Conversion between Nm3/hr to Sm3/hr and vice versa
Conversion between Nm3/hr to Sm3/hr and vice versa
(OP)
Hi all,
I am just curious when do you use Nm3/hr and Sm3/hr. How do you convert between the two units?
Please help.
Thank you.
Chemprocess
I am just curious when do you use Nm3/hr and Sm3/hr. How do you convert between the two units?
Please help.
Thank you.
Chemprocess





RE: Conversion between Nm3/hr to Sm3/hr and vice versa
RE: Conversion between Nm3/hr to Sm3/hr and vice versa
Once you have the temperature and pressure references it is a simple matter to do the conversion.
RE: Conversion between Nm3/hr to Sm3/hr and vice versa
Messrs tickle and katmar are both right.
Some experts consider NTP and STP -reference conditions- as equivalent terms. Notwithstanding their expertise, they should clearly indicate T and P to enable making conversions to differing T or P values.
RE: Conversion between Nm3/hr to Sm3/hr and vice versa
The importance of the defining T & P values are very important. I had one experience where there was a dispute on the amount of hydrogen exported to another plant from one plant in an integrated petrochemical complex. It turns out that one plant was designed by a European company and the other was designed by a Japanese company. They had their definitions of Normal (NTP) and Standard (STP) conditions in reverse (Don't ask me who got it right!). This led to inconsistent basis for calculating the mass of hydrogen transferred from one plant to the other.
It is easy to assume that there is an internationally accepted 'standard' for STP or NTP, but this is'nt so. Looking back at your university text books may not help either in this case. You must refer to the design basis of your respective plants.
RR
RE: Conversion between Nm3/hr to Sm3/hr and vice versa
Sm3/hr is the flow taken at 15°C and 1 atm (1,013 barA).
However, the 15°C is sometimes subjected to dicussion: 20°C is taken as well.
Conversion can easily be made by using (P*V)/T = C
Regards, Kingsss
RE: Conversion between Nm3/hr to Sm3/hr and vice versa
RE: Conversion between Nm3/hr to Sm3/hr and vice versa
Temp.: 15 degr C, Press.: 1.01325 bara
THe normal conditions are as follows:
Temp.: 0 degr C, Press.: 1.01325 bara
How to convert between the two in obvious.
regards
RE: Conversion between Nm3/hr to Sm3/hr and vice versa
Those may be your definitions of Standard and Normal but there are many others.
RE: Conversion between Nm3/hr to Sm3/hr and vice versa
These are to my knowledge the widely used conditions, I haven't invented them! So I don't know what you are talking about.
RE: Conversion between Nm3/hr to Sm3/hr and vice versa
Homayun, sorry to tell you that standard and normal conditions have various definitions as katmar says. I suggest you visit the following threads to get an idea of the situation:
Thread124-95060
Thread135-97506
Thread378-90884
Thread378-97454
RE: Conversion between Nm3/hr to Sm3/hr and vice versa
I must admit that it was only relatively recently that I discovered that Normal is not a universal definition. The IUPAC (International Union of Pure and Applied Chemists), which is a well respected organisation, defines it as 100 kPa. Most older books use 101.325 kPa.
Standard conditions are most frequently used in the USA. {/Bait on} I don't want to be rude, but until a few years ago most engineers there didn't know what degrees C were, so they would not have made their definition in those units. I won't tell you what most American engineers think a bar is, but as a hint, the Absolut part is associated with Vodka.{/Bait off}
The bottom line is - the gas conditions need to be defined for every calculation, contract etc where they are used.
regards
Katmar
RE: Conversion between Nm3/hr to Sm3/hr and vice versa
RE: Conversion between Nm3/hr to Sm3/hr and vice versa
The American Gas Association: 60oF (15 5/9oC) and 30 inches (762 mm) of mercury.
The Compressed Gas Institute: 20oC (68oF) and 1 atmosphere.
RE: Conversion between Nm3/hr to Sm3/hr and vice versa
RE: Conversion between Nm3/hr to Sm3/hr and vice versa