Stainless Steel 347H Round Bar
➡️ SS 347H | UNS S34709 | EN 1.4961
➡️ ASTM, EN, JIS & International Standards
➡️ Supply Conditions
➡️ Multiple Diameters & Supply Lengths
➡️ Global Export & International Delivery
Country of Origin:
Europe, Japan, USA
Material Type:
Stainless Steel
UNS Number:
S34709
Wr. No.:
1.4961 (nearest)
MTC Available:
EN 10204 3.1
Product Description for Stainless Steel 347H Round Bar
Stainless Steel 347H Round Bar is sold as UNS S34709 and W.Nr. 1.4961 (nearest). The bar standard is ASTM A479 / A479M. Dimensional and surface requirements sit in ASTM A484 / A484M. EN and GB/T list an equivalent grade. JIS and KS do not.
The grade is the high-carbon niobium-stabilised variant of 347, with carbon between 0.04% and 0.10% and niobium at a minimum of eight times carbon. It provides the highest creep-rupture strength of the common stabilised austenitic grades and is widely used for pressure-retaining components operating between 525 C and 815 C in refinery and boiler service.
The delivery condition is solution annealed (Condition A, +AT). Available finishes include hot finished and pickled, cold drawn, peeled, turned, centreless ground and polished, and the choice follows the tolerance and surface quality the part needs. Common diameters run 3 mm to 500 mm, larger on request by forging, in 3 to 6 m random lengths or cut to size. The grade cannot be hardened by heat treatment; higher strength is obtained only through cold working.
It is machined into refinery heater components, boiler supports, bolting and machined hot-service parts. The main buyers are in refining, petrochemical, power generation and high-pressure boiler manufacturing. Material normally ships against an EN 10204 3.1 certificate showing heat analysis, mechanical results and delivery condition. Density is around 8.00 g/cm3 and the modulus of elasticity about 193 GPa. Third party inspection, positive material identification and non-destructive examination can be added at order stage. The melting range is roughly 1400 – 1425 C.
Common Applications of Stainless Steel 347H Round Bar
➡️ Machined shafts, spindles, valve stems, pump sleeves and pins for food, beverage, dairy and pharmaceutical equipment, where the passive chromium oxide film resists both product acids and caustic clean-in-place chemicals.
➡️ Fasteners, studs, bolts, threaded rod and anchor components produced from bar stock, chosen for corrosion resistance combined with the ductility needed for cold heading and thread rolling.
➡️ Chemical, water treatment and general process plant parts such as agitator shafts, flange blanks, nozzles and support components handling water, steam and mildly corrosive media free of significant chlorides.
➡️ Architectural and structural hardware including handrail stanchions, balustrade fittings, tension rods and bollards, where a bright ground or polished bar finish provides both appearance and low maintenance.
International Equivalent Grade for SS 347H Round Bar
Standard
Country / Region
Grade
ASTM A479 / A479M
USA
Type 347H (UNS S34709)
ASME SA-479
USA
Type 347H (UNS S34709)
EN 10216-2 / EN 10028-7
Europe / EU
1.4961 (X8CrNiNb16-13) - nearest equivalent
BS EN 10216-2
United Kingdom
1.4961 (X8CrNiNb16-13)
JIS G4303
Japan
No equivalent grade listed in JIS G4303
GB/T 20878
China
07Cr18Ni11Nb (S34779)
KS D 3706
South Korea
No equivalent grade listed in KS D 3706
ISO 15510
International
No direct equivalent identified
Technical Specification for Stainless Steel 347H Round Bar
Specification
Value
Unit
Material
Stainless Steel
-
Grade
347H / UNS S34709 / W.Nr. 1.4961 (nearest)
-
Product Form
Round Bar / Rod
-
Standard
ASTM A479 / A479M
-
Diameter
3 - 500 (larger by forging on request)
mm
Length
3 - 6 (random mill length) or cut to length
m
Manufacturing Process
Hot rolled, forged or cold finished
-
Production Route
EAF + AOD / VOD refining, continuous cast or ingot, hot rolled or forged
-
Surface Finish
Hot-finished and pickled, cold-drawn, peeled, turned, ground or polished
-
Heat Treatment / Delivery Condition
Solution annealed (condition a, +at)
-
Tolerance Standard
ASTM A484 / A484M
-
Carbon Equivalent (CEV)
Not applicable (CEV applies to carbon and low-alloy steels)
-
Density
8.00 (nominal)
g/cm3
Melting Range
1400 - 1425 (typical)
C
Thermal Conductivity at 100 C
16.1 (typical)
W/m.K
Coefficient of Thermal Expansion (0-100 C)
16.6 (typical)
10-6/K
Specific Heat (0-100 C)
500 (typical)
J/kg.K
Electrical Resistivity at 20 C
0.73 (typical)
micro-ohm.m
Modulus of Elasticity at 20 C
193 (typical)
GPa
Magnetic Properties
Non-magnetic in the solution annealed condition, slight magnetism may develop after cold work
-
Applicable Testing / Inspection Standard
ASTM A370 (mechanical testing), ASTM E112 (grain size, where required), ASTM A262 (intergranular corrosion, when specified)
-
Certification / Inspection Documents
EN 10204 3.1 mill test certificate standard, 3.2 third-party, PMI, ultrasonic and dye-penetrant examination available on request
-
Technical Specifications
Get the key technical specifications for Stainless Steel 347H Round Bar
Orders are normally placed to ASTM A479 / A479M, with ASTM A484 / A484M carrying the dimensional side. European practice specifies the same steel to EN as 1.4961 (X8CrNiNb16-13). Whichever it is, the standard, the condition and any extra testing belong on the purchase order.
