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ES&H Manual

Welding & Brazing Program Supplement

 

 

1.0        Purpose

 

 

This document has been written for all groups at Jefferson Lab that perform or contract welding and brazing operations in order to develop a single welding and brazing program that meets minimum requirements derived from national consensus standards.

 

The safety of welders and brazers is covered in the body of ES&H Manual Chapter 6122 Hot Work (Welding, Cutting, Brazing, and Grinding) Safety Program whereas each weld and braze produced in accordance with these requirements will provide an adequate level of safety commensurate with Jefferson Lab policy.

 

 

2.0        Scope

 

 

This program covers all welding and brazing operations conducted by Jefferson Lab.  Welding and brazing operations specifically covered include weld/braze design and weld/braze classification; weld/braze procedure specification and qualification; weld/braze performance qualification; examination and inspection; material control and documentation. 

 

Welding or brazing produced by vendors sub-contracted by Jefferson Lab do not have to follow any additional program requirements beyond what is required in nationally recognized construction codes and any supplemental contract requirements.  Respectively for pressure vessels and pressure piping, these codes are the American Society of Mechanical Engineers (ASME)Boiler and Pressure Vessel Code and the ASME B31 Piping Codes unless an equivalency is determined by the responsible engineer (Design Authority) as given in ES&H Manual Chapter 6151 Pressure Systems.

 

2.1            Exceptions:

·       Research Pressure Vessels and Pressure Piping

For pressure vessels and pressure piping where ASME Codes cannot be directly applied because of pressure range, vessel geometry, use of special material, etc., Jefferson Lab shall implement measures to provide equivalent protection and ensure a level of safety greater than or equal to the level of protection afforded by the ASME codes.

 

·       Repairs

This program does not apply to repairs made to existing structures or pressure systems.  Repairs are not considered to be changes to the original intent of the design, a change of application or structural support.  Weld/braze repairs shall be made by applying sound engineering principles and following this program to the extent practicable.

 

·       Exception Procedure for Pressure Systems

The measures used to attain an exception include the following according to 10 CFR 851:

Design drawings, sketches, and calculations must be reviewed and approved by a qualified independent design professional or a documented peer review ensured by the Pressure Systems Committee or its representative.

Qualified personnel shall be used to perform examinations and inspections of materials, in-process fabrications, non-destructive tests, and acceptance test.

Documentation, traceability, and accountability shall be maintained for each unique pressure vessel or system, including descriptions of design, pressure conditions, testing, inspection, operation, repair, and maintenance.

 

 

3.0        Responsibilities

 

 

3.1            Division Heads

Each Division Head is responsible for ensuring that all groups within each division meet the requirements of this program.  Responsibilities include establishing and maintaining documentation, assigning supervisors responsible for the design, fabrication, testing, and examination of in-house welds and brazes.

 

3.2            Environmental, Safety, Health, and Quality (ESH&Q) Division

The ESH&Q Division is responsible for providing oversight and support to the site-wide welding program.  Responsibilities include:

·       Support, oversee and/or supervise, as needed, the code inspector.

·       Provide inspection as required by ASME codes or by engineering requirements.

·       Approve and monitor vendor sub-contracts for certifications and qualifications.

·       Ensure Jefferson Lab welder, brazer and examiner qualifications are current and appropriate.

·       Monitor current requirements and certifications necessary for examination and inspection personnel.

·       Establish and maintain a welding documentation database.

·       Provide access to the welding database, standard forms, procedures, and qualifications.

 

3.3            Supervisors

Supervisors of engineers, designers, examiners, brazers and welders must be cognizant of the Jefferson Lab welding and brazing requirements provided in this program.  In particular, the supervisor shall be knowledgeable of the criteria and requirements associated with weld classification.

 

Respective supervisors shall be responsible for ensuring the engineers, designers, examiners, brazers, and welders are qualified to perform their tasks.  They shall verify certification of examiners for specific qualified examination.

 

The supervisor of the welder/brazer shall ensure that:

·       the task hazard analysis (THA) for the welding has been done.

·       all materials are handled in accordance with this specification.

·       the inspector and/or examiner are contacted as required by this program.

·       an appropriate welding/brazing specification exists and has been assigned for the work to be done.

·       a fabrication checklist or “traveler”  has been developed that contains as a minimum the required testing and non-destructive examination (NDE) requirements given by the responsible engineer.

