ASME B16.3-2011 pdf download

ASME B16.3-2011 pdf download.Malleable lronThreaded Fittings Classes 150 and 300.
2 GENERAL
2.1 References
Standards and specifications adopted by reference in this Standard are shown in Mandatory Appendix 11. It is not considered practical to identify the specific edition of each referenced standard and specification in the text. Instead, the specific editions of the referenced standards and specifications are listed in Mandatory Appendix II.
2.2 Quality Systems
Requirements relating to the product manufacturers’ quality system programs are described in Nonmandatory Appendix A.
2.3 Relevant Units
This Standard states values in both SI (Metric) and U.S. Customary units. These systems of units are to be regarded separately as standard. Within the text, the U.S. Customary units are shown in parentheses or in separate tables that appear in Mandatory Appendix I. The values stated in each system are not exact equivalents; therefore, it is required that each system of units be used independently of the other. Combining values from the two systems constitutes nonconformance with the Standard.
2.4 Service Conditions
Criteria for selection of materials suitable for particular fluid service are not within the scope of this Standard.
(d) Class 300 street elbows are not recommended for pressures above 600 psi.
4 SIZE
4.1 Nominal Pipe Size
As applied in this Standard, the use of the phrase “nominal pipe size” or the designation NPS followed by a dimensionless number is for the purpose of identifying the end connection of fittings. The number is not necessarily the same as the fitting inside diameter.
4.2 Reducing Fittings
For reducing tees, crosses, and Y-branches (laterals), the size of the largest run opening shall be given first, followed by the size of the opening at the opposite end of the run. Where the fitting is a tee or Y-branch (lateral), the size of the outlet is given last. Where the fitting is a cross, the largest side-outlet opening is the third dimension given, followed by the opposite opening. The straiht-line sketches of Fig. I illustrate how the reduc2
ing fittings are read.
5 MARKING
5.1 Class 150 Fittings 4 x
Each Class 150 fitting shall be marked for identifica
tion with the manufacturer’s name or trademark.
5.2 Class 300 Fittings 7 I
Each Class 300 fitting shall be marked for identification with TF
(a) the manufacturer’s name or trademark
(b) the numerals “300” milli
(c) the letters “MI” to designate malleable iron fittir
(d) the size are
(e) other markings as permitted by MSS SP-25
6.1 MalleabLe Iron
The chemical and physical properties of the castings shall be in accordance with ASTM A197. The manufacturer shall be prepared to certify that the product has been so produced.
6.2 Steel
Class 150 couplings and caps in NPS 1/4, and 3’ may It be made from steel rod or bar with a minimum yield una strength of 30 ksi at the manufacturer’s option.
8.2 Tolerances
Variations 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 large or small from the gaging notch on plug when using a taper pipe thread Working gage. The reference point for 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 on the chamfer cone. When the internal chamfer diameter does not exceed the major diameter of the internal thread, the reference point is the end of the fitting (see Fig. 2).
8.3 Countersink or Chamfer
For the purpose of easier entrance in making a joint and for protection of the thread, all internal threads shall be countersunk a distance of not less than one-half the pitch of the thread at an angle of approximately 45 deg with the axis of the thread; all external threads shall be chamfered at an angle of 30 deg to 45 deg with the axis. Countersinking and chamfering shall be concentric with the threads.