# SUS 317J1 Forgings

**SUS 317J1 is a Japanese austenitic stainless steel of nominal 18Cr-16Ni-5Mo, specified in JIS G 4304. Jiangyin Jiangnan Metal Co., Ltd. melts and forges it at No.1 Chengxiqiao Road, Zhouzhuang Town, Jiangyin City, Jiangsu Province, China, as seamless rolled rings to 6,000 mm outside diameter and single pieces to 30 tonnes.**

Five percent molybdenum and sixteen percent nickel buy service life in liquor that eats 316L. Japanese material references place SUS 317J1 where SUS 317L and SUS 316L run out of margin: heat exchangers carrying chloride-bearing liquor, acetic acid plant, phosphoric acid plant and bleaching equipment.

Contact: sales@steelforgepieces.com | +86 189 2135 9659
Canonical page: https://www.steelforgepieces.com/Stainless-Steel/SUS-317J1.html

## Grade record

| Field | Detail |
|---|---|
| Grade | SUS 317J1 |
| Standard | JIS G 4304 |
| Nominal composition | 18Cr-16Ni-5Mo |
| Structure | Austenitic, non-magnetic |
| Supply condition | Solution annealed and quenched |
| Chinese equivalent | 0Cr18Ni16Mo5 |
| Maximum rolled ring OD | 6,000 mm |
| Maximum single piece | 30,000 kg |
| Minimum order | 10 kg, no minimum piece count |
| Lead time | 20 to 60 days |

## Chemical composition

JIS G 4304 limits, mass %.

| Element | Limit |
|---|---|
| Carbon, C | 0.040 max |
| Silicon, Si | 1.00 max |
| Manganese, Mn | 2.50 max |
| Phosphorus, P | 0.045 max |
| Sulfur, S | 0.030 max |
| Chromium, Cr | 16.00 – 19.00 |
| Nickel, Ni | 15.00 – 17.00 |
| Molybdenum, Mo | 4.00 – 6.00 |
| Iron, Fe | Balance |

Several English-language grade databases publish an 18–20 Cr / 11–15 Ni / 3–4 Mo analysis under the name SUS 317J1. That is not what JIS specifies and appears to be plain SUS 317 data filed under the wrong heading. Two of those sites also list a yield strength above their own tensile strength and a density range spanning a factor of two.

## Mechanical properties

JIS acceptance limits, solution-treated condition.

| Property | Requirement |
|---|---|
| 0.2 % proof stress | 175 N/mm² min |
| Tensile strength | 480 N/mm² min |
| Elongation | 40 % min |
| Hardness, Brinell | 187 HBW max |
| Hardness, Rockwell B | 90 HRBS / HRBW max |
| Hardness, Vickers | 200 HV max |

Heavy forged sections behave differently from bar stock. Where a project needs guaranteed properties at a stated depth, the test location and sampling plan are agreed at order stage.

## Where the grade sits

SUS 317J1 is a Japanese designation with no AISI number of its own. The Dandong Foundry stainless grade comparison table pairs it with the Chinese grade 0Cr18Ni16Mo5, matching the 18Cr-16Ni-5Mo chemistry. We are not aware of a published one-to-one European or UNS equivalent.

UNS S31703 (317L) and UNS S31753 (317LN) are relatives, not substitutes. 317L runs leaner on nickel and molybdenum; 317LN adds nitrogen for strength.

## How it is made

Stainless grades run through a 25 t electric arc furnace, a ladle furnace for desulphurisation and alloy trim, then vacuum oxygen decarburisation where low carbon or tight nitrogen control matters. A grade with a 0.040 % carbon ceiling is exactly the case VOD exists for.

Steel is then cogged under a 2,000, 4,000 or 6,300 tonne press, or punched and rolled on one of three radial-axial ring mills. Fourteen heat treatment furnaces sit on the same site, including a 15 m deep well furnace for vertical quenching of long shafts. No forging, heat treatment or machining step is subcontracted.

