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Title: Nitrogen Distribution System (79720-PS-104 & 79720-PS-105) Stress Analysis
Note Number: 79720-P0002
Author(s): Connor Kaufmann Page 1 of 24
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Nitrogen Distribution System
(79720-PS-104 & 79720-PS-105)
Stress Analysis
Revision History:
Revision Date Released Description of Change
NA Do Not Use Original release, Issued for Project use
Draft
Connor Kaufmann
JLab Cryogenics Group
Mechanical Engineer
Nate Laverdure
JLab Cryogenics Group
Pressure Systems Design Authority
Hongyu Bai
SLAC Accelerator Directorate
Cryogenics Integration Group Leader
Mike Bevins
JLAB Mechanical Engineering
Cryogenics Plant Deputy CAM
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Note Number: 79720-P0002
Author(s): Connor Kaufmann Page 2 of 24
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Table of Contents
1.0 Introduction ............................................................................................................................................ 3 2.0 Scope ...................................................................................................................................................... 3 3.0 Piping Design Parameters ...................................................................................................................... 7 4.0 Analysis.................................................................................................................................................. 9 5.0 Piping Evaluation ................................................................................................................................. 18 6.0 Flange Evaluation ................................................................................................................................ 21 7.0 Equipment Nozzle Evaluation ............................................................................................................. 21 8.0 Support Evaluation ............................................................................................................................... 22 9.0 Associated Analyses / Documents ....................................................................................................... 22 10.0 Summary / Conclusions ..................................................................................................................... 22 11.0 References .......................................................................................................................................... 22 Appendix A – AutoPIPE Models / Reports ................................................................................................ 24
Pressure System Documentation-Calculations
Title: Nitrogen Distribution System (79720-PS-104 & 79720-PS-105) Stress Analysis
Note Number: 79720-P0002
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1.0 Introduction
The purpose of this Engineering Note is to document the analysis that was performed to ensure
the LCLS-II Cryoplant Nitrogen Distribution System piping design is suitable for all operating
and occasional loads.
This report discusses the piping scope (Section 2), the piping design parameters (Section 3), the
basis of the analysis that was performed (Section 4), evaluation of the various piping system
components (Sections 5 through 8), associated analyses / documents (Section 9) and the
summary / conclusion (Section 10).
2.0 Scope
The scope of this analysis consists of the liquid Nitrogen (LN2) “fill line” piping that extends
from the tank farm external fill station to the storage Dewars as well as the “withdrawal line”
LN2 piping that travels from the storage Dewars to end use on the North Slab (upper cold boxes,
purifier, vaporizer etc.) The scope also includes the gaseous Nitrogen (GN2) distribution lines
which have outlets across the entire North Slab.
This scope is shown in Figures 1-4 and the drawings listed below.
Drawing
Number Drawing Title
Drawing
Revision
Drawing
Type
79720-2000 LCLSII LN2/GN2 Distribution System - P&ID
79720-2032 LN2 Intake and Distribution Piping
Arrangement - Piping
79720-0033 LN2 Intake Line Pipe Spool - Piping
79720-2044 LN2 Filling Port - Piping
79720-0034 LN2 Distribution Line Spool - Piping
79720-2400 GN2 Distribution Piping Arrangement - Piping
79720-2401 GN2 Vaporizer Spool - Piping
79720-2402 GN2 Distribution Spool - To Purifier - Piping
79720-2403 GN2 Purge Spool – ½ MNPT - Piping
79720-2404 GN2 Purge Spool – 1 MNPT - Piping
79720-2405 GN2 Pipe Header Spool - Piping
79720-2406 GN2 Distribution – To Inside CR1 - Piping
79720-2407 GN2 Distribution – To Outside CR1 - Piping
79720-2408 GN2 Distribution – To CBX Room East - Piping
79720-2409 GN2 Distribution – To CBX Room West - Piping
79720-2410 GN2 Distribution – To Outside CR2 - Piping
79720-2411 GN2 Distribution – To Inside CR2 - Piping
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Title: Nitrogen Distribution System (79720-PS-104 & 79720-PS-105) Stress Analysis
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Figure 1: Nitrogen Distribution System (LN2 Tank Farm Piping)
LN2 Storage Dewars
LN2 Fill Station
LN2 Fill Station
LN2 “Fill Line”
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Figure 2: Tank Farm Piping LN2 Fill Station
Figure 3: Tank Farm LN2 Piping Fill and Withdrawal Lines
Figure 4: North Slab LN2 Piping
LN2 Storage Dewars
LN2 “Withdrawal Line”
LN2 “Fill Line”
CP2 Cold Box
CP1 Cold Box
To Tank Farm
Vaporizer
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Figure 5: North Slab GN2 Piping
Figure 6: North Slab GN2 Outlets (Indoor and Outdoor)
Vaporizer
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3.0 Piping Design Parameters
All piping is designed in accordance with ASME B31.3 Process Piping, 2014 Edition [1] and
local requirements. These local requirements include the 2013 California Building Code (CBC)
[2], its reference standard ASCE 7-10 [3], the 2013 California Mechanical Code (CMC) [4] and
the Cryogenic Plant Seismic Design Criteria [5]. The vacuum jacket for the liquid Nitrogen line,
is technically excluded from B31.3 standards, however the code is applied whenever practical.
