Bearing Stress Analysis

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Input values cells

Input values (from bearing supplier data)

Results (do not touch these cells)

To determine deflection of a bearing supported beam

Shaft

distance between bearings (>3Dshaft), b (mm) 20

Location of first bearing from end of shaft, a (mm) 20

Total shaft length, L (mm) 40

Length increment, Linc (mm) 0.4

Modulus of elasticity, E (N/mm^2) 69000

Shaft material density, rho (kg/m^3) 2630

Shaft diameter, Dshaft (mm) 6

Moment of inertia, I (mm^4) 63.617

Distance farthest fiber to nuetral axis, cc (mm) 3

Bearings

length, Lb (mm) 6

thickness, tbear (mm) 1

material modulus, Eb (N/mm^2) 2000

diametrical clearance to shaft, dc (mm) 0.1

Allowable small misalignment angle, tallow (radians) 0.016949

PV continuous, PVC (N/mm^2-mm/s) 1800

PV short periods, PVmax (N/mm^2-mm/s) 3500

Maximum allowable contact pressure, qmax (N/mm^2) 30

radial stiffness, Kbear (N/mm) 72000

Support structure

radial stiffness at bearing support points, Kstruct (N/mm) 10000

System Summary Accept?

Total system dislacement at load, disp (mm) -0.017844

Total shaft slope at load, slope (mm) 0.000930

Maximum shaft slope at bearing, tmax (radians) 0.000475 OK 

Max applied contact pressure, qappmax (N/mm^2) 0.56 OK  

Max applied PV, PVappmax (N/mm^2-mm/s) 5.82 OK  

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 Loading

Point load, F (N) 10

Shaft speed, w (rpm) 100 Shaft

Shaft whip speed, wwhip (rpm) 452691

Shaft tangential speed, vshaft (mm/s) 10.5

Maximum deflection (mm) -0.012150

Maximum slope (radians) 0.000759

Bearing reaction forces

20.00-10.00

Shaft deflections

0.000304

-0.000152

0.000759

0.000000

0.000000

-0.012150

Bearing and structural deflections

-0.002278

0.001139

shaft slope, ts (radians) 0.000171

resulting deflection at point load, ds (mm) -0.005694

Integration constants

C_3 3333.33

C_4 -53333.33

Safety factor

35.7

54.0

601.6

resulting d

R A

, Ra (N)

R B, Rb (N)

θA, ta (radians)

θB, tb (radians)

θF, tf (radians) (slope at load application)

δA, da (mm) θF, tf (rad

δB, db (mm)

δF, df (mm) deflection at load application)

δA, dab (mm)

δB, dbb (mm)

δF, df (mm

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Allowable small misal

F

a

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FORMULAE

Shaft whip speed, wwhip (rpm)

tangential speed, vshaft (mm/s)

shaft slope, ts (radians)

eflection at point load, ds (mm)

R A, Ra (N)

R B, Rb (N)

θA, ta (radians)

θB, tb (radians)

ians) (slope at load application)

δA, da (mm)

δB, db (mm)

) deflection at load application)

δA, dab (mm)

δB, dbb (mm)

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C_3

C_4

ignment angle, tallow (radians)

radial stiffness, Kbear (N/mm)

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