ASTM A688 Stainless Steel Feedwater Heater Tube




Welded Austenitic Stainless Steel Tube for Tubular Feed Water Heaters

Welded Austenitic Stainless Steel Feedwarter Heater Tube

ASTM A688 specification covers welded austenitic stainless steel feedwater heater tubes including those bent, if specified, into the form of U-tubes for application in tubular feed-water heaters. Welded feedwater heater tube sizes covered shall be 5 ⁄8 to 1 in. [15.9 to 25.4 mm] inclusive outside diameter, and average or minimum wall thicknesses of 0.028 in. [0.7 mm] and heavier.ASTM A688 stainless steel welded feedwater heater tube shall be made from flat-rolled steel by an automatic welding process with no addition of filler metal. We have most reputed name as a ASTM A688 316 welded stainless steel feedwater heater tube supplier.ASTM A688 welded Square and rectangular tube shall be marked with the heat  number. ASTM A688 304 welded tube is commonly shipped without protective coating. If special protection is needed, details shall be specified in the order. ASTM A688 welded rectangular tube yield strength corresponding to a permanent offset of 0.2 % of the gage length of the specimen or to a total extension of 0.5 % of the gage length under load shall be determined. Our offered ASTM A688 ss welded tubes primarily consist of the austenitic grades of stainless steel including 304, 304, 316, 316L, 316Ti with annealed and pickled, bright annealed mill finish, polished finish.

ASTM A688 SS Welded Tube Specifications

Specifications ASTM A688/ ASME SA688
Grades ASTM A688( MT304/304L, MT316/316L )
O.D. 12.7 – 102 MM
Wall Thickness 0.5 – 5 MM
Length Straight Lenghts upto 30 meters
Schedule SCH. 5, 10, 20, 30, 40, 60, 80, 100, 120, 140, 160, XXS.
Welding Method  TIG or TIG + Plasma or Laser
Finish 2B MIll Finish , No.4 finish, BA Finish, 400 Grit Finish, 550 Grit Finish, 600 Grit Finish
Types Round, Square, Rectangle, Coil, "U" Shape, Hydraulic & Honed Tubes
Products ASTM A688 304 Stainless Steel Polished Tubes, SS304L Polished Tubes, SS201 No.4 Finish Tube, SS316L Polished Tubes, ASTM A688 316L Tubing, ASTM A688 304L Heat Exchanger Tubes, ASTM A688 316L Welded Polished Tubes, ASTM A688 304 Stainless Steel Square Tube, ASTM A688 condenser tubes,ASTM A688 Square Tube
     

ASTM A688 Equivalent

GRADE UNS NO DIN/WERKSTOFF
ASTM A688 304 S30400 1.4301
ASTM A688 304H S30409
ASTM A688 304L S30403 1.4306
ASTM A688 310S S31008 1.4845
ASTM A688 316S S31600 1.4436
ASTM A688 316H S31609
ASTM A688 316 TI S31635 1.4571
ASTM A688 316L (2.5 MIN MOLY) S31603 1.4435
ASTM A688 316L S31603 1.4404
ASTM A688 317L S31703 1.4438
ASTM A688 321 S32100 1.4541
ASTM A688 321H S32109
ASTM A688 347 S34700 1.4550

Dimensions of ASTM A688 Welded Feedwater Heater Tubes

OD Size, in. (mm)

OD, ±in.

mm

ID, ±in.

mm

Up to 3⁄32 (2.4), excl

0.001

0.03

0.001

0.03

3⁄32 to 3⁄16 (2.4 to 4.8), excl

0.0015

0.038

0.0015

0.038

3⁄16 to 1⁄2 (4.8 to 12.7), excl

0.003

0.08

0.005

0.13

1⁄2 to 1 (12.7 to 25.4), excl

0.004

0.10

0.006

0.15

1 to 11⁄2 (25.4 to   38.1),excl

0.005

0.13

0.007

0.18

1 1⁄2 to 2 (38.1 to 50.8),excl

0.006

0.15

0.008

0.20

2 to 2 1⁄2 (50.8 to 63.5),excl

0.007

0.18

0.010

0.25

2 1⁄2 to 3 1⁄2 (63.5 to 88.9),excl

0.010

0.25

0.014

0.36

 

 

 

 

 

 

3 1⁄2 to 5 (88.9 to 127.0),incl

0.015

0.38

0.020

0.51

Over 5 to 16 (127.0 to 406.4), incl

0.00125 in./in. or mm/mm of cir-cumference

0.0013 in./in. or mm/mm of cir-cumference

 

Chemical Composition Of ASTM A688

 

Grade

TP 304 TP 304L TP 304LN TP 316 TP 316L

TP 316LN

TP XM-29

TP 304N TP 316N

. . .

