What is the minimum required wall thickness of a superheater tube with 76 mm O.D. at 4150 kPa gauge pressure?

To determine the minimum required wall thickness of a superheater tube operating at a specific gauge pressure, one must refer to relevant codes and standards, such as the ASME Boiler and Pressure Vessel Code. For this calculation, the formula often used is based on the concepts of allowable stress and hoop stress.

The hoop stress can be calculated using the formula:

[

\sigma = \frac{P \times D}{2 \times t}

]

Where (P) is the internal pressure, (D) is the outer diameter, and (t) is the thickness of the material.

Given the outer diameter of the tube (76 mm) and the gauge pressure (4150 kPa), you would convert the gauge pressure into the same unit used for the diameter. Commonly, 1 kPa is equal to 1000 Pa, so 4150 kPa equals 4,150,000 Pa.

Using allowable stress values for materials (often derived from codes), you calculate the minimum thickness that will ensure the structure can safely withstand the internal pressure without failure.

The minimum wall thickness needed will account for factors such as corrosion allowance and the material's yield strength at the operating temperature. These parameters often guide the decision on