ASTM A249 Welded Austenitic Steel Tubes

ASTM A249/A249M

Standard Specification for

Welded Austenitic Steel Boiler, Superheater, Heat-Exchanger, and Condenser Tubes

 

 

1. Scope*

1.1 This specification 2 covers nominal-wall-thickness welded tubes and heavily cold worked welded tubes made from the austenitic steels listed in Table 1, with various grades intended for such use as boiler, superheater, heat exchanger, or condenser tubes.
 

1.2 Grades TP304H, TP309H, TP309HCb, TP310H,TP310HCb, TP316H, TP321H, TP347H, and TP348H are modifications of Grades TP304, TP309S, TP309Cb, TP310S,TP310Cb, TP316, TP321, TP347, and TP348, and are intended for high-temperature service such as for superheaters and reheaters.
 

1.3 The tubing sizes and thicknesses usually furnished to this specification are 1 ⁄ 8 in. [3.2 mm] in inside diameter to 12 in. [304.8 mm] in outside diameter and 0.015 to 0.320 in. [0.4 to 8.1 mm], inclusive, in wall thickness. Tubing having other dimensions may be furnished, provided such tubes comply with all other requirements of this specification.
1.4 Mechanical property requirements do not apply to tubing smaller than 1 ⁄ 8 in. [3.2 mm] in inside diameter or 0.015 in. [0.4 mm] in thickness.

1.5 Optional supplementary requirements are provided and,when one or more of these are desired, each shall be so stated in the order.

1.6 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 of the 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.
 

1.7 The following safety hazards caveat pertains only to the test method described in the Supplementary Requirements of this specification. This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. A specific warning statement is given in Supplementary Requirement S7, Note S7.1.

 

 

2. Referenced Documents

2.1 ASTM Standards:

A 262 Practices for Detecting Susceptibility to Intergranular Attack in Austenitic Stainless Steels

A 480/A 480M Specification for General Requirements for Flat-Rolled Stainless and Heat-Resisting Steel Plate,Sheet, and Strip

A 1016/A 1016M Specification for General Requirements for Ferritic Alloy Steel, Austenitic Alloy Steel, and Stainless Steel Tubes

E 112 Test Methods for Determining Average Grain Size

E 213 Practice for Ultrasonic Examination of Metal Pipe and Tubing

E 273 Practice for Ultrasonic Examination of the Weld Zone of Welded Pipe and Tubing

E 527 Practice for Numbering Metals and Alloys in the Unified Numbering System (UNS)

2.2 ASME Boiler and Pressure Vessel Code:

Section VIII

2.3 Other Standard:

SAE J1086 Practice for Numbering Metals and Alloys (UNS)

 

 

3. Ordering Information

3.1 It is the responsibility of the purchaser to specify all requirements that are necessary for material ordered under this specification. Such requirements may include, but are not limited to, the following:

3.1.1 Quantity (feet, metres, or number of lengths),

3.1.2 Name of material welded tubes (WLD) or heavily cold worked tubes (HCW),

3.1.3 Grade (Table 1),

3.1.4 Size (outside diameter and nominal wall thickness),

3.1.5 Length (specific or random),

3.1.6 Optional requirements (13.6),

3.1.7 Test report required (see Certification Section of Specification A 1016/A 1016M),

3.1.8 Specification designation, and

3.1.9 Special requirements and any supplementary requirements selected.

 

 

 

4. General Requirements

4.1 Material furnished under this specification shall conform to the applicable requirements of the current edition of Specification A 1016/A 1016M, unless otherwise provided herein.

 

 

5. Manufacture

5.1 The welded (WLD) tubes shall be made from flat-rolled steel by an automatic welding process with no addition of filler metal.

5.1.1 Subsequent to welding and prior to final heat treatment, the tubes shall be cold worked either in both weld and base metal or in weld metal only. The method of cold working may be specified by the purchaser. When cold drawn, the purchaser may specify the minimum amount of reduction in cross-sectional area or wall thickness, or both.

5.1.2 Heavily cold worked (HCW) tubes shall be made by applying cold working of not less than 35 % reduction in both wall and weld to a welded tube prior to the final anneal. No filler metal shall be used in the making of the weld. Prior to cold working, the weld shall be 100 % radiographically inspected in accordance with the requirements of ASME Boiler and Pressure Vessel Code, Section VIII, Division 1, latest revision, Paragraph UW 51.

