CN112692522A - Deep groove ball inner ring ball mounting gap processing method - Google Patents
Deep groove ball inner ring ball mounting gap processing method Download PDFInfo
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Abstract
A deep groove ball inner ring ball-mounting notch processing method relates to the field of bearings. The invention aims to solve the problems that the precision of a channel in the processing of a single-row deep groove ball bearing with a ball loading notch cannot be ensured and the rejection rate is high. The processing method comprises the following steps: forging → lathing → heat treatment → coarse grinding → three times of low temperature supplement tempering → finish grinding → fine grinding → milling notch → grinding notch → submitting. According to the invention, through the technical research, the qualification rate of the product is greatly improved, the quality stability of the domestic bearing processing process is improved, the processing cost is reduced, the economic benefit of a company is improved, and the core competitiveness of the company is enhanced. The invention is applied to the field of bearing processing.
Description
Technical Field
The invention relates to the field of bearings, in particular to a method for processing a deep groove ball inner ring ball-mounting notch.
Background
The single-row deep groove ball bearing with the ball loading gap is provided with the ball loading gap on the inner ring and the outer ring respectively, so that more and larger balls can be used than the standard deep groove ball bearing. The bearing with the ball gap has a higher radial load capacity than the bearing without the ball gap, but its axial load capacity is small. Due to the structural characteristics of the ferrule, the precision of a channel in processing is difficult to guarantee, the rejection rate is high, the delivery progress is seriously influenced, and the process of home-made substitution of the type of aviation bearing is restricted. At present, other bearing enterprises in China process the deep groove ball loading gap structure according to the traditional process route, and the product percent of pass is low. A great deal of resource waste is caused in the processing process, and the delivery cycle of the product is influenced.
Disclosure of Invention
The invention aims to solve the problems that the precision of a channel cannot be ensured and the rejection rate is high in the processing of a single-row deep groove ball bearing with a ball loading notch, and provides a method for processing the ball loading notch of an inner ring of a deep groove ball
The invention relates to a method for processing a deep groove ball inner ring ball-mounting notch, which is carried out according to the following steps:
turning the forge piece, carrying out coarse grinding after heat treatment, carrying out low-temperature tempering for three times, carrying out final grinding, milling a notch after fine grinding, and grinding the notch to obtain a ferrule, namely finishing the machining of the deep groove ball inner ring ball-mounting notch; the temperature of the low-temperature tempering is not more than 150 ℃; the temperature of the third low-temperature tempering is the same;
wherein, the notch milling is carried out by adopting a five-axis machining center, and the adopted milling cutter is a phi 20 four-edge hard alloy milling cutter; and milling a notch, and aligning the used mould within 0.02.
Further, the notch milling is carried out by adopting a five-axis machining center, and specifically comprises the following steps:
utilizing a main shaft swinging head of a five-axis machining center, utilizing a phi 20 four-blade hard alloy milling cutter, cutting in and out an arc, spirally feeding, and milling by utilizing a side blade of a cutter; wherein, milling is divided into rough milling and finish milling.
Furthermore, the used clamping fixture is clean, the clamping of the workpiece and the clamping fixture is ensured in the processing, and the clamping surface of the workpiece has no clamping trace.
Further, the thinnest part of the processed ferrule is 3.5mm, and the maximum part of the outer diameter dimension is phi 110.
Further, after the notch is milled, burrs of the notch are removed, the edge of the notch is rubbed by fine sand paper, and the acute angle of the edge of the notch is 0.2 at most.
Further, the material of the processed ferrule is GCr 15.
The technical design principle of the invention is as follows:
the deep reasons of low product qualification rate of the traditional process route are optimized aiming at the deep reasons.
The original route is as follows:
forging → lathing → milling notch → heat treatment → coarse grinding → low temperature supplement tempering → finish grinding → fine grinding → grinding notch → submitting. If the route is adopted, the notch is roughly machined before the heat treatment, the notch machining efficiency is high, the requirement on the cutter is not high, and after the groove is finely ground, the notch is finely machined. However, in the channel lapping process, the notches on the channel can affect the swinging of the oilstone, and the notches can damage the oilstone, so that the roundness of the channel lapping and the channel type error are out of tolerance, which is also a main reason for low product yield.
Because this lasso is GCr15, and hardness is 62 ~ 66HRC, adopts once low temperature to supplement the tempering after the corase grind, and the inside residual stress of lasso can produce the condition of not thoroughly eliminating, can lead to milling back stress release like this, consequently for guaranteeing machining precision, the route after the optimization is:
forging → lathing → heat treatment → coarse grinding → three times of low temperature supplement tempering → finish grinding → fine grinding → milling notch → grinding notch → submitting.
