LANL Engineering Standards Manual PD342
Chapter 17 Pressure Safety
Section D20-B31.3-G, ASME B31.3 Process Piping Guide
Rev. 2, 3/10/09
ASME B31.3 Process Piping Guide
Revision 2
RECORDS OF REVISION
Rev
Date
0
11/5/02
1
2
6/9/04
3/10/09
Description
POC
OIC
Initial issue in Section 200 of LANL Engineering
Manual Mechanical Chapter.
Tobin Oruch,
Kurt Beckman,
FWO-SEM
FWO-SEM
Administrative changes to become ESM Mechanical
Chapter Section D20 Appendix A.
Charles DuPrè,
Gurinder Grewal,
FWO-DECS
FWO-DO
Administrative changes to become ESM Pressure
Safety Chapter 17 Section D20-B31.3-G
Charles DuPrè,
Kirk Christensen,
ES-DE
CENG-OFF
1 of 168
LANL Engineering Standards Manual PD342
Chapter 17 Pressure Safety
Section D20-B31.3-G, ASME B31.3 Process Piping Guide
Rev. 2, 3/10/09
TABLE OF CONTENTS
PURPOSE .................................................................................................................................................................... 3
B31.3 INTRODUCTION............................................................................................................................................. 3
I - SCOPE AND DEFINITIONS ................................................................................................................................ 4
II - DESIGN ................................................................................................................................................................. 5
III - MATERIALS ..................................................................................................................................................... 15
IV -STANDARDS FOR PIPING COMPONENTS ................................................................................................ 15
V - FABRICATION, ASSEMBLY AND ERECTION ........................................................................................... 16
VI - INSPECTION, EXAMINATION AND TESTING ......................................................................................... 20
APPENDIX A – PIPING SPECIFICATIONS ........................................................................................................ 25
APPENDIX B – FLUID SERVICE SHEETS ......................................................................................................... 78
APPENDIX C – MATERIALS SELECTION ........................................................................................................ 98
APPENDIX D – VALVE SELECTION GUIDE................................................................................................... 103
APPENDIX E – FLANGED CONNECTIONS ..................................................................................................... 116
APPENDIX F – ALIGNMENT FIT-UP TOLERANCES.................................................................................... 123
APPENDIX G – COMPONENT IDENTIFICATION ......................................................................................... 128
APPENDIX H – LEAK/PRESSURE TESTING ................................................................................................... 136
APPENDIX I – STRESS ANALYSIS .................................................................................................................... 142
APPENDIX J – FILLET WELD SIZES................................................................................................................ 148
APPENDIX K – CLEANING CARBON AND STAINLESS STEEL PIPE....................................................... 153
APPENDIX L – BURIED PROCESS PIPE .......................................................................................................... 159
APPENDIX M – MITERED JOINTS ................................................................................................................... 160
APPENDIX N – BRANCH CONNECTIONS ....................................................................................................... 162
APPENDIX O - SAFETY CLASS PIPING SYSTEMS ....................................................................................... 164
APPENDIX P – REPAIRS, MODIFICATIONS AND MAINTENANCE ......................................................... 165
APPENDIX Q - APPLICATION OF ASME B31.3 TO RADIOACTIVE FLUIDS .......................................... 167
APPENDIX R – DEFINITION OF ACRONYMS ................................................................................................ 168
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LANL Engineering Standards Manual PD342
Chapter 17 Pressure Safety
Section D20-B31.3-G, ASME B31.3 Process Piping Guide
Rev. 2, 3/10/09
PURPOSE
This Guide provides information for the proper application of the ASME B31.3 Code "Process Piping,” It
was last updated for the 2002 edition. ASME B31.3 applies to process piping and tubing systems at Los
Alamos National Laboratory (LANL). This Guide also contains ASME B31.1 and AWWA compliant Piping
Specifications. Guide users are responsible for compliance with all aspects of the applicable Code. This
Guide addresses only B31.3, however this guidance is typical of the requirements of other piping Codes.
The information contained in this Guide provides clarification to the Code text, additional information not
contained in ASME B31.3, and design input specific to LANL. This Guide is not to be used as a standalone document. This Guide is formatted to be used in conjunction with ASME B31.3, by following the
same section numbering as B31.3 Code. Appendix references herein are to this Guide, not B31.3 or the
ESM, unless otherwise noted.
A user who desires clarifications on the application of piping related Codes and Standards should contact
the LANL Engineering Standards Pressure Safety Point-of-Contact.
B31.3 INTRODUCTION
The Introduction to ASME B31.3 states "It is the owner's [Design Authority] responsibility to determine
which Code Section is most applicable to the piping installation.”
The other ASME B31 Code Sections and other common National Consensus Codes are listed in Table 1.
Building and plumbing Codes as required by state and local jurisdictional requirements apply to potable
water, and for sewer and drain systems that do not have a process function.
Table 1- National Consensus Codes and Standards for Piping
Organization
ASME
ASME
ASME
ASME
ASME
ASME
ANSI/AGA
AWWA
AWWA
AWWA
AWWA
AWWA
AWWA
AWWA
AWWA
AWWA
NFPA
ID
B31.1
B31.4
B31.5
B31.8
B31.9
B31.11
Z223.1
C 100
C 200
C 300
C 400
C 500
C 600
C 900
M9
M11
Multiple
Title
Power Piping
Liquid Petroleum Transportation Piping Systems
Refrigeration Piping
Gas Transmission and Distribution Piping Systems
Building Services Piping
Slurry Transportation Piping Systems
National Fuel Gas Code (same as NFPA 54)
Cast-Iron Pipe, Fittings
Steel Pipe
Concrete Pipe
Asbestos Cement Pipe
Valves and Hydrants
Pipe Laying
PVC Pressure Pipe
Concrete Pressure Pipe
Steel Pipe-Guide for Design and Installation
Fire Protection Systems
Guidance supplementing the Code is necessary because the Code provides no explicit rules for
functional design, material compatibility with fluid and environment (erosion/corrosion protection, radiation
effects, etc.), layout, serviceability, steam tracing, grounding, valve and component selections, design of
pipe supports, material traceability, gasket selection, as-built tolerances, insulation, cleaning for special
process, etc. Also, for certain services some options available through B31.3 must be excluded, made
more stringent or supplemented by the designer.
Warning: The original and continued safe operation of a piping system depends on the competent
application of codes and standards.
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Chapter 17 Pressure Safety
Section D20-B31.3-G, ASME B31.3 Process Piping Guide
Rev. 2, 3/10/09
The Owner and Designer are responsible for compliance with the personnel and process qualification
requirements of the codes and standards.
In particular, the application of ASME B31.3 requires compliance with the Inspector qualification
requirements of ASME B31.3 Section VI for all fluid services (safety or non-safety related).
I - SCOPE AND DEFINITIONS
300(b) -
Responsibilities
The following responsibilities are applicable at LANL:
1)
Owner - The Owner is the Design Authority. See Acronyms and Definitions
sections in ESM Chapter 1 Section Z10 and Chapter 17, Pressure Safety.
2)
Designer - The Designer is the Design Agency.
