- Technical knowledge center
- Principles of selecting bearing fits
- Hole tolerance fields H7-H11
- Typical fits of bearing nodes
- Reconditioning tolerances of holes for pins and bushings
- DIN 471 / DIN 472 circlips
- Slide bushings – types and selection
- Installation and removal of bearings – technical principles
Scope of application
This summary defines recommended regeneration tolerances for holes for pins and bushings used in construction and industrial machinery.
The values refer to regenerative machining performed after surfacing and hole boring.
It does not apply to special sliding sleeves or components made according to individual manufacturer’s documentation.
General principles of regeneration
Hole regeneration should provide:
- maintaining concentricity,
- Adequate working clearance for the pin,
- Stable pressing of the sleeve into the body,
- Limiting deformation during installation,
- The durability of the joint under dynamic loading conditions.
Tolerance selection depends on:
- nominal diameter,
- nature of the load,
- Operating conditions (impact, load variation),
- type of body material.
Regeneration tolerances for pin holes
The hole for the pin should provide mounting clearance and working clearance to allow the joint to operate freely.
The value of positive deviation determines the increase in the diameter of the hole relative to the nominal dimension of the pin.
Regeneration tolerances for pin holes
| Nominal diameter range [mm] | Permissible deviation [mm]. | Nature of the fit |
|---|---|---|
| 20 – 30 | +0.04 to +0.05 | Mounting clearance |
| 30 – 50 | +0.05 to +0.06 | Mounting clearance |
| 50 – 80 | +0.06 to +0.09 | Working clearance |
| 80 – 120 | +0.09 to +0.12 | Working clearance |
| 120 – 180 | +0.12 to +0.15 | Working clearance |
| 180 – 250 | +0.15 to +0.25 | Increased clearance |
Regenerative tolerances for bushing holes
The hole for the bushing should be made with a negative deviation to ensure that the bushing is pressed into the socket.
The value of the deviation determines the reduction in the diameter of the hole relative to the outer diameter of the sleeve.
Regenerative tolerances for bushing holes
| Nominal diameter range [mm] | Permissible deviation [mm]. | Nature of the fit |
|---|---|---|
| 20 – 30 | -0.03 to -0.04 | Light pressing |
| 30 – 50 | -0.04 to -0.06 | Press |
| 50 – 60 | -0.06 to -0.07 | Press |
| 60 – 70 | -0.07 to -0.08 | Increased pressure |
| 70 – 80 | -0.08 to -0.09 | Increased pressure |
| 80 – 100 | -0.09 to -0.12 | Powerful push |
| 100 – 120 | -0.12 to -0.15 | Powerful push |
| 120 – 150 | -0.15 to -0.20 | Industrial pressing |
| 150 – 200 | -0.20 to -0.30 | Industrial pressing |
Inspection after regeneration
After machining, check:
- nominal diameter and tolerance range,
- Ovality,
- The concentricity of the regenerated holes,
- surface roughness,
- The quality of the surfacing before post-processing.
Measurement should be done with a feeler gauge or internal micrometer.
