Effective length of Elbows 1

[deasdi]

Hi,

I am looking for a online resource to get the effective length of the 90 deg and 45 deg elbows. I need it for the Material - Black Iron or Steel.

Thanks in advance...

 

[MTPipeliner]

http://www.cleandryair.com/fittings.htm

http://www.engineeringtoolbox.com/38_192.html

Both of these have some info you may find useful

 

[onuigbo]

The exact pressure loss through fittings cannot be readily computed because of the geometry of the fittings. However, there is general industry consensus for the equivalent length of fittings in terms of the number of pipe diameters. For a 90 degree elbow, the equivalent length is 30D or 30 times the diameter of the pipe in feet. Hence for a 16 inch long radius elbow, the equivalent length of this elbow is 30 x 16/12 = 40 feet. Of course, if there are 8 elbows in the system, the total equivalent length will be 320 feet.

We deliver steam as if your life depends on it.

 

[pierre80]

hello deasdi,

hereafter you will find a simple method from Idelcik.
You have equivalent length for the elbows, and correction factor following their angle (K) when the ratio (r/d =1.5 )

d (mm) L_equiv (m)
25 0.35
50 0.75
75 1.18
100 1.60
125 2.05
150 2.50
175 2.93
200 3.35
225 3.76
250 4.18
275 4.59
300 5.00
325 5.40
350 5.80
375 6.20
400 6.60
425 7.08
450 7.55
475 8.03
500 8.50

angle(°) K value
0 0
15 0.35
30 0.49
45 0.63
60 0.77
75 0.9
90 1
105 1.07
120 1.15
135 1.22
150 1.28
165 1.3
180 1.35

i.e for a diameter of 100 mm , 90° : the equivalent length is
=L_equiv * K = 1.6m

hope that can help you

Pierre (design and project engineer)

 

[CARF]

Hi Pierre,

Nice table, I will add it to my calculator when I have some time.

Do you have the complete source for me?

Thanks,
CARF

http://www.carf-engineering.com/

 

[pierre80]

Hi Carf,

I've seen your pressure drop calculator.I've done some excel files with various geometries (cylindric, rectangular, diverter, blades obstacles-sinlges or multiples).
I can give you my references regarding your query :

ref :SULZER Boiler Plant Handbook, e/20.12.03 - VII.82 - 5 - Printed in Switzerland, par 8.2, fig32 & 33, p77

Pierre