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ASTM A688 Tube

ASTM A688 tube

What is ASTM A688?

ASTM A688 Tube defines a type of welded austenitic stainless steel tubing mainly employed for high temperature service applications including nuclear power and other industries. This specification consists of seamless and welded tubes produced from grades including 304, 316, 347 and others showing high corrosion resistance and strength.

The tubes are normally used where high pressure, high temperature and radiation effects are expected. ASTM A688 tubes have close tolerance limits that in addition to the mechanical tests, also undergo hydrostatic and dimensional tests to meet the needed conditions for use in various environments.

Which is the Most Common Method to Manufacture ASTM A688 Seamless Tube?

The extrusion process is the most common method for manufacturing ASTM A688 seamless tube. This is basically a comprehensive deformation process, wherein the metal is squeezed through an orifice or die opening so as to obtain a reduction in the diameter. This leads to an increase in the metal block. Through the procedure, one can get the desired cross-section on their seamless ASTM A688 TP316LN Boiler Tubes.

Table of Contents


Specifications of A688 seamless tube

ASME SA 688 Seamless Feedwater Heater Tubes Manufacturer in India

Specifications of ASME SA 688 Tube

ASTM A688 tube specification

 

 

 

ASTM A688 seamless tube outer diameter

ASTM A688 seamless tube outer diameter

  • 12.7 to 102 MM
ASTM A688 welded tube wall thickness

ASTM A688 welded tube wall thickness

  • 0.5 to 5 MM

 

 

A688 stainless steel feedwater heater tubes length

A688 stainless steel feedwater heater tubes length

  • upto 30 meters Straight lenghts
ASTM A688M coil tubing welding method

ASTM A688M coil tubing welding method

  • Plasma or Laser

 

 

A688 Class B tubing bending radius

A688 Class B tubing bending radius

  • max 1500 mm
A688 Class F heat exchanger tubes manufacturing method

A688 Class F heat exchanger tubes manufacturing method

  • Cold drawing
  • Cold worked

 

 

A688 Class K bright annealed tubes testing

A688 Class K bright annealed tubes testing

  • Flare test
  • Flange test
  • Dimensional
  • Hydrostatic test
  • Pneumatic test
Applications of ASTM A688M coil tubing

Applications of ASTM A688M coil tubing

  • Boiler
  • Heat exchanger
  • Cooling
  • Condenser
  • Heater

 

 

ASTM A688 TP316LN boiler tubes schedule

ASTM A688 TP316LN boiler tubes schedule

  • SCH. 5
  • SCH. 1020
  • SCH. 30
  • SCH. 40
  • SCH. 60
  • SCH. 80
  • SCH. 100
  • SCH. 120
  • SCH. 140
  • SCH. 160, XXS
ASTM A688 Class D condenser tube grades

ASTM A688 Class D condenser tube grades

  • 304
  • 304L
  • 316
  • 316L

Stock and Supply A688 Welded Feedwater Heater Tubes in Custom Shapes at Best Price

ASTM A688 Tube Types

ASTM A688 welded tube

ASTM A688 welded tube

A688 stainless steel feedwater heater tubes

A688 stainless steel feedwater heater tubes

A688 u-tubes

A688 u-tubes

ASTM A688 TP316LN boiler tubes

ASTM A688 TP316LN boiler tubes

ASTM A688 seamless tube

ASTM A688 seamless tube

ASTM A688m coil tubing

ASTM A688M coil tubing

ASTM A688 TP316N heater tubes

ASTM A688 TP316N heater tubes

ASTM A688 Class D condenser tube

ASTM A688 Class D condenser tube

A688 Class K bright annealed tubes

A688 Class K bright annealed tubes

A688 Class F heat exchanger tubes

A688 Class F heat exchanger tubes

ASTM A688 Class C cold drawn seamless tube

ASTM A688 Class C cold drawn seamless tube

A688 Class B anneled tubing

A688 Class B anneled tubing

A688 Stainless Steel Feedwater Heater Tubes Equivalent

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

 

Element Classes G to N and GH to NH Classes A to F and AH to FH
Manganese % maximum - 1.35
Phosphorous % maximum 0.040 0.050
Sulfur % maximum 0.040 0.050

ASTM A688M Tubing Permissible Variations in Dimensions

ASTM A688M Tubing Permissible Variations in Dimensions

The ASTM A688 Tubes providers listed above have ex-stock and have already supplied to several countries, including Jordan, Iran, South Africa, and Libya.

