Lincoln Electric D1.8 User Manual
D1.8 Seismic Supplement Welding Manual
A General Overview of AWS D1.8 Structural Welding Code - Seismic Supplement
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Structural Welding Code
Seismic Supplement
2 D1.8 Seismic Supplement Welding Manual
Table of Contents
Introduction .......................................................2
Background .......................................................4
Purpose and Use ................................................6
Specifications .................................................... 6
Overview ............................................................8
Differences from FEMA 353..............................10
Introduction
Lincoln Electric, the worldwide leader in welding
equipment and consumables, is proud to present
this manual to the American Welding Society’s
D1.8 Seismic Supplement.
Because welding is essential in the construction of
the vast majority of buildings, innovative welding
techniques are and will continue to be critical to
safer, sounder structures in seismic zones.
A User’s Guide To AWS D1.8 .............................11
Engineers .....................................................11
Structural Detailers .....................................12
Fabricators and Erectors .............................12
Inspectors ....................................................18
References ........................................................19
Lincoln Electric Products .................................20
Exposure Testing ..............................................22
Appendices .......................................................24
A: D1.8 Certifications ..................................25
B: Intermix Testing ......................................40
C: Lot Control Alternative Documentation ..42
The leader in seismic welding solutions is
Lincoln Electric.
Our leadership comes from our history; for over
100 years Lincoln Electric has been at the forefront
of welding technology. It comes from our people;
Duane Miller, Lincoln’s Manager of Engineering
Services, chaired the D1.8 committee. And it comes
from our products; we have consumables and
welding solutions designed help you meet new
and evolving requirements.
To assist structural fabricators, erectors, inspectors
and specifying engineers, Lincoln Electric has
created this D1.8 Seismic Supplement Welding
Manual as an aid to understand seismic welding
requirements and the Lincoln Electric consumables
tested to meet the AWS D1.8 requirements.
This update to Lincoln Electric’s D1.8 Seismic
Supplement Welding Manual is just one more way
Lincoln sets the standard for the welding industry.
That is why, for the most reliable welds in seismic
zones, the structural fabrication industry chooses
Lincoln.
Note: Please refer to the Safety References Section on page 18 for more information on certificates, booklets and general safety practices.
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D1.8 Seismic Supplement Welding Manual
Customer Assistance Policy
The Lincoln Electric Company sells welding consumables and related equipment. On occasion, purchasers
may ask the Company for advice or information about the use of these products. As a customer
accommodation, our employees respond without charge based on information provided and their knowledge
of Lincoln Electric products. Lincoln Electric offers no guarantee or warranty, and assumes no liability, with
respect to such information or advice; nor does it assume any responsibility for updating or correcting any
such information or advice once it is given; nor does its provision of information or advice create, expand or
alter any warranty with respect to the sale of the Company’s products. Lincoln Electric expressly disclaims
any warranty of any kind, including any warranty of fitness for any particular purpose, with respect to such
information or advice. The selection and use of products sold by Lincoln Electric is solely within the control
of, and remains the sole responsibility of, the customer.
Document Updates
The information contained in this document is believed to be accurate at the time of printing and is subject
to change as additional information and data becomes available. Examples of such modifications include,
but are not limited to, the incorporation of additional product data and alterations due to AWS D1.8 updates.
The reader is encouraged to check the Lincoln Electric website for updates (www.lincolnelectric.com). This
manual references other documents not published by Lincoln Electric. Those documents are also subject to
change, and the reader is encouraged to check the latest edition of referenced documents for any changes
that might affect the content of this manual.
3
This document is an update to Lincoln Electric’s 2008 D1.8 Seismic Supplement Welding Manual and
reflects changes made to the AWS D1.8 Structural Welding Code - Seismic Supplement in 2009.
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4 D1.8 Seismic Supplement Welding Manual
Background
In January 1994, the Northridge, California earthquake caused unexpected damage to a number of welded
steel-framed buildings in the greater Los Angeles area. The Federal Emergency Management Agency (FEMA)
funded a variety of investigations that sought to address both the immediate and long-term needs related to
solving the performance problems associated with welded steel moment-frame connections. Several
documents were published as a result of these investigations, including Recommended Specifications and
Quality Assurance Guidelines for Steel Moment-Frame Construction for Seismic Applications (FEMA 353)1.