1. Optimizing the selection of the cutter;
the cutter is one of key elements of a hard milling process, the ferrule material GCr15 is a hardenability material, the hardness of the material is 62-66 HRC, the notch milling process is arranged after heat treatment, the cutter needs to run stably, the two sides of the milling cutter are uniformly stressed and heat is uniformly generated, and the hard milling end mill with the cutter edge of a machine body made of integral hard alloy and subjected to coating treatment is selected. In order to ensure that the cutter has certain rigidity and wear resistance, a phi 20 four-edge hard alloy milling cutter is selected.
2. The process control means is researched, the machining process is ensured to be controllable, and the machining qualification rate is improved
a. Because the precision requirement of the ferrule notch is high and a 7-degree inclination angle is required, a five-axis machining center is selected for machining.
b. In order to ensure the accuracy of the notch, the clamping fixture is aligned within 0.02.
c. The method comprises the steps of utilizing a spindle head swinging function of a five-axis machining center, adopting a phi 20 hard milling cutter to cut in and out an arc, carrying out spiral feeding, utilizing a side edge of a cutter to carry out milling, and carrying out rough milling and finish milling.
d. The mould can not have the filth, ensures that the work piece presss from both sides tightly, and notices that the clamping face can not have the tight trace of clamp, and processing is accomplished the initial survey back, detects whether the work piece has the deformation to and whether the breach size is qualified (need measure the initial ovality of work piece before the processing), guarantee that the initial ovality is unchangeable after the processing.
e. And after the notch is milled, removing notch burrs, lightly rubbing the edge of the notch by using fine sand paper, and paying attention to avoid scratching the working surface, wherein the acute angle is 0.2 at most.
4. Selecting proper clamping mode
As the ferrule belongs to an ultra-light and ultra-light product (the thinnest part is 3.5mm), the outer diameter is larger than phi 110, and in order to reduce clamping deformation and clamp force, the inner diameter and end face positioning and end face pressing modes can be adopted.
The invention has the following beneficial effects:
according to the invention, through the technical research, the qualification rate of the product is greatly improved, the quality stability of the domestic bearing processing process is improved, the processing cost is reduced, the economic benefit of a company is improved, and the core competitiveness of the company is enhanced.
Drawings
FIG. 1 is a workpiece view;
FIG. 2 is a tooling diagram; wherein, 1 is the opening clamp plate, 2 is the bolt, 3 is the locating pin, and 4 is the base.
Detailed Description
It will be understood by those of ordinary skill in the art that the foregoing embodiments are specific examples for carrying out the invention, and that various changes in form and details may be made therein without departing from the spirit and scope of the invention in practice.
To make the objects, aspects and advantages of the embodiments of the present invention more apparent, the following detailed description clearly illustrates the spirit of the disclosure, and any person skilled in the art, after understanding the embodiments of the disclosure, may make changes and modifications to the technology taught by the disclosure without departing from the spirit and scope of the disclosure.
The exemplary embodiments of the present invention and the description thereof are provided to explain the present invention and not to limit the present invention.
Example 1
The method for processing the deep groove ball inner ring ball-mounting notch of the embodiment comprises the following steps:
forging → lathing → heat treatment → coarse grinding → three times of low temperature supplement tempering → finish grinding → fine grinding → milling notch → grinding notch → submitting.
The method specifically comprises the following steps: turning the forge piece, carrying out coarse grinding after heat treatment, carrying out low-temperature tempering for three times, carrying out final grinding, milling a notch after fine grinding, and grinding the notch to obtain a ferrule, namely finishing the machining of the deep groove ball inner ring ball-mounting notch; the temperature of the low-temperature tempering is not more than 150 ℃; the temperature of the three times of low temperature tempering is the same.
The ferrule material GCr15 processed in the embodiment is a hardenability material, the hardness of the material is 62-66 HRC, the notch milling process is arranged after heat treatment, a cutter needs to run stably, the two sides of the milling cutter are uniformly stressed and generate heat uniformly, and the hard milling end mill with the cutting edge of a whole hard alloy body subjected to coating treatment is selected.
