MSS SP-79

Abstract

This document establishes a Standard Practice for Socket Welding Reducer Inserts produced for a number of years by various manufacturers to varying dimensions although basically similar in principle. Users should note reducers furnished from existing stocks may have slightly different dimensions than shown in Table 3.Table 3M has been added to this 2011 edition for (SI) metric dimensioned fittings. Other (SI) metric dimensions and the 2010 Errata Sheet have also been incorporated into this 2011 edition. <br>Purpose To provide a Standard Practice establishing requirements for insert type fittings, which effectively, after welded installation, creates a socket welded reduced end fitting, such as Tee, 90 degree E11, Cross, 45 degree E11, Coupling, etc. <br>General This Standard Practice covers ratings, dimensions, tolerances, finish, marking and material requirements for socket welding reducer inserts for use with ASME B16.11, Class 3000 and 6000 socket welding fittings. U.S. customary unit dimensions for these reducer inserts are shown in Table 3 and (SI) metric dimensions are shown in Table 3M. <br>Fitting Sizes/Pipe Correlation - Fittings covered by this Standard Practice are shown in Table 1, by class, size range and correlation to the schedule number or wall designation of pipe for calculation of ratings. <br>Partial Compliance Fittings - Fittings with special dimensions and fittings made from non-standard materials may be designed and manufactured by agreement between the manufacturer and the purchaser, provided they are marked in accordance with the requirements for partial compliance fittings of Section 5.1.1 (e). <br>Service Conditions - Criteria for selection of fitting type and materials suitable for particular fluid service are not within the scope of this Standard Practice. <br>Welding - Except for the CAUTIONARY NOTE (Section 12) and the GAP RECOMMENDATIONS (Figure 1 and Figure 2), installation welding requirements are not within the scope of this Standard Practice. Installation welding shall be done in accordance with the applicable piping system into which the fittings are to be installed. <br><br> &#160;