A furnace is a device used for high-temperature heating. It is a container that is heated to a very high temperature, so that substances that are put inside it, such as metal, will melt or burn.
The name derives from Latin word fornax, which means oven. The heat energy to fuel a furnace may be supplied directly by fuel combustion, by electricity such as the electric arc furnace, or through induction heating in induction furnaces.
In metallurgy, several specialized furnaces are used. These include:
Furnaces used in smelters, including:
- The blast furnace, used to reduce iron ore to pig iron
Steelmaking furnaces, including:
- Puddling furnace
- Reverberatory furnace
- Bessemer converter
- Open hearth furnace
- Basic oxygen furnace
- Electric arc furnace
- Electric induction furnace
Furnaces used to remelt metal in foundries.
Furnaces used to reheat and heat treat metal for use in:
- Rolling mills, including tinplate works and slitting mills.
- Forges
Source: Wikipedia.org
Why Buy AISI 321/321H, 1.4878/1.4541, UNS S32100/S32109 Seamless Pipes from Metallica Metals?
- Large Scale Enterprise – Metallica is biggest stock holding, manufacturing and processing company of SS 321/321H seamless pipes in India. Our large volume production, sales and purchase enables us to offer our products at the most competitive prices in the industry.
- Testing of Stainless Steel 321/321H Seamless Pipes– All SS 321/321H seamless pipes are subjected to hydrostatic test, eddy current test, chemical and mechanical tests during the various stages of production.
- Marking & Packing of Stainless Steel 321/321H Seamless Pipes – Marking on all pipes is as per the predefined rules in the specification.
- Test Certificates & Inspection of SS 321/321H Seamless Pipes – All our pipes are supplied with Mill test Reports, as per EN 10204 3.1. We can also allow third party inspection of all our products before delivery.
- We have own QC team to control the quality to meet particular standard strictly
- Short Lead Times – We can offer AISI 321/321H, 1.4878/1.4541, UNS S32100/S32109 seamless pipes with shortest delivery time.
- We can produce either standard or non-standard of the stainless steel 321/321H seamless pipes.
What is 321/321H Stainless Steel?
Stainless Steel 321 is a basic austenitic 18/8 steel (Grade 304) blend of chromium and nickel is stabilised by Titanium (321) addition. SS 321 is used because they are not sensitive to intergranular corrosion after heating within the carbide precipitation range of 425-850°C. Stainless Steel 321 is the grade of choice for applications in the temperature range of up to about 900°C, combining high strength, resistance to scaling, embrittlement and phase stability with resistance to subsequent aqueous corrosion. It is protected from temperatures ranging from 800 to 1500° F. The metal displays high strength and resistance to various forms of corrosions, including that from aqueous environments. Type 321 finds application in heavy welding components, along with dynamic environments that are subject to changes. Beyond this, stainless steel 321 has excellent forming characteristics, does not require annealing after being welded, and displays toughness in a range of temperatures. The metal shows strength even when exposed to cryogenic temperatures. Additionally, it is often chosen over Type 304 for its increased resistance to creep and rupture. Both metals may be susceptible to stress corrosion cracking. It is used to manufacture high quality carbon structural steel seamless steel tubes for hot rolling and cold drawing (rolling) of superheated steam pipe, boiling water pipe and locomotive boiler superheated steam pipe, large smoke pipe, small smoke pipe and arch brick.
SS 321H is a modification of SS 321 with a higher carbon content, to provide improved high temperature strength. In addition, 321H is stabilized by an addition of niobium to resist intergranular corrosion. It is also able to withstand higher temperatures than type 321, due to its elevated carbon levels. While 321H displays the same welding and forming characteristics of type 321, the metal cannot be hardened by heat treatment. It is utilized in situations where type 321 cannot withstand the high temperatures, typically those exceeding 1000° F. Type 321H displays better resistance against creep than both 321 and 304 stainless steels. 321H also shows resistance against acid corrosion in a variety of environments. Lower temperatures provide better resistance, but the metal is able to withstand up to a 10% acid solution, that has been diluted, at elevated temperatures. However, the metal shows very little resistance against chlorine or sulfuric solutions at any given temperature. Given their similar composition and characteristics, it is possible for stainless steels 321 and 321H to become dually certified.
Manufacturing Range for Stainless Steel 321/321H, 1.4878/1.4541, UNS S32100/S32109 Seamless or Welded Stainless Steel Pipes
| Product | ASTM A312 TP321/TP321H , 1.4878/1.4541, UNS S32100/S32109 Stainless Steel Pipes |
| Specification | ASTM A312 / A312M Standard Specification for Seamless, Welded, and Heavily Cold Worked Austenitic Stainless Steel Pipes |
| Type | Seamless & Welded |
| Size Range | Size: 1/8” to 24” (10.3mm to 610mm) – Seamless |
| Size:1/8” to 36” (10.3mm to 914mm) – Welded |
| 1/8” OD to 6” OD |
| Thickness | 10s, 20, 40s, 40, 60, 80s, 80, 100, 120, 140, 160, XXH |
| Wall Thickness: 1mm to 60mm |
| Length | 6 Meter, Custom Lengths |
| Other Grades | TP304, TP304L, TP304LN, TP316, TP316L, TP316LN, TP317, TP317/317L, TP321, TP347, TP310S |
| Test Certificates | Material Test Certificates (MTC) as per EN 10204 3.1 and EN 10204 3.2 |
| ASTM Reference Standards | - A262 Practices for Detecting Susceptibility to Intergranular Attack in Austenitic Stainless Steels.
- A370 Test Methods and Definitions for Mechanical Testing of Steel Products.
