ASME B16.18-2021 pdf – Cast Copper Alloy Solder Joint Pressure Fittings.
2.3 QuaLity System
Requirements relating to the product manufacturer’s quality system programs are described In Nonmandatory Appendix C
3.1 Rating of Filling and of Joint
The Internal pressure—temperature ratings of the fittings are shown in Table 3.1-1.
The internal pressure—temperature rating for a solder joint fitting is dependent not only on fitting and tube strength, but also on the composition of the solder used for the ulnt and selection of valves and appurtenances.
The internal pressure—temperature rating otthe system shall be the lowest of the values shown in Table 11-1. the solder joint, and those of the tube. valves, or appurtenances,
The maximum recommended pressure—temperature ratings for solder joints using the dimensions of Table 8.2-2, made with typical commercial solders, are given in Nonmandatory Appendix A.
3.2 Bursting Strength
Burst strength at 73°F ± 5°F (23CC ±2°C) shall be not less than 4 times the 1OOF (38°C) internal working-pressure rating shown in Table 3.1-1. For reducing fittings, the applicable Internal working pressure shall be that of the largest size of end connection,
The size of the fittings shown in Table 8.2-2 and Table A-i corresponds to standard water tube size as shown in ASTM B88, Standard Specification for Seamless Copper Water Tube- The size of the threaded ends corresponds to nominal pipe size as shown in
ANSI/ASME 8120.1.
Fittings are designated by the size of the openings in the sequence Illustrated In Figure 4-1.
The following symbols are used to designate the type of fitting end:
C solder-joint fitting end made to receive copper tube diameter (lemale)
F = Internal ANSI standard taper pipe thread (female) NPT
8.2 Linear Dimensions
An inspection tolerance as shown in Table 8.2-1 shall be allowed on center-to-shoulder, center-to-center, center- to-threaded-end, and shoulder-to-threaded-end dimensions on all fittings having female solder (solder cup) ends, and on center-to-solder-end and solder-to- threaded-end dimensions on all fittings having male solder (fitting) ends.
Coupling inspection limits for shoulder-to-shoulder and shoulder-to-end dimensions shall be double those shown in Table 8.2-i, except that the minus tolerance applied to dimensions MN. and Win Tables 8,2-3 shall not result in a dimension less than 0.06 in. (1.5 mm) ror sizes ‘4 through 1 in.. inclusive, or a dimension less than 0.09 in. (2.3 mm) br the larger sizes.
The largest opening in the fitting governs the tolerance to be applied to all openings.
Tables 8.2-2 through 82-18 offer dimensions for pressure fittings covered by this Standard.
8.3 OvaLity
Maximum ovaifty shall not exceed 1% or the maximum diameters shown in Table 8.2-2. The average of the maximum and minimum diameters must be within the dimensions shown in the table.
8.4 Gaging of SoLder Joint Ends
8.4.1 Standard Gaging Method. The standard method of gaging the diameter tolerances for male and female ends shall be by the use of plain plug and ring gages designed to hold the product within the limits established In Table 8.2-2.
8.4.2 OptionaL Gaging Method. For gaging the diameter tolerance of male and female ends, the manufacturer may use direct reading instruments instead of ring and plug gages as specified in para. 8.4.1. When gaging the diameters of male and female ends using direct reading instruments, refer to para. 8.3.
8.5 Standard Gaging Method of Threaded Ends
The standard method of gaging the external and internal threaded ends shall be in accordance with the require’ ments of ANSI/ASME 11L20.1.
8.6 ALignment
The maximum-allowable deviation in the angular alignment of any opening shall be 0.06 in/ft (5mm/m) (0.5%).
9.1 Thread Type
Fitting threads shall be right hand, conforming to ANSI/ ASME HI .20.1. Pipe Threads, General Purpose (Inch). They shall be taper threads (NPT).
9.2 Countersink or Chamfer
All Internal threads shall be countersunk a distance not less than one-half the pitch of the thread at an angle approximately 45 deg with the axis of the thread, and all external threads shall be chamfered at an angle of 30 dcg to 45 deg From the axis, for easier entrance In making a joint and protection of the thread. Countersinking and chamfering shall be concentric with the threads.
9.3 Threading ToLerances
Tolerance for an internal threaded end having an internal shoulder shall be from the gage reference point (notch) to one turn smalL Tolerance for an internal threaded end without shoulder and for an external threaded end shall be from one turn small to one turn brge.