ASTM A209/A209M
Standard Specification for
Seamless Carbon-Molybdenum Alloy-Steel Boiler and Superheater Tubes 
 
 
1. Scope
1.1 This specification covers several grades of minimum-wall-thickness, seamless, carbon-molybdenum alloy-steel,boiler and superheater tubes.
1.2 This specification covers tubes 1 ⁄ 2 to 5 in. [12.7 to 127mm] inclusive, in outside diameter and 0.035 to 0.500 in. [0.9 to 12.7 mm], inclusive, in minimum wall thickness.
1.3 An optional supplementary requirement is provided and,when desired, shall be so stated in the order.
1.4 The values stated in either inch-pound units or SI units are to be regarded separately as standard. Within the text, the SI units are shown in brackets. The values stated in each system are not exact equivalents; therefore, each system must be used independently ofthe other. Combining values from the two systems may result in nonconformance with the specification. The inch-pound units shall apply unless the “M”designation of this specification is specified in the order.
 

2. Referenced Documents
2.1 ASTM Standards:
A1016/A1016M Specification for General Requirements for Ferritic Alloy Steel, Austenitic Alloy Steel, and Stainless Steel Tubes
 
 
3. General Requirements
3.1 Product furnished under this specification shall conform
to the requirements of Specification A1016/A1016M, including any supplementary requirements that are indicated in the purchase order. Failure to comply with the general requirements of Specification A1016/A1016M constitutes nonconformance with this specification. In case of conflict with the requirements of this specification and Specification A1016/A1016M, this specification shall prevail.
 
 
4. Materials and Manufacture
4.1 Steelmaking Practice—The steel shall be killed.
4.2 The tubes shall be made by the seamless process and shall be either hot-finished or cold-finished, as specified.
4.3 HeatTreatment—Hot-finished tubes shall be heat treated at a temperature of 1200 °F [650 °C] or higher. Cold-finished tubes shall, after the final cold finishing, be heat treated at a temperature of 1200 °F [650 °C] or higher, or tubing may be furnished in the full-annealed, isothermal annealed, or normalized and tempered condition. If furnished in the normalized and tempered condition, the minimum tempering temperature shall be 1200 °F [650 °C].
 
 
5. Chemical Composition
5.1 The steel shall conform to the requirements given in Table 1.
 
TABLE 1 Chemical Composition Requirements

Element	Composition, %
	Grade T1	Grade T1a	Grade T1b
Carbon	0.10–0.20	0.15–0.25	0.14 max
Manganese	0.30–0.80	0.30–0.80	0.30–0.80
Phosphorus, max	0.025	0.025	0.025
Sulfur, max	0.025	0.025	0.025
Silicon	0.10–0.50	0.10–0.50	0.10–0.50
Molybdenum	0.44–0.65	0.44–0.65	0.44–0.65

5.2 Product Analysis
5.2.1 An analysis shall be made by the manufacturer of one billet or one tube from each heat. The chemical composition thus determined, shall conform to the requirements given in Table 1.
5.2.2 If the original test for product analysis fails, retests of two additional billets or tubes shall be made. Both retests for the elements in question shall meet the requirements of the specification; otherwise all remaining material in the heat or lot (See 7.1) shall be rejected or, at the option ofthe producer, each billet or tube may be individually tested for acceptance. Billets or tubes that do not meet the requirements of the specification shall be rejected.
 

6. Mechanical Properties
6.1 Tensile Requirements
6.1.1 The material shall conform to the requirements given in Table 2.
 
TABLE 2 Tensile Requirements

	Grade T1	Grade T1a	Grade T1b
Tensile strength, min, ksi [MPa]	55 [380]	53 [365]	60 [415]
Yield strength, min, ksi [MPa]	30 [205]	28 [195]	32 [220]
Elongation in 2 in. or 50 mm, min, %	30	30	30
For longitudinal strip tests a deduction shall be made for each 1 ⁄ 32 -in. [0.8-mm] decrease in wall thickness below 5 ⁄ 1 6 in. [8 mm] from the basic minimum elongation of the following percentage	1.50 A	1.50 A	1.50 A
When standard round 2-in. or 50-mm gage length or smaller proportionally sized specimen with the gage length equal to 4D (four times the diameter) is used	22	22	22

A Table 3 gives the computed minimum values.
 
