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Gas Pipe Sizing Formula

Gas Pipe Sizing Formula

Gas Pipe Sizing Formula



I'm chasing a couple of things to assist with design of a gas service for a high rise apartment building.

a) The most suitable formula to use in sizing the pipework. System would be 100 mm and supply pressures 2.75 kPa thru to 70 kPa.
b) As I understand it equivalent lengths are typically used for fittings, is there a metric source I could refer to with this data?
c) Some information on diversities for residential gas supplies, what sort of percentage or method to determine diversity is typically used?

I'm dealing in metric.

One formula I have been sent is as follows for calculating outlet pressure:

P = ( Absolute Inlet Pressure^2 - ( (m3/hr / Constant)^2 * Specific Gravity * Length) / Diameter ^ 5) ) )^0.5

Anyone able to confirm which formula it is and if suitable?

Thanks in advance


RE: Gas Pipe Sizing Formula


Thank you for your assistance.

For reference should anyone come across this post, with regards to diversity, I found two references.

a) International Mechanical Code 1988


b) ASPE Data Book Volume 2, Figure 7-5 Typical Diversity Curve for Gas Supply to High Rise Apartments



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