Hi, You follow as below. QW-202.6 Tube-to-Tubesheet Qualification. When the applicable Code Section requires the use of QW-193for 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-202.2and QW-202.4 (b) a demonstration mockup per the requirements ofQW-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 establishingweld 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. Whenthe 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 strengthweld 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 weldis 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:
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