The drilling pipe on an oil rig is made from steel pipe which having thickness of 5-mm and an outside diameter of 90-mm. calculate the maximum shear stress occur in the pipe if the pipe is turning at 650 rev/min while being powered using 12kw motor.

Explanation:

outside diameter = 90 mm

inside diameter = 90- 2× t=  90- 2× 5 = 80mm

where t is thickness of pipe.

power (P)  = 12 kW

Revolution (N)= 650 rev/min

we

Power = torque × angular velocity

P= T× ω

ω =  

T=  176.3 Nm

for maximum shear stress

where ymax is maximum distance from neutral axis.

= 45 mm

= polar moment area

          =

          = 2,420,008 mm⁴

answer:

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explanation: