Main bearing ring quenching inductor and induction quenching method

Abstract

The invention provides a main bearing ring quenching inductor and an induction quenching method, and belongs to the technical field of heading machine main bearing heat treatment. Comprising an inductor body, a cold-rolled oriented silicon steel sheet and an induction ferrule, the inductor body comprises a first quenching part, a second quenching part, a heating coil and a connecting part which are connected in sequence; the cold-rolled oriented silicon steel sheet sleeves the two second quenching parts at the same time and is used for performing induction quenching on the raceway of the main bearing ring; the induction sleeve is arranged on the first quenching part in a sleeving mode and used for conducting induction quenching on the flange of the main bearing sleeve ring. By arranging the first quenching part and the second quenching part, synchronous induction quenching is carried out on the flange and the raceway of the main bearing ring at the same time, so that the heating effect of the end part of the inductor is improved, the depth uniformity of a hardening layer at the end part is optimized, the risk of quenching cracks is reduced, and the service life of the bearing is prolonged. And through synchronous induction quenching, quenching and tempering only need one time, so that the quenching and tempering time is saved, the production efficiency is improved, and the loss of manpower and material resources is reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of heat treatment of main bearings of roadheaders, and particularly relates to a quenching inductor for a main bearing race and an induction quenching method. Background Art

[0002] As a core component of a shield machine, once the main bearing is put into use, it cannot be replaced midway. Therefore, there are quite high requirements for its load-bearing reliability and service life. The raceways and ribs of the main bearing need to be quenched. The depth of the hardened layer and its uniformity directly affect the service performance of the raceways and ribs of the main bearing, such as affecting its contact fatigue strength, etc. Therefore, when quenching, ensuring the uniformity of the depth of the hardened layer on the quenched surface has extremely important value and significance. At present, when heating with a single-sided inductor, there is uneven thickness of the hardened layer near the rib, that is, the end presents a dagger-like morphology, and quenching cracks are prone to appear at the oil groove. This not only has a high production risk but also seriously affects the service life of the main bearing. Summary of the Invention

[0003] To solve the deficiencies in the prior art, the invention provides an inductor and an induction quenching method that can synchronously quench the raceways and ribs of the main bearing race, so as to effectively improve the uniformity of the depth of the hardened layer and reduce the risk of crack occurrence.

[0004] The invention provides a quenching inductor for a main bearing race, which includes an inductor body, cold-rolled grain-oriented silicon steel sheets, and an induction ring;

[0005] The inductor body includes a first quenching part, a second quenching part, a heating coil, and a connecting part connected in sequence;

[0006] The cold-rolled grain-oriented silicon steel sheets are simultaneously sleeved on two second quenching parts for induction quenching of the raceways of the main bearing race;

[0007] The induction ring is sleeved on the first quenching part for induction quenching of the ribs of the main bearing race.

[0008] Further, the first quenching part is arranged in an n-shaped structure. Both ends of the first quenching part are connected with second quenching parts, and after both ends of the first quenching part are connected with the second quenching parts, an L-shaped structure is formed;

[0009] The heating coil is connected with one of the second quenching parts;

[0010] The connecting part includes a first connecting plate and a second connecting plate arranged at intervals. One end of the first connecting plate is connected with an external heating element, and the other end of the first connecting plate is connected with the heating coil; one end of the second connecting plate is connected with the external heating element, and the other end of the second connecting plate is connected with the other second quenching part.

[0011] Furthermore, the heating coil is arranged as a hollow copper square tube structural member.

[0012] Furthermore, the cold-rolled grain-oriented silicon steel sheet is arranged as a high magnetic permeability grain-oriented silicon steel sheet.

[0013] Furthermore, a plurality of copper retaining plates for fixing the silicon steel sheets are arranged on the second quenching part at intervals, and the cold-rolled grain-oriented silicon steel sheet is sleeved on the plurality of copper retaining plates for fixing the silicon steel sheets.

[0014] The present invention also provides a method for induction quenching of a main bearing race, comprising the following steps:

[0015] Two main bearing race quenching inductors as described above are arranged in parallel, and are respectively defined as a preheating inductor A and a heating inductor B;

[0016] A coupling gap of 2 - 5 mm is provided between the rib of the main bearing race and the first quenching part in the preheating inductor A and the heating inductor B, and a coupling gap of 1.5 - 4 mm is provided between the raceway of the main bearing race and the second quenching part in the preheating inductor A and the heating inductor B;

[0017] Set the parameters of induction quenching, including: setting the heating power of both the preheating inductor A and the heating inductor B to 22 - 37 kW, setting the heating frequency of both the preheating inductor A and the heating inductor B to 4 - 5.5 kHz, setting the coupling gap between the preheating inductor A and the first quenching part to 2 - 5 mm, setting the coupling gap between the heating inductor B and the second quenching part to 1.5 - 4 mm, setting the rotation speed of the main bearing race to 120 - 180 mm / min, and setting the quenching liquid flow rate to 25 - 35 L / min;

[0018] Step three, cool the main bearing race that has completed induction quenching.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] A main bearing race quenching inductor provided by the present invention, by arranging a first quenching part and a second quenching part, simultaneously performs synchronous induction quenching on the rib and the raceway of the main bearing race, so as to improve the heating effect at the end of the inductor, optimize the uniformity of the hardened layer depth at the end, reduce the risk of quenching cracks, and improve the service life of the bearing. At the same time, by performing synchronous induction quenching on the rib and the raceway of the main bearing race, the present invention only needs to be quenched once and tempered once, which can save the total quenching and tempering time, improve production efficiency, and reduce the consumption of manpower and material resources.

