Conversion between m3/h, Sm3/h, and Nm3/h? ?

Nm3/h is based on 0°C as the standard; the suction volume of a standard compressor in m3/h is usually determined using 20°C as the standard, or it is based on the suction temperature provided by the user. If it is necessary to convert m3/min to Nm3/h, the conversion can be done using the ideal gas law: PV=nRT. Since nR remains constant, the conversion is possible depending on whether standard conditions or other operating conditions apply.

Sm3 refers to the volume of a gas under control conditions (reference conditions) (usually 20 degrees Celsius and 1 standard atmosphere). Reference: According to the \"Code for Selection and Design of Automation Instruments in Petrochemical Industries\", page P8, as well as the definition established by the 10th General Conference on Weights and Measures (CGPM) in 1954, the standard state is defined as 0 degrees Celsius and 0.101 MPa ； Page 204 of \"Automatic Detection Technology and Devices\" (edited by Zhang Hongjian), as well as the \"Standard Orifice Plate Calculation Method for Natural Gas Flow Rate\", define the standard condition as: a temperature of 293.15 K (20°C) and a pressure of 101.325 KPa

Don’t tell me to calculate using the ideal equation of state; it’s essential to give the conversion result directly.

This post was last edited by zmg813 on 2011-8-4 at 10:28. This unit refers to the volume of gas; since gases are compressible, when measuring gas in terms of volume, it is necessary to specify the physical conditions of the gas at the time of measurement. Nm3 refers to the volume of a gas at 0 degrees Celsius and 1 standard atmosphere ； m3 refers to the volume of the gas under actual operating conditions ； Sm3 refers to the volume of a gas under control conditions (reference conditions) (usually 20 degrees Celsius and 1 standard atmosphere). The conditions required for their relationship are to know exactly what pressure the m3/h value is at, as well as the exact temperature. There is the formula P1V1/T1=P2V2/T2; Nm3/h is commonly referred to as standard cubic volume, which represents the displacement under standard conditions. For a compressor used in Tibet and one used in Shanghai, the displacement, when expressed in m3/h, differs significantly; however, when converted to cubic meters, the value is the same

Conversion between Nm3/h and Sm3/h: (P mark *1)/273 = (P mark *Vs)/(273+20). Therefore, Vs = (273+20)/273 = 1.073. Hence, 1 Nm3/h = 1.073 Sm3/h. Is the calculation above correct? ? ?

Your understanding is correct; both Nm3/h and Sm3/h refer to the standard state, with only the temperature differing. The value obtained by directly taking the ratio is the conversion value between them.

Reply to 5# zmg813: You have it backwards; it should be 1Sm3/h = 1.073 NM3/h!

The one with the higher temperature is the larger one, I guess……

I don’t understand. . . . . . . . . . . .