 

 

 

6. Heat Treatment

6.1 All material shall be furnished in the heat-treated condition in accordance with the requirements of Table 2.

6.2 A solution annealing temperature above 1950 °F [1065°C] may impair the resistance to intergranular corrosion after subsequent exposure to sensitizing conditions in TP309HCb,TP310HCb, TP321, TP321H, TP347, TP347H, TP348, and TP348H. When specified by the purchaser, a lower temperature stabilization or re-solution anneal shall be used subsequent to the initial high temperature solution anneal (see Supplementary Requirement S4).
 

TABLE 2 Heat Treatment Requirements

 

Grade	UNS Number	Solutioning Temperature, min or range	Quenching Method
All grades not individually listed below		1900 °F [1040 °C]	A
....	S30815	1920 °F [1050 °C]	B
TP309HCb	S30941	1900 °F [1040 °C]   C	B
TP310H	S31009	1900 °F [1040 °C]	B
TP310HCb	S31041	1900 °F [1040 °C]  C	B
...	S31254	2100 °F [1150 °C]	B
...	S31277	2050 °F [1120 °C]	B
TP316H	S31609	1900 °F [1040 °C]	B
...	S31727	1975 °F [1080 °C]– 2155 °F [1180 °C]	B
...	S32053	1975 °F [1080 °C]– 2155 °F [1180 °C]	B
TP321	S32100	1900 °F [1040 °C] C	B
TP321H	S32109	2000 °F [1100 °C] C	B
...	S32654	2100 °F [1150 °C]	B
...	S33228	2050 °F [1120 °C]	B
...	S34565	2050 °F [1120 °C]– 2140 °F [1170 °C]	B
TP347	S34700	1900 °F [1040 °C] C	B
TP347H	S34709	2000 °F [1100 °C] C	B
TP348	S34800	1900 °F [1040 °C] C	B
TP348H	S34809	2000 °F [1100 °C] C	B
...	S35045	2000 °F [1100 °C]	D
...	S38815	1950 °F [1065 °C]	B
...	N08367	2025 °F [1110 °C]	B
...	N08904	2000 °F [1100 °C]	B
...	N08926	2010 °F [1105 °C]	B

 

 

 

7. Chemical Composition

7.1 The heat analysis shall conform to the requirements as to chemical composition given in Table 1.

 
 

TABLE 1 Chemical Requirements, % 

 