[0021] In addition to the objectives, features, and advantages described above, the present invention has other objectives, features, and advantages. The following will further elaborate on the present invention with reference to the figures. Description of the Drawings

[0022] The drawings forming a part of this application are used to provide a further understanding of the present invention. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0023] Figure 1 is a schematic structural diagram of a main bearing ring quenching inductor in an embodiment of the present invention;

[0024] Figure 2 is Figure 1 a schematic structural diagram of the inductor body in ;

[0025] Figure 3 is a coupling schematic diagram between a main bearing ring quenching inductor and a main bearing ring in an experimental example of the present invention;

[0026] Figure 4 is a schematic diagram of the detection positions of the hardened layer depth of the main bearing ring in an experimental example of the present invention.

[0027] Wherein:

[0028] 1. First quenching part, 2. Second quenching part, 2.1. Copper retaining piece for fixing silicon steel sheets, 3. Heating coil, 4. Connecting part, 4.1. First connecting plate, 4.2. Second connecting plate, 5. Cold-rolled grain-oriented silicon steel sheet, 6. Induction ring. Detailed Embodiments

[0029] To make the above objectives, features, and advantages of the present invention more clearly understandable, the following will provide a detailed description of the specific embodiments of the present invention with reference to the drawings. It should be noted that the drawings of the present invention are all in simplified forms and use non-precise scales, only for conveniently and clearly assisting in the description of the embodiments of the present invention; the several mentioned in the present invention are not limited to the specific quantities in the drawing examples; the orientation or positional relationships indicated by 'front','middle', 'back', 'left', 'right', 'up', 'down', 'top', 'bottom','middle', etc. in the present invention are all based on the orientation or positional relationships shown in the drawings of the present invention, and do not indicate or imply that the devices or components referred to must have a specific orientation, nor can they be understood as a limitation of the present invention.

[0030] In this embodiment:

[0031] Refer to Figure 1 and Figure 2 As shown, a main bearing ring quenching inductor provided by the present invention includes an inductor body, a cold-rolled grain-oriented silicon steel sheet 5, and an induction ring 6;

[0032] The inductor body includes a first quenching part 1, a second quenching part 2, a heating coil 3 and a connecting part 4;

[0033] The first quenching part 1 is arranged in an n-shaped structure, and both ends of the first quenching part 1 are connected with the second quenching part 2, and after the two ends of the first quenching part 1 are connected with the second quenching part 2, an L-shaped structure is formed at each connection;

[0034] The heating coil 3 is connected with one of the second quenching parts 2;

[0035] The connecting part 4 includes a first connecting plate 4.1 and a second connecting plate 4.2 which are arranged at intervals. One end of the first connecting plate 4.1 is connected with an external heating element, and the other end of the first connecting plate 4.1 is connected with the heating coil 3; One end of the second connecting plate 4.2 is connected with an external heating element, and the other end of the second connecting plate 4.2 is connected with the other second quenching part 2.

[0036] The cold-rolled grain-oriented silicon steel sheet 5 is sleeved on the two second quenching parts 2 at the same time, and is used for induction quenching of the raceway of the main bearing ring;

[0037] The induction ring 6 is sleeved on the first quenching part 1, and is used for induction quenching of the rib of the main bearing ring.

[0038] Preferably, the heating coil 3 is preferably arranged as a hollow copper square tube structural member, and can be cooled by circulating cooling water to take away the heat generated by the inductor body itself during heating and the heat generated during the induction quenching of the main bearing ring.

[0039] Preferably, the cold-rolled grain-oriented silicon steel sheet 5 is preferably arranged as a high magnetic permeability grain-oriented silicon steel sheet (HiB).

[0040] Further preferably, a plurality of copper shims 2.1 for fixing the silicon steel sheet are arranged at intervals on the second quenching part 2, and the cold-rolled grain-oriented silicon steel sheet 5 is sleeved on the plurality of copper shims 2.1 for fixing the silicon steel sheet.