Tolerance of A688 Welded Feedwater Heater Tubes

Acceptable Description Tolerances
Leg Lengths Different ≤ 3.2 Milimeter
Deviation From Plane Of Bend ≤ 1.5 Milimeter
Leg Lengths Tolerance L L ≤ 6 M 6 > L ≤ 9 M L > 9 M +3.2 Milimeter – 0 +4 Milimeter – 0 +4.8 Milimeter – 0
Leg Spacing (Measured At Tangency Point) ± 1.5 Milimeter
Radius R ± 1.5 Milimeter
Wall Thickness In Bent Portion Shall Not Be Less Than The Value Determined By The below Equation: Tf = (4R X T) / (4R + D) Where : Tf = Wall Thickness After Bending T = minimum Wall Thickness Before Bending R = Centerline Bend Radius D = No minimal Outside Tube Dia
Ovality In The Bent Portion (Also Called Flattening) ± 10 % This Can Be Described As Follow. (D maximum – D) / D < 10% (D – D minimum) / D < 10% “Neither The Major Nor minimum or Dia Of The Tube Shall Deviate From The No minimal Dia Prior To Bending By More Than 10%”
Squareness Of Ends D ≤ 15.9 Milimeter 15.9 > D ≤ 25.4 D ≥ 25.4 ≤ 38.1 0.25 Milimeter 0.4 Milimeter 0.4 Milimeter

Supplier Of SA 688 Austenitic Stainless Steel Feedwater Heater Tubes in Custom Range Of Sizes

ASTM A688 Seamless Tube Dimensions

Group PermisibleVariations

in Cut Length, in[milimeter]Over Under

Size, OD, in(milimeter) Permissible Variations in OD, in.[milimeter] Permissible Variations in WT, %
ASTM A688 welded tube 5 3/16[5] 0 5 1/2 - 5 1/2(139.7 to 230.2 excl ±0.030[0.76] ±10
ASTM A688 stainless steel welded tube 2 1/8[3] 0 1/2 - 1 1/2(12.7 to 38.1 excl ±0.005[0.13] ±10
ASTM A688 SS welded tube 1 1/8[3] 0 Up to 1/2(12.7), excl ±0.005[0.13] ±15
A688 stainless steel welded tube 4 3/16[5] 0 3 1/2 - 5 1/2(88.9 to 139.7 excl ±0.015[0.38] ±10
ASTM A688 welded tube 3 3/16[5] 0 1 1/2 - 3 1/2(38.1 to 88.9 excl ±0.010[0.25] ±10

Chemical Composition of ASME SA 688 Seamless Feedwater Heater Tubes

304 Stainless Steel

C 0.08%

Mn 2.00%

Ni 8.00 - 11.00%

Cr 18.00 – 20.00%

P 0.040%

S 0.030%

Si 0.75%

316 Stainless Steel

C 0.08%

Mn 2.00%

Ni 10.00 - 14.00%

Cr 16.00 – 18.00%

P 0.040%

S 0.030%

Si 0.75%

ASTM A688 Mechanical Properties

Class Size, inches Yield, min ksi Tensile, min ksi RA, % min Elong, % min in 2” Hardness, HBN
A Up to 20 - 47 - - 183 max
B Up to 20 30 60 36 24 120-174
C Up to 12 33 66 36 23 137-183
12 to 20 33 66 34 22 137-183
D Up to 8 37.5 75 40 24 149-207
8 to 12 37.5 75 35 22 149-207
12 to 20 37.5 75 19 20 149-207
Over 20 37.5 75 30 19 149-207
E Up to 8 44 85 40 25 174-217
8 to 12 44 85 37 23 174-217
12 to 20 43 83 35 22 174-217
F Up to 4 55 90 39 20 187-235
4 to 7 50 85 39 20 174-217
7 to 10 50 85 37 19 174-217
10 to 20 48 82 36 19 174-217
G Up to 12 50 80 40 24 163-207
12 to 20 50 80 38 22 163-207
H Up to 7 60 90 44 22 187-235
7 to 10 58 90 42 21 187-235
10 to 20 58 90 40 18 187-235
J Up to 7 70 95 50 20 197-255
7 to 10 65 90 50 20 187-235
10 to 20 65 90 48 18 207-255
K Up to 7 80 105 50 20 212-269
7 to 10 75 100 50 19 207-269
10 to 20 75 100 48 18 207-269
L Up to 4 105 125 50 16 255-321
4 to 7 95 115 45 16 235-302
7 to 10 85 110 45 16 223-293
10 to 20 85 110 40 14 223-293
M Up to 4 120 145 45 15 293-352
4 to 7 115 140 40 14 285-341
7 to 10 110 135 40 13 269-331
10 to 20 110 135 38 12 269-341
N Up to 4 140 170 40 13 331-401
4 to 7 135 165 35 12 331-401
7 to 10 130 160 35 11 321-388
10 to 20 130 160 35 11 321-402
Buy ASTM A688 Stainless Steel Tube for Tubular Feed Water Heaters with Various Heat Treatment

Heat Treatment of ASTM A688 Tube

Class Heat Treatment
A Untreated
B Annealed, or normalized, or normalized and tempered
C Annealed, or normalized, or normalized and tempered
D Annealed, or normalized, or normalized and tempered
E Normalized and tempered or double normalized and tempered
F Quenched and tempered, or normalized, quenched and tempered
G Annealed, or normalized, or normalized and tempered
H Normalized and tempered
J Normalized and tempered, or normalized, quenched and tempered
K Normalized, quenched and tempered
L Normalized, quenched and tempered
M Normalized, quenched and tempered
N Normalized, quenched and tempered
Offer ASTM A688 U Bend Tube Online Tested With Flattening and Hydrostatic Test

