63
I-800
Example:
How much expansion can be expected in a 200-foot run of 2-inch Victaulic Fire-
Lock CPVC Sprinkler System Pipe, and how long should the expansion loop be to compen-
sate for this expansion (the expected temperature range will be from 40°F to 110°F)?
First Find:
Δ
T = (Change in Temperature)
Δ
T = T2 - T1
Δ
T = 110°F - 40°F
Δ
T = 70°F
To Find:
Δ
L = (Amount of Expansion in inches from Table III)
Δ
L =
Δ
L of 160 ft with a
Δ
T of 70°F +
Δ
L of 40 ft. with a
Δ
T of 70°F
Δ
L = 4.30" + 1.08"
Δ
L = 5.38"
— OR —
Δ
L = 12 eL (
Δ
T)
e = 3.2 x 10-5 (from Table II)
L = Length of Run in Feet
Δ
T = Change in Temperature in °F
Δ
L = 12 x .000032 x 200 x 70
Δ
L = 5.38"
l
=
l
= Length of Expansion Loop in inches
E = Modulus of Elasticity at 110°F (Table I)
D = Average O.D. of Pipe
Δ
L = Change in Length of Pipe Due to Change in Temperature
S = Working Stress at 110°F (Table I)
To find the length of the expansion loop or offset in inches
l
=
l
= Length of Expansion Loop in inches
E = Modulus of Elasticity at maximum temperature from Table I
D = Average Outside Diameter of the pipe from Table IV
S = Working Stress at maximum temperature from Table I
Δ
L = Change in Length of pipe due to change in Temperature from Table III
l
=
l
=
l
= 70.2"
3ED
Δ
L
(
)
2S
------------------
3ED
Δ
L
(
)
2S
------------------
3
346 000
2.375
5.38
×
×
,
×
2
1345
×
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4931
I-800 2755 Rev_I.fm Page 63 Tuesday, September 13, 2005 8:46 AM
