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Re: [MW:7054] welding tube to tubesheet

By Materials & Welding
Hi,
You follow as below.

QW-202.6 Tube-to-Tubesheet Qualification.

When the applicable Code Section requires the use of QW-193

for tube-to-tubesheet demonstration mockup qualification

tests, QW-193.1 shall apply. If specific qualification test

requirements are not specified by the applicable Code Section,

tube-to-tubesheet welds shall be qualified with one

of the following methods:

(a) groove welds per the requirements of QW-202.2

and QW-202.4

(b) a demonstration mockup per the requirements of

QW-193.1

(c) fillet welds per the requirements of QW-202.2(c)

(for nonpressure retaining tube-to-tubesheet welds only)

andas per ASME Sec.VIII,Div.1
 

UW-20 TUBE-TO-TUBESHEET WELDS

UW-20.1 Scope. These rules provide a basis for establishing

weld sizes and allowable joint loads for full strength

and partial strength tube-to-tubesheet welds.

UW-20.2 Definitions

UW-20.2(a) Full Strength Weld. A full strength tubeto-

tubesheet weld is one in which the design strength is

equal to or greater than the axial tube strength, Ft. When

the weld in a tube-to-tubesheet joint meets the requirements

of UW-20.4, it is a full strength weld and the joint does

not require qualification by shear load testing. Such a weld

also provides tube joint leak tightness.

UW-20.2(b) Partial Strength Weld. A partial strength

weld is one in which the design strength is based on the

mechanical and thermal axial tube loads (in either direction)

that are determined from the actual design conditions.

The maximum allowable axial load of this weld may be

determined in accordance with UW-20.5, Appendix A, or

UW-18(d). When the weld in a tube-to-tubesheet joint

meets the requirements of UW-20.5 or UW-18(d), it is a

partial strength weld and the joint does not require qualification

by shear load testing. Such a weld also provides

tube joint leak tightness.

UW-20.2(c) Seal Weld. A tube-to-tubesheet seal weld

is one used to supplement an expanded tube joint to ensure

131

leak tightness. Its size has not been determined based on

axial tube loading.

UW-20.3 Nomenclature. The symbols

UHX-15 TUBE-TO-TUBESHEET WELDS

Tube-to-tubesheet welds shall be in accordance with

UW-20, as applicable. Tube-to-tubesheet welds not covered

by UW-20 shall be in accordance with U-2(g).

.Conclusion.
 
If your tube to tubesheet joint fall in UW20.4 and 20.5 you no need to qualify with shear load test and existing qualification shall be used.If it is of Fillet weld type,then you have to follow Appemdix-A,and need to qualify with shear load test.
 
Thanks & Regards,
 
(karthik)
Karthikeyan.S
QA/QC Manager
Getabec Energy Co.,Ltd.
379,Moo6,Soi8,Nikhomphatana,
Rayong-21180,
Thailand.
Phone: 0066 38 897035-8 (Off)
Fax: 0066 38 897034
Hand Phone: 0066 892512282


--- On Fri, 9/17/10, skrie85 <skrie85@yahoo.com> wrote:

From: skrie85 <skrie85@yahoo.com>
Subject: [MW:7052] welding tube to tubesheet
To: materials-welding@googlegroups.com
Date: Friday, September 17, 2010, 10:46 AM

I want to welding tube to tubesheet. I have qualified GTAW before by using plate (not mock-up test). Can I welding tube to tubesheet by using qualification of GTAW?

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