Machining Process of Each Component of Mill Bearing
I. Ring (Inner Ring / Outer Ring) Machining Process
|
Serial No. |
Process Name |
Key Requirements & Control Points |
|
1 |
Material Preparation |
Bar stock / Tube stock; Partial work pieces require forging + annealing / normalizing to eliminate stress |
|
2 |
Turning |
Rough turning for forming with grinding allowance reserved |
|
3 |
Heat Treatment |
Quenching + low-temperature tempering to ensure hardness HRC60–64 |
|
4 |
Rough Grinding |
Rough grinding of outer diameter, inner diameter and end faces |
|
5 |
Finish Grinding |
Finish grinding to dimensional tolerance and guarantee geometric accuracy |
|
6 |
Superfinishing / Fine Lapping |
Improve surface roughness |
|
7 |
Final Inspection |
Dimension, roundness, parallelism and roughness |
|
8 |
Rust Prevention & Warehousing |
Rust-proof treatment, waiting for matching and assembly |
II. Steel Ball Machining Process
|
Serial No. |
Process Name |
Key Requirements & Control Points |
|
1 |
Forming |
Cold heading of bar stock / wire rod into ball blanks |
|
2 |
Soft Grinding / Ball Polishing |
Chipping, rough grinding and soft grinding to improve spherical accuracy |
|
3 |
Heat Treatment |
Quenching + low-temperature tempering with hardness HRC60–64 |
|
4 |
Hard Grinding / Rough Grinding |
Remove oxide layer and stabilize dimension |
|
5 |
Finish Grinding |
Improve dimensional accuracy and roundness |
|
6 |
Fine Lapping / Super Lapping |
Achieve final surface quality |
|
7 |
Final Inspection & Sorting |
Sort by diameter accuracy grade |
|
8 |
Rust Prevention, Packaging & Warehousing |
Rust prevention and packaging, waiting for assembly |
III. Roller Machining Process
|
Serial No. |
Process Name |
Key Requirements & Control Points |
|
1 |
Forming |
Turning of bar stock / cold heading of wire rod |
|
2 |
Banding & Soft Grinding |
Unique process for rollers to guarantee reference datum |
|
3 |
Heat Treatment |
Quenching + low-temperature tempering |
|
4 |
Barrel Polishing / Soft Grinding for Deburring |
Correct heat treatment deformation |
|
5 |
Rough Grinding of Outer Diameter |
Remove machining allowance |
|
6 |
Rough Grinding of End Faces |
Secure length reference datum |
|
7 |
Fine Grinding of Outer Diameter |
Improve cylindricity |
|
8 |
Finish Grinding of End Faces |
Meet length tolerance |
|
9 |
Finish Grinding of Outer Diameter |
Reach final dimension |
|
10 |
Final Inspection & Sorting |
Sort by outer diameter and length |
|
11 |
Rust Prevention, Packaging & Warehousing |
Rust prevention and packaging, waiting for assembly |
IV. Cage Machining Process
(1) Stamped Cage
|
Serial No. |
Process Name |
Key Requirements & Control Points |
|
1 |
Sheet Shearing |
Cutting blank according to specified size |
|
2 |
Blanking |
Punch out basic outline of cage |
|
3 |
Stamping Forming |
Form pockets and structural profile |
|
4 |
Shaping, Deburring & Precision Machining |
Correct dimension and flatness |
|
5 |
Pickling / Shot Blasting / Barrel Polishing |
Remove burrs and oxide scale |
|
6 |
Final Inspection |
Pocket position, dimension and burr status |
|
7 |
Rust Prevention, Packaging & Warehousing |
Rust prevention and packaging, waiting for assembly |
(2) Solid Cage
|
Serial No. |
Process Name |
Key Control Points |
|
1 |
Material Preparation |
Bar stock / Tube stock / Forgings / Castings |
|
2 |
Turning |
Turning inner diameter, outer diameter, end faces and chamfers |
|
3 |
Drilling / Broaching / Boring |
Machine pockets and guarantee position tolerance |
|
4 |
Pickling |
Remove burrs and clean workpiece surface |
|
5 |
Final Inspection |
Dimension, position tolerance and burr status |
|
6 |
Rust Prevention, Packaging & Warehousing |
Rust prevention and packaging, waiting for assembly |