Abstract： ASME B16.15:2006 pdf download.Cast Copper Alloy Threaded Fittings Classes 125 and 250. 6 THREADING 6.1 Types of Threads All pipe fittings shall be threaded with ANSI/ ASME 131.20.1 general purpose pipe threads and shall have taper threads....

ASME B16.15:2006 pdf download.Cast Copper Alloy Threaded Fittings Classes 125 and 250.

6 THREADING

6.1 Types of Threads

All pipe fittings shall be threaded with ANSI/ ASME 131.20.1 general purpose pipe threads and shall have taper threads. except

wrought couplings (Tables 2 and 1-2). wrought caps tTahks 3 and 1-3). and wrought bushings (rabIes 4 and 1-4) in NI’S k. NI’S M’S and NI’S 3, 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 p1ug, when using working gages. The variations in straight threading shall be limited to one and one-hall turns

Large or small from gaging notch on plug. when usrng taper pipe thread working gage. The reference point for gaging internal

fittings threads depends upon the chamfer diameter. When the internal chamfer diameter etsds th niaor diameter of the internal

thread, the nference point is the last thread scratch on the chamfer cone. When the internal chamfer diameter does not exceed the

maior diameter of the internal thread, the reference potnt is the end of the fitting.

6.3 Countersink or Chamfer

All internal threads shall not be countersunk a distance of less than oiw-half 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 shall be 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/m (0.06 in./ft) or 0.5%.

Recommended：