Power Plant Construction and QA/QC Chapter 6 – Welding, Procedure and Operator Qualification Engineering Technology Division.

Power Plant Construction and QA/QC

Chapter 6 – Welding, Procedure and Operator Qualification

Engineering Technology Engineering Technology DivisionDivision

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Overview

Chapter 6 – Welding, Procedure and Operator Qualification

• All Pressure Vessel Welding Requires Welding Procedures

• All Pressure Vessel Welding Requires Welder Qualification

• ASME Code Requires Procedure and Welder Qualification

• Authorized Inspector Must Witness Procedure and Welder Quals

• Authorized Inspector Must Witness a Sample of the Weld NDE

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Welding Processes

Chapter 6 – Welding, Procedure and Operator Qualification

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Welding Basics

Chapter 6 – Welding, Procedure and Operator Qualification

Welding is the process of joining two materials using an electric arc

Primary Welding Types

•“Stick” – SMAW – Shielded Metal Arc Welding

•“MIG” – GMAW – Gas Metal Arc Welding

•“TIG” – GTAW – Gas Tungsten Arc Welding

•“Sub Arc” – SAW – Submerged Arc Welding

Six Welding Positions – Flat, Horizontal, Vertical, Overhead, Horizontal Round and Inclined

Brazing and Soldering – Non Pressure Boundary

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Welding Positions

Chapter 6 – Welding, Procedure and Operator Qualification

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SMAW Welding Basics

Chapter 6 – Welding, Procedure and Operator Qualification

• Flux Covered Rod

• Negative Polarity

• DC Voltage

• Excellent Access

• Wide Material Use

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Chapter 6 – Welding, Procedure and Operator Qualification

GMAW Welding Basics

• Gas Cover

• Positive Polarity

• DC Voltage

• Thin Materials

• Wide Material Use

• Fast Process

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Chapter 6 – Welding, Procedure and Operator Qualification

GTAW Welding Basics

• Gas Cover

• Negative Polarity

• AC or DC Voltage

• Wide Material Use

• Manual Process

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Chapter 6 – Welding, Procedure and Operator Qualification

SAW Welding Basics

• Powder Flux

• Negative Polarity

• DC Voltage

• Thick Materials

• Fast Deposition

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Welding Procedure

Chapter 6 – Welding, Procedure and Operator Qualification

WPS – Welding Procedure Specifications

PQR – Procedure Qualification Records

WQ – Welder Qualification Records

These items are based on a joint and material design by a Welding Engineer.

NDE and bend testing (DE) is used to verify procedure compliance.

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Chapter 6 – Welding, Procedure and Operator Qualification

Welding Symbols

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Welding Symbols

Chapter 6 – Welding, Procedure and Operator Qualification

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Welding Symbols

Chapter 6 – Welding, Procedure and Operator Qualification

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DestructiveTesting

Chapter 6 – Welding, Procedure and Operator Qualification

Bend

Charpy V Notch

Tensile

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Questions?

Chapter 6 – Welding, Procedure and Operator Qualification