6.1.2 Table 3 gives the computed minimum elongation values for each 1 ⁄ 32 -in. [0.8-mm] decrease in wall thickness.Where the wall thickness lies between two values shown above, the minimum elongation value shall be determined by the following equation: where:
E = elongation in 2 in. [50 mm], %, and,
t = actual thickness of specimen, in. [mm].
 
TABLE 3 Computed Minimum Values

Wall Thickness		Elongation in 2 in. or 50 mm, min, % A
in.	mm
5 ⁄ 1 6 (0.312)	8	30
9 ⁄ 32 (0.281)	7.2	29
1 ⁄ 4 (0.250)	6.4	27
7 ⁄ 32 (0.219)	5.6	26
3 ⁄ 1 6 (0.188)	4.8	24
5 ⁄ 32 (0.156)	4	22
1 ⁄ 8 (0.125)	3.2	21
3 ⁄ 32 (0.094)	2.4	20
1 ⁄ 1 6 (0.062)	1.6	18

A Calculated elongation requirements shall be rounded to the nearest whole
number.
 
6.2 Hardness Requirements—The tubes shall have a hardness not exceeding the values given in Table 4.
 

	Brinell Hardness Number (Tubes 0.200 in. [5.1 mm] and over in Wall Thickness), HBW	Rockwell Hardness Number (Tubes less than 0.200 in. [5.1 mm] in Wall Thickness), HRB
Grade T 1	146	80
Grade T 1a	153	81
Grade T 1b	137	77

 
6.3 Number ofTests
6.3.1 Tension Test—One tension test shall be made on a specimen for lots of not more than 50 tubes. Tension tests shall be made on specimens from two tubes for lots of more than 50 tubes (See 7.2)
6.3.2 Flattening Test—One flattening test shall be made on specimens from each end ofone finished tube, not the one used for the flaring test, from each lot (See 7.1)
6.3.3 Flaring Test—One flaring test shall be made on specimens from each end ofone finished tube, not the one used for the flattening test, from each lot (See 7.1)
6.3.4 Hardness Test—Brinell or Rockwell hardness tests shall be made on specimens from two tubes from each lot (See7.2)

 
7. Sampling
7.1 Flattening, Flaring, and Product Analysis—For flattening, flaring, and product analysis requirements, the term lot applies to all tubes prior to cutting of the same nominal size and wall thickness that are produced from the same heat of steel. When final heat treatment is in a batch-type furnace, a lot shall include only those tubes of the same size and from the same heat that are heat treated in the same furnace charge.When the final heat treatment is in a continuous furnace, the
number of tubes of the same size and from the same heat in a lot shall be determined from the size ofthe tubes given in Table 5.
 
TABLE 5 Number of Tubes in a Lot Heat Treated by the Continuous Process

Size of Tube	Size of Lot
2 in. [50.8 mm] and over in outside diameter and 0.200 in. [5.1 mm] and over in wall thickness	not more than 50 tubes
2 in. [50.8 mm] and over in outside diameter and under 0.200 in. [5.1 mm] in wall thickness	not more than 75 tubes
Less than 2 in. [50.8 mm] but over 1 in. [25.4 mm] in outside diameter	not more than 75 tubes
1 in. [25.4 mm] or less in outside diameter	not more than 125 tubes

7.2 Tension and Hardness Tests—For tension and hardness tests, the term lot applies to all tubes prior to cutting, of the same nominal diameter and wall thickness that are produced from the same heat of steel. When final heat treatment is in a batch-type furnace, a lot shall include only those tubes of the same size and the same heat that are heat treated in the same furnace charge. When the final heat treatment is in a continuous furnace, a lot shall include all tubes of the same size and heat,heat treated in the same furnace at the same temperature, time at heat, and furnace speed.
 

8. Forming Operations
8.1 Tubes when inserted in the boiler shall stand expanding and beading without showing cracks or flaws. Superheater tubes when properly manipulated shall stand all forging,welding, and bending operations necessary for application without developing defects.

9. Product Marking
9.1 In addition to the marking prescribed in Specification A1016/A1016M, the marking shall include whether the tube is hot-finished or cold-finished.
 
10. Keywords
10.1 boiler tubes; carbon-molybdenum; seamless steel tube; steel tube; superheater tubes