Grade	UNS Designation	Composition, %
		Carbon	Manganese	Phosphorous	Sulfur	Silicon	Chromium	Nickel	Molybdenum	Nitrogen	Copper	Other
TP 201	S20100	0.15	5.5-7.5	0.060	0.030	1.00	16.0-18.0	3.5-5.5	...	0.25	...	...
TP 201LN	S20153	0.03	6.4-7.5	0.045	0.015	0.75	16.0-17.5	4.0–5.0	...	0.10–0.25	1.00	...
TP 202	S20200	0.15	7.5-10.0	0.060	0.030	1.00	17.0-19.0	4.0-6.0	...	0.25	...	...
TPXM-19	S20910	0.06	4.0-6.0	0.045	0.030	1.00	20.5-23.5	11.5-13.5	1.5-3.0	0.20-0.40	...	Cb 0.10–0.30 V 0.10–0.30
TPXM-29	S24000	0.08	11.5-14.5	0.060	0.030	1.00	17.0-19.0	2.3-3.7	...	0.20-0.40	...	...
TP304	S30400	0.08	2.00	0.045	0.030	1.00	18.0-20.0	8.0-11.0	...	...	...	...
TP304L	S30403	0.03	2.00	0.045	0.030	1.00	18.0-20.0	8.0-12.0	...	....	...	...
TP304H	S30409	0.04-0.10	2.00	0.045	0.030	1.00	18.0-20.0	8.0-11.0	...	....	...	...
....	S30415	0.04-0.06	0.80	0.045	0.030	1.0-2.0	18.0-19.0	9.0-10.0	...	0.12-0.18	...	Ce 0.03–0.08
TP304N	S30451	0.08	2.00	0.045	0.030	1.00	18.0-20.0	8.0-11.0	...	0.10-0.16	...	...
TP304LN	S30453	0.03	2.00	0.045	0.030	1.00	18.0-20.0	8.0-11.0	...	0.10-0.16	...	...
TP305	S30500	0.12	2.00	0.045	0.030	1.00	17.0-19.0	11.0-13.0	...	...	...	...
....	S30615	0.16-0.24	2.00	0.030	0.030	3.2-4.0	17.0-19.5	13.5-16.0	...	...	...	...
....	S30815	0.50-0.10	0.80	0.040	0.030	1.4-2.0	20.0-22.0	10.0-12.0	...	0.14-0.20	...	Ce 0.03–0.08
TP309S	S30908	0.08	2.00	0.045	0.030	1.00	22.0-24.0	12.0-15.0	...	...	...	...
TP309H	S30909	0.04-0.10	2.00	0.045	0.030	1.00	22.0-24.0	12.0-15.0	...	...	...	...
TP309Cb	S30940	0.08	2.00	0.045	0.030	1.00	22.0–24.0	12.0–16.0	..	...	...	Cb 10x C-1.10
TP309HCb	S30941	0.04-0.10	2.00	0.045	0.030	1.00	22.0–24.0	12.0–16.0	..	...	...	Cb 10x C-1.10
TP310S	S31008	0.08	2.00	0.045	0.030	1.00	24.0–26.0	19.0–22.0	..	...	...	..
TP310H	S31009	0.04-0.10	2.00	0.045	0.030	1.00	24.0–26.0	19.0–22.0	..	...	...	..
TP310Cb	S31040	0.08	2.00	0.045	0.030	1.00	14.0-26.0	18.0–22.0	..	...	...	Cb 10x C-1.10
TP310HCb	S31041	0.04-0.10	2.00	0.045	0.030	1.00	24.0–26.0	19.0–22.0	..	...	...	Cb 10x C-1.10
....	S31050	0.03	2.00	0.030	0.015	0.40	24.0–26.0	21.0–23.0	2.00–3.00	0.10–0.16		..
....	S31254	0.02	1.00	0.030	0.010	0.80	19.5-20.5	17.5–18.5	6.0–6.5	0.18–0.25	0.50–1.00	..
.....	S31277	0.02	3.00	0.030	0.010	0.50	20.5-23.0	26.0–28.0	6.5–8.0	0.30–0.40	0.50–1.50	..
TP316	S31600	0.08	2.00	0.045	0.030	1.00	16.0–18.0	10.0–14.0	2.00–3.00	...	...	..
