Question

A journal bearing has a shaft diameter of 75.00-mm with a unilateral tolerance of -0.02 mm. The bushing bore has a diameter of 75.10 mm with a unilateral tolerance of 0.06 mm. The bushing is 36 mm long and supports a load of 2 kN. The journal speed is 720 rpm. For the minimum clearance assembly find the minimum film thickness and the maximum lubricant pressure for SAE 20 and SAE 40 lubricants operating at an average film temperature of 60-degrees C

Answer 1

Aghe data >shaft diaTetun 95mm bcastr bushire bore 5.1mm 3 6 mm Guaumnc axN N 320pm naod to Calc ulode roolial Cloanane Cmin 5 Q.O5 mm 3.6 O5mm crd Yodius 3 5mD P 36 X35 SOmmmonteld numube. naed to frd We 2 S = Lu 18.5 mpas. fom SAE 20 At JAE 2D 3 5 S =O.69

Shart FYOTO 12 6 odd s 0.l6q for minimum Crant f\\m trick Nuuo ccentrict Yodio he O.20 he o 0lu5mY, he =minimum -flm Thiicns -O.olU5 mm Cubricant KOD And premunu at = O.l69 o.5 mar fl presuun O 3 Ps Psig Prex O 3u 2-35MPa Prran at 60c SAE UO AT SO, u 3 mpa 33 X 16 xF20 60 3.5 05 X O-Fu y i6 O.338

and h at S= 0.338 0.5 0.42 film h = Cxo u 0.05 X0UL Onc SO 33 at -5 presn YOutio fYomn2-21 chant O.38 Prar O 38 . Thu ma. Lubricant (Prersun or SAE UO JAE uD ka5mp9 0.021mm Pmax SAE 20 Q35 mpa h =0.otu5mm Thane ou