API 570 PREPARATORY COURSE TEASER 1: Design of Pipes for Internal Pressure (Question)
Choose correct pipe schedule for a piping with the following design conditions: Design Pressure
= 400 psig
Design Temperature
= 750 degrees F
M. O. C.
= 8” ND pipes, A 106 gr. B seamless
Corrosion Allowance
= 3.0 mm
Assume standard mill tolerance.
Solution:
P.O. Box No. 7274, Dammam 31462, Saudi Arabia
●
TEL (966) 3 857 0006
[email protected] ● www.gotoITC.com
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FAX (966) 3 857 5255
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API 570 PREPARATORY COURSE TEASER 1: Design of Pipes for Internal Pressure (Solution)
Design Pipe Thickness, tm = PD/2 (SE + PY) + C Here, P = 400 psig -------------------------- given D= 8.625” (219.08 mm)------------- from pipe dimension tables S= 13,000 psi------------------------- Table A-1 (Stress Table) E= 1.0 -------------------------------- Table A-1B (Quality Factor Table) Y= 0.4 -------------------------------- Table 304.1.1 (Y Table) Now, t= 400 x 219.08 / 2 (13,000 x 1 + 400 x 0.4) + 3 = 3.329 + 3 = 6.329 mm Allowing standard negative mill tolerance of – 12.5% Nominal thickness (i.e. ordered thickness) = 6.329 / 0.875 = 7.23 Referring pipe tables again, choose 8” Sch. 40 pipe.
P.O. Box No. 7274, Dammam 31462, Saudi Arabia
●
TEL (966) 3 857 0006
[email protected] ● www.gotoITC.com
●
FAX (966) 3 857 5255
●
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