·       the welder/brazer has attained and maintained all applicable qualifications.

 

3.4            Responsible Engineers & Designers

Responsible engineers and designers of welded or brazed assemblies of any type must be cognizant of the Jefferson Lab welding/brazing requirements provided in this specification.  For contracted work, this person is often the Subcontracting Officer’s Technical Representative (SOTR).

 

The responsible engineer shall:

·       Assign a weld classification(s) to the drawing or specification.

·       Determine and assign the appropriate welding/brazing specification to each weld/braze as required by this program

·       Provide any required analysis.

·       Ensure all the correct applicable information (e.g. design loads not given in a specification, materials, part numbers, vendor information, testing, American National Standards Institute (ANSI) and/or American Welding Society (AWS) symbols, specifications, etc.) and instructions are called out on the drawings.

·       Ensure that the design has been appropriately reviewed.

·       Ensure that the requirements of any sub-contracted work includes adherence to nationally recognized construction codes.

 

The responsible engineer may delegate design analyses but not his/her responsibilities.

 

3.5            Welders/Brazers

Welders/brazers must be knowledgeable of their qualifications and expectations with regard to their welding activities.

 

Welders/Brazers shall perform their tasks in a safe manner consistent with ES&H Manual Chapter 6122 Hot Work (i.e.:Welding, Cutting Brazing, and Grinding) Safety Program.

                                                                                                                              

Welders/brazers shall be qualified in accordance with the applicable code prior to performing welding or brazing.

 

3.6            Inspectors and Examiners

The inspector shall be part of the ESH&Q Division, either as a direct Jefferson Lab employee or a contracted service.  For ASME code-stamped pressure vessels, this person shall be an inspector regularly employed by an ASME-accredited Authorized Inspection Agency (see BPV Code, UG-91(a)(1)).

 

Inspectors shall be responsible for ensuring the QA/QC documentation is in compliance with all requirements of the applicable code. 

 

Examiners and/or test personnel shall perform their function in concert with the inspector when required.  Each welding group may have one or more personnel trained and certified as an examiner if deemed necessary by supervision and workload.

 

Specific requirements and duties of both inspectors and examiners are maintained and available for review within the ESH&Q Division.

 

 

4.0        Procedures

 

 

4.1            Weld and Braze Design

 

4.1.1       Weld and Braze Classification

All welds and brazes shall be classified by the responsible engineer according to this specification.  The responsible engineer shall use his/her best judgment to determine whether more or stricter requirements should be applied to any given weld or braze.

 

Determination of weld classification shall depend on the component or structure being welded or brazed, design conditions and risk assessment.  The component or structure shall be categorized into one of the following: pressure vessel, pressure piping, code-exempt vessel, material handling equipment, low pressure enclosure, non-critical enclosure, vacuum vessels and piping, structural components, and non-critical components. 

 

Defining the type of component to be welded or brazed and the associated design conditions are necessary to classify the weld or braze according to the pre-mitigated risk associated with each joint.  These risks are reflected in codes that are determined in ES&H Manual Chapter 3210 Appendix T3 Risk Code Assignment.

 

Weld/braze Classifications A, B and C are based on these risk codes (RC) and are summarized in Appendix A, Minimum Welding/Brazing Classification and Requirements, Appendix B Weld and Braze Classifications Charts, and Appendix C Welding Process Flowchart.  The chart presented in Appendix A outlines the minimum requirements associated with each risk class and Charts 1 and 2 in Appendix B guide the classification determination of pressure and structural related brazes and welds.  Appendix C largely defines design and other documentation required based on decisions made by the responsible engineer or welding supervisor.

 

Jefferson Lab’s policy is to apply ASME Codes where practical to vacuum system design.  To that end, if a vacuum system can be pressurized to above 15 psi under regular or failure conditions, the vacuum system shall be categorized as a pressure vessel and/or pressure piping for the purposes of classifying welds and brazes.

 

4.1.1.1  Class A

By default, all overhead material handling equipment, high hazard pressure vessels and high hazard pressure piping shall carry the highest risk: Class “A.”  In addition, all structural welds where their failure would lead to significant injury or equipment damage shall be treated as risk Class A.  Appendix B - Chart 1 & Chart 2

 

4.1.1.2  Class B

Risk Class “B” shall apply to pressure vessels and piping systems defined in the second tier (yellow) of Appendix B - Chart 1 & Chart 2 and structural welds defined in Chart 2 based on the load weight and location.  All low pressure enclosures and medium hazard ASME piping shall be assigned this risk class.  Note that there are some vessels that have internal or external pressures greater than 15 psi and fall into this classification due to limitations on inner “diameter” or if they contain water with pressure limitations (see ASME BPV Code, ¶ U-1).

