Matveev Alexey, Ph.D., senior research scientist
Eugenii Shapiro, Ph.D., chief specialist
NTP «Truboprovod», Moscow, Russian Federation
start@truboprovod.ru
http://www.truboprovod.ru
1
START Prof – THE PIPE FLEXIBILITY AND STRESS ANALYSIS
World’s first pipe stress analysis software
First introduced in 1969
The Russian code pipe stress analysis de facto standard
Year
1969
1972
1976
1992
2000
2013
Machine/operating system
Minsk 2 computer
Minsk 32 computer
ES-1040 computer
PC: MS DOS
PC: Windows 95
PC: Windows 8
2
START implements Russian codes
Code
STO 10.001-2009
Detail
District heating networks
RD 10-249-98
SA 03-003-07
Power piping
Process piping
SNIP 2.05.06-85
&
SP 36.13330.2012
STO 91579448-01.12013
Gas & oil transmission
and distribution piping
systems
Fiberglass district
heating pipelines (based
on ISO 14692)
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START is used by more than 1400 companies,
more than 8300 licenses
Russia, Ukraine, Belarus, Kazakhstan,
Turkmenistan, Uzbekistan, Lithuania, Czech Republic, Serbia, Finland, Germany, United Kingdom
Belarus
Ukraine
Russia
Kazakhstan
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Some completed design projects from one of our 1400 users: OAO "Mosinjproject", Moscow, Russia.
Buried district heating network with polyurethane foam insulation built in Moscow. Depth 1.4 m, soil: sand,
diameter 1420 mm, wall thickness 14 mm, Pressure 1.6 MPa, Temperature 130°C, product: hot water.
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OAO "Mosinjproject", Moscow, Russia.
Above ground district heating network with polyurethane foam insulation built in Moscow. Diameter 1420
mm, wall thickness 14 mm, Pressure 1.6 MPa, Temperature 150°C, product: hot water
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OAO "Mosinjproject", Moscow, Russia.
Buried district heating network with polyurethane foam insulation at Moscow. Depth 2 m, soil: sand, diameter
820 mm, wall thickness 9 mm, Pressure 1.6 MPa, Temperature 130°C, product: hot water
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START buried pipeline modeling
The pipe-soil interaction model is based on the experiment
results by VNIIST Co., Moscow
Interaction between pipeline and soil in buried pipelines, taking
into account nonlinear soil flexibility, polyurethane insulation
layer and expansion cushions.
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Buried pipeline soil interaction model
Backfill trench soil
 K1 – Polyurethane foam insulation flexibility
 K2 – Expansion cushion flexibility
 K3 – Horizontal soil flexibility
 K4 – Vertical soil flexibility
 K5 – Longitudinal soil flexibility
Cushion
Native 9soil
Buried pipeline – soil interaction model
The pipe-soil interaction model is based on the experimental results at VNIIST, Moscow
Vertical soil flexibility
Longitudinal soil flexibility
Horizontal soil flexibility
Horizontal soil P-∆
diagram
Vertical soil P-∆
diagram
Friction
Longitudinal soil P-∆
diagram (friction)
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START automatically calculates the soil spring properties according to
the soil type, depth at each point, slope angle of pipe and ground,
insulation properties
The spring properties is based on
horizontal pipe experiment data.
START use the special algorithm
to recalculate the nonlinear spring
properties for pipes for a different
slope angle 0 to 90 degree.
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START also consider the buoyancy of water and changing of the
soil properties located in water (soil liquefaction)
Ground water level
Ground water level
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START also checks the buried pipe crossection for
 Bending and membrane stresses in pipe due to
external soil pressure and internal product pressure
 Ring buckling of pipe cross section
 The stresses in polyurethane foam insulation
It’s possible due to the internal nonlinear FEM
model of buried pipe crosssection with
polyurethane. This model consider:
 Nonlinear soil springs around the pipe ring
 Pressure swell effect (prevents ovality)
 Detachment of soil at upper side of pipe
(soil should work only for compression)
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Buried pipe with polyurethane insulation depth selection problem
The maximum depth is limited by the polyurethane foam
insulation strength analysis and ring buckling of the pipe
The minimum depth is limited by longitudinal stability (stability
increases as the depth increases)
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Code strength conditions comparison for buried heating networks
Load case
1 Pressure
load
ASME B31.4-2012
Restrained
4 Expansion
load (T1-T2)
S H  0.72( E )SY
S H  ( E )Sh
S H  PD / 2t
S H  PD / 2t
Sh  min(SY / 1.5; ST / 2.4)
Seq  1.1Sh
S L  0.75SY
S L  0.5S H  iM / Z  Fa / A
2
Seq  S H
 S H S L  S L2  3St2
S H  P( D  t ) / 2t  Sb, soil weight
S L  ( to 0.5*)S H  ia Fa / A  Sb
S L  0.9 SY
S L  S E  S H  M / Z  Fa / A
Sb  0.8 (ii M i ) 2  (io M o ) 2 / Z
St  it M t / 2Z
2
S eq  S H
 S H S L  S L2  3St2
Seq  1.5Sh (only for pipes: ii , io , it , ia  1)
S eq  0.9 SY
S E  0.9SY
S E  E (T1  T2 )
S E  S A  f 1.25( S h  Sc )  S L 
S L  0.9SY
S L  S E S H  M / Z  Fa / A
Fa includingS E  E (T1  T2 ) in 3 & 4 case
For carbon steel:
S E  Sb2  4St2
Seq  18720/ N 2  129
Sb  (ii M i ) 2  (io M o ) 2 / Z
Seq  11840/ N 2  258
St  M t / 2 Z
Seq  1.5( S h  Sc )
f  6 / N 0.2
5 Occasional
Short-Term
Loads
STO 10.001-2009 & GOST 555962013 adopted to ASME designations
S H  0.72( E )SY
2 Sustained
Excluding
Thermal
Loads (T1)
3 Sustained
Including
Thermal
Loads (T2)
ASME B31.4-2012
Unrestrained
0.3  f  1.2
S L  0.8SY
P, Fa , M i , M o , M t is stress range
Seq  1.9Sh (only for pipes: ii , io , it , ia  1)
S L  0.5S H  iM / Z  Fa / A
* - Calculates automatically due to design of pipeline. For example ν=0.3 for fully restrained pipe, 0.5 for fully
unrestrained and 0.3…0.5 for other intermediate design
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Weight + pressure + Temperature case is checked only for straight pipes to avoid the yield
of pipe material. For bends, tees and reducers this condition is ignored
 eq  1.5Sh
“Fatigue fracture”
check case
k
N 0i
 1, i  1,2,, k