The pressure-temperature design parameters for each of the lines is summarized below.
Line
Minimum Design
Metal Temperature
(°F)
Design
Temperature
(°F)
Design
Internal
Pressure
(psig)
Design
External
Pressure
(psig)
LN2 Process -320 100 145 0
LN2 Jacket -20 120 14.7 -14.7
GN2 -20 120 145 0
The size, material, schedule / rating and other pertinent properties for each piping component is
specified on the design drawings. The general properties for each of the lines are summarized
below.
Line Gen. Pipe
Size Pipe Materials
Pipe
Schedule(s)
Flange
Rating
LN2 Process 1.5 NPS ASTM
A312-TP304/304L Sch. 10S NA
LN2 Jacket 4 NPS ASTM
A312-TP304/304L Sch. 5S NA
GN2 2 NPS ASTM
A312-TP304/304L Sch. 10S NA
The pipes are assumed to be electric fusion welded tubes with a single butt seam (Basic Quality
Factor, Ej, of 0.8 per Table A-1B in B31.3). All other A312 pipe fabrication methods with
higher quality factors are therefore acceptable.
In addition to operating conditions, the piping is designed for occasional loads (seismic, wind).
The applied seismic loads and load combinations are determined in accordance with the 2013
CBC and ASCE 7-10.
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Per the LCLS-II Cryogenic Building Geotechnical Report [6] and the Cryogenic Plant Seismic
Design Criteria, the site seismic design parameters include Site Class C, SD1 = 1.012 and SDS =
1.968.
The substances used in the LCLS-II Cryoplant and these lines (namely inert cryogenics, gaseous
helium) are not hazardous (highly toxic or explosive / flammable) in accordance with CBC Table
307.1 and the Cryogenic Plant Seismic Design Criteria. Thus, per ASCE 7-10 Table 1.5-1 and
the Cryogenic Plant Seismic Design Criteria, the Risk Category for the Cryogenic Building and
its associated components is II. Per ASCE 7-10 Table 1.5-2 and the Cryogenic Plant Seismic
Design Criteria, the Seismic Importance Factor for the Cryogenic Building and its associated
components is Ie = 1.0. Per ASCE 7-10 11.6 and the site seismic design parameters (S1 = 1.168),
the Seismic Design Category for the Cryogenic Building and its associated components is E.
As the piping is a nonstructural component, the seismic design force is determined in accordance
with ASCE 7-10 13.3.1 as demonstrated below. The component amplification factor, ap, is 2.5 in
accordance with ASCE 7-10 Table 13.6-1. Except for rare exceptions the piping joints are
welded. Thus, per the Cryogenic Plant Seismic Design Criteria, the component response
modification factor, Rp, is reduced from 12 to 6. To further improve seismic performance, the
component importance factor, Ip, is taken as 1.5 even though not required by ASCE 7-10 13.1.3.