FEMA 353 discusses what has come to be known as the “Pre-Northridge Connection” and concluded that
“…the typical moment-resisting connection detail employed in steel moment-frame construction prior to
the 1994 Northridge earthquake… had a number of features that rendered it inherently susceptible to brittle
fracture. These included the following:
The most severe stresses occurred in the connection
“Wildcat” welding position
Connection detail makes it hard to inspect
Significant flexural stresses on the beam flange at the column face
Weld access hole geometry
High restraint
Weak panel zones
The report continued on to say “…additional conditions contributed significantly to the vulnerability of
connections...” including:
Low toughness FCAW-S welding the consumables
Low redundancy
Matching beam and column strength
FEMA 353 then proposed a variety of recommendations and quality assurance guidelines that addressed
various topics, including:
Overall structural design
Connection design
Connection details
Materials, including both base metal and weld metal
Workmanship
Inspection
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D1.8 Seismic Supplement Welding Manual
The provisions within FEMA 353 were not binding but did become mandatory when incorporated into
Contract Documents.
While the FEMA recommendations were being drafted, the American Institute of Steel Construction (AISC)
and the American Welding Society (AWS) began to evaluate their specifications and codes and revise them to
incorporate the post-Northridge research on steel connections. AISC issued a variety of interim updates to the
Seismic Provisions, as well as complete new editions of the standard. Contained in these AISC documents are
a variety of welding-related provisions. The primary focus of the AISC Seismic Provisions, however, is on the
design of structures intended to resist seismically induced loads, including the design of the connections and
thus, some welding-related provisions.
During this same time period, the AWS D1 Structural Welding Committee formed a new subcommittee D1L,
charged with the responsibility of developing a new standard to address welding-related requirements for
buildings designed to resist seismically induced loads. Ultimately, this subcommittee produced and the D1
committee approved, AWS D1.8 Structural Welding Code-Seismic Supplement2.
Many of the changes made to the AISC and AWS standards were the direct result of the work sponsored by
FEMA. Some of the provisions directly reflect the recommendations of FEMA 353. In other cases, the initial
recommendations were modified by the AISC and AWS consensus committees. Finally, some FEMA 353
recommendations deemed to be unnecessary by the AISC or AWS committees were eliminated.
5
The FEMA-sponsored effort focused on moment-resisting connections, whereas the AISC and AWS
documents addressed other Seismic Force Resisting Systems (SFRS), thus justifying some additional
provisions that were not contained within FEMA 353. Therefore, these latest documents do more than
simply incorporate FEMA 353 provisions directly into AISC or AWS specifications.
AWS D1.8 was approved in 2005 and first printed and distributed in 2006. In 2009 the AWS published the
second edition of the AWS D1.8/D1.8M, Structural Welding Code - Seismic Supplement. Subsequent revisions
have also been made to this document.
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6 D1.8 Seismic Supplement Welding Manual
The Purpose and Use of This Manual
This manual has been prepared by The Lincoln Electric Company to assist our customers in complying
with the requirements of AWS D1.8. Additionally, a summary of important provisions is included to assist
engineers, steel detailers and inspectors. This manual does not address every provision of D1.8, and tends
to discuss only the general condition that will typically be encountered, versus unique situations that may
arise. Readers of this manual are encouraged to obtain and review a copy of AWS D1.8, which can be
purchased through the AWS (www.awspubs.com).
Reference to AISC specifications is also made throughout this manual. Copies of pertinent AISC documents
can be downloaded from the AISC website (www.AISC.org) for free, or can be purchased in printed form.
This manual does not in any respect act as a substitute for or in compliance with AWS D1.8 or AISC
specifications. Should any conflict exist between the content of this manual and these referenced
specifications, the documents as published by AISC or AWS should be taken as the authoritative reference.
To assist the user, applicable provisions as contained in D1.8:2009 are referenced at the end of paragraphs
describing the requirements.
Specifications
AWS D1.8 and Other Specifications
AWS D1.8 alone cannot be used to design, fabricate, erect and inspect a structure intended to
resist seismic loadings. Of necessity, D1.8 is used in conjunction with other construction documents,
specifications and codes. Importantly, D1.8 does not contain all the welding-related requirements.