N
i1
0 i
=
Seq  18720/ N 2  129
Seq  11840/ N 2  258
Seq  1.5( S h  Sc )
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START consider the remaining friction forces at the cold condition of the pipeline.
No analog in other software. It is important for pre-stretched buried pipelines
Operation condition of
above ground pipeline
Cold condition of above ground
pipeline (after cool down).
There’s a big anchor force due
to remaining friction
Operation condition of
buried pipeline
Cold condition of buried
pipeline (after cool down).
There’s a big anchor force due
to remaining friction
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START consider pressure thrust forces
Bourdon effect in bends with initial ellipticity (ovality)
Pipe contraction (shortening) due to internal pressure
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Since 2014 START perform stress analysis for fiberglass piping with polyurethane
foam insulation according to standard STO 91579448-01.1-2013 (copy of ISO
14692) for district heating pipelines.
START have the database with fiberglass pipe and fitting material properties at
different temperatures. Therefore START provides fiberglass analysis as easy as
for the steel pipelines.
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Unrestrained buried pipeline modeling
Virtual Anchors
Axial forces diagram
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Buried pipeline model with restrained zone
Virtual anchor length
(sliding friction zone)
Restrained Zone (zero displacement)
Axial forces diagram
Lateral bearing length
Bending moment diagram
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START consider nonlinear effects

Friction in sliding supports

Returning force due to hanger rod rotation

One-way restraints

Gaps

Nonlinear soil properties for buried pipes

Spring and constant force hanger selection
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Equipment and vessel nozzle flexibility modeling:
•
START-Nozzle option
•
Nozzle-FEM program
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START offers
 Input data error checking and reports. The error checker analyzes the
user input and checks for consistency from both engineering and
geometrical point of view
 Automatic on-the-fly pressure design checking of all pipes and fittings
 Regular training by our specialists that can be provided at your site or
in one of our training centers
 Technical support from START developers
 Exports input data and analysis results to Microsoft Word
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Pricing Options
Option
START-Soil
Detail
Analysis of buried pipelines and polyurethane
insulation stress
START-Projected life Projected life analysis of designed process
pipelines considering fatigue strength and corrosion
per SA 03-003-07
START-Nozzle
Equipment and vessel nozzle flexibility calculation
per WRC-297 and BS-5500
СТАРТ-PCF
Imports pipeline models from PCF format files
(provided by CEA Plant4D, Bentley AutoPlant,
PlantSpace, Autodesk Plant3D, Coade CADWorx,
Intergraph SmartPlant and other systems)
START–Neutral file
Import from the neutral format file, export of input
data and analysis results to the neutral file. Neutral
file is a text file for data exchange with other
software
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• Sliding support span calculation (strength condition
and limited sagging condition)
• Wall thickness calculation of pipes, bends, tees,
redusers, caps
• Draft L-, Z-, U-shaped loop analysis
• One-time compensator span length calculation
• Restrained buried straight and curved pipe
longitudinal stability analysis
• Pipe ring buckling due to external pressure analysis
• Pipe ring buckling and stress analysis due to soil
weight
• Polyurethane insulation stress analysis due to soil
and vehicle weight
• e.t.c.
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Thank you!
Matveev Alexey, Ph.D., senior research scientist
Eugenii Shapiro, Ph.D., chief specialist
NTP «Truboprovod», Moscow, Russian Federation
start@truboprovod.ru
http://www.truboprovod.ru
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