. . .

. . .

. . .

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Element

UNS

S30400

S30403

S30453

S31600 S31603

S31653

S24000

S30451

S31651

N08367

N08926

S31254

S32654

DesignationA….

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Composition, %

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Carbon, max

 

0.08

0.035

0.035

0.08

0.035

0.035

0.060

0.08

0.08

0.030

0.020

0.020

0.020

Manganese, maxB

 

2.00

2.00

2.00

2.00

2.00

2.00

11.50–

2.00

2.00

2.00

2.00

1.00

2.0–4.0

 

 

 

 

 

 

 

 

14.50

 

 

 

 

 

 

Phosphorus, max

 

0.040

0.040

0.040

0.040

0.040

0.040

0.060

0.040

0.040

0.040

0.03

0.030

0.030

Sulfur, max

 

0.030

0.030

0.030

0.030

0.030

0.030

0.030

0.030

0.030

0.030

0.01

0.010

0.005

Silicon, max

 

0.75

0.75

0.75

0.75

0.75

0.75

1.00

0.75

0.75

1.00

0.5

0.80

0.50

Nickel

 

8.00–

8.00–

8.00–

10.00–

10.00–

10.00–

2.25–

8.00–

10.00–

23.50–

24.00–

17.5–

21.0–

 

 

11.00 13.00

13.00

14.00 15.00

15.00

3.75

11.0 14.00

25.50

26.00

18.5

23.0

Chromium

 

18.00–

18.00–

18.00–

16.00–

16.00–

16.00–

17.00–

18.0–

16.0–

20.00–

19.00–

19.5–

24.0–

 

 

20.00 20.00

20.00

18.00 18.00

18.00

19.00

20.0 18.0

22.00

21.00

20.5

25.0

Molybdenum

 

2.00–

2.00–

2.00–

2.00–

6.00–

6.0–

6.0–

7.0–

 

 

 

 

 

3.00 3.00

3.00

 

 

3.00

7.00

7.0

6.5

8.0

NitrogenC

 

0.10–

0.10–

0.20–

0.10–

0.10–

0.18–

0.15–

0.18–

0.45–

 

 

 

 

0.16

 

 

0.16

0.40

0.16 0.16

0.25

0.25

0.22

0.55

Copper

 

. . .

. . .

. . .

. . .

. . .

. . .

. . .

. . .

. . .

0.75 max

0.5–1.5

0.50–1.00

0.30–0.60

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

ASTM A688 Mechanical Properties

Grade and UNS Tensile strength 
min ksi [Mpa]
Yield strength 
min ksi [Mpa]
Elongation 
in 2in or 50mm min %
304, 316
S30400, S31600
75 [515] 30 [205] 35
304L, 316L
S30403, S31603
70 [485] 25 [175] 35
XM-29
S24000
100 [690] 55 [380] 35
304N, 316N
S30451, S31651
80 [550] 35 [240] 20
304LN, 316LN
S30453, S31653
75 [515] 30 [205] 35
N08367  t≤0.187 100 [690] 45 [310] 30
N08367  t>0.187 95 [655] 45 [310] 30
N08926 94 [650] 45 [310] 35
S31254   t≤0.187 100 [690] 45 [310] 35
S21254   t>0.187 95 [655] 45 [310] 35
S32654 120 [825] 65 [450] 40

Permissible Variations in ASTM A688 SS Welded Tube Dimensions

Group

Size, 
Outside Diameter, 
in(mm)

Permissible 
Variations in 
Outside 
Diameter, 
in.[mm]

Permissible 
Variations

 in WT, %

PermisibleVariations 

in Cut Length, 
in[mm]
Over Under

ASTM A688 stainless steel welded tube 1

Up to 1/2(12.7), excl

±0.005[0.13]

±15

1/8[3]

0

ASTM A688 stainless steel welded tube 2

1/2 to 1 1/2(12.7 to 38.1 excl

±0.005[0.13]

±10

1/8[3]

0

ASTM A688 stainless steel welded tube 3

1 1/2 to 3 1/2(38.1 to 88.9 excl

±0.010[0.25]

±10

3/16[5]

0

ASTM A688 stainless steel welded tube 4

3 1/2 to 5 1/2(88.9 to 139.7 excl

±0.015[0.38]

±10

3/16[5]

0

ASTM A688 stainless steel welded tube 5

5 1/2 to 5 1/2(139.7 to 230.2 excl

±0.030[0.76]

±10

3/16[5]

0

Top