• 𝐹𝑝 =0.4(𝑎𝑝)𝑆𝐷𝑆
𝑅
𝐼𝑝
(1 + 2𝑧
ℎ) 𝑊𝑝 =
0.4(2.5)1.9686.0
1.5
𝑊𝑝 = 0.492 (1 + 2𝑧
ℎ) 𝑊𝑝 (13.3-1)
• 𝐹𝑝𝑚𝑎𝑥= 1.6 𝑆𝐷𝑆𝐼𝑝 𝑊𝑝 = 1.6(1.968)(1.5)𝑊𝑝 = 4.724 𝑊𝑝 (13.3-2)
• 𝐹𝑝𝑚𝑖𝑛= 0.3 𝑆𝐷𝑆𝐼𝑝 𝑊𝑝 = 0.3(1.968)(1.5)𝑊𝑝 = 0.89 𝑊𝑝 (13.3-3)
• So, 𝐹𝑝 = 0.89 𝑊𝑝 for piping supported at the base (z = 0)
For piping connected higher than 40% of the structural height (z = height of point of attachment,
h = average height of structure), the seismic design force is increased according to equation 13.3-
1. For the rare threaded piping sections / components, the component response modification
factor, Rp, is reduced from 6 to 3 in the spirit of the Cryogenic Plant Seismic Design Criteria.
In this system, most piping is base supported. In accordance with 13.3-1, the seismic force the
seismic force applied to the Fill Station piping and some piping within the North Slab is
increased by a factor of 1.66 (z/h = 1).
To meet the requirement that the seismic force is applied in the direction that produces the most
critical load effect, 100% of the seismic design force is applied in one horizontal direction and
30% of the seismic design force is applied in an orthogonal direction (ASCE 7-10 12.5.3.1). In
Pressure System Documentation-Calculations
Title: Nitrogen Distribution System (79720-PS-104 & 79720-PS-105) Stress Analysis
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addition, a vertical seismic force of ±0.2 SDS Wp is also simultaneously applied. All directional
combinations are applied (i.e. +100% X, -Y, -30% Z; -30% X, +Y, +100% Z; etc). The design
load combinations / factors in which these forces are applied are discussed in Section 4.
As with the seismic design force, the wind design force is determined in accordance with the
2013 CBC and ASCE 7-10. As discussed / derived previously, the Risk Category for the
Cryogenic Building and its associated components is II. As such, per Figure 26.5-1A in ASCE
7-10, the basic wind speed is 110 miles per hour (mph). In accordance with ASCE 7-10 26.7.2 /
26.7.3, the exposure category for the piping is C (the same as the Cryogenic Building).
The design wind load is determined in accordance with ASCE 7-10 29.5 as demonstrated below.
The gust-effect, G, is 0.85 in accordance with ASCE 7-10 26.9.1. The effect on wind speed from
upstream isolated hills, ridges, etc is considered negligible, so the topographic factor, Kzt, is 1.
As the pipe is round, the wind directionality factor, Kd, is 0.95 in accordance with Table 26.6-1.
As all pipe in this scope is less than 15 feet above the ground, the velocity pressure exposure
coefficient, Kz, is 0.85 in accordance with ASCE 7-10 Table 29.3-1. As D√(qz), see below, is
less than 2.5 for all pipes in this scope, the force coefficient is conservatively taken to be 1.2 (in
accordance with ASCE 7-10 Figure 29.5-1).
• 𝐹 = 𝑞𝑧𝐺𝐶𝑓 (𝑙𝑏/𝑓𝑡2) (29.5-1)
• 𝑞𝑧 = 0.00256 𝐾𝑧𝐾𝑧𝑡𝐾𝑑𝑉2 = 0.00256(0.85)(1)(0.95)(110)2 = 25.1 (29.3-1)
• 𝐹 = (25.1)(0.85)(1.2) = 25.52 (𝑙𝑏/𝑓𝑡2)
• 𝐹𝑚𝑖𝑛 = 16.00 (𝑙𝑏/𝑓𝑡2) (29.8)
• So, 𝐹 = 25.52 (𝑙𝑏/𝑓𝑡2)
To meet the requirement that wind shall be assumed to come from any horizontal direction with
no account for shielding for other structures (CBC 1609.1), the wind is applied in eight
horizontal directions (0°, 45°, 90°, 135°, etc). The wind vertical uplift force is considered
negligible for this piping scope. The design load combinations / factors in which the horizontal
forces are applied are discussed in Section 4.
For the inner LN2 process line, wind loads are not applied, since this load is only experienced by
the outer vacuum jacket pipe. Also, a significant portion of both the LN2 jacket and the GN2
pipe are located inside the cryoplant building (e.g. shielded from wind), this is ignored for the
analysis.
