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ASTM A999/A999M-12
Standard Specification for Alloy and Stainless Pipe
16. Straightness
16.1 The finished pipe shall be reasonably straight.
16.2 For metal-arc welded pipe, the maximum deviation from a 10-ft [3.0-m] straight edge placed so that both ends are in contact with the pipe shall be 1⁄8 in. [3.2 mm]. For metal-arc welded pipe with lengths shorter than 10 ft. [3.0 m], this maximum deviation shall be prorated with respect to the ratio of the actual length to 10 ft. [3.0 m]
| ASTM A999/A999M - 12 | ||||
| Standard Specification for General Requirements for Alloy Stainless Steel Pipe | ||||
| Table 1-Permissible Variations in Outside Diameter | ||||
| NPS / DN Designator | Over (inches) | Over (mm) | Under(inches) | Under (mm) |
| 1/8" to 1 1/2" incl | 0.015 | 0.4 | 0.031 | 0.8 |
| (6mm to 40mm) | ||||
| Over 1 1/2" to 4" incl | 0.031 | 0.7 | 0.031 | 0.8 |
| (40mm to 100mm) | ||||
| Over 4" to 8" incl | 0.062 | 1.6 | 0.031 | 0.8 |
| (100mm to 200mm) | ||||
| Over 8" to 18" incl | 0.093 | 2.4 | 0.031 | 0.8 |
| (200mm to 450mm) | ||||
| Over 18" to 26" incl | 0.125 | 3.2 | 0.031 | 0.8 |
| (450mm to 650mm) | ||||
| Over 26" to 34" inc | 0.156 | 4.0 | 0.031 | 0.8 |
| (450mm to 850mm) | ||||
| Over 34" to 48" incl | 0.187 | 4.8 | 0.031 | 0.8 |
| (850mm to 1200mm) | ||||
Minimum Wall thickness on inspection for nominal (average) pipe wall thickness is covered under Appendix X1. of ASTM A999/A999m – 12
The following equation, may be applied to calculate minimum wall thickness from nominal (average) wall thickness:
tn x 0.875 = tm
where:
tn = nominal (average) wall thickness,
and
tm = minimum wall thickness
The nominal plain end mass, in kilograms per meter, is calculated using the following formula:
Wpe = 0.0246615(D – t)t
where:
D = outside diameter to the nearest 0.1 mm for outside diameters that are 16 in. (406.4 mm) and smaller and to the nearest 1.0 mm for outside diameters larger than 16 in. (406.4mm) (the symbol D is to be used for OD only in mathematical equations or formulas)
and;
Wpe = nominal plain end mass, rounded to the nearest 0.01 kg/m
and;
t = specified wall thickness, rounded to the nearest 0.01 mm
ASTM A999/A999M-12
Standard Specification for Alloy and Stainless Pipe
16. Straightness
16.1 The finished pipe shall be reasonably straight.
16.2 For metal-arc welded pipe, the maximum deviation from a 10-ft [3.0-m] straight edge placed so that both ends are in contact with the pipe shall be 1⁄8 in. [3.2 mm]. For metal-arc welded pipe with lengths shorter than 10 ft. [3.0 m], this maximum deviation shall be prorated with respect to the ratio of the actual length to 10 ft. [3.0 m]
| ASTM A999/A999M - 12 | ||||
| Standard Specification for General Requirements for Alloy Stainless Steel Pipe | ||||
| Table 1-Permissible Variations in Outside Diameter | ||||
| NPS / DN Designator | Over (inches) | Over (mm) | Under(inches) | Under (mm) |
| 1/8" to 1 1/2" incl | 0.015 | 0.4 | 0.031 | 0.8 |
| (6mm to 40mm) | ||||
| Over 1 1/2" to 4" incl | 0.031 | 0.7 | 0.031 | 0.8 |
| (40mm to 100mm) | ||||
| Over 4" to 8" incl | 0.062 | 1.6 | 0.031 | 0.8 |
| (100mm to 200mm) | ||||
| Over 8" to 18" incl | 0.093 | 2.4 | 0.031 | 0.8 |
| (200mm to 450mm) | ||||
| Over 18" to 26" incl | 0.125 | 3.2 | 0.031 | 0.8 |
| (450mm to 650mm) | ||||
| Over 26" to 34" inc | 0.156 | 4.0 | 0.031 | 0.8 |
| (450mm to 850mm) | ||||
| Over 34" to 48" incl | 0.187 | 4.8 | 0.031 | 0.8 |
| (850mm to 1200mm) | ||||
Minimum Wall thickness on inspection for nominal (average) pipe wall thickness is covered under Appendix X1. of ASTM A999/A999m – 12
The following equation, may be applied to calculate minimum wall thickness from nominal (average) wall thickness:
tn x 0.875 = tm
where:
tn = nominal (average) wall thickness,
and
tm = minimum wall thickness
The nominal plain end mass, in kilograms per meter, is calculated using the following formula:
Wpe = 0.0246615(D – t)t
where:
D = outside diameter to the nearest 0.1 mm for outside diameters that are 16 in. (406.4 mm) and smaller and to the nearest 1.0 mm for outside diameters larger than 16 in. (406.4mm) (the symbol D is to be used for OD only in mathematical equations or formulas)
and;
Wpe = nominal plain end mass, rounded to the nearest 0.01 kg/m
and;
