Issue 38

F. Majid et alii, Frattura ed Integrità Strutturale, 38 (2016) 273-280; DOI: 10.3221/IGF-ESIS.38.37

Figure 1 : Illustration of pressure vessels elements.

Step

Step detail

Formulas

FP N N C S 1 ( )  

Step3- Full range pressure cycles

(1)

a S N P C S 1 ( ( S N P C C E 1 1 ( ( C C E 1 1 ( ( a

)

P ) 

PN  

Step4- Maximum range of pressure

(2)

)

Step5-Maximum temperature difference between two adjacent points



TN

TN  

)

(3)



ym

a ym S N P T )   TN

Step6-Maximum temperature difference fluctuation between two adjacent points

 

)

(4)

R

Exemption Method B

a C E E 2 1 1 2 2 ( ) ( ( . . )     TM y y S N

Step7-Maximum temperature difference fluctuation for differents components materials

R T  

)

(5)

MLR a S S S N ( )   

Step8- Equivalent stress range

(6)

LT k , 2      S K S )

K S (

e k p k , ,

v k LT k , ,

Elastic Stress Analysis Equivalent stress

(7)



S

)





E

ya k eff k , ,

(8)



S

2

Elastic-Plastic Stress AnalysisEquivalent strain

     

y S



(9)

peq k ,

E

Fatigue Assessment

Table 1 : Pressure vessels fatigue design.

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