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GENERAL PIPING DESIGN
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GENERL PIPING DESIGN
Feasibility studyPlans of route:
Environmental considerations.
Safety considerations.
Service conditions:
Substance to be transported.
Pressure, temperature, flow.
Surge conditions (liquid, two phase or dry gas).
Pressure drop, selection of pipe diameter.
Quality plan.
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Why dose the feasibility study isrequired?
Because it is the
procedure todetermine the preliminary design
factor.
Feasibility study
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Feasibility study
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Feasibility study
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Feasibility study
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Feasibility study
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Feasibility study
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GENERL PIPING DESIGN
Preliminary EngineeringDesign factor :
Refinement factor.
Service conditions.
Detailed classification of locations..
Design criteria :
Pressure\temperature design.
Stress criteria.
Expansion and flexibility.
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GENERL PIPING DESIGN
Preliminary EngineeringMaterials :
Selection of pipe wall thickness.
Selection of materials.
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GENERL PIPING DESIGN
Preliminary EngineeringDesign factor:
It is the ratio of the Hoop stress in the pipe at the design
pressure
to the yield stress of the pipe material.
It is a function of:
Design pressure.
Pipe diameter.
Pipe wall thickness.The design factor determines the probability
of a pipeline rupturing
if it has been damaged or is corroded.
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Why dose the preliminary engineering is
required?
Because it is the procedure to determine the
submission for construction authorization.
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Detailed DesignCrossings :
Environmental factors.Crossing design.
Review of design factor.
Pipeline installations :
Pipeline design.
Pressure design.
Equipment selection.
Review of design factor.
Safety systems.Stress criteria.
Expansion & flexibility.
Hazardous studies.
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Corrosion :
External corrosion.
Corrosion survey.
Cathodic protection.
Testing and commissioning :
environmental factors.
Testing plan.
Commissioning plan.
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Why dose the detailed design is required?
Because it is the procedure to make the
project documents.
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DESIGN FLOWCHART
Route Quality Assurance Service Conditions
Crossing
Internal Corrosion
Design Factor
External
Corrosion
Terminals & Stations
Testing &
Commissioning
Materials
Design Criteria
Chosen
Design
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SMYS
0.5% 100%
Plastic
UTS
Strain
St
res
s
YS
Elastic Failure
SMYS
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Design factor ( f )
t d
The pipe wall thickness is a function of:
Design pressure ( P ) t P
Pipe diameter ( d )
Yield strength of the pipematerial ( SY)
fs 1/SY
t (P x d)/SYt = Constant x ( P x d/ SY )
t=1/fx(P x d/ SY)
f =( P x d/ SY x t)
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P
t
d
Hoop stress
Sh= P d / 2t
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P
t
d
Longitudinal stress
Sh= P d / 4t
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API 5L: 1991 SPECIFIED MINIMUM YIELD STRENGTH
SPECIFIED MINIMUM YIELD STRENGTH
lbf/ in2
N/mm2
GRADE OF MATERIAL
B
X42
X46
X52
X56
X60
X65
X70
X80
35000
42000
46000
52000
56000
60000
65000
70000
80000
240
289
317
358
55
386
413
448
482
PIPE MATERIALS
Yield strength
GENERL PIPING DESIGN