t = specified wall thickness, rounded to the nearest 0.01 mm
ASTM A999/A999M-12
Standard Specification for Alloy and Stainless Pipe
16. Straightness
16.1 The finished pipe shall be reasonably straight.
16.2 For metal-arc welded pipe, the maximum deviation from a 10-ft [3.0-m] straight edge placed so that both ends are in contact with the pipe shall be 1⁄8 in. [3.2 mm]. For metal-arc welded pipe with lengths shorter than 10 ft. [3.0 m], this maximum deviation shall be prorated with respect to the ratio of the actual length to 10 ft. [3.0 m]
| ASTM A999/A999M - 12 | ||||
| Standard Specification for General Requirements for Alloy Stainless Steel Pipe | ||||
| Table 1-Permissible Variations in Outside Diameter | ||||
| NPS / DN Designator | Over (inches) | Over (mm) | Under(inches) | Under (mm) |
| 1/8" to 1 1/2" incl | 0.015 | 0.4 | 0.031 | 0.8 |
| (6mm to 40mm) | ||||
| Over 1 1/2" to 4" incl | 0.031 | 0.7 | 0.031 | 0.8 |
| (40mm to 100mm) | ||||
| Over 4" to 8" incl | 0.062 | 1.6 | 0.031 | 0.8 |
| (100mm to 200mm) | ||||
| Over 8" to 18" incl | 0.093 | 2.4 | 0.031 | 0.8 |
| (200mm to 450mm) | ||||
| Over 18" to 26" incl | 0.125 | 3.2 | 0.031 | 0.8 |
| (450mm to 650mm) | ||||
| Over 26" to 34" inc | 0.156 | 4.0 | 0.031 | 0.8 |
| (450mm to 850mm) | ||||
| Over 34" to 48" incl | 0.187 | 4.8 | 0.031 | 0.8 |
| (850mm to 1200mm) | ||||
Minimum Wall thickness on inspection for nominal (average) pipe wall thickness is covered under Appendix X1. of ASTM A999/A999m – 12
The following equation, may be applied to calculate minimum wall thickness from nominal (average) wall thickness:
tn x 0.875 = tm
where:
tn = nominal (average) wall thickness,
and
tm = minimum wall thickness
The nominal plain end mass, in kilograms per meter, is calculated using the following formula:
Wpe = 0.0246615(D – t)t
where:
D = outside diameter to the nearest 0.1 mm for outside diameters that are 16 in. (406.4 mm) and smaller and to the nearest 1.0 mm for outside diameters larger than 16 in. (406.4mm) (the symbol D is to be used for OD only in mathematical equations or formulas)
and;
Wpe = nominal plain end mass, rounded to the nearest 0.01 kg/m
and;
t = specified wall thickness, rounded to the nearest 0.01 mm
FAQ
What is What is A999M-12?
ASTM A999M-12 is a specification for general requirements for alloy and stainless steel pipe which is an international standard that is similar to the ASTM A999 standard that we discussed earlier. The “M” in A999M indicates that it is a metric measurement standard, which specifies the dimensions and tolerances for metric pipes used in international applications.
The ASTM A999M-12 standard covers a wide range of topics related to alloy and stainless steel pipe, and provides guidelines for the chemical composition, heat treatment, mechanical properties, and other factors that impact the quality and performance of the pipe. It also specifies the testing and inspection requirements, including hydrostatic testing, non-destructive testing, and dimensional inspection, to ensure that the pipes meet the required standards.
In addition, ASTM A999M-12 provides the dimensions and tolerances for metric pipes, including wall thickness, diameter, and out-of-roundness. It also provides guidance for marking and packaging the pipes for shipment and storage.
What is ASTM A999?
STM A999 is a standard specification for general requirements for alloy and stainless steel pipe. This standard covers a wide range of topics related to alloy and stainless steel pipe, including the manufacturing process, testing requirements, and dimensions and tolerances.
ASTM A999 specifies the requirements for pipes made from different grades of steel, including austenitic, ferritic, and martensitic steel alloys, as well as duplex and super duplex stainless steel. The standard provides detailed requirements for the chemical composition, heat treatment, mechanical properties, and other factors that impact the quality and performance of the pipe.
This standard also covers the testing and inspection requirements for alloy and stainless steel pipes, including hydrostatic testing, non-destructive testing, and dimensional inspection. It specifies the procedures for testing the chemical composition, mechanical properties, and other characteristics of the pipe to ensure they meet the required standards.