Hard turning HRC60 bearings with CBN Insert obvious advantag
Category：News
PublishedDate：2017-10-19
Bearings, as one of the most important components, have been widely used in many industries. With the requirements of the production, it required high on the performance of the bearings. Heat treatment is one of the common process for bearings, and after that, bearings will have high hardness, and difficult to machine, and it will produce some problems when machining bearings with traditional cutting tools:
(1) The hardness of the bearing after heat treatment will be above HRC45,and some will be above HRC60, if use traditional cutting tools, it will wear rapidly, and affect the efficiency.
(2) Some bearings will exist interrupt turning condition. If the bearings have keyway or oil hole, traditional cutting tools(carbide insert, ceramic insert) will be easily chipping, and the tool costs will be high.
(3) For large scale bearings, such as slewing bearings, it will have high hardness after heat treatment, and the deformation is large, it will require high on the wear resistance and the impact resistance of the cutting tools
Specific for large scale bearings, we can choose ceramic cutting tools and cbn insert.
Ceramic cutters can be only used for small allowance and finishing process. If the allowance is more than 1mm or it exists interrupt turning condition, you’d better choose cbn insert.
CBN Insert has high hardness, about HRC95, is the right choice for hard turning bearings. And the common grades include BN-S20, BN-S200 and BN-H11 PCBN Insert.
BN-S20 and BN-S200 belong to solid cbn insert, not only can be used for large allowance, but also avoid failure risk. BN-H11 belong to brazing pcbn insert, has more cutting edges, has excellent wear resistance and heat resistance. When finish turning bearings, it not only can make sure the precision, but also can ensure the Roughness Ra0.8.
The recommend cutting data as follows:
|
Machining Materials |
Cutting Speed Vc (m/min) |
Cutting Depth ap (mm) |
Feed Rate Fr (mm/r) |
Common CBN Grade |
|
High hardness steel |
50~150 (Roughing) |
1~10 |
0.15~0.7 |
BN-S20 |
|
60~250 (Finishing) |
≤1 |
0.05~0.35 |
BN-S20,BN-S200,BN-H11 |
The application case with Halnn CBN Insert machining Bearings
|
Insert Description |
Workpiece Details |
|
|
Insert Model |
SNGN120712 |
Component |
Slewing Bearings |
|
|
Tool Holder |
CSDNN |
Materials |
42CrMo |
|
|
Previous Cutting Tools |
Grinding |
Hardness |
HRC47-55 |
|
|
Cutting Data |
Component and Insert Image |
|
|
Vc（m/min） |
100~150 |
|
|
|
Fr（mm/r） |
0.15~0.7 |
|
|
ap（mm） |
1~4 |
|
|
Machining Effect: With same precision requirements, the efficiency of BN-S20 Solid CBN Insert is 4 times of grinding process, and the costs only about 20%. |
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|
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If you have any problems on turning bearings, please feel free to contact with us info@halnntools.com, skype:info@halnntools.com, Whatsapp:+8615617635382