darkmagic said:Is J there the J of the smaller circle, with the inside diameter? I got 243 Mpa which is larger than 150 Mpa.
The inside diameter of a hollow steel shaft can be calculated by subtracting the wall thickness from the outside diameter. The wall thickness can be measured using a caliper or obtained from the manufacturer's specifications.
The formula for calculating the stress of a hollow steel shaft is: σ = (M * c) / (π * r^3), where σ is the stress, M is the bending moment, c is the distance from the neutral axis to the outermost fiber, and r is the radius of the shaft.
The inside diameter is typically measured in millimeters (mm) or inches (in), while stress is measured in units of pressure, such as pounds per square inch (psi) or megapascals (MPa).
The calculations for inside diameter and stress of a hollow steel shaft can be applied to any shape, as long as the dimensions and material properties are known. However, the formula mentioned in question 2 is specifically for round shafts. Different formulas may be needed for calculating the stress of non-circular shafts.
The calculated stress of a hollow steel shaft is an important factor in engineering design as it helps determine the strength and load-bearing capacity of the shaft. Engineers can use this information to select the appropriate material and dimensions for the shaft, ensuring it can withstand the expected loads and operate safely.