 

4.1.1.3  Class C

All non-critical welding of pressure components and structures (e.g.; sheet metal) shall be assigned risk Class “C” as a minimum.  The third tier of Appendix B - Chart 1 summarizes the criteria used to establish pressure components within this class and Chart 2 assigns this lowest risk class to the lighter loads applied at lower levels.

 

4.1.2       Responsible Designer/Engineer Qualifications

 

4.1.2.1  Classes A and B Welds and Brazes

The qualifications and experience of the responsible designer/engineer depends on the complexity and criticality of the weld/braze joint.  For the design of Class A and B welds/brazes, the responsible engineer must have applicable experience, extended knowledge of the applicable ASME code(s) for pressure systems and should have familiarity with relevant nationally recognized codes or manuals for structures.

 

The responsible designer/engineer shall also meet one of following requirements to provide the engineering design of Class A welds/brazes:

·       Completion of an engineering degree, requiring four or more years of full-time study, plus a minimum of five years experience in the design of pressure systems or structures.

·       Professional engineering registration, recognized by the Commonwealth of Virginia, and experience in the design of related piping systems or structures.

·       Completion of an engineering associates degree, requiring at least two years full-time study, plus a minimum of 10 years experience in the design of pressure systems or structures.

·       15 years of experience in the design of pressure systems or structures.

·       Approval of the engineering supervisor or person of a higher organizational level.

 

4.1.2.2  Class C Welds/Brazes

These qualifications are determined by the direct line supervisor.

 

4.1.3       Documentation

All design documentation for pressure vessels and pressure piping shall be stored in an appropriate folder within the project file in DocuShare (see ES&H Manual Chapter  6151 Appendix T1 Pressure System Project Implementation and Documentation Requirements for details).  At this time, documentation associated with non-pressure system work must either reside within Documentation Control, be controlled within the group of the responsible engineer and/or the group for which the work was performed.

 

4.1.3.1  Analyses – Class A Welds and Brazes

Class A weldments / brazements shall require a documented analysis that is checked and signed by another responsible engineer, qualified as defined above, to design these joints.  Note that a weld/braze specific analysis may not be necessary if all code requirements related to these joints are followed.

 

4.1.3.1.1                 Pressure Vessels and Piping

The design analyses of pressure vessels and pressure piping shall be in accordance with ASME Section VIII and B31 construction codes.

 

4.1.3.1.2                 Structures

The responsible engineer is urged to use standard design practices in addition to any nationally recognized code applicable to the design; e.g., AWS Structural Welding Code – Steel or AISC Manual of Steel Construction. 

 

4.1.3.2  Analyses – Class B Welds and Brazes

Class B welds/brazes shall require a documented analysis initialed by a responsible engineer/designer qualified as defined above.  Note that a weld/braze specific analysis may not be necessary if all code requirements related to these joints are followed.

 

4.1.3.2.1                 Pressure Piping

The design analyses of pressure piping shall be in accordance with B31 piping codes.

 

4.1.3.2.2                 Low Pressure and Other Enclosures

The responsible engineer is urged to use a nationally recognized code applicable to the design when relevant.

 

4.1.3.2.3                 Structures

All structural welds shall be analyzed using standard engineering methods and documented.  The responsible engineer is urged to use standard design practices and any nationally recognized construction code when applicable.

 

4.1.3.3  Analyses – Class C Welds and Brazes

No design documentation is required for Class C welds and brazes.

 

4.1.3.4  Drawings and Sketches

 

4.1.3.4.1                 Class Identification

A weld or braze designated as Class A shall be identified as such in a formal drawing having the signatures of the designer or originator, the checker, supervisor and responsible engineer.  Class B welds or brazes shall be identified in either a drawing or sketch having at least the signature of the person responsible for the design.  Class C welds and brazes do not have to be specifically identified unless they coexist on a sketch or drawing with higher class joints.

