ASME B16.15-2006 pdf – Cast Copper Alloy Threaded Fittings Classes 125 and 250.
The temperature shown for the corresponding pressure rating shall be the material temperature of the pressure-retaining structure. It may be assumed that the material temperature is the same as the fluid tempera. tuie, Use of a pressure rating at a material temperature other than that of the contained fluid is the responsibility of the user and subject to the requirements of any applicable codes and regulations.
2.3 LimItations
Use of cored plugs and hexagon or octagon head bushings should be limited to Class 125 pipe fittings. Solid plugs and face bushings are recommended for use with Class 250 pipe fittings.
3 SIZE
3.1 NomInal PIpe Size
The size of the pipe fittings scheduled in the following tables is identified by the corresponding nominal pipe size (NT’S),’
3.2 ReducIng Sizes
Ln the case of reducing tec, crosses, and Y branches (laterals), the NT’S of the largest run opening shall be given first, followed by the NPS of the opening at the opposite end of the run. Where the pipe fitting is a tee or Y branch (lateral), the NI’S of the outlet is given last. Where the pipe fining is a cross, the largest side-outlet opening Lx the third dimension given, followed by the opening opposite. The straight line sketches of Fig. I illustrate how the reducIng pipe fittings are read.
4 MARKING
4.1 Class 125 Fitting
Each Class 125 pipe fitting shall be marked for identification with the manufacturer’s name or trademark.
6 THREADING
6.1 Types of Threads
All pipe fittings shalt be threaded with ANSI/ ASME B1.20.1 general purpose pipe threads and shall have taper threads, except wrought couplings (]hles 2 and 1-2), wrought caps (Tables 3 and 1-3). and wrought bushings (Tables 4 and 1-4) in NI’S k, NI’S ). NI’S cb and NPS which may have straight internal threads.
6.2 Tolerances
The permissible tolerance in taper threading shall be limited to one turn large or one turn small from the gaging face on ring and gaging notch on plug, when using working gages. The variations in straight threading shall be limited to one and one-half turns brge or small from gaging notch cii plug, when using taper pipe thread working gage. The reference point br gaging internal Fittings threads depends upon the chamfer diameter. When the internal chamfer diameter exceeds the major diameter of the internal thread, the reference point is the last thread scratch cii the chamfer cone. When the internal chamfer diameter dors not exceed the major diameter of the internal thread, the reference point is the end of the fitting.
6.3 CountersInk or Chamfer
All internal threads shall not be countersunk a distance of less than one-hall the pitch of the thread at an angle of approximately 45 deg with the axis of the thread. and all external threads shall be chamfered at an angle of 30 deg to 45 deg with the axis, both for the purpose of easier entrance in making a joint, and for protection of the thread. Countersinking and chamfering shall be concentric with the threads.
6.4 Length of Thread
The length of threads specified in all tables hall he measured to include the countersink or chamfer.
6.5 Alignment
The maximum allowable variation in the alignment of threads of all openings of threaded pipe fittings shall be I mm/rn (0.06 in./lt) or 0.5%.
6.6 BushIngs
All bushings shalt be threaded with American National Standard taper pipe threads, except those sizes of wrought bushings listed In para. 6.1 which may have straight internal threads. Caging of all threads shall comply with ANSI/ASME ll.2O.I except those sizes of outside bushings where the external thread lengths are shorter than required by ANSI/ASME B120,1. These bushings should be threaded so that when making up the joint, the shoulder of the head will not interfere.