TP316L	S31603	0.03	2.00	0.045	0.030	1.00	16.0–18.0	10.0–14.0	2.00–3.00	...	...	..
TP316H	S31609	0.04-0.10	2.00	0.045	0.030	1.00	16.0–18.0	10.0–14.0	2.00–3.00	...	...	..
TP316N	S31651	0.08	2.00	0.045	0.030	1.00	16.0–18.0	10.0–13.0	2.00–3.00	0.10–0.16	...	..
TP316LN	S31653	0.03	2.00	0.045	0.030	1.00	16.0–18.0	10.0–13.0	2.00–3.00	0.10–0.16	...	..
TP317	S31700	0.08	2.00	0.045	0.030	1.00	18.0-20.0	11.0–15.0	3.0-4.0	...	...	..
TP317L	S31703	0.03	2.00	0.045	0.030	1.00	18.0-20.0	11.0–15.0	3.0-4.0	...	...	..
....	S31725	0.03	2.00	0.045	0.030	1.00	18.0-20.0	13.5–17.5	4.0–5.0	0.20	...	..
.....	S31726	0.03	2.00	0.045	0.030	1.00	17.0-20.0	14.5–17.5	4.0–5.0	0.10–0.20	...	..
.....	S31727	0.03	1.00	0.030	0.030	1.00	17.5-19.0	14.5–16.5	3.8–4.5	0.15–0.21	2.8–4.0	..
.....	S32050	0.03	1.50	0.030	0.020	1.00	22.0-24.0	20.0–23.0	6.0–6.8	0.21–0.32	0.40	..
.....	S32053	0.03	1.00	0.030	0.010	1.00	22.0-24.0	24.0–26.0	5.0–6.0	0.17–0.22	...	..
TP321	S32100	0.08	2.00	0.045	0.030	1.00	17.0-19.0	9.0–12.0	..	0.10	...	Ti 5(C+N)- 0.70
TP321H	S32109	0.04-0.10	2.00	0.045	0.030	1.00	17.0-19.0	9.0–12.0	..	0.10	...	Ti 5(C+N)- 0.70
....	S32654	0.02	2.0-4.0	0.030	0.005	0.50	24.0-25.0	21.0–23.0	7.0–8.0	0.45–0.55	0.30–0.60	..
....	S33228	0.04-0.08	1.00	0.020	0.015	0.30	26.0-28.0	31.0–33.0	..	..	...	Cb 0.60–1.00 Ce 0.05–0.10 Al0.025
.....	S34565	0.03	5.0-7.0	0.030	0.010	1.00	23.0-25.0	16.0–18.0	4.0–5.0	0.40–0.60	...	Cb 0.10
TP347	S34700	0.08	2.00	0.045	0.030	1.00	17.0-19.0	9.0–12.0	..	...	...	Cb 8xC- 1.10
TP347H	S34709	0.04-0.10	2.00	0.045	0.030	1.00	17.0-19.0	9.0–12.0	..	...	...	Cb 10xC- 1.10
TP348	S34800	0.08	2.00	0.045	0.030	1.00	17.0-19.0	9.0–12.0	..	...	...	(Cb+Ta) 10xC-1.10 Ta 0.10 Co 0.20
TP348H	S34809	0.04-0.10	2.00	0.045	0.030	1.00	17.0-19.0	9.0–12.0	..	...	...	(Cb+Ta) 8xC-1.10 Ta 0.10 Co 0.20
....	S35045	0.04-0.16	1.50	0.045	0.015	1.00	25.0–29.0	32.0–37.0	..	...	0.75	Al 0.15–0.60 Ti 0.15–0.60
TPXM-15	S38100	0.08	2.00	0.030	0.030	1.5–2.5	17.0–19.0	17.5–18.5	..	...	...	...
....	S38815	0.03	2.00	0.040	0.020	5.5–6.5	13.0–15.0	15.0–17.0	0.75–1.50	...	0.75–1.50	Al 0.30 max
....	N08367	0.03	2.00	0.040	0.030	1.00	20.0–22.0	23.5–25.5	6.0–7.0	0.18–0.25	0.75	...
....	N08926	0.02	2.00	0.030	0.010	0.50	19.0–21.0	24.0–26.0	6.0–7.0	0.15–0.25	0.50–1.50	...
....	N08904	0.02	2.00	0.040	0.030	1.00	19.0–23.0	23.0–28.0	4.0-5.0	0.10	1.00–2.00	...