 

4.1.3.4.2                 Symbols

All brazes and welds for Classes A and B shall be represented by the symbols given in ANSI/AWS 2.4, Standard Symbols for Welding, Brazing, and Nondestructive Examination.

 

4.1.3.5  Specifications

Written specifications shall address materials, inspection and examination or other requirements.  This information shall be written on the assembly drawings or other documents referenced by the drawing in absence of formal specification(s).

 

4.1.3.6  Design Parameter Form

The responsible engineer shall complete the Design Parameter Form and Fabrication Traveler for Class A and Class B welds and brazes prior to the start of fabrication.  Information on this form includes the applicable drawing numbers, weld specifications, and any required examination and testing to be performed.

 

4.2            Procedure Specifications and Qualifications

 

4.2.1       Procedure

 

4.2.1.1  Class A Welds and Brazes

Procedure qualification requirements for Class A welds and brazes, including the preparation of Welding/Brazing Procedure Specifications (WPSs/BPSs) and Procedure Qualification Records (PQRs) must meet the rules given in Articles II and XII of the ASME BPV Code, Section IX.  Similar rules given in AWS construction codes (e.g.; AWS D1.1, AWS D1.2, AWS D1.6) may be also apply provided they are the same or stricter than the ASME requirements or where the ASME requirements are not applicable.  For pressure piping, there are some modified requirements defined in each applicable ASME B31 piping code that take precedence over Section IX, e.g.  ASME B31.3 ¶ 328.2.1.

 

4.2.1.2  Class B Welds and Brazes

These qualifications shall be similar to the requirements for Class A joints with some exempted non-Code welds or brazes that are determined by the responsible engineer or supervisor to not require a formal qualification.  Exempted welds or brazes are either used primarily to seal a joint and only contribute a negligible amount toward its required strength OR they are part of a weldment/brazement where their possible failure poses little or no risk to personnel or other equipment (RC≤2).

 

4.2.1.3  Standard Welding Procedure Specifications (SWPSs)

SWPSs are not allowed to be used at Jefferson Lab due to their many limitations that can easily be violated.

 

4.2.1.4  Prequalified Procedures

A prequalified procedure used in accordance with AWS D1.1 or AWS D1.6 may be used for structural welds.

 

4.2.2       Responsibilities

The responsible engineer shall identify and assign the proper WPS/BPS to each Class A or B weld/braze joint.  The supervisor of the line supervisor in charge of welding and brazing, ensures that appropriate procedures have been determined and qualified within the group or weld shop area.

 

4.2.3       Records

Copies of all WPSs and BPSs shall be appropriately filed in DocuShare for Lab-wide use.  Each certified PQRs shall be secured with its WPS at a central location maintained by the QA & CI Department.

 

4.2.4       Qualified Welding Procedures Usage

All welding or brazing procedures, WPSs or BPSs, qualified by Jefferson Lab may only be used by Jefferson Lab personnel.

 

4.3            Performance Qualifications

 

4.3.1       Procedure

 

4.3.1.1  Classes A and B Welds and Brazes

Welding and brazing qualifications, including the preparation of Welding/Brazing Performance Qualifications (WPQs/BPQs), for pressure piping are given in Articles III and XIII of the ASME BPV Code, Section IX.  Similar rules given in AWS construction codes (e.g.; AWS D1.1, AWS D1.2, AWS D1.6) may also apply provided they are the same or stricter than the ASME requirements or where the ASME requirements are not applicable.

 

4.3.1.2  Class C Welds and Brazes

A welder or brazer does not need to be qualified for these types of joints but must be under the direct supervision of a welder or brazer qualified by an applicable ASME or ASME equivalent code.

 

4.3.2       Responsibilities

The supervisor of the line supervisor in charge of welding and brazing ensures that procedures have been qualified and the welder/brazer has been qualified to those procedures, and each welder/brazer maintains his/her qualification within the group or weld shop area.

 

4.3.3       Records

All records of certified WPQs/BPQs and shall be accessible for review, preferably within the fabrication shop along with copies filed in DocuShare.  Sufficient records shall be kept to assess whether a welder or brazer is maintaining their qualification to a process; i.e., there has not been more than a six-month period where a person has not welded or brazed to a particular process.

 

4.4            Inspections and Examinations

 

4.4.1       Inspection

 

4.4.1.1  Definition

An inspector qualified and directed by the ESH&Q Division witnesses any part of the fabrication, examination and testing procedures including a review of both material and personnel certifications and records in order to complete an inspection report for all[1] Class A and B pressure systems and any structural welding or other pressure enclosures if specified by the responsible engineer.  This inspector may also perform additional examinations or may audit those already performed.