3)
One of the signoffs on a piping work package must reflect an "Owner's
Inspector" review. This means:
The person signing must have the minimum experience of 340.4(b), and
The person signing must have verified, to the extent necessary, that code and
engineering design requirements for examination and testing are met (341.4.1).
300(c) -
300.1.1 -
300.1.3 -
300.2 -
Intent of the Code
1)
The code addresses the structural integrity of the piping system. The designer is
responsible for all other aspects of the design including the functional design of the
system.
2)
Recommendations for applying ASME B31.3 Code to repairs, modifications, and
maintenance are provided in Appendix P.
3)
Appendix B provides Fluid Service Sheets to assist in selection of materials for
compatibility with common fluid services. Historical TA-55 Specification 4401-J-1
contains material recommendations for that facility.
Content and Coverage
1)
ASME B31.3 may be applied to Radioactive Fluid Services. See Appendix Q.
2)
Transfer lines between facilities (such as waste or steam transfer lines) that
support processing functions may be designed and constructed to ASME B31.3.
Exclusions
1)
Note that paragraph 300.1.3 (a) does not exclude vacuum systems.
2)
Radioactive fluids should not be excluded from ASME B31.3 Scope.
Appendix Q.
3)
For Fire Protection, refer to the NFPA Codes and ESM Chapter 2 and associated
specifications in the LCSM.
See
Definitions
1)
Category M Fluid Service is recommended for safety class piping systems. See
Appendix O.
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LANL Engineering Standards Manual PD342
Chapter 17 Pressure Safety
Section D20-B31.3-G, ASME B31.3 Process Piping Guide
Rev. 2, 3/10/09
2)
Radioactive fluids should not be classified as Category D Fluid Service.
Appendix Q.
See
3)
The Owner’s Inspector is responsible for verifying the piping installation to the
extent necessary to be satisfied that it conforms to all applicable examination
requirements of the Code and of the Engineering Design. LANL Owner’s
Inspector(s) are designated by the Site Chief Engineer.
4)
Normal fluid service Piping Specifications (Appendix A) may be used in Category
D fluid service.
5)
Examiner - The person(s) certified by the employer as qualified to perform the
quality control functions specified in ASME B31.3. The LANL Construction
Engineering Group designates LANL Examiner(s).
II - DESIGN
301.1 -
General
Of all the design considerations listed in 301, only pressure rating is covered in the Piping
Specifications in Appendix A. The Piping Specifications provide materials, fittings, and
fasteners, which meet the pressure design requirements of B31.3. The designer must
address all design conditions.
301.2.2 -
Required Pressure Containment or Relief
Piping systems are designed to either safely contain or relieve the maximum pressure
that can be imposed. Plant fires can present a safety concern for certain piping systems.
The installation of pressure relief devices should be considered for liquid systems greater
than 6” ID that can have isolated fluid.
Helpful information is available in ESM Chapter 17.
301.5.1 -
Impact
Piping systems must be designed to withstand anticipated fluid transients
(waterhammers, pressure surges, etc.). These are the transients expected to occur
during normal operation of the system. Piping systems cannot be designed for
unanticipated transients. These are the transients that can occur if the system is not
properly operated. Unanticipated transients must be eliminated by design (layout) and
appropriate startup and operating procedures.
301.5.2/3-
Wind and Earthquake
The applicable wind and earthquake requirements are defined LANL Engineering
Standards Manual Structural Chapter 5.
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Section D20-B31.3-G, ASME B31.3 Process Piping Guide
301.5.4 -
Rev. 2, 3/10/09
Vibration
New designs, modifications, repairs, replacements, should be visually inspected at
startup to verify that vibration is not excessive. The rules of ASME "Standards and
Guides for Operation and Maintenance of Nuclear Power Plants" OM-S/G, Part 3, can be
used for guidance. The ASME OM document provides a methodology to evaluate
vibration using high cycle fatigue analysis and can be applied to any piping system.
301.8 -
Effects of Support, Anchor, and Terminal Movements
Soil settlement can adversely affect the integrity of a piping system and the flow in a
sloped line. When proper slope is required to maintain flow in an underground piping
system, soil settlements need to be evaluated in the design of the piping system.
302.2.1 -
Listed Components Having Established Ratings
Tables 326.1, A326.1, and K326.1 provide a listing of standards and specifications that
have been accepted by the Code. Some of these standards provide established
pressure/temperature ratings for components (e.g., ASME B16.5). The components may
be used in piping systems within the specified ratings without additional analysis. If these
components are used outside established ratings additional analysis is required.
302.2.2-
Listed Components Not Having Specific Ratings
Some standards and specifications provided in Tables 326.1, A326.1, and K326.1 base
pressure/temperature ratings on equivalent schedule (wall thickness) of straight
seamless piping less mill tolerance (e.g., ASME B16.11). The ratings of these
components are addressed in the piping specifications provided in Appendix A. If these
components are used outside the limits established in the piping specification additional
analysis and documentation must be provided.
302.2.3 -
Unlisted Components
The ASME B31.3 Code defines unlisted components as components not in Tables 326.1,
A326.1, or K326.1. Unlisted components can have pressure ratings but the owner and/or
the designer has the responsibility to verify that the design, materials, fabrication,
examination, and testing of the component meet the requirements of ASME B31.3.
Unlisted components are generally categorized as one of the following:
Components built to Unlisted Published Standards,
Components built to Manufacturers Standards, or
Components built to Site Standards or Engineering Design.
Each of these categories is addressed below.
COMPONENTS BUILT TO UNLISTED PUBLISHED NATIONAL STANDARDS
Components built to other published National Standards may be used provided that the
design, material, fabrication, examination, and testing have been verified to meet the
requirements of ASME B31.3. The Code states that the pressure design must meet the
requirements of paragraph 304 of B31.3. The rules described below for components
fabricated at LANL should be followed when published National Standards are not
acceptable.
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Chapter 17 Pressure Safety
Section D20-B31.3-G, ASME B31.3 Process Piping Guide
Rev. 2, 3/10/09
COMPONENTS BUILT TO MANUFACTURERS STANDARDS
Components built to Manufacturers Standards have not been established by a consensus
body and require a more detailed review than components built to Published National
Standards. Many manufacturers build components for application in ASME B31.3 piping
systems therefore, evaluations of the design, materials, fabrication, examination, and
testing to B31.3 requirements is less difficult.
The pressure/temperature design of the component should provide the same safety
margins as the Code. When evaluating these components the manufacturers should be
contacted to determine what documentation is available for the components. Suppliers
or distributors of the component may not understand the Code and may not be helpful in
resolution of the issues associated with qualifications of the unlisted component.
Manufacturers are the best source of information. If the manufacturer’s documentation is
not acceptable, the owner and designer must perform the component qualification. The
rules described below for components fabricated at LANL should be followed when
Manufacturers Standards are not acceptable. Another alternative is to select a different
manufacturer to supply components that meet B31.3 requirements.
COMPONENTS BUILT TO SITE STANDARDS
Piping components that form part of the pressure boundary of a piping system, that are
fabricated at LANL require qualification to the requirements of the B31.3 Code. The
pressure design of these components is specified in paragraph 304.7.2 of the Code. The
Code requires that calculations be performed to support the design of these components.
