Summary of ASME BPVC Section IX – Part 1

ASME Boiler and Pressure Vessel Code (BPVC), Section IX contains qualification standard for the following;

  • Welding, Brazing and Fusing procedures
  • Welders and welding operators
  • Brazers and brazing operators
  • Plastic fusing operators

Section IX is a reference document for the qualification of material joining (welding, brazing and plastic fusing) processes, used by various construction codes such as Section I, III, IV, VIII, XII, etc.

NOTE: The different material joining processes covered in Section IX are;

  • Welding
  • Brazing
  • Plastic Fusing

The ASME BPVC Section IX is divided into four parts, Namely;

  • Part QG: Contains General Requirements for all material – joining processes (viz. Welding, Brazing and Plastic Fusing)
  • Part QW: Contains requirements for Welding
  • Part QB: Contains requirements for Brazing
  • Part QF: Contains requirements for Plastic Fusing

Note: Part QG General Requirements and Part QF Plastic Fusing were added in the 2013 Edition of ASME Section IX.

Since, our focus is on welding henceforth we will discuss the two parts only, i.e. Part QG (General requirements with focus on welding) and Part QW (Requirements for welding).

Part QW is further divided into five articles, these are;

  • Article 1. Welding – General requirements for welding
  • Article 2. Procedure qualification for welding
  • Article 3. Performance qualifications for welders and welding operators
  • Article 4. Welding data
  • Article 5. Standard welding procedure specifications (SWPS)

These articles contain general references and guides that apply to welding procedure specification, Procedure qualification and welder performance qualifications such as positions, type and purpose of various mechanical tests, acceptance criteria, and the applicability of Section IX.

We will discuss part QG of ASME Section IX in this article:

Part QG gives general guidelines for the following;

QG 101: Procedure specification: For each material joining process there should be a procedure specification, these procedure specifications are termed as

  • Welding Procedure Specification – WPS (for Welding)
  • Brazing Procedure Specification – BPS (for Brazing)
  • Fusing Procedure Specification – FPS (for Fusing)

Contents of a Procedure specification: The procedure specification i.e. A Welding Procedure Specification (for Welding) contains parameters related to welding process along with the values or range (as applicable) required to produce a sound weld. These parameters have been termed as variables by ASME. Variables are of three types;

  • Essential Variables
  • Non-Essential variables
  • Supplementary Essential Variables

Essential Variables (For WPS – QG-105.1 & QW-251.2): A change in essential variable is considered to affect the mechanical properties (other than toughness) of the welded joint. Hence the WPS must be requalified, if the essential variable is changed.

Supplementary Essential Variables (QG-105.3 & QW-401.1): A change in the supplementary essential variable will affect the toughness properties of the joint, heat-affected zone, or base material. Hence supplementary essential variables become additional essential variables in situations where procedure qualification requires toughness testing. When procedure qualification does not require the addition of toughness testing, supplementary essential variables are not applicable.

Nonessential Variables (QG-105.4 & QW-251.3): Nonessential variables are those in which a change can be made without requalification of the existing WPS, since it is not considered to affect the mechanical properties of the joint. Though a change in the nonessential variable doesn’t require requalification of the WPS but still it should be properly addressed in the welding procedure specification (WPS).

QG 102: Procedure Qualification Record: A Test coupon is welded based on the variables given in the proposed welding procedure specification (PWPS), then that test coupon is send to lab for destructive test. After satisfactory report of destructive test, we say that the proposed welding procedure specification (PWPS) is qualified. This entire process of qualifying the proposed WPS is known as procedure qualification and the entire data i.e. the real time data (or variables) recorded during the welding of test coupon along with the lab report of destructive test is known as Procedure Qualification Record (PQR).

Why procedure qualification is required?

The purpose of qualifying the procedure specification is to prove that the proposed welding procedure is capable of producing weld joints having the required mechanical properties for the intended application.

Qualification of the proposed welding procedure specification (PWPS) demonstrates the mechanical properties of the welded joint, and not the skill of the welder or welding operator.

The PQR shall be produced to the Authorized Inspector whenever required. One welding procedure specification (WPS) may be supported by one or more PQR(s), and one procedure qualification record (PQR) may be used to support one or more welding procedure specification(s).