The general interaction of D1.8 and welding-related provisions is outlined below.
AWS D1.8 and AISC Specifications
Three AISC specifications may apply to a project where seismic resistance is required: AISC 360
Specifications for Structural Steel Buildings3, AISC 341 Seismic Provisions for Structural Steel Buildings4,
and AISC 358 Prequalified Connections for Special and Intermediate Steel Moment Frames for Seismic
Applications5. These three documents will be referred to as AISC Specifications, AISC Seismic Provisions
and AISC Prequalified Connections, respectively, throughout the remainder of this manual.
The relationship between AWS D1.8 and the AISC Specifications is no different than that between the AISC
Specifications and AWS D1.1.
There is significant interaction between the AISC Seismic Provisions and D1.8. Typically, AISC Seismic
Provisions specify where and when certain welding related provisions apply, while AWS D1.8 will specify
how such provisions are implemented. For example, AWS D1.8 does not specify when steel backing must be
removed from a connection. However, when backing removal is required by AISC specifications, AWS D1.8
specifies how the backing is to be removed.
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D1.8 Seismic Supplement Welding Manual
The AISC’s Prequalified Connections document prescribes prequalified structural connections
(beam-to-column connections, for example, not to be confused with AWS prequalified welding procedure
specifications, or with prequalified joint details). As part of connection prequalification, welding-related
issues such as backing removal, weld tab removal, weld metal properties and inspection requirements
are prescribed.
AWS D1.8 and Other AWS Standards
AWS D1.8 supplements AWS D1.1 Structural Welding Code—Steel6. D1.8 does not replace D1.1, and except
as modified by D1.8, all of D1.1 still applies when D1.8 is specified. See D1.8, clause 1.1.
AWS D1.8 is intended to be used on steel structures, where D1.1 applies. D1.8 should not, for example,
be used to supplement AWS D1.6 Structural Welding Code—Stainless Steel7. See D1.8, clause 1.3.
AWS D1.8 references the AWS A5 Filler Metal Specifications. Of particular interest is the reference to AWS
A5.20: 20058 since this specification has incorporated a new supplemental electrode designator, the “-D”
suffix. This suffix reflects a concept contained in both FEMA 353 and D1.8, that of high-low heat input
testing, discussed later in this manual. It is expected that future editions of AWS A5.29 will include a
similar supplemental designator.
7
AWS D1.8 and Contract Documents
Contract Documents are used to specify requirements that may modify provisions contained within codes.
In the case of D1.8, Contract Documents play an especially important role, since many provisions typically
required for buildings designed to resist seismic loading are not specified in D1.8. Rather, D1.8 requires that
when such provisions are to apply, the Engineer must specify them in the Contract Documents. Thus,
Contract Documents may be used to “customize” requirements around a specific project. The implication is
that one project governed by D1.8 may have significantly different requirements from another, because the
Contract Documents for the two projects are different.
AWS D1.8 and FEMA 353
D1.8 and FEMA 353 are totally separate documents, and it would be impossible to impose both provisions to
govern a project without creating significant conflict and contradictions. However, qualifications and various
tests done to meet the criteria of FEMA 353 may be used to meet similar or identical requirements in D1.8.
Accordingly, such transfer of results is encouraged in D1.8, subject to the Engineer’s approval. For example,
the welder qualification test as prescribed in FEMA 353, Appendix B is similar to that specified in D1.8 Annex
D, and the D1.8 commentary specifically encourages the Engineer to accept previous welder qualification
testing done to FEMA 353 requirements.
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8 D1.8 Seismic Supplement Welding Manual
Overview of D1.8
Content
FEMA 353 identified a variety of factors that made the pre-Northridge connection “…inherently susceptible
to brittle fracture...” and then listed variables that can be grouped into the broad categories of overall
structural design, connection design, connection details, materials, workmanship and inspection. While most
of the design-related issues are covered in AISC standards, D1.8 addresses connection details, materials,
workmanship and inspection issues.