These calculations must be consistent with the design criteria of the Code and must
consider all applicable ambient and dynamic loads (ref. paragraph. 301.4 through
301.11). The Code also requires that the calculations be substantiated by one of the
following methods:
Extensive successful service of the component under comparable conditions
including loading, environment and fabrication of like materials,
Experimental stress analysis to code requirements,
Proof testing to code requirements, or
Detailed stress analysis to ASME B&PV Code Section VIII, Div. 2.
EVALUATION OF COMPONENTS FOR PRESSURE/TEMPERATURE RATINGS
The preceding describes actions to meet necessary Code requirements for unlisted
components. All piping components in a B31.3 system must meet the minimum Code
requirements for design, materials, fabrication, examination, and testing. The following
guidance is provided for review of these areas when evaluating an unlisted component.
DESIGN
The rules in B31.3 address the pressure design of components in paragraph 304. The
rules and equation in paragraph 304 can be applied to simple shapes, such as cylinders
and other common piping geometry. Equations and rules for additional shapes can be
found in the ASME B&PV Code Section VIII. The design methodology in Section VIII is
acceptable for unlisted component analysis in B31.3. Additional methods used to
evaluate unlisted components include the use of equations in “Roark’s Formulas for
Stress and Strain”. The use of all these equations requires that the components be
idealized into bounding shapes for which the equation is valid. Manufacturers generally
use simple shapes in the design of components, to minimize fabrication costs.
Design qualification of unlisted components can also be accomplished by comparison to
listed components with established pressure/temperature ratings. The comparison
involves a review of the wall thicknesses and geometry to demonstrate that the unlisted
component is bounded by a component with an established pressure rating.
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Chapter 17 Pressure Safety
Section D20-B31.3-G, ASME B31.3 Process Piping Guide
Rev. 2, 3/10/09
MATERIAL
Typically, unlisted components are fabricated from B31.3 listed materials. However,
when the materials are not listed by the Code, the material must be qualified in
accordance with the requirements of the Code. Reviewing the material of an unlisted
component is done to ensure a specified minimum allowable stress at the design
temperature. The sources for allowable stress values include the ASME B31 Codes of
Pressure Piping and the ASME B&PV Code Section II. B&PV Code Cases should also be
reviewed for allowable stresses for specific materials. The material should also be
reviewed for susceptibility to degradation mechanisms associated with the service
conditions, including a review of brittle fracture.
FABRICATION
The processes used to fabricate unlisted components must also be reviewed for Code
compliance. Some fabrication processes can cause gross or local wall thinning. If wall
thinning is possible, thinning should be accounted for when the nominal thickness is
specified. Additional fabrication allowances should be added to the required thickness to
account for manufacturing processes. Examples of wall thinning include the 12½% mill
tolerance that is applied to all piping and the allowances for wall thinning due to pipe
bending and threading. If welding is used, the welders and welding procedure must be
qualified to ASME Section IX. If bolting is used, torquing procedures should be
consistent with Appendix E.
EXAMINATIONS
Unlisted components fabricated at LANL must be examined in accordance with the Code.
Components that are mass-produced to manufacturer’s standards may have statistical
quality control methods applied. When components are built to manufacturer’s standards
that require examinations, the standard should be reviewed to ensure that the extent of
required examination and acceptance criteria meet the Code requirements for the
specified fluid service category. When manufacturers do not specify examination
requirements, the design should be reviewed to ensure that adequate margin (i.e., wall
thickness) exists above the minimum design requirements to address the lack of
examination. To review this aspect, the Basic Casting Quality Factors, Table A-1A of
B31.3, the Basic Quality Factors for Longitudinal Weld Joints, Table A-1B, and the Joint
Efficiencies, UW-12 B&PV Section VIII, can be used as guidance in determining an
adequate wall thickness for castings or components joined by welding.
TESTING
The B31.3 Code requires leak testing for all components. This test does not assess the
structural integrity of the components. The Code leak test is performed at pressure levels
that do not challenge the ultimate strength required by the Code. In most cases the
component is subjected to the leak test after being installed in the field. All components
should be reviewed to insure that their pressure/temperature rating is acceptable for the
test conditions.
Some components will be qualified using a structural integrity test. The B31.3 Code
accepts proof tests in accordance with the ASME B16.9, MSS SP-97, and ASME B&PV
Section VIII Division 1, UG-101.
When components are qualified by proof test, the
factor of safety between failure and the pressure rating should be as specified in the
Code to which the component was tested. When a factor of safety is not specified,
margins against failure that ensure safety equal to or superior to the intent of the ASME
B31.3 Code must be applied.
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Chapter 17 Pressure Safety
Section D20-B31.3-G, ASME B31.3 Process Piping Guide
Rev. 2, 3/10/09
INSTRUMENTS
Instruments are not in the scope of ASME B31.3. The Code defines the boundary to
include all piping (tubing) and components used to connect instruments to other piping or
equipment, but specifically excludes instruments. Instruments are usually purchased as
pressure rated components. When evaluating instruments for use in pressure piping
systems, the requirements of DOE Order 440.1A must be considered. This order states
“When National Consensus Codes are not applicable (because of pressure range, vessel
geometry, uses of special materials, etc.), implement measures to provide equivalent
protection and ensure safety equal to or superior to the intent of the ASME Code.”
When evaluating instruments the designer should ensure that the instruments are
selected to meet the requirements of the fluid service. Specifically, the instrument’s
pressure/temperature rating must be equal to or exceed the design pressure and design
temperature of the system. The attachment of the instrument to the piping system must
meet the requirements of B31.3. When instruments are fabricated from piping
components (e.g., flanges and spool pieces), the piping components must meet the
requirements of B31.3.
OTHER LOADS
The design equations and rules in the B31.3 Code only address the pressure loading of
components. Components must be designed for all applicable loads expected during the
design life of the component. See paragraph 301 “Design Condition” of B31.3 for a listing
of loads to be considered. At LANL, ESM Structural Chapter should be used to specify
NPH loading.
302.3.5
Limits of Calculated Stresses due to Sustained Loads and Displacement Strains
Stress Analysis, for loading other than pressure, per ASME B31.1 is acceptable and
recommended. When the B31.1 Code is used for the stress analysis, Paragraph 104.8
shall be used in its entirety. Appendix I provides guidance for stress analysis of piping
systems.
302.3.5(c)
Longitudinal Stresses SL
The longitudinal stress SL due to deadweight only can be kept within approximately
2300 psi if vertical hangers are spaced as shown in Table 2 (from ASME B31.1).
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Chapter 17 Pressure Safety
Rev. 2, 3/10/09
Section D20-B31.3-G, ASME B31.3 Process Piping Guide
Table 2 - Spacing of Vertical Supports
Nominal
Pipe Size
NPS
Water
Service
ft.
Steam, Gas,
or Air Service
ft.
1
7
9
2
10
13
3
12
15
4
14
17
6
17
21
8
19
24
12
23
30
16
27
35
20
30
39
24
32
42
Notes:
302.3.6 -
1)
Maximum spacing between vertical pipe supports for horizontal straight runs of
standard and heavier pipe at maximum operating temperature of 750°F.
