Stainless steel flange materials: ASTM A182 F304, F309, F310, F316, F347 chemical composition, pressure rating, and mechanical properties.

 

ASTM A182 CHEMICAL COMPOSITION

The chemical composition of common stainless steel flange material grades. The key elements that differentiate the materials are the Nickel (Ni), Chrome (Cr), and Molybdenum content (Mo). The price for these metals fluctuates daily on the London Metal Exchange (Nickel, Moly) and on the ferroalloy market (ferrochrome).

ASTM A182 Stainless Steel Flanges Materials Composition, %
ASTM A182 GRADE C Mn P S Si Ni Cr Mo Nb Ti Others
F304(1) 0.08 2.0 0.045 0.030 1.0 8.0-11.0 18.0-20.0
F304H 0.04-0.10 2.0 0.045 0.030 1.0 8.0-11.0 18.0-20.0
F304L(1) 0.030 2.0 0.045 0.030 1.0 8.0-13.0 18.0-20.0
F304N(2) 0.08 2.0 0.045 0.030 1.0 8.0-10.5 18.0-20.0
F304LN(2) 0.030 2.0 0.045 0.030 1.0 8.0-10.5 18.0-20.0
F309H 0.04-0.10 2.0 0.045 0.030 1.0 12.0-15.0 22.0-24.0
F310 0.25 2.0 0.045 0.030 1.0 19.0-22.0 24.0-26.0
F310H 0.04-0.10 2.0 0.045 0.030 1.0 19.0-22.0 24.0-26.0
F310MoLN 0.030 2.0 0.030 0.015 0.40 21.0-23.0 24.0-26.0 2.0-3.0 N 0.10-0.16
F316 0.08 2.0 0.045 0.030 1.0 10.0-14.0 16.0-18.0 2.0-3.0
F316H 0.04-0.10 2.0 0.045 0.030 1.0 10.0-14.0 16.0-18.0 2.0-3.0
F316L(1) 0.030 2.0 0.045 0.030 1.0 10.0-15.0 16.0-18.0 2.0-3.0
F316N(2) 0.08 2.0 0.045 0.030 1.0 11.0-14.0 16.0-18.0 2.0-3.0
F316LN(2) 0.030 2.0 0.045 0.030 1.0 11.0-14.0 16.0-18.0 2.0-3.0
F316Ti 0.08 2.0 0.045 0.030 1.0 10.0-14.0 16.0-18.0 2.0-3.0 (3) N 0.10 max
F317 0.08 2.0 0.045 0.030 1.0 11.0-15.0 18.0-20.0 3.0-4.0
F317L 0.030 2.0 0.045 0.030 1.0 11.0-15.0 18.0-20.0 3.0-4.0
F321 0.08 2.0 0.045 0.030 1.0 9.0-12.0 17.0-19.0 (4)
F321H 0.04-0.10 2.0 0.045 0.030 1.0 9.0-12.0 17.0-19.0 (5)
F347 0.08 2.0 0.045 0.030 1.0 9.0-13.0 17.0-20.0 (6)
F347H 0.04-0.10 2.0 0.045 0.030 1.0 9.0-13.0 17.0-20.0 (7)
F348 0.08 2.0 0.045 0.030 1.0 9.0-13.0 17.0-20.0 (6) Co 0.20
Ta 0.10
F348H 0.04-0.10 2.0 0.045 0.030 1.0 9.0-13.0 17.0-20.0 (7) Co 0.20
Ta 0.10

Notes:

  1. Grades F304, F304L, F316, and F316L shall have a maximum Nitrogen of 0.10%.
  2. Grades F304N, F316N, F304LN, and F316LN shall have a Nitrogen of 0.10 to 0.16%.
  3. Grade F316Ti shall have a Titanium content five times above the Carbon plus Nitrogen and not more than 0.70%.
  4. Grade F321 shall have a Titanium content five times above the Carbon and not more than 0.70%.
  5. Grade F321H shall have a Titanium content four times above the Carbon and not more than 0.70%.
  6. Grades F347 and F348 shall have a Niobium content ten times above the Carbon and not more than 1.10%.
  7. Grades F347H and F348H shall have a Niobium content above than eight times the Carbon and not more than 1.10%.

 

ASTM A182 PRESSURE RATING

(Max working pressure of carbon stainless steel flanges ASTM A182 – by Class, in bars)

TEMP. C 150# 300# 400# 600# 900# 1500# 2500#
-29 to 38 15.9 41.4 55.2 82.7 124.1 206.8 344.7
50 15.3 40 53.4 80 120.1 200.1 333.5
100 13.3 34.8 46.4 69.6 104.4 173.9 289.9
150 12 31.4 41.9 62.8 94.2 157 261.6
200 11.2 29.2 38.9 58.3 87.5 145.8 243
250 10.5 27.5 36.6 54.9 82.4 137.3 228.9
300 10 26.1 34.8 52.1 78.2 130.3 217.2
325 9.3 25.5 34 51 76.4 127.4 212.3
350 8.4 25.1 33.4 50.1 75.2 125.4 208.9
375 7.4 24.8 33 49.5 74.3 123.8 206.3
400 6.5 24.3 32.4 48.6 72.9 121.5 202.5
425 5.5 23.9 31.8 47.7 71.6 119.3 198.8
450 4.6 23.4 31.2 46.8 70.2 117.1 195.1

To learn more about flange pressure rating, read this article.

 

ASTM A182 MECHANICAL PROPERTIES

ASTM A182 Grade Minimum Tensile Strength
in MPa
Minimum Yield point
in Mpa
Minimum Elongation
in %
Minimum Reduction of in
min, %
ASTM A182 F304 515 205 30 50
ASTM A182 F304L 485 170 30 50
ASTM A182 F316 515 205 30 50
ASTM A182 F316L 485 170 30 50
ASTM A182 F321 515 205 30 50

 

ASTM A182 RECOMMENDED SERVICE

MATERIAL MATERIAL GROUP RECOMMENDED SERVICE
A182-F304 18% Cr, 8% Ni Stainless Steel Corrosive services and atmospheres from -450°F to 1000°F (-268°C to 537°C)
A182-F316 18% Cr, 8% Ni, 2% Mo Stainless Steel High resistance to corrosion from -450°F to 1000°F (-268°C to 537°C).

 

ASTM vs. EN STAINLESS STEEL FLANGE MATERIALS

Flanges Material Grades: Comparison European and American Standards
Material number EN ASTM
Stainless Steel Flange Materials
1.4541 X 6 CrNiTi 18 10 X6CrNiTi18-10 A 182 Grade F321
1.4571 X 6 CrNiMoTi 17 12 2 X6CrNiMoTi17-12-2 A 182 Grade F316Ti
1.4301 X 5 CrNi 18 10 X5CrNi18-10 A 182 Grade F304
1.4306 X 2 CrNi 19 11 A 182 Grade F304L
1.4307 – X2CrNi18-9 A 182 Grade F304L
1.4401 X 5 CrNiMo 17 12 2 X5CrNiMo17-12-2 A 182 Grade F316
1.4404 X 2 CrNiMo 17 13 2 X2CrNiMo17-12-2 A 182 Grade F316L
1.4462 X 2 CrNiMoN 22 5 3 X2CrNiMoN22-5-3 A 182 Grade F51 (Duplex)
1.4529 X 1 NiCrMoCuN 25 20 6 X1NiCrMoCuN25-20-7 UNS N 08926
1.4539 X 1 NiCrMoCuN 25 20 5 X1NiCrMoCu25-20-5 A 182 Grade F904L
1.4547 – X1CrNiMoCuN20-18-7 UNS S 3125