Home>Bearing knowledge> Cold treatment of the ring

/*728*90 created on 2018/5/16*/ var cpro_id = "u3440131";

Cold disposal of the ferrule

---

/*250*250 was created on 2017/12/25*/ var cpro_id = 'u3171089';

After the workpiece is quenched and cooled to room temperature; it should be placed in the environment below room temperature for a certain time; taken out at room temperature; this lower temperature treatment is called cold treatment. The cold treatment of bearing steel is often used in the freezer and dry ice alcohol solution. .
1. The effect of cold treatment is that the fine bearing has higher requirements for dimensional stability, after the ring is quenched (especially after stage quenching); the internal arrangement still retains more retained austenite; this residual austenite is an unstable arrangement; During storage and operation of the bearing; it will change continuously; then the accuracy of the bearing will be changed. For this purpose, a cold treatment process is selected; it can reduce the remaining austenite in the arrangement; slightly improve the hardness of the part.
2. Cold treatment process after quenching at room temperature: after quenching; must be allowed to cool the ferrule surface to room temperature after cold treatment; otherwise simple cracking; cold to room temperature immediately after cold treatment (usually not exceed 30min); otherwise it will break The transformation of the body to martensite.
Cold treatment temperature: The temperature of cold treatment is mainly based on the martensite transformation stop temperature Mf of steel; the other is to consider the influence of cold treatment on mechanical properties and processability.
About GCr15 steel; cold treatment is selected at -70 °C, when the ferrule or equipment with low precision requirement is restrained; cold treatment temperature can be -40 ~ -70 °C, ultra-fine bearing; can be -70 °C ~ -80 Cold treatment between °C. The temperature of the supercooling affects the bearing impact fatigue and the touch life.
Cold treatment insulation: Although many martensite transformations are completed at a cold to a certain temperature A; but in order to make a batch of ferrules and the heart evenly reach the cold treatment temperature; demand must be the insulation moment; usually 1 ~1. 5h.
Tempering after cold treatment: The ferrule is placed in the air after cold treatment, and the temperature is slowly raised to room temperature and then tempered in time. The temperature rise cannot be too fast; otherwise, simple cracking and tempering are timely; otherwise the inside of the ferrule is larger Residual stress will cause the ferrule to crack; usually does not exceed 2h.

---

Recommend to friends comments close window

Bearing related knowledge

KOYO imported bearings improve shaft support rigidity skills Application of CSB-LIN linear bearing in machinery INA linear bearing high quality tapered roller bearing 32019X SKF bearing sizable bearing life types and basic concepts

This article links to http://
Please indicate China Bearing Network http://

Previous:Analysis of the fundamental functional requirements of bearing steel Next: Analysis of disposal methods for imported bearings

Stainless Steel Wire

Stainless Steel Wire,Stainless Steel Wire Mesh,Stainless Wire,Stainless Wire Mesh

ANPING HONGYU WIREMESH CO.,LTD , https://www.hongyufence.com