0
Why does the Barlow formula use the outside diameter when the pressure relates to the inside diameter?
The Barlow formula is a simplification of Lame's formula for thin walled pipes/ cylinders. The book by AP Moser (Buried Pipe Design) gives the derivation and arrives at S = PD/2t where D is infact the average diameter. This makes sense if you consider that there is a stress profile across the pipe wall with highest stress at the inside edge. So the average stress occurs in the material at the centre (ie. Do - t). The above book has a couple of good sketches illustrating this. Outer diameter is however quoted in the Barlow equation in some contexts - for example in ASME 31.8. This is apparently a simplification (infact nominal outside diameter is used which is actually a bit smaller than the real outer diameter). If using the formula to calculate wall thickness the answer will be slightly conservative but then you will generally look up a standard wall thickness (eg. from the table in ANSI B36.10) so you will likely arrive at the same answer anyway.
What else can I help you with?
What mathematical formula relates pressure force and area?
Pressure =Force/Area
How do you calculate radius when the have no radius and no diameter?
You use the information that you do have, and a formula that relates it to theradius or diameter of the circle. As an example: The circumference is very helpfulif you know it.
What is pi as it relates to circumference and diameter of a circle?
pi = circumference / diameter
When was eulers formula discovered?
Euler published the formula, which relates complex exponentials to trigonometric functions in 1748. See related link.
What is an equation that relates two or more quantities?
A mathematical formula, such as Speed = Distance / Time for example.
What mathematical formula relates pressure force and area?
Pressure =Force/Area
How do you calculate radius when the have no radius and no diameter?
You use the information that you do have, and a formula that relates it to theradius or diameter of the circle. As an example: The circumference is very helpfulif you know it.
How can I calculate altitude from pressure?
To calculate altitude from pressure, you can use the barometric formula, which relates pressure to altitude. This formula takes into account the atmospheric pressure at sea level, the pressure at the given altitude, and the temperature of the air. By plugging in these values, you can determine the altitude based on the pressure reading.
How do air pressure relates to earth?
What in the community relates to air pressure?
What is pi as it relates to circumference and diameter of a circle?
pi = circumference / diameter
How to find density with temperature and pressure?
To find density with temperature and pressure, you can use the ideal gas law equation: density (pressure)/(gas constant x temperature). This formula relates the density of a gas to its pressure and temperature.
What quantity relates to pressure?
PSI
Elevated water tank psi to feet formula?
The formula to convert water tank pressure (psi) to feet of head is: Feet = psi * 2.31. This formula is derived from the equation for hydrostatic pressure, which relates pressure to the height of a fluid column.
The special number that relates the diameter of a circle to its circumference is?
Pi (3.14159265358.....)
What equation relates pressure to force and area?
The equation that relates pressure, force, and area is: Pressure = Force / Area. This equation states that pressure is equal to the force applied per unit area.
What mean by bore of a gun?
The bore of a gun relates to the diameter of the hole in the barrel - and in turn the diameter of the bullet the gun can fire.
What formula relates wavelength and period?
The formula that relates wavelength (λ) and period (T) for a wave is: λ = v * T, where v is the speed of the wave.