 

 

8. Product Analysis

8.1 An analysis of either one length of flat-rolled stock or one tube shall be made for each heat. The chemical composition thus determined shall conform to the requirements given in Section 7.

8.2 A product analysis tolerance of Table A1.1 in Specification A 480/A 480M shall apply. The product analysis tolerance is not applicable to the carbon content for material with a specified maximum carbon of 0.04 % or less.

8.3 If the original test for product analysis fails, retests of two additional lengths of flat-rolled stock 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 Note 1) shall be rejected or, at the option of the producer, each length of flat-rolled stock or tube may be individually tested for acceptance. Lengths of flat-rolled stock or tubes that do not meet the requirements of the specification shall be rejected.

 

NOTE 1—For flattening and flange requirements, the term lot applies to all tubes prior to cutting of the same nominal size and wall thickness which 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 which 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 of the tubes as prescribed in Table 3.

 

NOTE 2—For tension and hardness test requirements, the term lot applies to all tubes prior to cutting, of the same nominal diameter and wall thickness which 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 which 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, annealed in the same furnace at the same temperature, time at heat, and furnace speed.

 
 

 

 

9. Tensile Requirements

9.1 The material shall conform to the tensile properties prescribed in Table 4.
 

Grade	UNS Designation	Tensile Strength, min, ksi [MPa]	Yield Strength, min, ksi [MPa]	Elongation in 2 in. or 50 mm,min, %	Rockwell Hardness Number,max
TP 201	S20100	95 [655]	38 [260]	35	B95
TP 201LN	S20153	95 [655]	45 [310]	45	B100
TP 202	S20200	90 [620]	38 [260]	35	B95
TPXM-19	S20910	100 [690]	55 [380]	35	C25
TPXM-29	S24000	100 [690]	55 [380]	35	B100
TP304	S30400	75 [515]	30 [205]	35	B90
TP304L	S30403	70 [485]	25 [170]	35	B90
TP304H	S30409	75 [515]	30 [205]	35	B90
....	S30415	87 [600]	42 [290]	35	B96
TP304N	S30451	80 [550]	35 [240]	35	B90
TP304LN	S30453	75 [515]	30 [205]	35	B90
TP305	S30500	75 [515]	30 [205]	35	B90
....	S30615	90 [620]	40 [275]	35	B95
....	S30815	87 [600]	45 [310]	35	B95
TP309S	S30908	75 [515]	30 [205]	35	B90
TP309H	S30909	75 [515]	30 [205]	35	B90
TP309Cb	S30940	75 [515]	30 [205]	35	B90
TP309HCb	S30941	75 [515]	30 [205]	35	B90
TP310S	S31008	75 [515]	30 [205]	35	B90
TP310H	S31009	75 [515]	30 [205]	35	B90
TP310Cb	S31040	75 [515]	30 [205]	35	B90
TP310HCb	S31041	75 [515]	30 [205]	35	B90
....	S31050
	t ≤ 0.25 in.	84 [580]	39 [270]	25	B95
	t > 0.25 in.	78 [540]	37 [255]	25	B95
....	S31254
	t ≤ 0.187 in. [5.00 mm]	98 [675]	45 [310]	35	B100
	t > 0.187 in. [5.00 mm]	95 [655]	45 [300]	35	B100
.....	S31277	112 [770]	52 [360]	40	B100
TP316	S31600	75 [515]	30 [205]	35	B90
TP316L	S31603	70 [485]	25 [170]	35	B90
TP316H	S31609	75 [515]	30 [205]	35	B90
TP316N	S31651	80 [550]	35 [240]	35	B90
TP316LN	S31653	75 [515]	30 [205]	35	B90
TP317	S31700	75 [515]	30 [205]	35	B90
TP317L	S31703	75 [515]	30 [205]	35	B90
....	S31725	75 [515]	30 [205]	35	B90
.....	S31726	80 [550]	35 [240]	35	B90
.....	S31727	80 [550]	36 [245]	35	B96
.....	S32050	98 [675]	48 [330]	40
.....	S32053	93 [640]	43 [295]	40	B96
TP321	S32100	75 [515]	30 [205]	35	B90
TP321H	S32109	75 [515]	30 [205]	35	B90
....	S32654	109 [750]	62 [430]	35	B100
....	S33228	73 [500]	27 [185]	30	B90
.....	S34565	115 [795]	60 [415]	35	B100
TP347	S34700	75 [515]	30 [205]	35	B90
TP347H	S34709	75 [515]	30 [205]	35	B90
TP348	S34800	75 [515]	30 [205]	35	B90
TP348H	S34809	75 [515]	30 [205]	35	B90
....	S35045	70 [485]	25 [170]	35	B90
TPXM-15	S38100	75 [515]	30 [205]	35	B90
....	S38815	78 [540]	37 [255]	30	B100
....	N08367
	t ≤  0.187	100 [690]	45 [310]	30	100
	t > 0.187	95 [655]	45 [310]	30	100
....	N08926	71 [490]	31 [215]	35	B90
....	N08904	94 [650]	43 [295]	35	B100

 

10. Hardness Requirements

10.1 The tubes shall have a Rockwell hardness number not exceeding the values specified in Table 4.

 
 

 

11. Reverse-Bend Test Requirement

11.1 A section 4 in. [100 mm] minimum in length shall be split longitudinally 90° on each side of the weld. The sample shall then be opened and bent around a mandrel with a maximum thickness of four times the wall thickness, with the mandrel parallel to the weld and against the original outside surface of the tube. The weld shall be at the point of maximum bend. There shall be no evidence of cracks, or of overlaps resulting from the reduction in thickness of the weld areas by cold working. When the geometry or size of the tubing make it difficult to test the sample as a single piece, the sample may be sectioned into smaller pieces provided a minimum of 4 in. of weld is subjected to reverse bending.

