8/18/2019 Some Basic Formulae for Piping

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Some Basic Formulae for Piping

Length of leg to absorb thermal expansion

∆=   D L   66

D= Diameter (mm or in)Δ = Expansion (mm or in)

)(12   T T  Lo   −=∆   α 

A Conservative formula for external pressure alulations (a long pipe un!er external

 pressure)

( ) "2

  #)1("

2 Dt 

 E  P 

all 

ν −=

E = Elasti $o!ulus % = &oisson's ratio

Axial uling *tress

 D Et S all 

  #12+,-=

.ui!e! Cantilever eam /ormula

∆="

12

 L

 EI  F 

∆==2

6

2   L

 EI  FL M 

en!ing stress

 I 

 MD

 Z 

 M S 

2==

( )0060

  io  D D I    −=

  π  

Allo1able *pan base! on stress

w ZS  L   #1-=

1here * = allo1able stress2 3 = *etion mo!ulus2 1 = 1eight !ensit4

Allo1able *pan base! on sagging

0 #125   w EI  L   ∆=