Contents of a procedure qualification record (PQR)

The procedure qualification record (PQR) shall contain

  • All the real time values (or range) of all essential variables (Mandatory) recorded during the welding of test coupon,
  • Values of all non-essential variables (as required) recorded during the welding of test coupon
  • Values of supplementary essential variables (if toughness test is required) recorded during the welding of test coupon
  • Lab test report of welded test coupon

QG 103: Performance Qualification: Since, Part QG is focused on general requirements for welding, brazing and plastic fusing. Hence, it talks about the performance qualifications for all material joining processes viz. welding, brazing and plastic fusing. But since, our area of interest is welding only hence this discussion is restricted to welding only.

Performance qualification for welders (or welding operators) is carried out for checking the capability of that person to produce a sound weld.

QG 104: Performance Qualification Record: All the real time data observed during the welding of test coupon along with the mechanical test/Non-destructive test report is documented and is known as the performance qualification record. The performance qualification record shall be produced to Authorized inspector whenever needed.

QG 105: Variables: The following variables have been explained under this topic

  • QG 105.1: Essential Variables for procedure specification
  • QG 105.2: Essential Variables for performance qualification
  • QG 105.3: Supplementary Essential Variables
  • QG 105.4: Non-Essential Variables
  • QG 105.5: Special Process Variables
  • QG 105.6: Applicability

QG 106: Organizational Responsibility: Three broad terms have been discussed under this topic.

  1. Organizational responsibility for procedure qualifications (QG 106.1)
  2. Organizational responsibility for performance qualification (QG 106.2)
  3. Simultaneous performance qualifications (QG 106.3)

The important points pertaining to organization responsibility are as follows;

QG 106.1: Organizational responsibility for procedure qualifications: The Organization shall be fully responsible for the qualification of their procedure specification. Welding of test coupon shall be done under the full supervision and control of the qualifying organization and the person involved in this qualification process shall be a direct employee of that organization or shall be from an organization hired on contract for the welding services.

The following activities can be subcontracted, provided the organization accepts the full responsibility, these are;

  • Preparation of test coupon
  • preparation of test specimens (after complete welding)
  • Mechanical test or destructive test of those specimens

Two or more companies with different names but working under the same corporate ownership can use a single Welding Procedure Specification (WPS), provided all the criteria of ASME section IX has been fulfilled.

QG 106.2: Organizational responsibility for performance qualifications: the performance qualification test shall be carried out only after the qualification of Welding procedure specification (WPS).

The person involved in welding of test coupon for the qualification of welding procedure specification (WPS) shall be qualified for welding within the ranges specified for performance qualification for that particular welding process.

The performance qualification test shall be carried out under the full supervision and control of the organization. However, following activities may be subcontracted;

  • Preparation of test coupon
  • preparation of test specimens (after complete welding)
  • Mechanical test or destructive test of those specimens

The successful qualified welders (or welding operators) shall be issued a number/letter or Symbol by the organization, for identification purpose.

QG 106.3: Simultaneous performance qualifications: Two or more different organizations can participate in association to collectively qualify one or more welders and may share the information among themselves. During simultaneous performance qualifications each participating organization shall be represented by an employee of that organization designated responsibility for that purpose.

QG 107: Ownership Transfers: When a new owner acquires an Organization, then the Welding procedure specification (WPS), procedure qualification record (PQR) and the welder’s performance record of that organization remains valid for the new owner (with some conditions). Hence separate requalification is not required.

QG 108: Qualifications Made to Previous Editions: The welding procedure specification (WPS), procedure qualification record (PQR) and welder’s performance qualifications made with respect to any previous version of ASME Section IX shall remain valid and do not require any revision except as specified by QW 420. However, qualification for a new welding procedure specification and performance qualification shall be carried out in accordance with the latest edition of ASME Section IX.

QG 109: Definitions: Several definitions related to welding have been given in part QG 109. These definitions can be found in page no. 4 through page no. 14.

(Note: Purpose of this article is to give a general guideline to the readers and it shall not be considered as a substitute of code. For full terms and conditions please read ASME Section IX, 2017 edition.)

3 thoughts on “Summary of ASME BPVC Section IX – Part 1

Leave a Reply

Your email address will not be published. Required fields are marked *

Copyright © 2019 weldingandndt.com