These topics are covered in seven clauses as follows:
Clause 1 General Requirements
Clause 2 Reference Documents
Clause 3 Definitions
Clause 4 Welded Connection Details
Clause 5 Welder Qualification
Clause 6 Fabrication
Clause 7 Inspection
Following these clauses are eight mandatory annexes as follows:
Annex A WPS Heat Input Envelope Testing of Filler Metals for Demand Critical Welds
Annex B Intermix CVN Testing of Filler Metal Combinations (where one of the filler metals is FCAW-S)
Annex D Supplemental Welder Qualification for Restricted Access Welding
Annex E Supplemental Testing for Extended Exposure Limits for FCAW Filler Metals
Annex F Supplemental Ultrasonic Technician Testing
Annex G Supplemental Magnetic Particle Testing Procedures
Annex H Flaw Sizing by Ultrasonic Testing
Annex I Guidelines for the Preparation of Technical Inquiries for the Structural Welding Committee
Finally, the document concludes with an extensive commentary that provides background material and
explains the Structural Welding Committee’s intent behind many of the provisions, as well as an index.
New Terminology
In a manner that has been coordinated with the applicable AISC committees, D1.8 utilizes some new
terminology. An understanding of these terms, officially defined in Clause 3: Terms and Definitions of D1.8,
is necessary to properly apply the code.
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D1.8 Seismic Supplement Welding Manual
The seismic load resisting system (SLRS) has been renamed as seismic force resisting system (SFRS) to be
consistent with terminology as revised in AISC seismic provisions and is “the assembly of structural elements
in the building that resists seismic loads.” These are the specific components in a building, such as columns,
beams, girders and braces, and the connections that join those components designed to resist seismic loads.
The SFRS does not typically include all the various structural elements in a building. See D1.8, clause 3.1.
Demand Critical welds are defined as “welds designated by the Engineer in Contract Documents, and
required to meet specific requirements of this code.” The most rigorous requirements of D1.8 are imposed
upon welds designated as “Demand Critical” (DC). See D1.8, clause 3.2.
The protected zone (PZ) is “that portion of a member of the SFRS… in which inelastic straining is anticipated
to occur….” Special limitations apply to attachments and fabrication practices associated with this zone.
See D1.8, clause 3.3.
It is important to note that D1.8 requires the Engineer to specify in contract documents the locations of
members that are part of the SFRS, which welds are Demand Critical, and the portion of members that
comprise the protected zone. Illustrative examples are contained in the commentary, although such
examples are not prescriptive or definitive. Contract documents should contain the specific requirements
applicable to a particular project. See D1.8, clause 1.2.1.
9
Three Kinds of Welds
When a structure is designed in accordance with the AISC Seismic Provisions, the welds on the building will
fit into three categories. The applicable code depends on the characteristics of the weld, as illustrated in the
following table:
TABLE 1: CODE COVERAGE FOR VARIOUS WELDS
Not Part of SFRS Part of SFRS
Not Demand Critical Demand Critical
Code Coverage AWS D1.1 AWS D1.8 AWS D1.8 DC
Welds that are not on the SFRS as designated by the Engineer in contract documents are governed by
D1.1, and no special requirement for seismic considerations apply. Welds on the SFRS, but not designated
Demand Critical by the Engineer in contract documents, are governed by D1.8, but the additional provisions
for Demand Critical welds do not apply. Demand Critical welds (which, by definition, must be part of the
SFRS), are subject to all the applicable requirements of D1.8, as well as those additional provisions that
apply to Demand Critical welds. See D1.8, Commentary C-1.1.
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10 D1.8 Seismic Supplement Welding Manual
Differences between FEMA 353 and AWS D1.8
As was previously mentioned, much of D1.8 was based upon recommendations contained within FEMA 353.
However, differences between the two documents exist. In many cases, FEMA 353 recommendations are
not contained in D1.8, but rather reside in the applicable AISC specification. In some situations, the AWS
consensus committee made deliberate decisions to approach the issue in a different manner.
Contained below is a partial listing of some of the significant differences:
The complicated and complex “weld categories” as contained in FEMA 353 have been replaced
with the three broader and simpler categories as outlined previously in Table 1.
Details of the WPS Heat Input Envelope Testing have been modified. In D1.8, the root pass can be
made in a single pass (versus a split pass, as required in FEMA 353), and the position of welding is
no longer an essential variable for this test. See D1.8, Annex A.
The Supplemental Welder Qualification test was expanded to include a testing procedure to address
welder qualification when steel backing is not used, including where copper or ceramic backing is
used, as well as when open root joints are used. See D1.8, Annex D.
