ASME B1.20.2M:2006 pdf download Pipe Threads, 60 deg, General Purpose
SCOPE
This Standard specifies the designations, dimensionsand tolerances and establishes a verification system fo60 deg included angle pipe threads. It is applicable forgeneral purpose pipe and fitting connections. Wherepressure-tight joints are required, it is intended thattaper pipe threads conforming to this Standard be madeup wrench-tight with a sealant. To prevent galling oncertain piping materials such as stainless steel, the seaant should contain a lubricant.
Internal parallel (straight) pipe threads, series NPSCare used with external taper pipe threads, series NPT.Internal taper pipe threads, series NPT, are used withexternal taper pipe threads, series NPT
2 REFERENCE AND SYMBOLS
2.1 Reference Standard
The following publication is referenced in this Standard. The latest edition shall apply.ASME B1.20.1,Pipe Threads, General Purpose(InchPublisher: The American Society of MechanicalEngineers(ASME)Three Park AvenueNew YorkNY 10016-5900:Order Department:22 Law DriveP.O.Box 2300Fairfield,NJ 07007-2300
2.2 Symbols
The following symbols are used (see Fig. 1):D p outside diameter of pipeEo p basic pitch diameter at small end of externalthread (or end of pipe)E p basic pitch diameter at plane of hand-tightengagement length (L1),external thread, largeend of internal threadE2 p basic pitch diameter at plane of effective threadlength (L2), external threadE p basic pitch diameter at plane of wrench-tight
engagement
Es p basic pitch diameter at LsKo p basic minor diameter at small end of externathread (or end of pipe)Li p length of hand-tight engagement betweeninternal and external threadsl2 p length of effective thread, external threadL3 p length of thread beyond L1 allowingwrench-tight engagement, internal thread; alsowrench makeup
3 TAPER PIPE THREAD FORM
3.1 Thread Profile
The form of thread profile specified in this Standardshall be known as the Standard Taper Pipe Thread Form.The relations as specified herein for form of thread andgeneral notation are shown in Fig. 2.
3.2 Angle of ThreadThe angle between the sides of the thread is 60 degwhen measured in an axial plane. The line bisecting thisangle is perpendicular to the axis.
3.3 Truncation and Thread HeightThe height, H, of the sharp V thread is
Hp0,866025P
wherePp pitch of thread
The basic maximum height of the truncated thread, h,(see Fiq. 2) is based on factors entering into the manufacture of cutting tools and the making of tight joints.
Maximum hp 0,800000P
The crest and root of pipe threads are truncated aminimum of 0033000P The maximum depth of truncation for the crest and root of these pipe threads will befound in Table 1. The crest and roots of external andinternal threads may be truncated either parallel to thepitch line or parallel to the axis.
The illustration in Fig. 2, giving a sectional view ofthis standard thread form, represents the truncatedthread form by a straight line. However, when closelyexamined, the crests and roots of commercially manufactured pipe threads appear slightly rounded. When crestsand roots of threading tools or chasers lie within thelimits shown in Table 1, the pipe threads of productsproduced by such means are accentable on the basis ofin-process control.