2)
Does not apply where span calculations are made or where there are concentrated
loads between supports, such as flanges, valves, specialties, etc.
3)
The spacing is based on a fixed beam support with a bending stress not exceeding
2300 psi and insulated pipe filled with water or the equivalent weight of steel pipe
for steam, gas, or air service. The pitch of the line is such that a sag of 0.1 in
between supports is permissible.
4)
Applied only for deadweight design. Other loading conditions must be evaluated.
Limits of Calculated Stresses due to Occasional Loads
For accident (faulted) conditions and one-time non-repeated anchor motions, the
allowable stress may be increased to:
S = min (3Sh, 2Sy)
Allowables (Sh) are from B31.1 which are lower than B31.3.
304.1.2 -
Straight Pipe under Internal Pressure
For the pipe size, schedule, material and design pressure/temperature combinations
provided in the Piping Specifications, this section is met. If the piping specifications in
Appendix A are not applied for the pressure design, additional engineering
calculations are required.
304.2-
Mitered Segments of Pipe
Additional calculations are required for mitered joints. See Appendix M for mitered joint
evaluation methodology.
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Section D20-B31.3-G, ASME B31.3 Process Piping Guide
304.3 -
Rev. 2, 3/10/09
Branch Connections
Additional calculations are required to determine necessary reinforcement.
Appendix N for branch connection evaluation methodology.
307 -
See
Valves
A selection guide for valves is provided in Appendix D. This guide provides information
to aid in selection of the proper valve for the intended fluid service.
308.4 -
Gaskets
Appendix C provides information on gasket ratings to be used in the selection of gaskets.
Appendix B provides some information on compatibility of gasket materials with common
fluids.
309 -
Bolting
Torque values for flanged joints are provided in Appendix E.
319.4 -
Flexibility Analysis
Formal flexibility analysis is not necessary if:
321 -
1)
The design temperature is at or below 150°F and the piping is laid out with
inherent flexibility
2)
The design temperature is at or below 250°F and the piping is analyzed for
flexibility using simplified methods of calculation.
Piping Support
Design of pipe supports are addressed in Standards such as Manufacturers
Standardization Society of the Valve and Fittings Industry MSS-SP-58. Allowable stress
levels for supports are provided in the AISC Manual of Steel Construction and the AISC
Standard N690. N690 is normally reserved for safety class and safety significant
systems. The ESM Structural Chapter provides more details for applications at LANL.
Guidance for the design and modeling of piping supports is provided in Appendix I.
322 -
Specific Piping Systems
In addition to the Code requirements, engineering practice has lead to rules of good
design practice to provide for safe and cost-effective piping systems. The following are
examples of such rules. These rules must be applied by competent engineers in
accordance with approved procedures.
1)
Arrangement
a)
Piping should be grouped in banks, where feasible, and allow the most efficient
support arrangement. Piping oriented in one direction should be located at the
same general elevation, where feasible.
b)
Piping arrangement should provide space for maintenance, inspection and
repair of components (including disassembly).
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c)
Piping arrangement should provide access to operating areas, corridors,
observation windows, manholes and handholes.
d)
Piping should conform to plant clearances above floor and grade. A minimum
clearance of 7'-6" is desirable.
2)
Vents and Drains
a)
Vents and drains should be ¾ " or larger and as short as practical.
b)
Drains from process lines should be piped to an appropriate collection or
disposal receptacle. Drains from steam systems should be piped to boiler
feedwater system when economically justified. Otherwise, they should be
properly flashed and piped to waste.
c)
Valves should not be installed where safety/process function of a piping system
can be impeded (e.g. tank overflow lines, relief valves, vacuum breakers, etc.).
d)
Caps are needed if the vent and drain lines require pressure testing.
e)
Caps are needed if the fluid service presents a contamination concern.
f)
Vents located outside without caps should be configured so that rainwater won’t
collect in the end of the piping.
g)
Leakage through vent and drain valves on capped lines is a safety issue. The
pressure behind the cap can be a hazard for the worker during removal. If the
cap is only needed for cleanliness a small hole can be drilled in the cap or a
cover without pressure retaining capability may be used.
3)
Steam Distribution (Traps and Strainers)
a)
Steam traps and strainers should be selected, located and sized by the
designer.
Steam trap rated capacity shall have been determined by
manufacturer using ASME Performance Test Code PTC 39.1.
b)
A trap bypass should be installed only where a process requires uninterrupted
operation and the condensate must be discharged into a closed system.
c)
When a bypass is required on a bucket-type steam trap, the bypass valve must
be placed above the trap to prevent loss of prime in the event of valve leakage.
d)
End connections of traps and strainers should be the same as joints permitted
in the design except strainer blow off connections and downstream piping may
be threaded.
4)
Buried Piping
a)
5)
See Appendix L for Guidance for the Design of Underground Process Piping
Systems.
Pipe Hangers and Supports
a)
Design and manufacture of standard pipe supporting elements (catalog items)
should be per MSS-SP-58.
b)
Design of Non-standard pipe supporting elements (beams, columns, welds,
etc.) should be in accordance with the requirements as prescribed by the
American Institute of Steel Construction standards. Unless otherwise specified,
materials should be ASTM A36.
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c)
Painting and galvanizing are acceptable measures for corrosion control of
piping supports. When galvanized supports are specified, the galvanizing
should be applied in accordance with ASTM A123 or B633-SC4, Type 1.
Coating should not be applied within (or should be removed from) one inch of
weld areas. Painted or galvanized areas that have been damaged during
installation should be recoated.
d)
Unless otherwise indicated on design drawings or specifications, mislocated,
punched or drilled holes should be restored by welding per AWS D1.1 Section
5.26.5. Mislocated holes may be left open or filled with bolting only with the
written approval of the Designer.
6)
Standard Pipe Sizes
a)
The following pipe sizes (inches) are typical at LANL.
¼
1 ½
4
12
20
½
2
6
14
24
¾
2 ½
8
16
1
3
10
18
b)
Non-typical pipe sizes NPS 3/8, 1-¼ , 3- ½ , and 5 may be used for connections
to equipment, sprinkler systems and pipe jackets.
7)
Valves
a)
8)
The designer is responsible for assuring that selected valves are adequate for
the service. The Designer may select alternate valves better suited for the
service. Guidance for valve selection is provided in Appendix D.
Threaded pipe nipples should be:
a)
seamless
b)
the same material as non-threaded pipe, and
c)
of schedules as indicated in the Piping Specifications or by Design
9)
Galvanizing
a)
Galvanizing is acceptable when required for external corrosion protection.
b)
Galvanizing of pipe should be per ASTM A53.
c)
Galvanizing of flanges, unions, and fittings should be the hot-dip process per
ASTM A153. Weld end fittings NPS 4 and smaller may be black and painted
after welding. Flanges and Stub Ends that are hot dipped galvanized shall be
refaced to the requirements of the original Design Standard following the
galvanizing process.
d)
Galvanizing generally is a more economical weather-resistant coating than
sandblasting and painting for piping NPS 4 and smaller. When a piping system
requires many welded fittings the cost of grinding to remove the galvanizing for
weld preparation may be more costly than painting. Use of galvanizing as a
protective coating should be considered only when galvanizing is compatible
with the contents of the piping.
e)
Support components may have a zinc electroplate coating in lieu of a hot dip
galvanized coating. Electroplate zinc coatings are per ASTM B633 and should
specify Service Condition (SC) 4 as the required thickness.