Testing of the Supplemental Welder Qualification for Restricted Access Welding may be accomplished
by either radiographic testing (RT), ultrasonic testing (UT) or by mechanical testing (FEMA 353
permitted only mechanical testing or RT). Additionally, the typographical error as contained in FEMA
353 that called for 3/4 in. bend tests has been corrected in D1.8 to call for the intended 3/8 in. thick
bend specimens. See D1.8, Annex D.
D1.8 contains more definitive alternatives to lot tested filler metals. See D1.8, clause 6.3.8.
D1.8 specifically exempts the high/low heat envelope testing for the welding consumables when
SMAW is used with specific filler metals, and when GMAW is performed with solid electrodes.
See D1.8, clause 6.3.5.
D1.8 has extended the standard exposure period for FCAW electrodes from 24 to 72 hours.
See D1.8, clause 6.4.3.
A variety of other changes have been made, and a careful review of the two documents must be made if
the user is interested in a comprehensive comparison.
Differences between AWS D1.8/D1.8M:2005
and AWS D1.8/D1.8M: 2009
The second edition of the AWS D1.8/D1.8M, Structural Welding Code – Seismic Supplement features editorial
and technical revisions from the previous edition. These revisions are primarily refinements or clarifications
of information presented in the 2005 edition.
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D1.8 Seismic Supplement Welding Manual
Significant revisions in the second edition are listed below. For more revisions please see pages vii-viii in the
AWS D1.8/D1.8M:2009.
Figures 4.1 and 4.2 – New figures added to illustrate detail of the transition of butt joints
for unequal thicknesses.
Subclause 6.3.2 – Clarified and corrected diffusible hydrogen requirements for filler metals.
Subclause 6.3.6 – Modified to disallow exemptions from heat input envelope and classification
lot testing when lowest anticipated service temperature (LAST) is less than +50°F.
Subclause CA5.2 – Removed the provision that required two passes per layer to fill the test plate.
It is now deemed acceptable to use single passes per layer since achieving acceptable results
under such conditions is typically more difficult than when split layers are used.
Subclause C6.13 – Revised welder identifications requirements to permit methods other than the
use of stamps or marks on the piece.
A User’s Guide to AWS D1.8
11
Certain portions of D1.8 are more important to some parties than others, depending on their specific role
in the construction process. The following is a general summary of sections of particular interest to the
various participants in a construction project.
Engineers
The primary tasks of the Engineer as they relate to D1.8 are contained in Clause 1.2.1, entitled
“Engineer’s Responsibilities.” The Engineer must identify, among other items, the following:
Members that comprise the SFRS
Locations of the Protected Zones in members of the SFRS
Welds that are Demand Critical
Locations where steel backing is required to be removed
Locations where fillet welds are required when backing is permitted to remain
Locations where weld tabs are to be removed
Locations where fillet welds are required to reinforce groove weld, or to improve connection geometry
Locations of weld access holes, and their required shape
The Engineer is also required to develop a Quality Assurance Plan (QAP) for the project. AISC Seismic
Provisions Annex Q contains a recommended example of a QAP that the D1.8 commentary encourages
the Engineer to adopt without modification. See D1.8, clause 1.2.1.
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12 D1.8 Seismic Supplement Welding Manual
Structural Detailers
Table 2 provides a list of references to specific D1.8 code provisions of particular interest to the
structural detailer:
TABLE 2: SPECIFIC D1.8 CODE PROVISIONS
Structural Detail D1.8 Coverage
Access Holes 1.2.1(9), 6.9
Backing—Removal 1.2.1(5), 6.7, 6.8
Backing—Remaining in Place 1.2.1(6), 6.12
Contouring Fillet Welds 1.2.1(8), 6.8
Corner Clips 4.1
Demand Critical Welds 1.2.1(4), 3.2
End Dams 6.11
k-Area Detailing 3.6, 4.1
Protected Zone 1.2.1(3), 3.3, 6.6, 6.15
Reinforcing Fillet Welds See Contouring Fillet Welds
Seismic Force Resisting System (SFRS) 1.2.1(2), 3.1
Tabs 1.2.1(7), 6.10
Tack Welds 6.6, 6.16
Tension Transition Butt Joints 1.2.1(11)
Fabricators and Erectors
Much of D1.8 is directed to the Contractor performing the welding. The various provisions directed toward
the Contractor can be grouped into these major categories:
Welder Qualification
Welding Procedure Specifications (WPSs)
Filler Metals
Techniques
Welder Qualification
Clause 5 and Annex D of D1.8 are devoted to welder qualification. In addition to meeting the welder
qualification requirements of D1.1, welders performing work under D1.8 are required to take the
Supplemental Welder Qualification for Restricted Access Welding Test, as prescribed in Annex D, when
the production weld involves all of the following:
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D1.8 Seismic Supplement Welding Manual
a) the weld is Demand Critical; and
b) the weld joins the beam bottom flange to a column flange; and
c) the weld must be made through a weld access hole in the beam web.