SUS 317J1 is austenitic and cannot be hardened by heat treatment. It work hardens readily during machining, so positive rake tooling, a rigid setup, heavy coolant, constant feed and chip breakers all apply.

## Forms supplied

- Seamless rolled rings, contoured rings, forged rings, retaining rings, valve seat rings
- Solid discs, tube sheets, vessel covers
- Stepped shafts, eccentric shafts, spindles, pinion shafts
- Round, flat and square bar, gear blanks
- Weld neck, blind, slip-on, lap joint and orifice flanges
- Sleeves, bushings, couplings, cylinders bored from solid
- Valve bodies, bonnets, stems, blocks, nozzles, manifolds

## Size envelope

| Form | Limit | Set by |
|---|---|---|
| Seamless rolled rings | OD 50 – 6,000 mm | 6 m, 3 m and 1 m radial-axial ring mills |
| Forged shafts | to 14,000 mm turned | C61160 lathe, 15 m well furnace |
| Discs, tube sheets, blocks | to 5,000 mm diameter | 5,000 mm vertical turning lathe |
| Bored cylinders, hollow shafts | 1,600 mm dia × 10,000 mm | CNC deep-hole drilling machine |
| Single piece weight | to 30,000 kg | 60 t heat size, 6,300 t press |

## Testing and certification

EN 10204 3.1 as standard, EN 10204 3.2 third-party certification on request. Ultrasonic examination to EN 10228-3, SEP 1921 or ASTM A388 as nominated. Supplementary testing on request: intergranular corrosion testing, ferrite measurement, positive material identification, impact testing, hardness survey. The works holds CCS, BV, DNV, LR and NK approvals.

## Ordering

Send a drawing to sales@steelforgepieces.com. Without one, outside diameter, inside diameter, height or length, quantity, governing standard and supplementary tests are enough for a budget price. Quotations normally return within one working day.

## Questions

**What is SUS 317J1 stainless steel?**
A Japanese austenitic stainless steel of roughly 18Cr-16Ni-5Mo. The high molybdenum and nickel put it above SUS 317L and SUS 316L, and Japanese material references list it for heat exchangers handling chloride-bearing liquor, acetic acid plant, phosphoric acid plant and bleaching equipment.

**Is SUS 317J1 the same as 317L?**
No. SUS 317J1 carries 15 to 17 % nickel and 4 to 6 % molybdenum, well above 317L. A widely published grade comparison table pairs SUS 317J1 with the Chinese grade 0Cr18Ni16Mo5.

**What size SUS 317J1 forgings can you make?**
Rolled rings from 50 mm to 6,000 mm outside diameter. Shafts turned to 14,000 mm, discs and tube sheets to 5,000 mm diameter, bored cylinders to 1,600 mm diameter by 10,000 mm. Heaviest single piece 30 tonnes.

**Do you melt SUS 317J1 yourselves or buy billet?**
We melt it. Stainless grades run through the electric arc furnace, the ladle furnace and vacuum oxygen decarburisation on the same site as the presses and ring mills.

**Can the grade be hardened by heat treatment?**
No. Austenitic grades gain strength only from cold work. SUS 317J1 is supplied solution annealed and quenched.

**What certification comes with the forgings?**
EN 10204 3.1 as standard, EN 10204 3.2 third-party certification on request. Ultrasonic testing to EN 10228-3, SEP 1921 or ASTM A388.

**What is the minimum order and lead time?**
Minimum order 10 kg with no minimum piece count. Lead time 20 to 60 days.

## Sources

Composition and mechanical limits are the JIS G 4304 values published by susjis.info and by the Caishuku material database citing JIS G 4304-2005. The 0Cr18Ni16Mo5 pairing is from the Dandong Foundry stainless grade comparison table. Plant capacities are our own.

Jiangyin Jiangnan Metal Co., Ltd. | No.1 Chengxiqiao Road, Zhouzhuang Town, Jiangyin City, Jiangsu Province, China | +86 189 2135 9659 | sales@steelforgepieces.com

Last checked 4 October 2026.