ASME B16.9 is a standard for butt weld pipe fittings including elbow, tee, cross, cap, reducer, and etc.
This Standard covers overall dimensions, tolerances, ratings, testing, and markings for factory-made wrought buttwelding fittings in sizes NPS 1 / 2 through NPS 48 (DN 15 through DN 1200). It covers fittings of any producible wall thickness. This standard does not cover low pressure corrosion resistant buttwelding fittings. See MSS SP-43, Wrought Stainless Steel Butt-Welding Fittings.
Short radius elbows and returns, which were previously included in ASME B16.28-1994, are included in this standard.
B16.9 is to be used in conjunction with equipment described in other volumes of the ASME B16 series of standards as well as with other ASME standards, such as the Boiler and Pressure Vessel Code and the B31 Piping Codes.
ASME B16.9 Size
NPS, followed by a dimensionless number, is the designation for nominalfitting size.NPS is related to the reference nominal diameter, DN, used in international standards. It has the Same Dimension As ASME B36.10/B36.19
ASME B16.9 Standard Marking
Each fitting shall be permanently marked to show the following:
(a) manufacturer’s name or trademark
(b) material identification, either the ASTM or ASME grade designation
(c) schedule number1 or nominal wall thickness in mm
(d) size — the nominal pipe size (NPS) identification
number related to the end connections shall be used
(e) compliance—see para. 4.4 for standard and special fitting marking
A manufacturer may supplement these mandatory markings with others, including a DN size designation, but confusion with the required marking shall be avoided.
ASME B16.9 Material
Wrought fittings covered by this Standard shall be in accordance with ASTM A234, ASTM A403, ASTM A420, ASTM A815, ASTM B361, ASTM B363, ASTM B366, orthe corresponding specification listed in ASME BPVC,Section II. The term “wrought” denotes fittings made of
pipe, tubing, plate, or forgings.
Table 5-1 Material Groupings Group No. Material Standards
1 Carbon and low-alloy steels ASTM A234/A234M and ASTM A420/A420M
2 Austenitic and duplex stainless steels ASTM A403/A403M and ASTM A815/A815M
3 Nickel alloys ASTM B366/B366M
4 Aluminum alloys ASTM B361
5 Titanium alloys ASTM B363
ASME B16-9- Buttwelding Fittings Dimension
This Standard provides for a fixed position for the welding ends with reference to either the centerline of the fittings or the overall dimensions
ASME B16.9 SURFACE CONTOURS
Where adjacent openings in fittings are not in parallel planes, they shall be joined by a circular arc or radius on the external surfaces. The arc or radius may be terminated in tangents. Except as provided for block forgings (see section 5), the projected profile of external surfaces of Fifittings shall not have sharp intersections (corners) and/or collapsed arcs.
ASME B16.9 END PREPARATION
Unless otherwise specified, the details of the welding end preparation shall be in accordance with Table 8-1.Transitions from the welding bevel to the outside surface of the fitting and from the root face to the inside surface of the fitting lying within the maximum envelope shown in Figure 8-1 are at the manufacturer’s option, except as covered in Note (5) of Figure 8-1 or unless otherwise specifically ordered.
ASME B16.9 DIMENSION TOLERANCES
Tolerances for fittings are shown in Table 11-1 and apply to the nominal dimensions given in Tables 6.1-1 through 6.1-11. Where given in the tables, the
minimum and maximum dimensions are based on these tolerances. The listings with decimals do not imply precision measurement, such as use of vernier, micrometer, or electronic readout equipment.
Reference Standards
It is not considered practical to identify the specific edition of each standard and specification in the individual references. A product made comply with a prior edition of referenced standards and in all other respects conforming to this standard will be considered complied.
- ASME B16.5: Pipe Flanges and Flanged Fittings: NPS 1∕2 Through NPS 24 Metric/Inch Standard
- ASME B16.25: For Buttwelding Ends
- ASME B31: Code for Pressure Piping
- ASME B31.3: Process Piping
- ASME B36.10M, Welded and Seamless Wrought Steel Pipe
- ASME B36.19M, Stainless Steel Pipe
- ASME Boiler and Pressure Vessel Code
- ASTM A234/A234M-17, Specification for Piping Fittings of Wrought Carbon Steel and Alloy Steel for Moderate and High Temperature Service
- ASTM A403/A403M-16, Specification for Wrought Austenitic Stainless Steel Piping Fittings
- ASTM A420/A420M-16, Specification for Piping Fittings of Wrought Carbon Steel and Alloy Steel for LowTemperature Service
- ASTM A815/A815M-14e1, Specification for Wrought Ferritic, Ferritic/Austenitic and Martensitic Stainless Steel Piping Fittings
- ASTM A960/A960M-16a, Specification for Common Requirements for Wrought Steel Piping Fittings
- ASTM E29-13, Practice for Using Significant Digits in Test Data to Determine Conformance With Specifications
- ASTM B361-16, ASTM B363-14, ASTM B366/B366M-17: For other material metals. (Aluminum, Titanium, Nickel, and alloy).