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Chapter 17 Pressure Safety
Section D20-B31.3-G, ASME B31.3 Process Piping Guide
10)
a)
11)
Rev. 2, 3/10/09
Gasket and Packing
The designer is responsible for assuring that the flange and valve gaskets and
valve stem packing are adequate for the intended service. Guidance for the
selection of gaskets for Fluid Service application is provided in Appendix B.
Erosion/Corrosion, Radiation, and Thermal Aging
a)
The designer must consider the effects of erosion/corrosion, radiation, and
thermal aging during the material selection process.
b)
The designer must consider practices to minimize Chloride Stress Corrosion
Cracking (SCC) of austenitic stainless steels. See ESM Pressure Safety Pointof-Contact.
c)
When required by the design, austenitic stainless steel and other corrosion
resisting alloys should be evaluated for resistance to intergranular corrosion.
See ESM Pressure Safety Point-of-Contact.
12)
Piping material limitations in radiological controlled areas:
a)
Teflon thread lubricant (tape or dispersion) should be evaluated for suitability by
the designer (see App C).
b)
Plastic piping materials such as gaskets, packing, valve cavity liners,
diaphragms, etc., should be evaluated for their suitability for use by the
designer and substitutions appropriately specified in project drawings or
specifications.
c)
Piping joints that use degradable materials, such as gaskets, thread
compounds, O-rings, etc., should be evaluated for suitability for use by the
designer and substitutions appropriately specified in project drawings or
specifications.
13)
a)
Aluminum Piping
When aluminum piping is joined to vessels or piping systems constructed of
other metals, and the fluid handled is an electrolyte, there is a tendency for
aluminum at the joint to corrode. This is a problem where the other metals are
copper or carbon steel. This can be prevented by eliminating the metallic
electrical path through the joint by one of the following methods:
i)
Install a plastic flanged spool piece in the line. Check the adequacy of the
plastic spool for pressure, temperature and chemical compatibility with the
electrolyte. This method is preferred and has the advantage that sludge
inside the line will not bridge the gap from metal to metal.
ii)
Install spool pieces of heavier wall aluminum pipe (for increased corrosion
allowance). This method is especially suitable where the pipe is
dismantled frequently for other reasons.
iii)
Install insulating flange kits (insulating gaskets, bolt sleeves and bolt head
washers).
The insulating material must be checked for chemical
compatibility with the electrolyte.
b)
Aluminum pipe should be insulated from carbon steel pipe supporting
components. Examples of insulation are 15-pound asphalt-impregnated felt,
plastic coated pipe supports, or galvanized pipe supports.
c)
Aluminum flanges are not recommended. When used they should conform to
the Requirements of ASME B31.3 Appendix L and be flat faced.
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LANL Engineering Standards Manual PD342
Chapter 17 Pressure Safety
Section D20-B31.3-G, ASME B31.3 Process Piping Guide
Rev. 2, 3/10/09
d)
Threaded connections in aluminum piping should be avoided. Where fit-up to
threaded equipment is required use minimum length schedule 80 pipe with one
end threaded.
e)
Thread pipe with clean, sharp dies reserved for use on aluminum only. Use
cutting oil suitable for aluminum.
f)
Aluminum piping should be handled carefully to avoid embedding iron and
copper particles, which could cause pitting corrosion when in contact with an
electrolyte.
14)
a)
Pump Piping
For horizontal pumps with suction lift, when suction line is larger than inlet
nozzle. The following guidance applies:
i)
A reducer should not reduce by more than one pipe size.
ii)
For greater reduction, use a fabricated reducer with 100 maximum
included angle and qualify the reducer as an unlisted component.
iii)
When reducers are installed in suction lines use an eccentric reducer with
the flat side on the top.
b)
Elbows should not be installed directly on a pump’s suction unless the elbow is
equipped with straightening vanes.
c)
The designer should comply with the maximum allowable pump nozzle loads
where specified by the pump manufacturer.
15)
a)
Back Siphon/Backflow
Physical connections made between domestic water system and any industrial
piping system, vessel, or other equipment should be designed and installed to
prevent backflow and back siphonage. See ESM Chapter 6 Section D20,
Cross Connection Control subsection.
III - MATERIALS
See Appendix C for general guidance for materials selection.
See Appendix O for additional material requirements for Safety Class Piping Systems.
Fluid Service Sheets are provided in Appendix B to provide guidance on the selection of material for
compatibility with the specified fluid service.
IV -STANDARDS FOR PIPING COMPONENTS
326 -
Dimensions and Ratings of Components
ASME B31.3 Table 326.1 (also A326.1 and K326.1) identifies component standards that
are “listed.” Unlisted components (components made to standards or specifications not
identified in Table 326.1) must be qualified per ASME B31.3 paragraphs 302.2.3 and
304. Proof of qualification is the responsibility of the Owner (LANL Design Authority) or
Designer (See Paragraph 302.2 of this Guide).
A component to be used in a Code application must be listed in the Code and marked to
Code requirements. Marking requirements for common components are provided in
Appendix G.
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Chapter 17 Pressure Safety
Section D20-B31.3-G, ASME B31.3 Process Piping Guide
Rev. 2, 3/10/09
V - FABRICATION, ASSEMBLY AND ERECTION
328 -
Welding
Welding requirements of B31.3 are met by following the requirements identified in the
LANL Welding Manuals (Future).
328.5.2 -
Fillet Weld
The minimum fillet weld sizes required by B31.1 and B31.3 for slip-on flange and socket
weld connections are listed in Appendix J.
332 -
Bending
1)
The following guidance is provided for bending:
a)
Hot bending of piping should be performed in accordance with written
procedures. Hot bending of austenitic stainless steels should be followed by a
full solution anneal in accordance with written procedures.
b)
No bending should be performed at metal temperatures less than 40°F.
c)
Cold bending may be performed using hydraulic or mechanical bending
machines. Bending machines should be qualified by test for pipe minimum wall
and ovality.
d)
Mandrel and die used in bending stainless steel piping should be free of zinc.
e)
Pipe longitudinal welds should not be located within 30 degrees of the plane of
bend measured axially from the pipe centerline.
f)
Necking as determined by reduction of the outside circumference should not
exceed 4%.
g)
Creased or corrugated bends are not permitted.
h)
After bending, the finished surface should be free of cracks and substantially
free from buckling, by visual inspection. Depth of wrinkles on the inside of the
bend as determined from crest to trough should not exceed 1.5% of the
nominal pipe size.
i)
Flattening or ovality of a bend, the difference between maximum and minimum
diameters at any cross section, should not exceed 8% of nominal outside
diameter for internal pressure and 3% for external pressure.
j)
Wall thinning in piping shall not exceed:
k)
i)
10% - Bend radius of 5 pipe diameters and larger
ii)
21% - Bend radius of 3 pipe diameters.