Solution treatment is carried out at approximately 1050-1120 C with rapid cooling. ASTM A479 requires an austenite grain size of ASTM No. 7 or coarser, and a stabilising anneal may be applied where specified.
Bar reaches its finish two ways: hot rolling or forging followed by heat treatment and pickling, or a further cold operation such as drawing, peeling, turning or grinding. Tolerances on diameter, out of round, straightness and length depend on both size and finish class.
The grade is extensively used in fluid catalytic cracking units and in high-temperature steam service, where both creep strength and resistance to polythionic acid stress corrosion cracking during shutdown are relevant.
Treat the physical properties as typical producer figures; the standard does not set them. Mechanical testing follows ASTM A370 and everything tested appears on the certificate.
Chemical Composition for Stainless Steel 347H Round Bar
Element
Symbol
Min
Max
Unit
Carbon
C
0.04
0.10
%
Manganese
Mn
-
2.00
%
Silicon
Si
-
1.00
%
Phosphorus
P
-
0.045
%
Sulfur
S
-
0.030
%
Chromium
Cr
17.00
19.00
%
Nickel
Ni
9.00
12.00
%
Niobium (Columbium)
Nb (Cb)
8 x C
1.10
%
Chemical Composition
View the chemical composition and applicable material limits for SS 347H Round Bar
The higher carbon minimum supplies creep strength, while niobium at eight times carbon guarantees stabilisation. The balance is set so that enough carbon remains available for strengthening without leaving chromium vulnerable.
Chromium runs 17.00 to 19.00% here, and it is what makes the steel stainless: it builds the passive oxide film that resists attack. Nickel at 9.00 to 12.00% stabilises the structure and improves ductility and toughness. The standard also fixes niobium (columbium) 8 x C to 1.10%. Carbon is held between 0.04 and 0.10%.
Manganese and silicon go in as deoxidisers during melting and add a little strength. Phosphorus and sulphur are residuals, held low because they hurt hot working, welding and corrosion resistance; sulphur is raised only when a free machining variant is wanted.
Limits differ a little between the ASTM, EN, JIS, GB/T and KS versions. That usually makes no practical difference, but it can in aggressive or high temperature duty, which is why the certified heat analysis is worth reading against the ordered specification. Chemical analysis is carried out to ASTM A751. Where the composition table shows no limit for an element, the standard sets no requirement and the element need not be determined or reported.
Mechanical Properties for Stainless Steel 347H Round Bar
Mechanical Property
Value
Unit
Tensile Strength (ASTM A479, annealed)
515 (min)
MPa
Yield Strength 0.2% (ASTM A479, annealed)
205 (min)
MPa
Elongation in 50 mm (ASTM A479, annealed)
30 (min)
%
Reduction of Area (ASTM A479, annealed)
40 (min)
%
Hardness (Brinell)
Not specified by ASTM A479 / A479M for this grade (typically 150 - 190 HBW as supplied)
HBW
Charpy V-Notch Impact at room temperature
60 - 120 (typical)
J
Modulus of Elasticity
193 (typical)
GPa
Mechanical Properties
Check the key mechanical properties and performance requirements of SS 347H Round Bar
Room-temperature minima match 347, but selection is normally based on ASME allowable stress values and creep-rupture data in the intended temperature range.
Values relate to the solution annealed condition, verified by ASTM A370 tensile testing. Drawing or grinding work hardens the surface, which pushes as supplied strength above the specified minimum and pulls ductility down. The austenitic structure keeps its toughness down to cryogenic temperatures and shows no transition point.