Testing of ASTM A688 Welded Tube

  • Tensile Strength
  • Reverse bending test
  • Flattening test
  • Flare test
  • Flange test
  • Dimensional
  • Hydrostatic Test
  • Pneumatic Test
  • Hardness
  • Eddy Current test
  • Intergranular Corrosion (option)


SA688 Welded Tube Manufacturing Process

  • Material Preparation
  • Tube Formation
  • Welding
  • Heat Treatment
  • Sizing
  • Cut to Length
  • Finishing
  • Testing

ASTM A688 Seamless versus Welded Tubes

Property Seamless Tubes Welded Tubes
Maximum Working Pressure Up to 5,000 psi Up to 3,000 psi
Yield Strength 205 to 415 MPa 170 – 380 MPa
Tensile Strength 70,000 to 100,000 psi 65,000 to 95,000 psi
Hardness 70 to 90 HRB 70 to 85 HRB
Elongation 40% to 50% 30% to 45%
Maximum Temperature 1,800°F to 2,200°F 1,700°F to 2,000°F
Corrosion Resistance it has Excellent Resistance it has Good Resistance
Surface Finish 10 to 50 µin 20 to 60 µin

ASTM A688 Tube Price List

Price List Price in USD Price in UAE Dirham
ASTM A688 Welded Tube Size: 6.35mm x 204mm x 0.25mm US $ 7.00 / foot UAE 25.70 / foot
ASTM A688 Seamless Tube Size: 6.35mm x 204mm x 0.25mm US $ 0.25 / inch UAE 0.92 / inch

ASME SA 688 Seamless Feedwater Heater Tubes HS Code

HS CODE
ASTM A688 SS Welded Tube 73064000

ASTM A688 Boiler Tubes Weight Chart

ID (mm) OD (mm) Wall Thickness (mm) Weight (kg/m)
12 15 1.5 0.56
8 10 1 0.32
25 30 2.5 1.42
10 12 1.0 0.38
32 38 3 1.87
16 20 2 0.90
56 63 3.5 3.00
21 25 2 1.13
90 100 5 6.12
44 50 3 2.35
138 150 6 10.93
68 76 4 3.85

ASTM A688 Tube Size Chart

Outer Diameter (OD) Inner Diameter (ID) Wall Thickness (WT) Inner Diameter (ID) Outer Diameter (OD) Wall Thickness (WT)
6 mm 4 mm 1 mm 0.157 in 0.236 in 0.039 in
125 mm 113 mm 6 mm 4.449 in 4.921 in 0.236 in
8 mm 6 mm 1 mm 0.236 in 0.315 in 0.039 in
76 mm 68 mm 4 mm 2.677 in 2.992 in 0.157 in
10 mm 8 mm 1.0 mm 0.315 in 0.394 in 0.039 in
63 mm 56 mm 3.5 mm 2.205 in 2.480 in 0.138 in
12 mm 10 mm 1.0 mm 0.394 in 0.472 in 0.039 in
150 mm 138 mm 6 mm 5.433 in 5.906 in 0.236 in
15 mm 12 mm 1.5 mm 0.472 in 0.591 in 0.059 in
38 mm 32 mm 3 mm 1.260 in 1.496 in 0.118 in
20 mm 16 mm 2 mm 0.629 in 0.787 in 0.079 in
100 mm 90 mm 5 mm 3.543 in 3.937 in 0.197 in
25 mm 21 mm 2 mm 0.827 in 0.984 in 0.079 in
200 mm 184 mm 8 mm 7.244 in 7.874 in 0.315 in
30 mm 25 mm 2.5 mm 0.984 in 1.181 in 0.098 in
250 mm 230 mm 10 mm 9.055 in 9.843 in 0.394 in
50 mm 44 mm 3 mm 1.732 in 1.969 in 0.118 in

Density and Melting point of SA 688 Austenitic Stainless Steel Condenser Tube

Property Value Value
Density 8.0 g/cm³ 8000kg/m³
Melting Point 1400 - 1450°C 2552 - 2642 °F

A688 Welded Tubing Pressure Rating

Outer Diameter (OD) Wall Thickness (WT) Pressure Rating at 1000°F psi Pressure Rating at 200°F psi Pressure Rating at 150°F psi
1 inch 0.065 inch 1,200 1,900 2,000
10 inch 0.250 inch 275 425 450
2 inch 0.095 inch 700 1,100 1,200
6 inch 0.190 inch 350 570 600
3 inch 0.120 inch 600 950 1,000
8 inch 0.250 inch 300 475 500
4 inch 0.140 inch 500 750 800

ASTM A688 Tube Shipping Time and Location

Changes in Cost
Extra 5 %
Delivery Location Shiping Time in Days
Norway 45
Bahamas  60
Uk 30
Panama 45
Spain  30
Netherland 30
Russia 20
Canada 45
Denmark 35
Trinidad And Tobago 60
France 28
Puerto Rica 45
Jamaica 50
Mexico 45
Costa Rica 45
Germany 21
Ukraine 60
Italy 28