As mentioned above, the qualification of welders in accordance with Annex D is only required when all three
of these preceding conditions are part of the production weld. If any one is not present (i.e. a production weld
that is not made through a weld access hole) this qualification is not required, even though such a weld may
be Demand Critical. See D1.8, clause 5.1.1
The Annex D test was designed to simulate the restricted access conditions that are typically associated
with welding a beam bottom flange to a column in a moment connection. However, unlike the production
connection, the qualification test plate is a butt joint, permitting easier inspection and testing of the
completed weld. See D1.8, Annex D Figure D.1, D.2 and D.3.
Two test configurations are described in Annex D, known as Option A and Option B. Option A is to be used
when steel backing is specified on the WPS, while Option B is used for open root joints, or joints backed with
ceramic, copper or other non-steel materials. The type of test to be taken is dependent on the type of backing
(if any) that will be used in production, and as shown on the WPS. See D1.8, clause 5.1.3 and Annex D clause
D3.2, D3.3.
13
While the test plate can be tacked together by anyone, the welder must affix the weld tabs to the test plate.
Also, the welder is required to measure the preheat and interpass temperature of the test plate assembly.
See D1.8, Annex D clause D3.1.1, D3.1.3.
As is the case for D1.1, welders taking the Annex D test must qualify by welding process. In addition, the
test plate must be welded with a deposition rate equal to or higher than that which will be used in production.
It is wise, therefore, to use a slightly higher deposition rate in the welder qualification test so that the welder
will be qualified to use all production WPSs. See D1.8, Annex D clause D3.1.2
After the test plate is complete, the various restriction plates are removed and the test plate is visually
inspected. Then, at the Contractor’s option, the test plate is non-destructively (NDT) or mechanically tested.
NDT options include ultrasonic inspection (UT) and radiographic inspection (RT). Four bend tests are used
for mechanical testing. See D1.8, Annex D clause D4.
The Annex D test is similar in design, and identical in purpose, to a similar test prescribed in FEMA 353.
Welders who have been qualified previously using “similar restricted access plate tests” before D1.8 was
issued are not required to take the Annex D test, providing all the time continuity requirements are still met.
See D1.8, Annex D clause D1.
The qualification of a welder who has taken the Annex D Supplemental Welder Qualification test is valid for
36 months, providing the D1.1 continuity requirements are also met (i.e., the process is used at least every
six months). See D1.8, clause 5.2.
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14 D1.8 Seismic Supplement Welding Manual
Welding Procedure Specifications (WPSs)
A welding procedure specification is “a document providing the required welding variables for a specific
application to assure repeatability by properly trained welders and welding operators” according to AWS A3.0
Standard Terms and Definitions. AWS D1.1 requires WPSs to be documented (see D1.1 subclause 3.1, 4.6).
Under D1.1, WPSs may be either prequalified or qualified by test, and both types of WPSs may be used under
D1.8 as well.
In addition to meeting the requirements of D1.1, D1.8 mandates additional WPS requirements. Under D1.8,
WPSs must list the filler metal manufacturer as well as the filler metal trade name (such as Lincoln Electric’s
Innershield® NR®-233) as opposed to showing only the AWS classification (in this case, E71T-8). D1.8
mandates a variety of other filler metal requirements that are addressed in the next section of this manual.
See D1.8, clause 6.1(1).
