Calculation and selection of working clearance of rolling bearings (modification)

1. Actual effective interference calculation formula
△dy=△d-G
△d —— nominal interference
G - Flattening dimensions of interference fit
E.g:
Bearing inner diameter φ40 axis φ40
Nominal interference is +25μm
After 1/3 compression, the actual effective interference is +17 μm.

Press fit G
The surface roughness is 1 μm at 0.8.

2. Estimate formula for reducing radial clearance
1 bearing inner ring and steel solid shaft △j=△dy*
△j——The diameter expansion of the inner ring raceway rib (μm)
d - bearing inner diameter nominal size (mm)
H——diameter of inner ring raceway (mm)
2 bearing inner ring and steel hollow shaft △j=△dy*F(d)
F(d) = *
d1——Inner diameter of hollow shaft (mm)
3 bearing outer ring and steel body shell △A=△Dy*
△A—The diameter expansion of the outer ring raceway flange (μm)
△Dy——actual effective interference (μm) of shell hole diameter
D—— nominal diameter of bearing outside diameter (mm)
H - outer ring raceway flange diameter (mm)
4 bearing outer ring and steel thin-walled shell △A=△Dy*F(D)
F(D) = *
F——Outer diameter of bearing housing
5 bearing outer ring and gray cast iron shell
△A=△Dy[F(D)-0.15]
6 bearing outer ring and light metal shell
△A=△Dy[F(D)-0.25]

3. Reduction of clearance due to temperature difference in the inner ring

Δt = αΔt Do (mm)
In the formula, α-bearing steel has a coefficient of expansion of 1.12×10 (1/°C).
    Δt — temperature difference in the inner jacket (°C), Δt = T - outside T
     Do — Diameter of the outer ring raceway (mm).
   
4. Reduction of radial clearance
△j+△A+δt

5. Select the clearance range in the play group based on the amount of radial play reduction.
E.g:
Bearing type: 22332, the inner ring is subject to local heavy load, and axial movement of the sleeve, take g6 fit. The outer ring is subjected to the cyclic load and is tightly fitted with the housing hole. Take the P6 fit.
Inner ring: φ160 Axis: φ160
The maximum nominal interference △d = 11, G = 2.5 the actual effective interference amount △ dy = 4.8
d/h=160/191≈0.838
△j=△dy*d/h=4.8*0.838≈4
Outer ring: φ290 Outer hole: φ290
The maximum nominal interference △D = 79, G = 5 is the actual effective interference △ Dy = 48
H/D=258/290≈0.89
△A=△Dy*H/D=48*0.89≈43
Assume no other incoming heat. Δt =0
The amount of radial clearance reduction: Δj+ΔA+δt=4.8+31+0=35.8μm
According to the clearance range, select 2 groups of clearance (60~110μm)