer group is matched with the first zone to be heated, and the second magnetizer group is matched with the second zone to be heated;

setting:

the size parameter a of the magnetizer (2) in the first magnetizer group is Y1+ Y2+ Y3;

the size parameter b of the magnetizer (2) in the second magnetizer group is Y1 ' + Y2 ' + Y3 ';

then a equals b +1.5 × D1.

3. The electromagnetic inductor according to claim 2, characterized in that the width dimensions of the magnetizers (2) of the first magnetizer group are Y1 ≦ 6.5mm, Y2 ≦ 6.5mm, and Y3 ≦ 6.5 mm.

4. The electromagnetic inductor according to claim 3, characterized in that the width dimensions of the magnetizers (2) of the second magnetizer group are Y1 ' being ≦ 5.5mm, Y2 ' being ≦ 5.5mm, Y3 ' being ≦ 5.5 mm.

5. The electromagnetic inductor according to claim 1, 2 or 3, characterized in that the difference between any two of the width dimensions Y1, Y2, Y3 of the magnetizers (2) in the first magnetizer group is less than or equal to 1.5 mm.

6. The electromagnetic inductor according to claim 1, characterized in that the electromagnetic inductor is suitable for a workpiece (3) provided with a corner groove on a surface to be processed, the corner groove comprises a groove wall I and a groove wall II which are arranged in an included angle manner, an arc-shaped groove with a radius R in the cross section is arranged at the intersection of the groove wall I and the groove wall II, R is less than 12mm, the depth of the arc-shaped groove in the direction vertical to the groove wall I is D2, D2 is less than 3mm, the depth of the arc-shaped groove in the direction vertical to the groove wall II is D3, and D3 is less than 2 mm; the workpiece (3) is divided into two regions to be heated, namely a corner region and a non-corner region, with the corner as a boundary;

the electromagnetic inductor is L-shaped and matched with the workpiece (3), a first magnetizer group and a second magnetizer group are arranged on the electromagnetic inductor, the first magnetizer group is matched with the corner area, and the second magnetizer group is matched with the non-corner area;

and a ═ b + R/2+ D2+2 × D3.

7. The electromagnetic inductor of claim 6, wherein the first set of magnetic conductors covers the same length L in the first and second slot walls directions, and the length L is 3 XR + D2+ D3.