 

4.4.1.2  Qualifications

As a minimum, the QA/QC inspector must meet the requirements of ASME B31.3, Chapter VI, ¶ 340.4 .  The inspector requirements of UG-91 of the ASME BPV may apply for pressure vessels built for others outside of Jefferson Lab.

 

Additional requirements may apply per engineering specification and are necessary for ASME pressure vessel inspection.

 

4.4.1.3  Weld Traceability

For inspection and archival purposes, Class A welds for pressure vessels shall be traceable to the welder.  This practice is also recommended for non-pressure vessel welds of this class.  This can be accomplished using a log sheet, marking a welding/brazing assembly drawing (“weld map”), or stenciling/marking the welder/brazer name or identification number near the weld on the actual assembly.  Further details and restrictions are given in UW-37(f) of ASME Section VIII, Div.1.

 

4.4.2       Examination

 

4.4.2.1  Definition

Examination applies to quality control functions performed by personnel qualified per applicable code or specification and usually includes visual observations often accompanied by some NDE and/or pressure/leak testing.  Visual examinations or “inspections” per AWS, other than “in-process” examinations, can be performed by the welder provided he is qualified to do so.  For Class A and some Class B joints, the examiner assures from all certifications, records and other documentation that materials and components are of the specified grades, have received required heat treatment, examinations and testing[2].

 

4.4.2.2  Qualifications

Examiners shall have training and experience commensurate with the needs of the specified examinations.  Qualification records of the examiners showing dates and results shall be made available for review.

 

Specific visual examiner requirements are given in the “Quality Assurance Training and Certification for Visual Examiners Procedure” given in DocuShare.

 

4.4.3       Procedure and Documentation

 

4.4.3.1  Class A

All examinations shall be performed according to a written procedure according to the applicable ASME code for pressure vessels and piping (a visual examination procedure and checklist are provided in DocuShare), the AWS structural codes and any engineering requirements for structural welding[3].  In addition to these structural requirements, a documented 125% load test is also required for all material handling equipment.

 

4.4.3.2  Class B

4.4.3.2.1                 Pressure Enclosures

All brazes and welds for pressure piping in excess of 150 psig but having a stored energy less than 100 kJ must be examined according to the applicable ASME Code.  All non-Code pressure enclosures qualifying for Class B welds or brazes and ASME B31.3 Category D Fluid Service[4] piping must be visually examined according to ¶341.4.2[5] of the ASME B31.3 Code.  In addition, all non-Code, Class B enclosures must undergo a pressure test to 110% of the maximum pressure differential if pneumatic or 130% if hydrostatic for positive or negative pressures.  All vacuum enclosures must undergo a vacuum pressure test where the system must be evacuated to 110% of the maximum pressure differential up to one atmosphere pressure.  Leak testing of the welds and brazes should subsequently follow the evacuation after there is reasonable assurance the piping is safe to examine at close distance if this is necessary.

 

4.4.3.2.2                 Structural

Structural joints for Class B require examinations as per applicable Jefferson Lab engineering requirements.

 

4.4.3.3  Class C

Examination of these joints may be determined by the line supervisor or responsible engineer.

 

4.4.3.4  Records

Certified examinations consist of NDE[6], material handling load tests and pressure/leak tests.  Records of these exams showing dates, examiner and results shall be documented and stored for retrieval in the responsible engineer's project files and optionally at the fabrication area.  All examination records associated with pressure systems (pressure piping or pressure vessels) shall be stored within the appropriate project file within DocuShare.

 

Inspection reports for pressure system Class A and B welds/brazes must be developed to verify that all of the requirements summarized in Appendix A are met.  These reports, not required for structural welding unless required by responsible engineer or contract, shall also be stored within the appropriate project file within DocuShare.

 

4.4.4       Responsibility

The responsible engineer and/or supervisor shall assure that required examinations and inspections per code or specification are performed and documented.  This engineer shall use his or her best judgment to determine whether more or stricter requirements should be applied to any given weld or braze.

