Question

A boiler of 1.6 m diameter is made of a 20-mm thick plate. What will be the permissible steam pressure in the boiler in the maximum tensile stress in the plates must NOT exceed 80 MPa?

• A. 2 МРа
• B. 2 GPa
• C. 20 MPa
• D. 20 GPa

Answer 1

Answer:

A. 2 МРа

Given: $d = 1.6m$, $t = 20mm$ $\sigma_{max} =80 MPa = \sigma_{l}$ (Longitudinal stress). Maximum working stress, $\sigma_l= \sigma_h=\frac {Pd}{2t} \Rightarrow P = \frac{2t\sigma_b}{d}=\frac{2\times 20\times 80}{1.6\times1000} = 2 MPa$