WPSs must also list one or more combinations of welding variables that produce heat inputs within the
limits of the tests performed on the specific filler metal (this will be discussed in greater detail under
“Filler Metals”). Heat input is determined from the following equation:
Heat Input (H) = (60 x E x I)
1000 S
Where: H = Heat input in KJ/in (KJ/mm)
E = Arc voltage in volts
I = Current in amps
S = Travel speed in inches per minute (mm per minute)
The values for E, I and S as shown on the WPS must result in a heat input within the high and low heat input
limits for the specific electrode being used. See D1.8, clause 6.1(2).
The welding process shown on the WPS may be SMAW, GMAW (except for short circuit transfer), FCAW
(either self-shielded or gas-shielded) or SAW. Other processes are permitted under specific conditions.
See D1.8, clause 6.2.1.
The maximum interpass temperature to be shown on the WPS shall not exceed 300°C (550°F), unless an
alternative temperature (either higher or lower) has been established by test. See D1.8, clause 6.5.
Filler Metals – General
Filler metals acceptable for use on D1.8 projects are subject to a variety of requirements beyond those
imposed by D1.1. Some requirements apply to all welds governed by D1.8 while other provisions are
mandated only for the Demand Critical (DC) welds. If the weld is not on or part of the seismic force
resisting system, only D1.1 requirements apply. See D1.8, clause 6.3.
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From a practical perspective, it is expected that most contractors doing D1.8 work will use the same filler
metals for both Demand Critical welds and other welds that are part of the seismic force resisting system.
The effort required to segregate the different filler metals for different joints, and the potential consequences
of inadvertently using the wrong filler metal to make a Demand Critical weld, suggest that it is prudent to use
the same materials (i.e., those qualified for Demand Critical welds) throughout a project.
Filler Metals – All D1.8 Welds
Certificates of conformance for Lincoln Electric’s D1.8 products can be obtained at
http://www.mylincolnelectric.com/LEExtranet/MyLincolnCerts/site/awsd.aspx. Charpy V-Notch (CVN)
properties and diffusible hydrogen levels for each product are contained in these certificates.
For all work done under D1.8, filler metals are required to meet a minimum Charpy V-Notch requirement
of 20 ft•lbf at 0°F, as measured in a standard AWS A5 filler metal classification test. Higher values for the
CVN energy (i.e., >20 ft•lbf) are acceptable, as are test results involving lower testing temperatures
(i.e., lower than 0°F). See D1.8, clause 6.3.1 and Table 6.1.
Most filler metals are required to be capable of depositing weld metal with a maximum diffusible hydrogen
content of 16 mL per 100 grams of deposited weld metal, meeting the requirement for H16. Lower diffusible
hydrogen levels are acceptable (for example, H8, H4, or H2). Exemptions from the requirement include SMAW
electrodes with low hydrogen coatings which may be accepted based on meeting AWS A5.1 or A5.5 electrode
specification for coating moisture content. Solid electrodes for GMAW and EGW are exempted from any
hydrogen measurement. See D1.8, clause 6.3.2.
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When FCAW-S filler metals are combined with filler metals deposited by other processes, the combination of
the two must be checked to ensure that the minimum required Charpy V-Notch toughness can be obtained.
Annex B of D1.8 prescribes the required tests. Such testing is not required when FCAW-S is intermixed with
other FCAW-S. Alternatives to Annex B testing are also permitted by D1.8. See D1.8, clause 6.3.4 and
Annex B. Annex B of this manual contains intermix data on Lincoln Electric products.
Filler Metals – Demand Critical Welds
In addition to meeting the requirements above, filler metals used for making Demand Critical welds are required
to meet even more stringent requirements. Included are tests to evaluate the weld metal mechanical properties at
high and low heat input levels, as well as a variety of means by which lot-to-lot consistency of filler metals is ensured.
The actual mechanical properties (tensile, elongation and CVN toughness) of deposited weld metal are
dependent on a variety of factors, including the cooling rate experienced during the welding cycle. As cooling
rates are increased, the yield and tensile strength of the weld deposit typically increases, but the elongation
usually decreases. Conversely, slower cooling rates result in lower strength deposits with greater elongation.
Charpy V-notch toughness values are typically optimal at an intermediate cooling rate, and significant
changes in cooling rate (both increases and decreases) will often result in lower CVN values.
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