 

4.5            Material Control

 

4.5.1       Inspection

Upon receipt of materials to be used for welding, the welding supervisor or designee shall inspect the documents to ensure that all welding consumables, base metals, welding gases, and electrodes conform to specification or to drawings.  As a minimum for pressure vessels, materials to be used as part of the pressure boundary shall be inspected per code requirements by the inspector.

 

4.5.2       Filler Metal Storage

Filler metal materials shall be separated by base metal and alloy, as indicated by stamping or tags, while stored in a dedicated cabinet controlled by the welding supervisor.  These items shall also be identified by heat and lot numbers to the extent practicable.  Shield Metal Arc Welding (SMAW) electrodes should be kept dry and locked in their original packaging.  Low hydrogen electrodes purchased in hermetically sealed containers shall be stored in a locked cabinet until the container is opened and then in a locked oven held at 250 F or above until used.  Any electrodes removed from the oven for less than four hours can be returned and must remain in storage for a minimum of four hours before being used.  Any electrodes removed for a time exceeding four hours shall be properly disposed.

 

4.5.3       Control

Welding consumables shall be available only through the welding supervisor.  Any unused welding rods or electrodes shall be returned into a locked consumables container.

 

4.5.4       Material Conformance and Certifications

 

4.5.4.1  Base Metal

For base metal forms (e.g., plates, heads, castings, etc.) related to Class A joints, either a certified test report (material test report or “mill certification”) or certificate of compliance is required according to the applicable code or the engineering specification for structural joints.  These documents shall list the specification designation, the grade, type and class (if applicable) of the base metal.

 

Piping components shall be “listed” according to product form specifications or “unlisted” according to published specifications that include the information given in ASME B31.3, ¶ 323.1.2.  Material supplier invoice information can be substituted for material certifications provided both product form and material specifications are noted.

 

Class B welded materials require certifications only if they are pressure systems or they are required by engineering documents.

 

All required material documentation for pressure systems shall be placed in the appropriate project file in DocuShare.

 

4.5.4.2  Filler Metal

For all classes of welding, the filler metal must be certified either by including the AWS specification and classification on the packaging or affixing its alloy designation stamped or tagged to each rod.  Shipping containers of new material must also bear the heat and lot numbers.  Older material can be used provided it is properly identified.  All packaging shall be traceable to the original manufacturer’s records.

 

4.5.4.3  Welding Gases

Certification of welding gases shall be made available from the vendor upon request.

 

 

5.0        References

 

 

5.1            Applicable External Standards

 

These standards are applicable in entirety, or in part, according to this specification.

 

5.1.1       Pressure Vessels

 

5.1.1.1  ASME Boiler and Pressure Vessel (BPV) Code

The national consensus code used as the standard for pressure vessel design, fabrication, testing and inspection at Jefferson Lab.  The most frequently used sections of the ASME BPV Code as applied to pressure vessels at Jefferson Lab are:

·       Section II: Materials, Parts A, B, C, and D

·       Section V: Nondestructive Examination

·       Section VIII: Rules for Construction of Pressure Vessels, Divisions I & II

·       Section IX: Welding and Brazing Qualifications

 

5.1.2       Pressure Piping

5.1.2.1  ASME Code for Pressure Piping B31 

The national consensus code used as the standard for piping system design, fabrication, testing and inspection at Jefferson Lab.  Sections of B31 which apply to piping systems at Jefferson Lab include:

·       B31.1 Power Piping

·       B31.3 Process Piping

·       B31.5 Refrigeration Piping

·       B31.9 Building Services Piping

 

ASME B31.3 Process Piping shall be used as the primary standard for Jefferson Lab piping systems.  Other sections shall be applied as appropriate based on sound judgment of the responsible engineer/designer and proven practices in the respective field. 

 

ASME B31.9 Building Services Piping prescribes welding and brazing requirements of piping systems for building services including those in the building or within the property limits.  This Code Section has rules for the piping in industrial, institutional, commercial and public buildings, and multi-unit residences, which do not require the range of sizes, pressures, and temperatures covered in B31.3. 