Design to the minima of the ordered standard and condition; the certificate carries what the heat actually achieved. Bar diameter has an effect of its own, through cooling rate in heat treatment and the amount of working the section received.
In selection terms, moderate strength combined with very high ductility and toughness favours components that must be formed, welded or extensively machined rather than carry high stress in thin sections. Where greater strength is needed at similar corrosion resistance, cold-worked bar, a duplex grade or a precipitation-hardening grade is normally evaluated instead. Machinability is moderate, and work hardening during cutting should be managed with sharp tooling, positive feed and rigid setups.
Dimension / Sizes for Stainless Steel 347H Round Bar
Dimension / Size
Value
Unit
Diameter (standard supply range)
3 - 500 (larger by forging on request)
mm
Standard Length
3 - 6 (random mill length)
m
Custom Length
Cut to length available on request
-
Diameter Tolerance
Per ASTM A484 / A484M, varies with size and finish class
-
Length Tolerance
Per ASTM A484 / A484M or as agreed on the order
-
Straightness Tolerance
Per ASTM A484 / A484M or as agreed on the order
-
End Condition
Square cut, saw cut, chamfered or as ordered
-
Surface Finish
Hot-finished and pickled, cold-drawn, peeled, turned, ground or polished
-
Available Size Range (cold-finished bar)
3 - 100 (typical commercial capability)
mm
Available Size Range (hot-finished and forged bar)
16 - 500 (typical commercial capability)
mm
Cut-to-Length Availability
Available, tolerance to be agreed at order stage
-
Applicable Dimensional Standard
ASTM A484 / A484M
-
Dimensions & Sizes
Explore available diameters, lengths, and dimensional requirements for SS 347H Round Bar
Pricing for Stainless Steel 347H Round Bar
Round Bar Prices are generally quoted per kilograms or meters tonnes and can fluctuate with the global raw material and market prices. The final price will depend on a variety of factors, including the grade size, diameter, length, surface finish, the quantity and whether the bars are cut to length or in standard lengths.
For smaller quantities, we can also quote per metre or per piece basis once the required dimensions have been confirmed. Container-loads or orders that are larger in size are typically priced per tonne, based upon the specifications required and the supply conditions.
Please provide your desired dimensions, grades, length number, and end for a current quote including the lead time applicable and details for certification.
Pricing
Get current Stainless Steel 347H Round Bar pricing based on size, quantity, grade, finish, and delivery requirements.
Why Choose Us
Euro Steel Bars is an international distributor, stockist and exporter of stainless round steel bars that cover carbon, stainless alloy, special grades. We stock a variety of sizes and grades. We guarantee every order with mill test certificates as well as full quality-assurance documentation. Our name speaks to our roots: European-sourced materials that is backed by the certificates and rigor that buyers from Asia as well as the Gulf and Africa are looking for.
Each bar we deliver is accompanied by EN 10204 3.1 mill test certificates as well as complete documentation of quality, so what you receive corresponds to what’s written in the documents. We carry a selection of sizes and grades ready for transport, and cut length upon the request of customers, which results in quicker lead times, whether you’re ordering just a one-off spec or a complete project tonnage.
We operate an actual wholesale business that is that is supported with an internationally-operated supply chain therefore we are able to serve fabricators sourcing one grade the same way in the same way as an EPC contractor who is placing a large order. Our clients include manufacturers, fabricators EPC construction companies, engineers oil and gas projects as well as construction companies. we design our inventory as well as documentation to show what buyers need to bring projects forward.
Our customers trust us across Qatar, Oman, Bahrain, Kuwait, Jordan, Malaysia, Singapore, Thailand, Taiwan, Turkey, Italy and South Africa. If you’re looking to source an Gulf energy project, or a construction project within Southeast Asia, you get the same quality of certified material, the exact documentation, and the exact delivery procedure.
Frequently Asked Questions
What is Stainless Steel 347H Round Bar?
What standard does Stainless Steel 347H Round Bar comply with?
What are the equivalent grades of Stainless Steel 347H Round Bar?
What sizes and lengths are available in Stainless Steel 347H Round Bar?
What are the key mechanical properties of Stainless Steel 347H Round Bar?
What is the typical chemical composition of Stainless Steel 347H Round Bar?
Can Stainless Steel 347H Round Bar be supplied cut to length or with a specific surface finish?
Why is 347H used in refinery service?
Request A Quote
Need a specific grade, size or quantity? Get pricing and availability for your requirement.