NOTE 3—The reverse bend test is not applicable when the specified wall is 10 % or more of the specified outside diameter, or the wall thickness is 0.134 in. [3.4 mm] or greater, or the outside diameter size is less than 0.375 in. [9.5 mm]. Under these conditions the reverse flattening test of Specification A 1016/A 1016M shall apply.

 


 

12. Grain Size Requirement

12.1 The grain size of Grades TP309H, TP309HCb,TP310H and TP310HCb, as determined in accordance with Test Methods E 112, shall be No. 6 or coarser.

12.2 The grain size of Grades TP304H, TP316H, TP321H,TP347H and TP348H, as determined in accordance with Test Methods E 112, shall be No. 7 or coarser.


 

13. Mechanical Tests and Grain Size Determinations Required

13.1 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 Note 2).

13.2 Flattening Test—One flattening test shall be made on specimens from each end of one finished tube, not the one used for the flange test, from each lot (See Note 1).

 

13.3 Flange Test—One flange test shall be made on specimens from each end of one finished tube, not the one used for the flattening test, from each lot (See Note 1).

13.4 Reverse-Bend Test—One reverse-bend test shall be made on a specimen from each 1500 ft [450 m] of finished tubing.

13.5 Hardness Test—Brinell or Rockwell hardness tests shall be made on specimens from two tubes from each lot (See Note 2).

13.6 Hydrostatic or Nondestructive Electric Test—Each tube shall be subjected to either the hydrostatic or the nondestructive electric test. The purchaser may specify which test is to be used.

13.7 Grain Size—Grain size determinations on grades TP309H, TP309HCb, TP310H and TP310HCb shall be made on the same number of tubes as prescribed for the flattening test.

13.8 Heavily cold worked tubes (HCW) shall be capable of passing the weld decay test listed in Supplementary S7 with a weld metal to base metal loss ratio of 0.90 to 1.10. The test is not required unless S7 is specified in the purchase order.

 

 
 

 

14. Permissible Variations in Dimensions

14.1 Dimensional tolerances other than wall thickness tolerances shall be in accordance with Specification A 1016/A 1016M. Wall thickness tolerances shall be 610 % of nominal wall for all tubing sizes.

14.2 The wall thickness of the weld shall not exceed the wall thickness measured 90° from the weld by more than 6 % of the specified wall thickness or 0.004 in. [0.1 mm], whichever is greater.

14.2.1 Requirements of 14.2 are not applicable when any of the following apply:

14.2.1.1 When the specified wall thickness exceeds 12 % of the specified outside diameter;

14.2.1.2 When the specified wall thickness exceeds 0.165 in. [4.2 mm];

14.2.1.3 When the specified OD exceeds 3 in. [76.2 mm]; or

14.2.1.4 When the specified minimum yield strength given in Table 4 for the specified grade is 35 ksi [240 MPa] or greater.

 

 

 

15. Workmanship, Finish, and Appearance

15.1 Finished tubes shall have smooth ends free of burrs and shall not deviate from straightness by more than 0.030 in. [0.8 mm] in 3 ft (900 mm] of length.

 

 

16. Surface Condition

16.1 The tubes, after final heat treatment, shall be chemically descaled or pickled free of scale. When bright annealing is used, pickling or chemical descaling is not necessary.

 
 

 

17. Forming Operations

17.1 Tubes when inserted in the boiler shall stand expanding and beading without showing cracks or flaws. All tubes, when properly manipulated, shall be able to stand expanding and beading without showing cracks and flaws, and also shall stand all forging, welding, and bending operations necessary for application without developing defects.

 
 

 

18. Product Marking

18.1 In addition to the marking prescribed in Specification A 1016/A 1016M, the marking for Grades TP304H, TP309H,TP309HCb, TP310H, TP310HCb, TP316H, TP321H, TP347H,and TP348H shall also include the heat number and the heat-treatment lot identification.

 

 
 

19. Keywords

19.1 austenitic stainless steel; boiler tubes; condenser tube; heat exchanger tube; high temperature applications; steel tube;superheater tubes; temperature service applications, high;welded steel tube and heavily cold worked (HCW) tubes