4.0 Analysis
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Title: Nitrogen Distribution System (79720-PS-104 & 79720-PS-105) Stress Analysis
Note Number: 79720-P0002
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The piping is analyzed using Bentley AutoPIPE Version 10. To evaluate piping for the design
parameters discussed in Section 3, the models inputs are as described below.
Pressure –Temperature Cases
Case 1 Case 2 Case 3 Case 4
Pressure Max Max Vacuum* Max
Temperature Max Min Install Max
LN2 Process LN2 Jacket GN2
P (psig) T (oF) P (psig) T (oF) P (psig) T (oF)
Case 1 145 100 15 120 145 120
Case 2 145 -320 15 -20 145 -20
Case 3 0 70 0 70 0 70
Case 4 145 100 15 120 145 120
Also, since precise thermal expansion/contraction is available for 304/304L stainless steel at
cryogenic temperatures from the NIST Cryogenic Material Properties Database the linearized
default data in Autopipe is replaced with more accurate representations.
NIST Thermal Contraction Data
Parameter LN2 Process LN2 Jacket GN2 Unit
Min Design Metal Temperature -320 -20 -20 oF
Max Design Metal Temperature 100 120 120 oF
Thermal Contraction Rate -3.35 -0.89 -0.89 in/100ft
Thermal Expansion Rate 0.35 0.56 0.56 in/100ft
*Rate Relative to 70oF Reference Temperature
Notes:
1. The install/rest temperature is assumed to be 70°F (55oF is the average
expected daytime temperature in Palo Alto during November through March,
but 70oF gives a more conservative temperature range for thermal
contraction).
2. As AutoPIPE does not impose pressures below 0 psig, Case 3 is inherently a
gravity check. A separate evaluation is discussed in Section 5.
3. The purpose of Case 4 is to evaluate the system during a pressure relief event
(i.e. apply the relief valve discharge reaction force).
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Equipment/Dewar Nozzles
The nozzles are modeled as pipe to the shell to nozzle junction. This junction is
modeled as a nozzle flexibility element, to reflect the flexibility of the junction,
followed by a rigid anchor. The loads on the rigid anchor are compared to the
allowable nozzle loads.
Anchor movement due to thermal expansion / contraction of the tank and seismic
/ wind displacement of the tank (as required by ASCE 7-10 15.7.4) is considered.
Negligible anchor movements (less than 1/32”) are not included in the model.
Relief Valve Reaction Force
The relief valve discharge reaction forces as calculated are applied to Case 4.
Friction
In calculating pipe stresses, nozzle loads and pipe displacements, friction are
conservatively ignored. In calculating support loads (LRFD cases), friction is
considered. The steel-to-steel coefficient of friction at the U-bolt and pipe strap
supports is assumed to be 0.5. For the G-10CR spacers, the friction coefficient is
assumed to be 0.2.
Supports
In accordance with the design, U-bolts are modeled to reflect a loose installation.
In other words, a gap of 1/2 the difference between the inner U-bolt dimension
and the pipe outer diameter on both sides and above the pipe is included. The
Unistrut pipe straps are modeled with no gaps. Like anchors, the supports are
modeled as rigid. The loads on the rigid supports are compared to the allowable
support loads and used as inputs in the separate structural analysis. Spacers are
modelled having the as designed 1/16” radial gap movement, and are treated with
the friction values in the above section.
Flexible Hoses
Flexible hoses are used throughout the cold liquid Nitrogen lines in order to
accommodate thermal contractions in the process lines. Hoses are assumed to be
completely rigid in the axial and torsional directions, and are assigned a negligible
stiffness value in the other four degrees of freedom.
Flanges
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Flanges are checked for leak tightness using the conservative equivalent pressure
method. This method, defined in the obsolete Nuclear Piping Code (ASME
B31.7) paragraph 1-704.5(a), is summarized in the equation below (from
AutoPIPE) where P is the line pressure, M is the external bending moment, F is
the external axial tension force and G is the gasket reaction diameter.