 

5.1.2.2  ASME BPV Code (see above)

 

5.1.3       Structural

·       AWS D1.1/D1.1M, Structural Welding Code—Steel

·       AWS D1.2/D1.2M, Structural Welding Code—Aluminum

·       AWS D1.6, Structural Welding Code—Stainless Steel

·       AWS B2.1-X-XXX, Standard Welding Procedure Specifications

·       AWS D1.3, Structural Welding Code—Sheet Steel

 

5.1.4       Material Handling

·       ASME 30.20, Below the Hook Lifting Devices

·       ANSI/AWS D14.1, Specification for Welding of Industrial and Mill Cranes and other Material Handling Equipment

 

5.1.5       Low Pressure Enclosures

 

5.1.6       NDE Examiner Qualification

·       ASNT Recommended Practice No. SNT-TC-1A, Personnel Qualification and Certification in Nondestructive Testing

 

5.1.7       Design

·       ANSI/AWS A2.4, Standard Symbols for Welding, Brazing, and Nondestructive Examination

 

5.2            Applicable Internal Standards

5.2.1       Jefferson Lab ES&H Manual:

·       ES&H Manual Chapter 3210 Appendix T3 Risk Code Assignment

·       ES&H Manual Chapter 6122 Hot Work (i.e.:Welding, Cutting Brazing, and Grinding) Safety Program

·       ES&H Manual Chapter 6150 Compressed, Liquefied, and Solidified Gas Program

·       ES&H Manual Chapter 6151 Pressure Systems


 

 

Appendix A

 

MINIMUM WELDING/BRAZING CLASSIFICATION AND REQUIREMENTS

Weldment / Brazement Classification

A

B

C

Risk Code*

3 or 4

2

1

PROCEDURE QUALIFICATION

ASME or meets minimum requirements of ASME for comparable procedures

ASME or meets minimum requirements of ASME for comparable procedures (see ¶ 4.2.1.2 for exceptions)

None Required

WELDER/BRAZER QUALIFICATION

ASME or meets minimum requirements of ASME for comparable procedures

ASME or meets minimum requirements of ASME for comparable procedures

Under direct supervision of Qualified Welder or Brazer

INSPECTION & EXAMINATION

ASME for pressure vessels and pressure piping

Examination per ASME for vessels and piping and per ¶ 4.4.3.2.1 for non-ASME

Responsible Engineer or Line Supervisor

100% visual examination** for all structural and material handling equipment (MHE) plus a 125% load test for MHE.  Inspection per engineering documents.

Per engineering documents for all structural

MATERIAL REQUIREMENTS 

ASME for pressure vessels and piping

ASME for pressure vessels and piping

Responsible Engineer or Line Supervisor

Material certifications per engineering documents for non-ASME

Material certifications per engineering documents for non-ASME

ENGINEERING DOCUMENTATION

Signed drawings and analysis per applicable ASME Codes for pressure systems and nationally recognized codes for structures

 Signed drawings/sketches and analysis per applicable code 

Responsible Engineer or Line Supervisor

QA DOCUMENTATION

Inspection report verifying above requirements are met for pressure systems and only if specified for structural welding

Inspection and examination documents per engineering documentation or applicable code 

Responsible Engineer or Line Supervisor

*Risk codes according to ES&H Manual Chapter 3210 Appendix T3 Risk Code Assignment, before implementation of above requirements.

**Additional examination is recommended for structural tubular welds requiring complete joint penetration.


 

 

Appendix B - Chart 1

 

PRESSURE ENCLOSURE WELD CLASSIFICATION

D (inches)

P×V

(atm×ft3)

P (psi)

CLASS

Pressure Vessel

Pressure Vessel-Water

>  6

> 300

A

Pressure Piping

≥ 253

≥ 154

A

 

 

 

 

 

CE Vessel

  6

> 15

B

LP Vessel 

> 40

≤ 15

B

Pressure Piping, B31.3 Cat. D

 

 

≥15, ≤1505

B

Pressure Piping, Low Energy

 

< 253

≥15

B

Pressure Piping-Water

≥15, ≤ 300

B

LP Piping

> 40

<154

B

LP Vacuum Piping or Vessel

> 12

> 40

< 15

B

 

 

 

 

 

NC (CE) Vessels-Water

 

 

≤ 3002

C

NC Vessel

≤ 40

≤ 15

C

NC Piping

≤ 40

< 15

C

NC Vacuum Piping or Vessel

> 12

≤ 40

< 15

C

NC Vacuum Piping or Vessel

≤ 12

< 15

C

Where:

CE       ASME BPV Code-exempted per ¶U-1 (c)(2)

D         inner diameter, width, height, or cross section diagonal

LP       low pressure

NC       non-critical

P          maximum allowable external or internal differential pressure

V         enclosure volume

 

