Stainless Steel 317 and 317L are high-molybdenum austenitic stainless steels specifically developed for superior corrosion resistance in highly aggressive chemical environments. With higher molybdenum and chromium content than 316, these grades offer outstanding resistance to pitting, crevice corrosion, and strong acidic solutions. SS 317 provides excellent mechanical strength, while SS 317L, with lower carbon, ensures better weldability and resistance to intergranular corrosion.
Primarily used in chemical processing equipment, acid-handling systems, fertilizer plants, pulp and paper industries, and petrochemical refineries, SS 317/317L are ideal for applications requiring maximum corrosion resistance and long service life under severe chemical exposure.
317/317L STAINLESS STEEL ROUND BAR EQUIVALENT GRADES
STANDARD
UNS
WNR.
JIS
EN
SS 317
S31700
1.4449
SUS 317
–
SS 317L
S31703
1.4438
SUS 317L
X2CrNiMo18-15-4
SPECIFICATION OF STAINLESS STEEL 317/317L ROUND BAR
Stainless Steel Round Bar Specification
ASTM A276 / A479, ASME SA276 / A479
Dimension Standard
EN, DIN, JIS, ASTM, BS, ASME, AISI
Size
14 mm – 300 mm
Thickness
50 mm to 6000 mm Long
Length
1 to 6 Meters, Custom Cut Length
Form
Round, Square, Hex (A/F), Rectangle, Billet, Ingot, Forging Etc.
CHEMICAL COMPOSITION OF STAINLESS STEEL 317/317L ROUND BAR
Grade
C%
Mn%
Si%
P%
S%
Cr%
Mo%
Ni%
N%
317
0.08 max
2.0 max
1.0 max
0.040 max
0.03 max
18.0 – 20.0
3.0 – 4.0
11.0 – 14.0
–
317L
0.035 max
2.0 max
1.0 max
0.040 max
0.03 max
18.0 – 20.0
3.0 – 4.0
11.0 – 15.0
–
MECHANICAL PROPERTIES OF STAINLESS STEEL 317/317L ROUND BAR
Property
Value
Tensile Strength
75,000 psi (515 MPa)
Yield Strength (0.2% Offset)
30,000 psi (205 MPa)
Elongation
35%
PHYSICAL PROPERTIES OF 317/317L STAINLESS STEEL ROUND BAR
Property (Room Temperature)
Value
Unit
Density
7.99
g/cm³
Melting Point
1454
°C (2650 °F)
Specific Heat (0–100°C)
500
J/kg·K
Thermal Conductivity
14.6
W/m·K
Thermal Expansion
16.5
mm/m/°C
Modulus of Elasticity
193
GPa
Electrical Resistivity
7.4
µΩ·cm
💡 Practical Difference in Use
Use Stainless Steel 317 Round Bars when: enhanced resistance to aggressive chemicals, strong mechanical performance, and superior molybdenum content are required for demanding corrosion environments such as acidic and chloride-rich processes.
→ Example: chemical processing shafts, acid handling equipment, pump spindles, heat exchanger supports, and heavy-duty fasteners.
Use Stainless Steel 317L Round Bars when: excellent weldability, reduced risk of intergranular corrosion, and reliable corrosion performance after fabrication are essential for welded structures and pressure applications.
→ Example: welded pipelines, pharmaceutical vessels, chemical storage tanks, fabricated frames, and process equipment assemblies.
Applications of Stainless Steel 317 / 317L Round Bars
Stainless Steel 317 and 317L round bars are widely used in high-corrosion and chemically aggressive environments where strength, reliability, and extended service life are required.
Chemical & Petrochemical Plants: Reactor shafts, pumps, agitators, valves, and fasteners.
Pulp, Paper & Bleaching Systems: Digesters, rollers, chemical circulation components.
When to Choose Stainless Steel 317 vs. 317L Round Bars?
The selection primarily depends on corrosion severity, fabrication method, welding requirements, and lifecycle durability.
Choose SS 317 Round Bars when:
Maximum resistance to chemical attack is required
High molybdenum content improves pitting resistance
Excellent mechanical strength is needed for machined parts
Used in pumps, shafts, fasteners, and acid service equipment
Continuous exposure to corrosive media is expected
Long service life and durability are priorities
Choose SS 317L Round Bars when:
Extensive welding or fabrication is involved
Protection against intergranular corrosion is critical
No post-weld heat treatment is planned
Used in tanks, pipelines, pressure vessels, and frames
Low carbon content improves weld quality and toughness
Stable corrosion resistance after welding is required
Industries That Use Stainless Steel 317 / 317L Round Bars
These grades are preferred in industries where aggressive corrosion resistance, structural integrity, and long-term operational reliability are essential.
Chemical Processing Industry
Used for handling corrosive acids and process chemicals.
Uses
Pumps, valves, agitator shafts, reactors.
Why SS 317?
High molybdenum content improves resistance to chemical attack.
Petrochemical & Refining
Used in aggressive fluid handling and high-pressure systems.