[0041] The specific process of performing induction quenching on the raceway and rib of the main bearing ring by using the above-mentioned main bearing ring quenching inductor is as follows:

[0042] Step 1: Preparation work;

[0043] Lift the main bearing ring onto the workbench of the quenching machine tool;

[0044] Align the main bearing ring;

[0045] Adjust the position of the jaws of the quenching machine tool to clamp and fix the main bearing ring;

[0046] Step 2: Induction quenching;

[0047] See Figure 3 As shown, two main bearing ring quenching inductors are arranged in parallel, and they are respectively defined as preheating inductor A and heating inductor B;

[0048] A coupling gap of 2 - 5 mm is set between the rib of the main bearing ring and the first quenching part in the preheating inductor A and the heating inductor B, and a coupling gap of 1.5 - 4 mm is set between the raceway of the main bearing ring and the second quenching part between the preheating inductor A and the heating inductor B;

[0049] Set the induction quenching parameters as shown in Table 1 to perform induction quenching on the main bearing ring;

[0050] Table 1: Induction quenching parameters

[0051] Preheating inductor A heating power (kW) 22-37 Heating inductor B heating power (kW) 22-37 Preheating inductor A frequency (kHz) 4-5.5 Heating inductor B frequency (kHz) 4-5.5 Coupling gap between preheating inductor A and the first quenching section (mm) 2-5 Coupling gap between heating inductor B and the second quenching section (mm) 1.5-4 Raceway rotation speed (mm / min) 120-180 Quenching liquid flow rate (L / min) 25-35

[0052] Step Three: Cooling;

[0053] Use PAG quenching liquid for spray cooling in a spraying manner.

[0054] Experimental Example 1:

[0055] Perform induction quenching on the main bearing ring using the induction quenching parameters shown in Table 2; The quenching test results are shown in Table 3. Near the oil tank position, there is no dagger-shaped hardened layer, the improvement effect of the layer depth uniformity is obvious, and there are no cracks in the oil tank.

[0056] Table 2: Induction quenching parameters

[0057]

[0058]

[0059] Table 3: Quenching results (hardened layer depth)

[0060] Detection position (see Figure 4 as shown) Position 1 Position 2 Position 3 Position 4 Hardened layer depth / mm 8.92 9.69 8.37 5.41

[0061] By detecting the quenching results (hardened layer depth) of different parts of the main bearing ring after induction quenching, the main bearing ring quenching inductor and the induction method provided by this application have the following features: improving the heating effect at the end of the inductor, optimizing the end thermal shape, enhancing the uniformity of the hardened layer depth, thereby improving the bearing service life; quenching the raceway and rib simultaneously to improve the quenching efficiency; reducing the risk of quenching cracks.

[0062] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A main bearing race quenching inductor, characterized in that, It includes an inductor body, cold-rolled grain-oriented silicon steel sheets (5), and an induction ring (6); The inductor body includes a first quenching part (1), a second quenching part (2), a heating coil (3), and a connecting part (4) connected in sequence; The cold-rolled grain-oriented silicon steel sheets (5) are simultaneously sleeved on two second quenching parts (2) for induction quenching of the raceway of the main bearing ring; The induction ring (6) is sleeved on the first quenching part (1) for induction quenching of the rib of the main bearing ring.

2. The quenching inductor for the main bearing race according to claim 1, characterized in that, The first quenching part (1) is arranged in an n-shaped structure, and both ends of the first quenching part (1) are connected with a second quenching part (2), and after the two ends of the first quenching part (1) are connected with the second quenching part (2), an L-shaped structure is formed; The heating coil (3) is connected with one of the second quenching parts (2); The connecting part (4) includes a first connecting plate (4.1) and a second connecting plate (4.2) arranged at intervals. One end of the first connecting plate (4.1) is connected with an external heating element, and the other end of the first connecting plate (4.1) is connected with the heating coil (3); One end of the second connecting plate (4.2) is connected with an external heating element, and the other end of the second connecting plate (4.2) is connected with the other second quenching part (2).

3. The quenching inductor for the main bearing race according to claim 1, wherein, The heating coil (3) is arranged as a hollow copper square tube structure member.

4. The quenching inductor for the main bearing race according to claim 1, wherein The cold-rolled grain-oriented silicon steel sheets (5) are arranged as high magnetic permeability grain-oriented silicon steel sheets.

5. The quenching inductor for the main bearing raceway according to claim 1, wherein On the second quenching part (2), a plurality of copper shims (2.1) for fixing the silicon steel sheets are also arranged at intervals, and the cold-rolled grain-oriented silicon steel sheets (5) are sleeved on the plurality of copper shims (2.1) for fixing the silicon steel sheets.

6. A method for induction hardening of a main bearing race, characterized in that, It includes the following steps: Simultaneously and juxtapositionally arrange two main bearing ring quenching inductors as described in any one of claims 1-5, and respectively define them as a preheating inductor A and a heating inductor B; Set a coupling gap of 2-5 mm between the rib of the main bearing ring and the first quenching part in the preheating inductor A and the heating inductor B, and set a coupling gap of 1.5-4 mm between the raceway of the main bearing ring and the second quenching part in the preheating inductor A and the heating inductor B; Set the parameters of induction quenching, including: set the heating power of the preheating inductor A and the heating inductor B to 22-37 kW, set the heating frequency of the preheating inductor A and the heating inductor B to 4-5.5 kHz, set the coupling gap between the preheating inductor A and the first quenching part to 2-5 mm, set the coupling gap between the heating inductor B and the second quenching part to 1.5-4 mm, set the rotation speed of the main bearing ring to 120-180 mm / min, and set the quenching liquid flow rate to 25-35 L / min; Step 3: Cool the main bearing ring that has completed induction quenching.

Images