Notes:

  1. There are various combinations of maximum pressures and volumes that do not require inspection according to the ASME Section VIII, BPV Code even though the maximum design pressure is greater than 15 psi and having an internal dimension greater than 6 inches. 
  2. Refer to ASME Section VIII, BPV Code for limitations of design pressures and temperatures.
  3. Actually 100 kJ or less of stored energy—25 atm*cubic feet is a conservative approximation of this energy from 15 psi up to 250 psi.  The stored energy of a gas is defined as its isentropic expansion and the equation is provided at the end of the worksheet in ES&H Manual Chapter 6151 Appendix T4 Pressure Systems Pressure Testing Program.
  4. Generally true for most process piping excluding flammable, damaging and toxic fluids (see B31.3).  The minimum or maximum pressure thresholds may be different for other piping applications according to their applicable code.
  5. ASME B31.3 Category D Fluid service also includes:
    1. The fluid is nonflammable, nontoxic, and not damaging to human tissues as defined in para. 300.2 of same Code
    2. Design temperature is from -20 F to 366 F

 

 

Appendix B - Chart 2

 

STRUCTURAL AND MATERIAL HANDLING WELD CLASSIFICATION

 

Is Item/System

Used Overhead?

Weight Supported

by Item/System

CLASS

Material Handling

Yes

Any

A

 

No

≥ 100 Lbs

B

 

No

< 100 Lbs

C

 

 

 

 

Structural

Yes

≥ 100 Lbs

A

 

Yes

< 100 Lbs

B

 

No

≥ 100 Lbs

B

 

No

< 100 Lbs

C

Notes:

  1. These are general guidelines and a THA shall be performed for each case to verify the above classifications
  2. Use Appendix A to determine required level of documentation based on Class

 


 

 

Appendix C

 

WELDING PROCESS FLOWCHART

Class C Flow Diagram_14may08_jpeg

Note: “welding” can either be welding or brazing and “welder” can either be a welder or brazer.


CLASS B

class B_13jun08


CLASS A

 

Class A_15oct08

 

 

Revision Summary

 

 

Revision 1.1 – April 2011 –   Content removed from ES&H Manual.  No changes to content were made.

 

 

 

ISSUING AUTHORITY

SUPPLEMENT AUTHOR

APPROVAL DATE

EXPIRATION DATE

REV.

 

 

QA/CI Dept

Mike Martin

April 2011

April 2016

1.1

 

This document is controlled as an on line file.  It may be printed but the print copy is not a controlled document.  It is the user’s responsibility to ensure that the document is the same revision as the current on line file.  This copy was printed on 5/23/2013.



[1] There are various combinations of maximum pressures and volumes that do not require inspection according to the ASME Section VIII, BPV Code even though the maximum design pressure is greater than 15 psi and having an internal dimension greater than six inches.  For these cases, it is up to the responsible engineer to determine the inspection requirements.

[2] Note that for code-stamped pressure vessels, the ASME BPV Code identifies the non-NDE examination duties as those to be performed by the inspector.

[3] Note that 100% of structural welds require visual examination or “inspection” by qualified examiners for Class A welds.  In addition, it is recommended for complete joint penetration butt welds made from one side without backing at tubular connections, the entire length of these welds must undergo additional examination.  This can be “in-process” examination identical to that detailed in ASME B31.3 or these welds can be examined by ultrasonic or radiographic methods conforming to the AWS acceptance criteria (AWS D1.1, ¶ 6.11.1).

[4] Design gage pressure is from 15 to 150 psig, temperature is from -20 F to 366 F, the fluid handled is nonflammable, nontoxic, and not damaging to human tissues as defined in para. 300.2 of ASME B31.3.

[5] “Piping and piping elements for Category D Fluid Service as designated in the engineering design shall be visually examined to the extent necessary to satisfy the examiner that components, materials, and workmanship conform to the requirements of this Code and the engineering design.  Acceptance criteria are as stated in ¶ 341.3.2 and in Table 341.3.2, for Category D fluid service, unless otherwise specified.

[6] It is up to the responsible engineer to require that records of individual visual examinations (VT) be kept since ASME B31.3 specifically does not require these ( 3442.2) other than those for in-process examinations.  AWS structural codes generally leave record keeping to the engineer or what is written in the contract.  However, the examiner shall attest that this type of examination was performed and provide results.