Wall thinning in tubing shall not exceed:
i)
12% - Bend radius of 5 pipe diameters
ii)
22% - Bend radius of 3 pipe diameters
iii)
37% - Bend radius of 1.5 pipe diameters
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LANL Engineering Standards Manual PD342
Chapter 17 Pressure Safety
Rev. 2, 3/10/09
Section D20-B31.3-G, ASME B31.3 Process Piping Guide
2)
335 -
Tube bending differs from pipe bending in that it is usually performed in the field
with a manually operated bender. The following guidance is provided to ensure
good results on each bend.
a)
Measure and mark exactly, then insert tube in bender.
b)
Always attempt to bend in the same direction.
compensate for tubing stretch or pickup.
c)
Clamp tubing securely in bender.
d)
Check to make certain that the length mark is tangent to the desired angle on
the radius block or in line with the desired degree on the link member.
e)
Bend accurately to the desired angle plus springback allowance.
f)
Remove tube and check bend angle and measurement length.
If backbending, be sure to
Assembly and Erection
1)
For tolerances on fabrication, refer to the Pipe Fabrication Institute Standard ES-3,
"Fabrication Tolerances".
2)
Typical tolerances for erection (field installation) are the larger of 6" or D/2 for
safety related piping and 12" or D for non-safety related piping, while maintaining
code, design and vendor alignment and slope requirements. Tolerance must not
affect the sequential location of components, and fittings.
3)
The following general requirements apply to buried pipe:
a)
For installation of buried process piping refer to Appendix L.
b)
Permits from the New Mexico Environment Department and environmental
impact reports for the DOE may be required.
c)
Bedding material should be granular, well graded and capable of being
compacted flat
d)
Backfill or fill material should contain no rocks and stones larger than 3 inch in
the greatest dimension and should be free of frozen lumps, vegetable matter,
trash, chunks or highly plastic clay or other unsatisfactory matter.
e)
As an option, Controlled Low Strength Material (CLSM or “flowable fill”) may be
substituted for bedding material, embedment material or backfill material.
f)
Prior to excavation, the existing underground structures and/or utilities should
be located.
g)
Where the trench bottom is unstable or contains unsuitable material, this
material should be excavated to a minimum depth of 6". The excavated
material should then be replaced with suitable material, or CLSM.
h)
Compaction testing of bedding (excluding CLSM materials) should be done at
frequencies specified by design in any location specified by the cognizant
inspection authority. Bedding sections failing to meet these specifications shall
be removed and replaced, or reworked.
i)
The minimum depth of cover shall be 30” (top of pipe to finished grade).
j)
The minimum slope or grade indicated on design documents shall be
maintained regardless of other installation tolerance.
k)
The use of vertical installation tolerance shall not increase unvented high points
unless these are explicitly approved.
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Chapter 17 Pressure Safety
Section D20-B31.3-G, ASME B31.3 Process Piping Guide
l)
335.1.1(a) -
Rev. 2, 3/10/09
Upon completion of installation, record the as-installed piping geometry to
within the tolerance as shown below:
i)
Vertical plane = + 1"
ii)
Horizontal plane = + 3"
Alignment (Piping Distortions)
Allowable misalignment and fit-up tolerances are provided in Appendix F.
335.1.1(c) -
Alignment (Flanged Joints)
The allowable flange gaps per B31.3 are provided in Appendix E. Allowable flange
rotations above those provided in the Code are provided in Appendix F.
335.2 -
Flanged Joints
Refer to Appendix E for guidance on the proper installation of flanged connections.
335.3 -
Threaded Joints
1)
Threaded components and threaded ends are examined before assembly for
cleanliness and continuity of threads and are in conformance with applicable
standards.
2)
Compound or lubricant used on threads is suitable for the service conditions and
shall not react unfavorably with either the service fluid or the piping material.
3)
Threaded joints to be seal welded are made up without thread compound or
lubricants.
4)
When design requires threaded piping to be seal welded, seal welds shall cover all
exposed threads.
5)
Installation of threaded joints involves the cutting of threads and assembly of the
joint. Cutting threads with a hand threader involves the following steps. Threads
may also be cut with a power threader.
a)
Select the proper size of die.
b)
Clean surface of pipe. Be sure the end is square and free of burrs. Tapering
the end of pipe is helpful starting the dies.
c)
Mount the threader on the pipe making sure that the taper is headed in the
forward direction.
d)
Use thread cutting oil.
e)
Pressure should be applied to start dies on pipe.
f)
The thread length is correct when the outer surface of die is even with the end
of the pipe.
g)
Remove die and clean threads with brush or rag.
h)
Apply joint compound or tape that has been approved by the Facility for the
application.
i)
Hand tighten fitting, then tighten to required degree of tightness with correct
wrench.
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Chapter 17 Pressure Safety
Section D20-B31.3-G, ASME B31.3 Process Piping Guide
335.6. -(a)
Rev. 2, 3/10/09
Expanded Joints and Special Joints
Special precautions should be taken for any piping system containing an expansion joint
assembly.
335.6. - (b)
1)
The manufacturer's and/or designer's special installation instructions shall be
followed.
2)
Expansion joint assemblies should be carefully unpacked and erected to avoid
mechanical damage to the assemblies while handling or rigging. Erection straps
or chains shall not be loaded against or connected to bellows elements, covers or
any assembly hardware during erection.
3)
Prior to connecting or installing an expansion joint assembly, the erector should
inspect the assembly to insure that all factory-installed shipping bars, brackets or
other locking devices are in place. No modification to or removal of these devices
shall be permitted until after the piping system closures are completed.
4)
The expansion joint assembly may be equipped with permanent tie rods or limit
rods, which are necessary for the functional operation of the joint assembly.
Where provided, these rods shall not be removed, nor their factory set lengths and
clearances modified, without approval by the designer.
5)
An expansion joint assembly shall not be exposed to hydrostatic test or pressure
flushing operations until all permanent anchors, guides and restraints are installed
on the piping system. Hydrostatic test or flushing pressure shall not be greater
than the manufacturer's recommended test pressure. All temporary shipping bars
or brackets should be removed prior to system pressurization.
Special Joint - Compression Fittings
Specialty fittings are considered as unlisted component but are acceptable for use where
identified in the attached Piping Specifications. The following guidance is essential for
the proper installation and maintenance of compression fittings. The following instructions
are applicable to Swagelok and Parker fittings.
1)
Ends must be cut square. The preferred method of cutting tubing is by hacksaw
with suitable guide for squareness. Tube cutters should not be used for stainless
steel due to work hardening.
2)
Burrs must be removed inside and outside for proper entry into fitting and to
prevent system contamination and or restricted flow.
3)
Tube ends must be clean. Remove all filings, chips, and grit before attachment of
fittings.
4)
Tube line fabrication (bend angles and measured lengths) must be accurate so
that the tube end easily enters the fitting in proper alignment. Do not force an
improperly fitted tube line into the fittings.
