Quality of manufacture and construction - Atoms for … of manufacture and construction Every weld in a pipe or vessel could be a source of failure; ... Narrow Gap MIG Welding Hot

Copyright 2013 Hitachi GE Nuclear Energy, Ltd - All rights reserved

Quality of manufactureand construction

Kenichi YasudaSenior Engineer, Hitachi GE

INPRO Dialogue Forum

November 19-23, 2013


Evaluation parameter EP1.1.1.3: Quality of manufacture and constructionQuality of manufacture and constructionQuality of manufacture and constructionQuality of manufacture and constructionEvery weld in a pipe or vessel could be a source of failure; therefore a reduction of welds in

piping or vessels clearly results in an increase of robustness of the design of an INS. In addition,

fewer welds require less in service inspections und thus should lead to reduced doses for the

personnel. As in other areas, progress in welding engineering and fabrication of pipes exists.

Progress of welding engineering includes the application of automatic welding machines during

manufacturing, which results typically in a higher quality of welds compared

to manual welding procedures. Progress in fabrication of pipes includes the elimination of

longitudinal welds by use of a cold-draw (extrusion) process.

Acceptability of EP1.1.1.3: Evidence available to the INPRO assessor that demonstrates increased quality of manufacturing

and construction of the INS in comparison to existing designs.

INPRO Manual

2


Overview

1. Welding Technology Development

2. Other Manufacturing Technology

3

Manufacture technology such as welding, water jet peening and large/small size machining have been developed to increase the quality of manufacture.




4


Target of the Welding Technology Development

5

� To Minimize Deformation after Welding

� To Suppress Residual Stress to minimize the SCC Risk

(To Improve the Stress Distribution at the Welding Part)

� To Improve the Reliability

� To Improve the Work Efficiency and Work Environment

Precise Welding Structures with - Higher Reliability and Accuracy- Lower Maintenance Requirement

SCC: Stress Corrosion Cracking

Example of Reactor Internals


Development of Welding Method

6

Reliability

Efficiency

Conventional

Arc Welding

GMAW

Automatic

GMAW

Laser +Arc（（（（GMAW/GTAW））））Hybrid Welding

Laser Welding

70´s1960´s 80´s 90´s 2000´s

Laser MIG Hybrid

+ =

Hybrid Welding


Development of Narrow Gap Welding

7

The latest welding technologies in the world are

continuously studied and developed by Hitachi.

For many years, Narrow Gap Welding Technology have been

developed to increase reliability and reduce welding cost.

1970 1980 1990 2000 2010

years

V-shape groove

Narrow Gap Groove

Super Narrow

Gap Groove

Limited of GTAW

LASER Welding

Narrower

Gap Groove

Gro

ove

cross

sec

tion

nar

row

wid

e GTAWSMAW or GTAW


Welding Technologies for ABWR RPV

8

Narrow Gap MIG Welding

Hot Wire Switching TIG(HST) Welding

Single Layer Stainless Steel Cladding by ESW

Automatic TIG Welding of CRD Stub Tubes

Small Weld Deposit and High Toughness by Low Heat Input

Weld Cross Section

SAW

Narrow MIG

High Efficiency & High Quality TIG Welding

Electro Slag Welding by 150 mm Width Wide Strip

Full Automatic 3-D Welding

Machine Developed by BHK

Base Material4mm

150mm

Stainlesscladding

Conventional SMAW

Automatic TIG Welding




9


WJP is the Application after welding to improve the Stress distribution of Welded Part

10

Establish the residual stress of

the welded part surface into

compression side

-800

-600

-400

-200

0

200

400

600

0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4

Resid

ual stress σ

y (M

Pa)

SUS304

SUS316L

NCF600

●

▲

■

WJP Not peening Peening

○

△

□

Distance from surface Z (mm)

ＲｅｓｉｄｕａｌＳｔｒｅｓｓ

Ｃｏｍｐｒｅｓｓｉｏｎ

← →

Ｔｅｎｓｉｏｎ

ＤｉｓｔａｎｃｅｆｒｏｍＳｕｒｆａｃｅ

Higher Resistance to SCCHigh pressure water jet with cavitations hitting welded part

Development of Water Jet Peening


Improvement of Large Size Machining

11

Low Productivity with Manual

Operation

Improve Productivity with NC

Operation and High-speed type

Cutting tool.

Enlargement and Improve

Productivity with High

accuracy and multifunction

1978

Products Machined by Newest

Shroud Head Shroud

Products Machined by Newest

Equip.Hatch Dryer

1982

2008


Improvement of Small Size Machining

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-Decrease Machining Lead time -Increase Machining Capacity -Improve Machining Quality

1st NC Lathe 2nd Machining Center 3rd NC Lathe

Integrated Mill Turn Center

Only 1 Step

BeforeImprovement

AfterImprovement

Integrated Mill Turn Center can:


� Manufacture technology such as welding, water jet peeningand large/small size machining have been developed to increase the quality of manufacture for ABWR.

� For many years, Narrow Gap Welding Technology have been developed to increase reliability and reduce welding cost.

� Water Jet Peening achieves higher resistance to Stress Corrosion Cracking

� In conclusion, ABWR is evaluated to meet AC1.1.1.3.

Summary

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Documents

Quality of manufacture and construction - Atoms for … of manufacture and construction Every weld in a pipe or vessel could be a source of failure; ... Narrow Gap MIG Welding Hot