𝑃𝑇𝑜𝑡𝑎𝑙 = 𝑃 + 𝑃𝑒𝑞
𝑃𝑇𝑜𝑡𝑎𝑙 = 𝑃 + 16𝑀
(𝜋𝐺3)+
4𝐹
𝜋𝐺2
To reduce the conservatism of this approach to a more reasonable level, the total
calculated pressure is compared to 110% of the ASME B16.5-2013 [11] flange
pressure rating for normal design operating conditions and 150% (equal or less
than the flange hydrotest pressure) for occasional operating conditions.
Some of the flanges used are not standard ANSI Pressure Class, and are qualified
by additional calculations as required by code. These flange calculations are
located in the components calculation report.
Combinations
The design load combinations are specified in ASME B31.3 and ASCE 7-10
2.3.2. While the pipe is designed using allowable stress design, some support
components (support anchors for example) are designed based on strength design.
As the pipe snow, rain and live loads are zero, the four potential allowable stress
determining load combinations are, in accordance with ASCE 7-10 2.4.1 and
12.4.2.3, below. Note that ρ = 1 per ASCE 7-10 13.3.1 and pressure (P) and
temperature (T, expansion from ambient / install temperature to case temperature)
apply to all load combinations.
5a. (1.0 + 0.14 SDS) D + 0.7ρQE + P + T
5b. (1.0) D + 0.6W + P + T
7. (0.6) D + 0.6W + P + T
8. (0.6 - 0.14 SDS) D + 0.7ρQE + P + T
The five potential strength determining load combinations are, in accordance with
ASCE 7-10 2.3.1 and 12.4.2.3, below. Note that ρ = 1 per ASCE 7-10 13.3.1 and
pressure and temperature loads apply to all load combinations.
1. (1.4) D + P + T
4. (1.2) D + 1.0W + P + T
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5. (1.2 + 0.2 SDS) D + ρQE + P + T
6. (0.9) D + 1.0W + P + T
7. (0.9 - 0.2 SDS) D + ρQE + P + T
The ASME B31.3 code required combinations are below.
Hoop Pressure
Sustained Gravity + Pressure
Expansion Minimum to Maximum Temperature
Expansion Ambient / Install Temperature to Case Temperature
Occasional Sustained + Earthquake
Occasional Sustained + Wind
The table below summarizes the load combinations applied to the various pipe
system components. Each load combination is applied in all applicable directions
/ direction combinations. Note that the ASCE load combinations are applied to
pressure-temperature Case 1 (maximum pressure, maximum temperature). The
inclusion of thermal expansion stresses in the ASCE 7-10 occasional load cases is
significantly more conservative than required by code.
Combination Component Allowable
Limit Reference
Hoop Pipe Stress Ej x S 304.1.2
Sustained Pipe Stress S 302.3.5(c)
Expansion – Max Pipe Stress SA 302.3.5(d)
Expansion – Cases 1-4 Pipe Stress SA 302.3.5(d)
Occasional – Earthquake Pipe Stress 1.33 S 302.3.6
Occasional – Wind Pipe Stress 1.33 S 302.3.6
Gravity + Pressure +
Temperature (Cases 1-4) Flange Pressure 1.1 F See above
ASCE 7-10 – Stress 5a
Pipe Stress 1.33 S 302.3.6
Pipe Displacement NA
Flange Pressure 1.5 F See above
Nozzle Loads Per Fabricator
U-Bolts Per Manufacturer
ASCE 7-10 – Stress 5b
Pipe Stress 1.33 S 302.3.6
Pipe Displacement NA
Flange Pressure 1.5 F See above
Nozzle Loads Per Fabricator
U-Bolts Per Manufacturer
ASCE 7-10 – Stress 7 Pipe Stress 1.33 S 302.3.6
Pipe Displacement NA
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Flange Pressure 1.5 F See above
Nozzle Loads Per Fabricator
U-Bolts Per Manufacturer
ASCE 7-10 – Stress 8
Pipe Stress 1.33 S 302.3.6
Pipe Displacement NA
Flange Pressure 1.5 F See above
Nozzle Loads Per Fabricator
U-Bolts Per Manufacturer
ASCE 7-10 – Strength 1 Pipe Straps Per Manufacturer
Anchors Per Manufacturer
ASCE 7-10 – Strength 4 Pipe Straps Per Manufacturer
Anchors Per Manufacturer
ASCE 7-10 – Strength 5 Pipe Straps Per Manufacturer
Anchors Per Manufacturer
ASCE 7-10 – Strength 6 Pipe Straps Per Manufacturer
Anchors Per Manufacturer
ASCE 7-10 – Strength 7 Pipe Straps Per Manufacturer
Anchors Per Manufacturer
Notes:
1. S = Basic Allowable Stress per Table A-1 in ASME B31.3
2. SA = Allowable Displacement Stress Range per ASME B31.3 302.3.5(d)
equation 1(b)
3. F = Flange Pressure Temperature rating per ASME B16.5
Additional model input parameters include
- The pressure case is the initial state for the temperature case
- The wind directionality factor, Kd, is conservatively taken to be 1.0 (instead of
0.95).