5)
The tube end must be bottomed against the shoulder in the fitting body. This is
necessary to prevent movement of the tube while the nut forces the ferrule to grip
the tube, and to seal through any imperfections that may exist on the outside tube
surface.
6)
Never permit the fitting body to rotate during tube end make-up. Two wrenches
must be used. Assemble port connectors to components first and hold with
wrench while making up the tube joint. All types of union bodies must be held
while each of the tube ends is made up.
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Chapter 17 Pressure Safety
Rev. 2, 3/10/09
Section D20-B31.3-G, ASME B31.3 Process Piping Guide
7)
Never attempt to make up by torque or feel. Always turn the nut the prescribed
amount (listed below) regardless of the torque required.
Sizes 1/16” - 3/16”
Sizes ¼ ”- 1”
¾ of a turn from finger tight
1 ¼ turns from finger tight
Note: Fitting end plugs require only ¼ ” turn from finger tight make up in all
sizes.
335.6. -(c)
Remaking an Existing Joint
Remaking an existing joint is as important as the initial installation. The following
instructions are provided for the remake of these joints.
1)
A disassembled joint can be remade simply by retightening the nut to the position
of the original make-up. For maximum number of remakes, mark the fitting and
nut before disassembly.
2)
Before retightening, make sure the components are clean and that the assembly
has been inserted into the fitting until the ferrule(s) seats in the fitting.
3)
Retighten the nut by hand. Rotate the nut with a wrench to the original position as
indicated by the previous marks lining up. A noticeable increase in mechanical
resistance will be felt indicating the ferrule is being re-sprung into sealing position.
Then snug the nut 1/12 turn (½ hex flat) past the original position.
4)
Check ferrule orientation when applicable.
5)
Use gap gage when applicable.
VI - INSPECTION, EXAMINATION AND TESTING
340.4-
Qualification of the Owner’s Inspectors
Qualification of individuals performing the Owner’s Inspector Function shall meet the
requirements of this paragraph. Owner’s Inspectors are designated by the Site Chief
Engineer. Refer to the IFMP Training and Qualification Program ACP-T&Q-01 (future).
341.4 -
Extent of Required Examination
"Examination" is not limited to welds. Records, materials, fabrication, erection pressure
testing, as-built, must also be examined as specified by Code. Refer to Table 3 for a list
of examination attributes and the extent of required examination.
Table 3 - EXAMINATION OF MATERIALS, FABRICATION AND INSTALLATION
Extent of Required Examination
Category D
Normal
Category M
High Pressure
Severe Cyclic
Material
Fabrication
Fabrication of
Longitudinal
Welds
Mechanical
Joints
Erection
Complete
system Meets
Design (2)
Other
Examinations
Random
Random
Random
100%
Random
Random
5%(5)
100%
100%
100%
Random
100%
100%
100%
100%
Random
Random(1)
100%
100%
100%
Random
Random
Random
Random
100%
Random
Random
Random
Random
Random
Random (3)
5% Vol. (4)
20% Vol.
100% Rad.
100% Vol.
Notes:
(1) When pneumatic testing is to be used, 100% of mechanical joints shall
be examined.
(2) Includes any additional examination or testing required by engineering.
(3) Category D Systems require welds to be random visually examined.
(4) When brazed joints are used, 5% in-process examination is performed.
(5) Socket welds require 5% visual examination of final weld.
Note: Vol = Volumetric weld examination such as a radiograph or ultrasonic.
Rad = Radiography
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LANL Engineering Standards Manual PD342
Chapter 17 Pressure Safety
Section D20-B31.3-G, ASME B31.3 Process Piping Guide
Rev. 2, 3/10/09
Guidance of specific examinations other than welds is provided below.
intended to be an all-inclusive list of items to be examined.
This is not
MATERIAL
1)
At point of installation, materials and components are sufficiently identified by
markings, tags, or documentation to assure they are in accordance with the
specified requirements and traceable to the required documentation.
FABRICATION
1)
After bending, the finished surface should be free of cracks and substantially free
from buckling, by visual inspection. Depth of wrinkles on the inside of the bend as
determined from crest to trough should not exceed 1.5% of the nominal pipe size.
2)
Thinning of wall thickness after bending and forming of pipe does not exceed the
following: 10% for bend radii of greater than or equal to 5 pipe diameters, or 21%
for bend radii of less than or equal to 3 pipe diameters.
3)
Thinning of wall thickness after bending and forming of tube does not exceed the
following: 12% for bend radii of greater than or equal to 5 pipe diameters, 22% for
bend radii of less than or equal to 3 pipe diameters, or 37% for bend radii of less
than or equal to 3 pipe diameters.
4)
Necking down after bending and forming as determined by reduction of the outside
circumference does not exceed 4%.
5)
Flattening or ovality of a bend, the difference between maximum and minimum
diameters at any cross section, does not exceed 8% of nominal outside diameter
for internal pressure and 3% for external pressure.
6)
Cold bending is done at a temperature below the transformation range.
7)
No pipe bending is performed at metal temperatures less than 400F.
8)
Hot bending is performed to a design approved procedure.
9)
Longitudinal weldments are not located within 30 degrees of the plane of bend.
10)
Welding examinations are per the LANL Welding Manuals (future).
FABRICATION OF LONGITUDINAL WELDS
1)
Perform radiography for longitudinal groove welds required to have a weld joint
factor Ei equal to or greater than 0.90.
MECHANICAL JOINTS
1)
Threads in the bolts and nuts to be free from nicks, burrs, grit, chips, and dirt and
well lubricated prior to makeup.
2)
Bolts extend completely through their nuts.
3)
Manufacturer’s and designer’s installation instructions for expansion joints has
been followed, and all factory installed shipping bars, brackets, or other locking
devices are in place and remain in place until after piping system closures are
complete.
4)
Any damage to the gasket seating surface which would prevent gasket seating has
been repaired, or the flange replaced. Refer to Appendix E.
5)
The nuts have been tightened in a staggered crisscross pattern and in increments
of not more than 1/3 the total required torque.
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Chapter 17 Pressure Safety
Section D20-B31.3-G, ASME B31.3 Process Piping Guide
Rev. 2, 3/10/09
6)
No more than one gasket is used between contact faces in assembling a flanged
joint.
7)
Galvanized flanges must be refaced with the appropriate surface finish after
galvanizing in complete.
8)
Prior to bolt up, flange faces are aligned within 1/16” in./ft. (0.5%) measured across
any diameter and flange bolt holes are aligned within 1/8” maximum offset. Refer
to Appendix F for guidance on misalignment fit-up tolerance.
9)
Sealing surfaces of the flare of flared tubing joints are examined for imperfections
before assembly.
10)
Where the manufacturer’s instructions call for a specified number of turns of the
nut, these shall be counted form the point at which the nut becomes finger tight.
11)
Threaded components are examined before assembly for cleanliness and
continuity of threads and for conformance of threads with applicable standards.
12)
Compound or lubricant used on threads (for components and bolts) is suitable for
the service conditions and shall not react unfavorably with either the service fluid
or the piping material.
13)
Threaded joints to be seal welded are made up without thread compound or
lubricant.
