Pipe wall thickness calculation as per ASME B31.4

PIPE WALL THICKNESS CALCULATION FOR 48" CRUDE EXPORT PIPELINE
	Minimum Wall Thickness Calculation as per ASME B31.4 para. 404.1
1	General
	The required thickness of pipe shall be equal to or greater than tn determined
	in accordance with the following equation
	tn  =  t  + A                                                          (1a)
2	Nomenclature
	tn ; Nominal wall thickness satisfying requirements of pressure and allowance
	Pi ; Internal design gauge pressure (psig)
	D  ; Outside diameter of Pipe (in)
	S  ; applicable allowable stress value (psi)
	CA ; Corrosion allowance (in)
	A  ; Additional thickness ; the sum of mechanical allowances
	(threading or grooving) plus corrosion allowances (in)
	t  ; Pressure design thickness Only (in)
	t = (Pi x D) / (2 x S)                                        (2a)
3	Calculation
	1)  CODE                                       ASME B 31.4
	2)  Design Data
	- Material Spec.               :       API 5L Gr. X52   SAW
	- Design Condition           :              Temperature  200  0 F
		Pi  = 850 Psi g
		CA = 0.125 inch		=    3.2 mm
		A  =  0  +  CA = CA = 0.125 inch
		S   = 37450 Psi
	3)  Result
	NPS (in)	48
	(D) Outside dia (in)	48
	(S) Allowable Stress (Psi)	37450
	(t) Thickness as per Eq. (2a)	0.5447
	(A) Additional Thickness	0.125
	(tn) Reqd. Min. Thk. = (t) + (A)	0.6697
	Selected Nominal Thickness (in)	0.6880

Beam design details for laterally unsupported

Laterally Unsupported Beam Design

calculating  Bending Moment (M=W* x L2 / 8) 

                   Shear Force(V = W* x L / 2)

                   Section Modules(Z = M /(σbc or σbt))

Calculated Average Shear Stress ( ζva = V /(h x Tw))

Permissible Shear Stress(ζv = 0.4 x fy)

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