321 Stainless Steel Flange Supplier: 321, 321H
321 & 321H Equivalent Designations
321 Stainless Steel
- UNS S32100
- EN 1.4541
- JIS SUS321
- GOST 08Kh18N10T
- AFNOR Z6CNT18-10
321H Stainless Steel
- UNS S32109
- EN 1.4878
- JIS SUS321H
- GOST 12Kh18N10T
- AFNOR Z6CNT18-12
Chemical Composition of 321 Stainless Steel Flange (321/H)
| Element | C | Cr | Ni | Ti | Mn | Si | P | S | N | Fe |
|---|---|---|---|---|---|---|---|---|---|---|
| 321 | ≤ 0.08% | 17.0% – 19.0% | 9.0% – 12.0% | 5 × (C + N) ~ 0.7 | ≤ 2.0% | ≤ 1.0% | ≤ 0.045% | ≤ 0.030% | ≤ 0.10% | Balance |
| 321H | 0.04% – 0.10% | 17.0% – 19.0% | 9.0% – 12.0% | 4 × (C + N) ~ 0.7 | ≤ 2.0% | ≤ 1.0% | ≤ 0.045% | ≤ 0.030% | ≤ 0.10% | Balance |
The Core Role of Formulation Design
- Stabilizing Effect of Titanium:
Titanium has a much higher affinity for carbon than chromium.Within the sensitization temperature range of 427°C to 816°C,titanium preferentially combines with carbon to form titanium carbide,thereby preventing the precipitation of chromium carbide at grain boundaries and avoiding intergranular corrosion caused by “chromium depletion.” - Carbon Content in 321H:
Although 321 can also be used at high temperatures,321H strictly limits the carbon content to no less than 0.04%.This provides the flange with superior creep resistance and high-temperature structural strength in environments above 537°C (1000°F). - Dual Certification:
In practical engineering applications,the carbon content of many materials falls between 0.04% and 0.08%,so it is common to find flanges that are dual-certified to meet both the 321 and 321H standards.As a provider of stainless steel piping system solutions with a decade of experience,Kaysuns is capable of supplying these products using our state-of-the-art manufacturing equipment.
Have a requirement?
Contact Us For More Information
Mechanical Properties of 321 Stainless Steel Flange Series
| Performance Metrics | 321 | 321H |
|---|---|---|
| Tensile Strength | ≥ 515 MPa (75 ksi) | ≥ 515 MPa (75 ksi) |
| Yield Strength 0.2% | ≥ 205 MPa (30 ksi) | ≥ 205 MPa (30 ksi) |
| Elongation in 50mm | ≥ 30% – 40% | ≥ 30% – 40% |
| Hardness | ≤ 217 HBW(95 HRB) | ≤ 217 HBW(95 HRB) |
Minimum Yield Strength VS Temperature
| Temperature (°C) | Temperature (°F) | 321 (MPa) | 321H (MPa) |
|---|---|---|---|
| 20 | 68 | 205 | 205 |
| 100 | 212 | 170 | 170 |
| 200 | 392 | 150 | 150 |
| 300 | 572 | 135 | 135 |
| 400 | 752 | 125 | 125 |
| 500 | 932 | 118 | 118 |
| 600 | 1112 | 110 | 112 |
| 700 | 1292 | 102 | 105 |
Maximum Allowable Stress VS Temperature
| Temperature (°C) | Temperature (°F) | 321 (MPa) | 321H (MPa) | Performance Note |
|---|---|---|---|---|
| 40 | 100 | 138 | 138 | Equivalent performance |
| 150 | 300 | 121 | 121 | Standard thermal decline |
| 300 | 572 | 102 | 102 | |
| 450 | 842 | 94 | 94 | |
| 550 | 1022 | 86 | 90 | 321H begins to outperform |
| 650 | 1202 | 45 | 62 | Significant Creep Strength gap |
| 750 | 1382 | 16 | 24 | 321H is 50% stronger here |
| 815 | 1500 | 7.5 | 11 | Upper limit for pressure parts |
Below this temperature,the strength of 321 and 321H is nearly identical.Above this threshold,creep rupture strength becomes the determining factor,at which point 321H (due to its higher carbon content and coarser grain size) significantly outperforms 321.
Our Key Capabilities in Manufacturing 321/H SS Flanges
Precise Chemical & Carbon Control
We are able to precisely control the carbon content of 321H within the range of 0.04% to 0.10% and strictly adhere to the stabilization ratio of Ti = 5 × (C + N) to 0.70.
This precise control ensures that the flanges possess excellent resistance to sensitization while maintaining outstanding mechanical strength at high temperatures.
Solution Annealing & Grain Size Control
Forging & Sealing Surface Machining
Intergranular Corrosion & NDT Testing
Applications of 321 Stainless Steel Flange (321/H)
321 Stainless Steel Flange
- Aerospace Engine & Exhaust Systems
- Oil Refining & Chemical Processing
- Power Generation & Boilers
- Automotive Exhaust & Turbochargers
- Waste Incineration & Industrial Furnaces
321H Stainless Steel Flange
- Fluid Catalytic Cracking Units
- Supercritical Boilers & Superheaters
- Petrochemical Pyrolysis Furnaces
- Thermal Oxidizers & Heat Recovery
- High-Temperature Pressure Vessels
FAQs About 321 Stainless Steel Flange Grades
According to the ASTM A182 standard,the grain size of 321H flanges must be ASTM No. 7 or coarser.This is because,in extremely high-temperature environments,a coarse-grained structure exhibits better creep resistance than a fine-grained structure,thereby preventing slow,permanent deformation of the flange under prolonged exposure to high temperatures and pressures.
This depends on your operating environment.In ambient or low-temperature conditions,it can be substituted.
However,if the operating temperature ranges from 427°C to 816°C,it cannot be substituted.Although 304L stainless steel flanges have a lower carbon content that can slow corrosion,321 provides better titanium stabilization within this temperature range.
This is generally not necessary.
The titanium content in 321 effectively suppresses the precipitation of chromium carbides in the heat-affected zone during welding.As a result,321 flanges retain excellent corrosion resistance after welding without requiring a time-consuming “post-weld annealing” process.
When requesting a quote or placing a purchase order with us,please provide the following information:
Flange type + RF/RTJ/FF + Grade (including pipe SCH for WN and SW flanges) + Size + Material + Standard + Order quantity
For example,if you wish to purchase 100 raised face weld neck flanges for your system,with a pipe size of 8 inches SCH40S,a pressure rating of 300,a material of 321 stainless steel,and a pipe design compliant with ASME standards,the product description would be as follows:
WNRF flange,8 inches,300 psi,SCH40S,A182 F321,ASME B16.5,100 pieces
Contact Us
- RM901 No.22 Tangjiaqiao Road Wenzhou China
- +86 577 8551 1171
- [email protected]
- https://www.kaysuns.com/