14)
When design requires threaded piping to be seal welded, seal welds shall cover all
exposed threads.
ERECTION
1)
Piping is not distorted to bring it into alignment for joint assembly.
2)
Wedges are not being used to laterally contain or position pipe for closure fit-ups.
3)
The amount and direction of cold spring, (defined as the intentional deformation of
piping during assembly to produce a desired initial displacement and stress) is in
accordance with the design values.
4)
Support locations, type, and restraint direction are as specified in the design
drawing.
5)
Pipe slope has been maintained in the direction specified by the slope arrow
and/or work point elevation indicated on the design drawing.
6)
Changes in piping elevation have not impacted slope requirements, high point
vents, or low point drains.
7)
Upon completion of installation the as-installed piping geometry has been recorded
on the design documents. Typical tolerances for erection (field installation) are the
larger of 6” or D/2 for safety-related piping or 12” or D/2 for non-safety related
piping, while maintaining code, design and vendor alignment and slope
requirements. Tolerance must not affect the sequential location of components
and fittings, or the centerline lengths.
8)
Valves and other components are oriented as shown in design documents or
manufacturer’s requirements.
9)
Insulation is installed as specified.
10)
There are no visible defects, missing or damaged parts in piping, components, or
piping supports.
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Chapter 17 Pressure Safety
Section D20-B31.3-G, ASME B31.3 Process Piping Guide
Rev. 2, 3/10/09
COMPLETE SYSTEM MEETS DESIGN
1)
Examination of erected piping for evidence of defects that would require repair or
replacement, and for other evident deviation from the intent of the design.
2)
Any additional requirements supplementing the Code as specified by the design.
3)
Cleanliness of piping is in accordance with the requirements of the applicable
standard or as specified by design.
OTHER
1)
Welding examination requirements are per the LANL Welding Manuals (future).
341.4.1(b)(1)- Other Examinations
In-process examination may be substituted for volumetric examination on a weld-for-weld
basis, if volumetric examination of a particular weld is prohibitive. This substitution
cannot be granted across the board for a whole job.
Requirements for examinations of repairs and alterations of in-service piping are provided
in Appendix P.
342-
Examination Personnel
Examiners shall have training and experience commensurate with the needs of the
specified examinations. The employer shall certify records of examiners employed,
showing dates and results of personnel qualifications, and shall maintain them and make
them available to the Inspector. Examinations other than welds shall be conducted per
the PS Division requirements.
345 -
Testing
Table 4 is a summary of the leak test requirements of B31.3. Refer to Appendix P for
testing requirements associated with Repairs, Alterations, and Modifications.
Guidance for performing Leak/Pressure testing is provided in Appendix H.
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Chapter 17 Pressure Safety
Rev. 2, 3/10/09
Section D20-B31.3-G, ASME B31.3 Process Piping Guide
TABLE 4 - LEAK TESTING MATRIX
For Initial Installations & Fabricated Subassemblies
Fluid
Service/
Piping
Type
Category D
Metallic
Type of Test
Hydrostatic
Pneumatic
Primary leak
test method
May be substituted
in lieu of the
hydrostatic method
when approved by
the Owner.
May be substituted
in lieu of the
hydrostatic method
when approved by
the Owner.
May be substituted
in lieu of the
hydrostatic method
when approved by
the Owner.
May be substituted
in lieu of the
hydrostatic method
when approved by
the Owner.
May be substituted
in lieu of the
hydrostatic method
when approved by
the Owner.
Requires additional
Sensitive Leak
Test.
Category D
NonMetallic
Primary leak
test method
Normal
Fluid
Service
Metallic
Primary leak
test method
Normal
Fluid
Service
NonMetallic
Category M
Metallic
Primary leak
test method
Category M
NonMetallic
Primary leak
test method
Primary leak
test method.
Requires
additional
Sensitive
Leak Test.
Combined
Hydro/Pneu.
May be substituted
in lieu of the
hydrostatic method
when approved by
the Owner.
May be substituted
in lieu of the
hydrostatic method
when approved by
the Owner.
May be substituted
in lieu of the
hydrostatic method
when approved by
the Owner.
May be substituted
in lieu of the
hydrostatic method
when approved by
the Owner.
May be substituted
in lieu of the
hydrostatic method
when approved by
the Owner.
Requires additional
Sensitive Leak
Test.
Alternative
Sensitive
Initial Service
May be
substituted for
the hydrostatic
or pneumatic
leak tests (1)
Not Applicable
Part of the
Alternative Leak
Test
May be
substituted for
the hydrostatic
or pneumatic
leak tests (1)
Not Applicable
Part of the
Alternative Leak
Test
May be used at
the Owner's
option in lieu of
the hydrostatic
leak test
May be used at
the Owner's
option in lieu of
the hydrostatic
leak test
Not Applicable
Not Applicable
Not Applicable
May be
substituted for
the hydrostatic
or pneumatic
leak tests (1)
Required to be
used in
conjunction with
hydro, pneu,
combined test
methods, or as a
part of the
Alternative Leak
Test
Not Applicable
Not Applicable
Not Applicable
May be substituted
May be substituted
Not Applicable
Not Applicable
in lieu of the
in lieu of the
hydrostatic method
hydrostatic method
when approved by
when approved by
the Owner.
the Owner.
High
Primary leak
May be substituted
May be substituted
Not Applicable
Not Applicable
Not Applicable
Pressure
test method
in lieu of the
in lieu of the
Metallic
(2)
hydrostatic method
hydrostatic method
(2)
(2)
(1)
May be substituted for the hydrostatic or pneumatic leak tests provided: a) The Owner has determined a hydrostatic test would
damage linings or internal insulation, or contaminate a process which would be hazardous, corrosive, or inoperative in the presence of
moisture, or would present the danger of brittle fracture due to low metal temperature during the test. b) The Owner has determined a
pneumatic test would present undue hazard of possible releases of energy stored in the system, or would present the danger of brittle
fracture due to low metal temperature during the test. In either case approval of the ESM Pressure Safety Point-of-Contact must be
obtained.
(2)
Additionally the piping in the installed configuration must be tested to 110% of the design pressure.
24
LANL Engineering Standards Manual PD342
Chapter 17 Pressure Safety
Section D20-B31.3-G, ASME B31.3 Process Piping Guide, App A
Rev. 2, 3/10/09
APPENDIX A – PIPING SPECIFICATIONS
The attached piping specifications provide the required data to meet the pressure design requirements of
the ASME B31.3 piping code. Additional requirements and competent engineering are required to
provide a safe and complete piping system design. Additional requirements include material selection,
functional design, system layout, component selection, support design, thermal expansion, stress
analysis, examination and testing. These specifications must be used in conjunction with ASME B31.3
and this Guide to ensure a sufficient piping system design.
WARNING
Successful application of each piping specification requires the reading and comprehension
of all applicable General Notes.
When these guides are not applied in the pressure design of a piping system additional
calculations are required.
The Piping Specifications are organized as follows:
100 Series
200 Series
300 Series
400 Series
500 Series
900 Series
Carbon Steels
Stainless Steels
High Alloy Steels