Crane #410 has 400% more friction factor. Why?
Crane #410 has 400% more friction factor. Why?
(OP)
Crane #410 has 400% more friction factor in the "fiction factors versus Reynold #" table. Does anyone know why?
I compared the Crane #410 table to the Moody, Trans. ASME 66, 671 [1944] friction factor table. This table is located in the Perry's Chemical Engineering Handbook in the Fluid and Particle Dynamics section.
How I found the discrepancy is as follows:
- My frictional factors, calculated by the Churchill equation, were 4 times smaller than the Crane #410 table.
- The Laminar flow region in one table says f=16/Reynolds # and another say f=64/Reynolds #.
Therefore, why is Crane #410 400% more stringent than the college texts. What are you thoughts?
I compared the Crane #410 table to the Moody, Trans. ASME 66, 671 [1944] friction factor table. This table is located in the Perry's Chemical Engineering Handbook in the Fluid and Particle Dynamics section.
How I found the discrepancy is as follows:
- My frictional factors, calculated by the Churchill equation, were 4 times smaller than the Crane #410 table.
- The Laminar flow region in one table says f=16/Reynolds # and another say f=64/Reynolds #.
Therefore, why is Crane #410 400% more stringent than the college texts. What are you thoughts?





RE: Crane #410 has 400% more friction factor. Why?
Therefore I suggest you look at the relevant pressure drop equations to see if they give the same results.
RE: Crane #410 has 400% more friction factor. Why?
They confused everything for people like me. For example, if I use Perry's Chemical Engineering Handbook and they use Crane #410, we would produce the same friction loss equation numbers but different frictional factor constants.
RE: Crane #410 has 400% more friction factor. Why?
David
RE: Crane #410 has 400% more friction factor. Why?
Best regards
Morten
RE: Crane #410 has 400% more friction factor. Why?
Good luck,
Latexman
RE: Crane #410 has 400% more friction factor. Why?
(I can say that because I am both of the above.)
Regards,
SNORGY.
RE: Crane #410 has 400% more friction factor. Why?
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RE: Crane #410 has 400% more friction factor. Why?
If I'm not mistaken, the 4 stems from the simple fact that the shear stress between the conduit's wall and the fluid was originally estimated for a circular cross-section (as for tubes and pipes) with a value of πD2/4.
RE: Crane #410 has 400% more friction factor. Why?
The graphs in Crane #410 (A-24 and A-25) are for Moody Friction factor, which is 4 times Fanning friction factor. That is, f = 64/Re is Moody and f = 16/Re is Fanning.
Be careful. It is easy to mix the two and calculate 400% greater (or 25% less) head loss. The calculation for head loss in feet is:
using Moody Friction factor -
h(friction) = f(M) * (L/D) * v^2 / (2 * g)
using Fanning Friction factor -
h(friction) = 4*f(F) * (L/D) * v^2 / (2 * g)
where,
f(M) = Moody Friction factor
f(F) = Fanning Friction factor
L = length in feet
D = pipe inside diameter in feet
v = velocity in ft/s
g = 32.174 ft/s^2, acceleration due to gravity
The Colebrook-White equation is an iterative method that calculates Fanning friction factor.
f(F)^2 = 1 / ( -4 * Log(eps / (3.7 * D) + 1.256 / (Re * √f(F) )
where,
eps = pipe roughness in feet
Re = Reynold's number
RE: Crane #410 has 400% more friction factor. Why?
See FAQ124-1746: What is the difference between Fanning and Moody friction factors?