- A480 A480M Specification for general requirements for Flat-rolled stainless and Heat-Resisting steel plate, sheet, and strip.
- A632 Specification for Seamless and welded austenitic stainless-steel tubing (small-diameter) for general service.
- A1016 A1016M Specification for General Requirements for Ferritic Alloy Steel, Austenitic Alloy Steel, and Stainless-Steel Tubes.
- E527 Practice for Numbering Metals and Alloys in the Unified Numbering System (UNS)
|
| Testing | Mechanical Testing Such as Tensile of Area, Hardness Test, Chemical Analysis – Spectro Analysis, Positive Material Identification – PMI Testing, Flattening Test, Micro and MacroTest, Pitting Resistance Test, Flaring Test, Intergranular Corrosion (IGC) Test |
| Documents | Commercial Invoice, Packing List, Certificate of Origin, Fumigation Certificates, Raw Material Test Reports, Material Traceability Records, Quality Assurance Plan (QAP), Heat Treatment Charts, Test Certificates certifying NACE MR0103, NACE MR0175, Material Test Certificates (MTC) as per EN 10204 3.1 and EN 10204 3.2, Guarantee Letter, NABL approved Laboratory Test Reports |
Chemical Composition of ASTM A312 TP321/TP321H, 1.4878/1.4541, UNS S32100/S32109 Seamless or Welded Stainless Steel Pipes
| ELEMENT | 321 | 321H |
| NI | 9.0 – 12.0 | 9.0 – 12.0 |
| C | 0.08 max | 0.04 – 0.10 |
| MN | 2.0 max | 2.0 max |
| P | 0.045 max | 0.045 max |
| S | 0.030 max | 0.030 max |
| SI | 1.0 max | 1.0 max |
| CR | 17.0 – 19.0 | 17.0 – 19.0 |
| TI | 5(C+N) – 0.70 max | 4(C+N) – 0.70 |
| N | 0.10 max | 0.10 max |
Physical Properties of ASTM A312 TP321/TP321H, 1.4878/1.4541, UNS S32100/S32109 Seamless or Welded Stainless Steel Pipes
| DENSITY | 7.92 g/cm 3 / 0.286 lb/in 3 |
| MELTING POINT | 1398 – 1446 (°C) / 2550 – 2635 (°F) |
| ANNEALED | 1040 – 1100 (°C) / 1900 – 2000 (°F) |
| QUENCH | Rapid Air/Water |
| Coefficient of Thermal Expansion (min/in)-°F | at 68 – 212°F | 9.2 |
| at 68 – 1832°F | 20.5 |
| Thermal Conductivity BTU/hr-ft-°F | at 200°F | 9.3 |
| Specific Heat BTU/lbm -°F | at 32 – 212°F | 0.12 |
| Modules of Elasticity (annealed)2-psi | in tension (E) | 28 x 10 ^6 |
Mechanical Properties of ASTM A312 TP321/TP321H, 1.4878/1.4541, UNS S32100/S32109 Seamless or Welded Stainless Steel Pipes
| Grade | Tensile Strength | Yield Strength 0.2% | Elongation – | Hardness |
| ksi (min.) | Offset ksi (min.) | % in 50 mm (min.) | (Brinell) MAX |
| 321 | 75 | 30 | 40 | 217 |
Other Grades Chemical Composition Comparision
| Grade | UNS | Composition, % in Max. |
| Designation | C | Mn | P | S | Si | Cr | Ni | Mo | N |
| TP304 | S30400 | 0.08 | 2 | 0.045 | 0.03 | 1 | 18.0–20 | 8.0–11 | . . . | . . . |
| TP304L | S30403 | 0.035 | 2 | 0.045 | 0.03 | 1 | 18.0–20 | 8.0–13 | . . . | . . . |
| TP304LN | S30453 | 0.035 | 2 | 0.045 | 0.03 | 1 | 18.0–20 | 8.0–11 | . . . | 0.10-0.16 |
| TP316 | S31600 | 0.08 | 2 | 0.045 | 0.03 | 1 | 16.0–18 | 10.0–14 | 2.00–3 | . . . |
| TP316L | S31603 | 0.035 | 2 | 0.045 | 0.03 | 1 | 16.0–18 | 10.0–15 | 2.00–3 | . . . |
| TP316LN | S31653 | 0.035 | 2 | 0.045 | 0.03 | 1 | 16.0–18 | 10.0–13 | . . . | 0.10-0.16 |
| TP317L | S31700 | 0.035 | 2 | 0.045 | 0.03 | 1 | 18.0–20 | 11.0–15 | 3.0–4 | . . . |
| TP321 | S32100 | 0.08 | 2 | 0.045 | 0.03 | 1 | 17.0–19 | 9.0–12 | . . . | . . . |
| TP347 | S34700 | 0.08 | 2 | 0.045 | 0.03 | 1 | 17.0–19 | 9.0–13 | . . . | . . . |
Other Grades Mechanical Properties Comparision
| Grade | UNS Designation | Tensile Strength, Min. Ksi [MPa] | Yield Strength, Min. Ksi [MPa] |
| TP304 | S30400 | 75 [515] | 30 [205] |
| TP304L | S30403 | 70 [485] | 25 [170] |
| TP316 | S31600 | 75 [515] | 30 [205] |
| TP316L | S31603 | 70 [485] | 25 [170] |
| TP317L | S31703 | 70 [485] | 25 [170] |
| TP321 | S32100 | 75 [515] | 30 [205] |
| TP347 | S34700 | 75 [515] | 30 [205] |
| TP347H | S34709 | 75 [515] | 30 [205] |