- The allowable displacement stress range is calculated by ASME B31.3
302.3.5(d) equation 1(b).
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Figure 7: AutoPIPE Tank Farm LN2 Fill Line Model
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Figure 8: AutoPIPE LN2 Withdrawal Line Model
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Figure 9: AutoPIPE LN2 Jacket Model
Figure 10: AutoPipe GN2 Line Model
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5.0 Piping Evaluation
Stress
Stress ratio plot for the two models are provided below in Figures 9 and 10. The
maximum stress ratio for each combination and the node where this stress occurs
is provided in the tables below. As these figures / tables demonstrate, the systems
stresses are below allowable for all load cases / combinations.
Figure 11: AutoPIPE Tank Farm LN2 Fill Line Model Stress Plot
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Figure 12: AutoPipe LN2 Jacket Model
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Figure 13: AutoPipe GN2 Line Model
LN2 Process Critical
Combination
Maximum Ratio
( Calculated Stress /
Allowable Stress)
Node
B31.3 Occasional Seismic 0.77 A19
LN2 Jacket Critical
Combination
Maximum Ratio
( Calculated Stress /
Allowable Stress)
Node
Thermal Expansion 0.79 D95
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GN2 Combination
Maximum Ratio
( Calculated Stress /
Allowable Stress)
Node
Thermal Expansion 0.88 G04
Vacuum Loads
The jacket pipe is capable for full vacuum as described below. Per 304.1.3 of
ASME B31.3, the wall thickness for external pressure shall be determined in
accordance with UG-28 through UG-30 of the ASME BPVC Section VIII,
Division 1 [12]. However, as permitted by ASME Code Case 2286-5 section 3.1,
a more modern calculation method is implemented. As seen the referenced
components list document, all sizes of vacuum jacketed pipe have external
pressure ratings above required.
Components
The pressure-temperature ratings for all components exceed the requirements of
the four pressure-temperature cases. Please reference the component list
indicated in Section 9.
6.0 Flange Evaluation
Since the flanges used in this pressure system are not standard ANSI pressure class flanges, they
are individually qualified for use by an individual examination of the pressure and external code
combination loads. Please see referenced components calculation sheet for details.
7.0 Equipment Nozzle Evaluation
The maximum loads on each equipment nozzle are provided in the table below and compared to
the allowable nozzle loads. The nozzle loads are less than the allowable nozzle loads for all load
cases / combinations, as shown in the LN2 and GN2 Components List.
Nozzle Allowable Loads
(lbf,lbf-ft)
LN2 Vaporizer
Radial: 187
Long Shear: 250
Circ Shear 250
Long Moment: 125
Circ Moment: 166
Torsion: 29
Pressure System Documentation-Calculations
Title: Nitrogen Distribution System (79720-PS-104 & 79720-PS-105) Stress Analysis
Note Number: 79720-P0002
Author(s): Connor Kaufmann Page 22 of 24
Pressure System Documentation – Nitrogen Distribution System Stress Analysis Page 22
8.0 Support Evaluation
The evaluation of the unistrut pipe straps, U-bolts and G-10CR spacers used are covered in the
referenced report listed in the associated analyses section 9. As mentioned prior, all pipe supports
are evaluated using only the LRFD ASCE 7-10 cases.
9.0 Associated Analyses / Documents
Structural analyses, pipe stress reports and pressure system documentation related to this report
are listed below.
