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
- Large Scale Enterprise – Metallica is biggest stock holding, manufacturing and processing company of SS 347/347H 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 347/347H Seamless Pipes– All SS 347/347H 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 347/347H Seamless Pipes – Marking on all pipes is as per the predefined rules in the specification.
- Test Certificates & Inspection of SS 347/347H 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 347/347H, 1.4550/1.4961, UNS S34700/S34709 seamless pipes with shortest delivery time.
- We can produce either standard or non-standard of the stainless steel 347/347H seamless pipes.
What is 347/347H Stainless Steel?
Type 347 is a niobium stabilized chromium nickel austenitic stainless steel with corrosion resistance similar to 304/304L. 347 stainless steel is a columbium/tantalum stabilized austenitic chromium-nickel stainless steel. This grade is typically used in the 800-1500˚F temperature range where it is stabilized against chromium carbide precipitation by the addition of niobium, which results in the precipitation of niobium carbides. Type 347 has excellent intergranular corrosion resistance after exposure to this temperature range, and this grade resists oxidation up to 1500˚F and has higher creep and stress rupture properties than 304/304L. It also possesses good low temperature toughness and is non-magnetic in the annealed condition. This material is stabilized against chromium carbide formation by the addition of columbium and tantalum. Since these elements have a stronger affinity for carbon than chromium, columbium-tantalum carbides precipitate within the grains instead of forming at the grain boundaries. 347 is non-magnetic.
Stainless Steel 347H is another stainless steel in a class of metals labeled of precipitation-hardened steels. It possesses many of the same properties and characteristics of stainless steel 347. In addition to its higher carbon content, the alloy is stabilized with an addition of columbium, or sometimes tantalum. Both these properties allow 347H to be exposed to higher temperatures than both 347 and the 304 stainless steel grades can withstand. Because of its elevated resistance to corrosion, 347H is often applied in high stress, high corrosion environments where exposure tends to be severe. High temperature manufacturing, steam pipes, boiler tubes, chemical processes and steam servicing all benefit from 347H’s resilience. This resilience in turn is due to the potentially elevated levels of chromium in 347H’s composition. The metal can contain anywhere from 4-30%.
The metal displays high workability under most common welding techniques. It can be treated with heat, however, it will not respond. Only cold working is sufficient to increase 347H’s toughness and strength.
Manufacturing Range for Stainless Steel 347/347H, 1.4550/1.4961, UNS S34700/S34709 Seamless or Welded Stainless Steel Pipes
| Product | ASTM A312 TP347/TP347H, 1.4550/1.4961, UNS S34700/S34709 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 TP347/TP347H, 1.4550/1.4961, UNS S34700/S34709 Seamless or Welded Stainless Steel Pipes
| ELEMENT | 347 | 347H |
| NI | 17.0 – 20.0 | 17.0 – 19.0 |
| 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 |
| NB | 10xC – 1.10 | 8xC – 1.10 |
Physical Properties ASTM A312 TP347/TP347H, 1.4550/1.4961, UNS S34700/S34709 Seamless or Welded Stainless Steel Pipes
| Units | Temperature in °C |
| Density | 7.97 g/cm³ |
| Specific Heat | 0.12 Kcal/kg.C |
| Melting Range | 1398 – 1446 °C |
| Modulus of Elasticity | 193 KN/mm² |
| Electrical Resistivity | 72 µΩ.cm |
| Coefficient of Expansion | 16.0 µm/m °C |
| Thermal Conductivity | 16.3 W/m -°K |
| Annealed | 1040 – 1100 (°C) / 1900 – 2000 (°F) |
| Quenched | Rapid Air/Water |
Mechanical Properties ASTM A312 TP347/TP347H, 1.4550/1.4961, UNS S34700/S34709 Seamless or Welded Stainless Steel Pipes
| Tensile Strength (ksi) | 0.2% Yield Strength (ksi) | Elongation% in 2 inches |
| 75 | 30 | 40 |
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] |