Because the precision requirement of the ferrule notch is high and a 7-degree inclination angle is required, the five-axis machining center is selected for milling the notch in the embodiment, in order to ensure that the cutter has certain rigidity and wear resistance, a phi 20 four-edged hard alloy milling cutter is selected,
because the precision requirement of the ferrule notch is high and a 7-degree inclination angle is required, a five-axis machining center is selected for machining; in order to ensure the accuracy of the notch, the clamping fixture is aligned within 0.02; the method is characterized in that a spindle head swinging function of a five-axis machining center is utilized, a phi 20 hard milling cutter is used for arc cutting-in and cutting-out, spiral feeding is adopted, side edges of the cutter are utilized for milling, and milling is divided into rough milling and finish milling. The mould can not have the filth, ensures that the work piece presss from both sides tightly, and notices that the clamping face can not have the tight trace of clamp, and processing is accomplished the initial survey back, detects whether the work piece has the deformation to and whether the breach size is qualified (need measure the initial ovality of work piece before the processing), guarantee that the initial ovality is unchangeable after the processing. And after the notch is milled, removing notch burrs, lightly rubbing the edge of the notch by using fine sand paper, and paying attention to avoid scratching the working surface, wherein the acute angle is 0.2 at most. As the ferrule belongs to an ultra-light and ultra-light product (the thinnest part is 3.5mm), the outer diameter is larger than phi 110, and in order to reduce clamping deformation and clamp force, the inner diameter and end face positioning and end face pressing modes can be adopted.
The part qualification rate after the processing of the embodiment reaches more than 80%. The table for comparing the ovality of the front channel and the rear channel after milling for 10 groups of ferrules is as follows:
milling front and back comparison table of channel ovality before improvement (unit: mum)
| Serial number | Before milling | After milling | Amount of |
| 1 | 0.56 | 2.08 | 1.52 |
| 2 | 0.22 | 1.54 | 1.32 |
| 3 | 0.27 | 0.82 | 0.55 |
| 4 | 0.38 | 1.82 | 1.44 |
| 5 | 0.51 | 1.27 | 0.76 |
| 6 | 0.35 | 1.62 | 1.27 |
| 7 | 0.37 | 1.39 | 1.02 |
| 8 | 0.48 | 1.5 | 1.02 |
| 9 | 0.21 | 0.61 | 0.4 |
| 10 | 0.24 | 0.74 | 0.5 |
Improved back channel ovality milling front and back comparison table (unit: mum)
| Serial number | Before milling | After milling | Amount of |
| 1 | 0.45 | 0.82 | 0.37 |
| 2 | 0.36 | 0.75 | 0.39 |
| 3 | 0.38 | 0.85 | 0.47 |
| 4 | 0.46 | 0.96 | 0.5 |
| 5 | 0.51 | 1.05 | 0.54 |
| 6 | 0.48 | 1.21 | 0.73 |
| 7 | 0.34 | 1.25 | 0.91 |
| 8 | 0.21 | 0.63 | 0.42 |
| 9 | 0.28 | 0.54 | 0.26 |
| 10 | 0.38 | 0.74 | 0.36 |
。
Claims (6)
1. The processing method of the deep groove ball inner ring ball loading gap is characterized by comprising the following steps of:
turning the forge piece, carrying out coarse grinding after heat treatment, carrying out low-temperature tempering for three times, carrying out final grinding, milling a notch after fine grinding, and grinding the notch to obtain a ferrule, namely finishing the machining of the deep groove ball inner ring ball-mounting notch; the temperature of the low-temperature tempering is not more than 150 ℃; the temperature of the third low-temperature tempering is the same;
wherein, the notch milling is carried out by adopting a five-axis machining center, and the adopted milling cutter is a phi 20 four-edge hard alloy milling cutter; and milling a notch, and aligning the used mould within 0.02.
2. The deep groove ball inner ring ball-mounting notch processing method of claim 1, wherein the milling notch is processed by a five-axis processing center, specifically:
utilizing a main shaft swinging head of a five-axis machining center, utilizing a phi 20 four-blade hard alloy milling cutter, cutting in and out an arc, spirally feeding, and milling by utilizing a side blade of a cutter; wherein, milling is divided into rough milling and finish milling.
3. The method of claim 1, wherein the clamping fixture is clean, the clamping of the workpiece and the clamping fixture is ensured during the machining, and the clamping surface of the workpiece has no clamping mark.
4. The method of claim 1, wherein the thinnest part of the ferrule is 3.5mm, and the largest part of the outer diameter is phi 110.
5. The method of claim 1, wherein after milling the gap, burrs are removed and the edge of the gap is rubbed with fine sand paper, the acute angle of the edge of the gap being 0.2 at most.
6. The method of claim 1, wherein the material of the ferrule is GCr 15.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114523140A (en) * | 2022-02-25 | 2022-05-24 | 中国航发哈尔滨轴承有限公司 | Machining method for milling notch of thrust ball bearing retainer |
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