1、CASECASES OF ASME BOILER AND PRESSURE VESSEL CODE2344-1Approval Date:January 3,2006The ASME Boiler and Pressure Vessel Standards Committee took action toeliminate Code Case expiration dates effective March 11,2005.This means thatall Code Cases listed in this Supplement and beyond will remain availab
2、le foruse until annulled by the ASME Boiler and Pressure Vessel Standards Committee.Case2344-1TABLE 1Use of Sand Cast Aluminum Alloy A356.0,T6 Temper,CHEMICAL REQUIREMENTSfor the Manufacture of Hot Water Heating BoilersElementComposition,%(by weight)Under Part HCSection IVSilicon6.5-7.5Iron0.20maCop
3、per0.20 max.Inquiry:May aluminum alloy A356.0 sand castings inManganese0.10mathe T6 temper meeting the chemical composition andMagnesium0.25-0.40mechanical properties given in Tables 1 and 2 and otherZinc0.10 max.requirements of ASTM B 26/B 26M-97 be used in SectionTitanium0.20 max.IV,Part HC,constr
4、uction of heating boilers?Others0.05 max.eachOthers total0.15max.AluminumremainderReply:It is the opinion of the committee that aluminumalloy A356.0 sand castings in the T6 temper meeting theTABLE 2chemical composition and mechanical properties given inMECHANICAL PROPERTIESTables I and 2 and other r
5、equirements of ASTM B 26/B26M-97 may be used in Section IV,Part HC,constructionTensile strength,min.,ksi34.0(235MPa)of heating boilers,under the following conditions:Yield strength,min.,ksi24.0(165MPa)Elongation in 2 in.(50 mm),min.,%3.5(a)No welding is permitted.(b)In lieu of Section IV,HC-200 thro
6、ugh HC-213,allapplicable requirements of ASTM B 26/B 26M-97 andTables I and 2 of this Case shall apply.The footnotes(e)Proof testing to establish design pressure is requiredapplicable to Tables 1 and 2 of ASTM B 26/B 26M-97and shall comply with HG-501 and HG-502.3,except thatapply to Tables I and 2
7、of this Case.in the equation in HG-502.3,the specified minimum tensile(c)Maximum water temperature shall be 200F(95C).strength at room temperature shall be 34,000 psi(235(d)All other applicable parts of Section IV shall applyMPa)and the design factor shall be 7 in lieu of 5.exceptexcept HC-401 and H
8、C-402.In lieu of procedures(f)All boiler parts or sections shall be built accordingof HC-410,the assembled boiler may be hydrostaticallyto the Material Specification requirements.Each boilertested at 2%times the maximum allowable working pres-section,including end and intermediate cored sections.sur
9、e,provided the test pressure does not exceed 1 timesshall show the following data cast in letters or numeralsthe design pressure of the next limiting part.If 2%timesat least%6 in.(8 mm)high:hydro exceeds 1 times the design pressure of any part of(/the Material Specification identification numberthe
10、completed vessel,then the 2%times test is only per-(2)the boiler or parts manufacturers name or accept-formed on the casting,and the assembled boiler must beable abbreviation,preceded by the words Certified bytested at 1.or“Cert.by”The Committees function is to establish rules of safety.relating onl
11、y to pressure integrity.governing the construction of boilers,pressure vessels,transport tanks andnuclear components,and inservice inspection for pressure integrity of nuclear components and transport tanks,and to interpret these rules when questions ariseregarding their intent.This Code does not ad
12、dress other safety issues relating to the construction of boilers,pressure vessels.transport tanks and nuclear components.and the inservice inspection of nuclear components and transport tanks.The user of the Code should refer to other pertinent codes,standards,laws,regulations orother relevant documents.1(2344-1)。with ASMENot to R0MDT-Norfolk Naval Shipyard/5901638100No roproduction or notworking permitled without liconso from IHS