79720-A0005 LN2 Fill Station Structural Analysis
79720-A0003 Pipe Support Structural and Anchor Analysis
79720-P0006 79720-PS-104 & 79720-PS-105 Component Lists
79720-P0005 79720-PS-104 & 79720-PS-105 Pressure System Forms
10.0 Summary / Conclusions
The pipe stresses are below allowable for all normal and occasional design conditions. The pipe
displacements are reasonable for all normal and occasional design conditions. The pipe flanges
are leak tight for all normal and occasional design conditions. The tank nozzle loads are below
allowable nozzle loads for all normal and occasional design conditions. The support loads are
below manufacturer allowable loads for all normal and occasional design conditions. Thus, the
pipe system design is acceptable.
11.0 References
[1] Process Piping, ASME B31.3-2014
[2] California Building Code, 2013
[3] Minimum Design Loads for Buildings and Other Structures. ASCE/SEI 7-10, 2010
[4] California Mechanical Code, 2013
[5] Cryogenic Plant Seismic Design Criteria, LCLSII-4.8-EN-0227-R2
[6] Final Report Geotechnical Investigation LCLS II Cryogenic Building and Infrastructure
SLAC National Accelerator Laboratory, Rutherford+Chekene #2014-106G
[7] LN2 Drawings
[8] Structural Calculations for LN2 Dewars TBD
[9] Mechanics of Materials, Beer, Johnston Jr and DeWolf – 3rd
Ed
[10] http://engineersedge.com/beam_bending/beam_bending8.htm
[11] Pipe Flanges and Flanged Fittings, ASME B16.5-2013
[12] Rules for Construction of Pressure Vessels, ASME BPVC Section VIII, Division 1-2015
Pressure System Documentation-Calculations
Title: Nitrogen Distribution System (79720-PS-104 & 79720-PS-105) Stress Analysis
Note Number: 79720-P0002
Author(s): Connor Kaufmann Page 23 of 24
Pressure System Documentation – Nitrogen Distribution System Stress Analysis Page 23
[13] Materials, ASME BPVC Section IID-2015
[14] http://www.engineeringtoolbox.com/stainless-steel-pipes-bursting-pressures-d_463.html
[15] Welded Steel Pipe Design Manual, American Iron and Steel Institute- 2007 Edition, p. 17
Pressure System Documentation-Calculations
Title: Nitrogen Distribution System (79720-PS-104 & 79720-PS-105) Stress Analysis
Note Number: 79720-P0002
Author(s): Connor Kaufmann Page 24 of 24
Pressure System Documentation – Nitrogen Distribution System Stress Analysis Page 24
Appendix A – AutoPIPE Models / Reports
The model files listed below are on file at JLab and can be provided upon request.
FILE TYPE FILE NAME
AutoPIPE Model LN2.dat
Input Database LN2_ASD_CASES1-4.dat
Input Database LN2_ASD_CASES5-8.dat
Input Database LN2_ASD_CASES9-12.dat
Input Database LN2_ASD_CASES13-16.dat
Input Database LN2_LRFD_CASES1-4.dat
Input Database LN2_LRFD_CASES5-8.dat
Input Database LN2_LRFD_CASES9-12.dat
Input Database LN2_LRFD_CASES13-16.dat
AutoPIPE Model Jacket.dat
Input Database Jacket_ASD_CASES1-4.dat
Input Database Jacket_ASD_CASES5-8.dat
Input Database Jacket_ASD_CASES9-12.dat
Input Database Jacket_ASD_CASES13-16.dat
Input Database Jacket_LRFD_CASES1-4.dat
Input Database Jacket_LRFD_CASES5-8.dat
Input Database Jacket_LRFD_CASES9-12.dat
Input Database Jacket_LRFD_CASES13-16.dat
AutoPIPE Model GN2.dat
Input Database GN2_ASD_CASES1-4.mdb
Input Database GN2_ASD_CASES5-8.mdb
Input Database GN2_ASD_CASES9-12. mdb
Input Database GN2_ASD_CASES13-16. mdb
Input Database GN2_LRFD_CASES1-4. mdb
Input Database GN2_LRFD_CASES5-8. mdb
Input Database GN2_LRFD_CASES9-12. mdb
Input Database GN2_LRFD_CASES13-16. mdb
These files are located in the folder path indicated below.
M:\cryo\CENTRAL DOCUMENTATION AREA\NON-JLAB PROJECTS DOCUMENTATION\LCLS-
II\Pressure Systems\LN2 & GN2