APPLICATION OF HIGH TEMPERATURE GRADES IN CARBON BLACK INDUSTRY

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1 APPLICATION OF HIGH TEMPERATURE GRADES IN CARBON BLACK INDUSTRY

2 SAFETY FIRST Sandvik s objective is zero harm to our people, the environment we work in, our customers and our suppliers. PROTECTIVE EQUIPMENT FIRST AID KIT ALARM EMERGENCY NUMBER EMERGENCY EXIT ASSEMBLY POINT

3 AGENDA 1. Brief about Sandvik- Tube (Products & Applications) 2. Material Corrosion- Different Types (High Temperature Corrosion) MA for High Temperature Application 4. Suitable grades for High Temperature Service & Carbon Black Equipment 6. Tube Manufacturing process 7. Question and Answers

4 BUSINESS AREAS SANDVIK GROUP SANDVIK MINING SANDVIK MACHINING SOLUTIONS SANDVIK MATERIALS TECHNOLOGY SANDVIK CONSTRUCTION SANDVIK VENTURE

5 SANDVIK MATERIALS TECHNOLOGY MEETING THE ENERGY CHALLENGE OIL & GAS NUCLEAR RENEWABLES ENERGY EFFICIENCY FUEL EFFICIENCY POWER GENERATION NEW TECHNOLOGIES 5

6 HIGH TEMPERATURE APPLICATION 6

7 WHAT IS CORROSION? Definition- Corrosion is the deterioration of a substance (basically metal) or its properties because of a reaction with its environment Different types of Corrosion- o General Corrosion o Localized Corrosion i.e pitting, crevice corrosion etc o Galvanic Corrosion o Environmental Corrosion Cracking o Intergranular Corrosion o High Temperature Corrosion 7

8 CORROSIVE ENVIRONMENTS Corrosive environments are typically classified into four types- o Atmospheric o Underground o Liquid o High Temperature 8

9 WHAT IS A HIGH TEMPERATURE APPLICATION? Above 650 deg C (1200 Deg F) Why? o Above this temperature the proof (yield) strength of the material can not be used as a design parameter for the system o Creep strength takes over o Wet corrosion mechanisms are replaced by high temperature corrosion mechanisms o Structural stability becomes more important o Atoms move more at high temperatures 9

10 PROPERTIES- HIGH TEMPERATURE GRADES For a good High Temperature service performance materials should have following properties- o Physical Stability o Maintenance of good mechanical Integrity o Adherence to the substrate o Should not allow rapid corrosion o Strength 10

11 CB PRODUCTION FLOW- FURNACE BLACK PROCESS 11

12 THE SOLUTION- SANDVIK 253MA HIGH ALLOYED AUSTENITIC STAINLESS STEEL Sandvik 253MA is an austenitic, chromium-nickel steel contributing to longer tube life and reduced maintenance in a wide range of high-temperature applications Alloyed with rare earth metals (REM), Sandvik 253MA is characterized by high performance in oxidizing, Sulfidizing environment 12

13 HIGH TEMPERATURE CORROSION DIFFUSION OF THE GASES Tube surface Oxygen O 2 Carbon C, CO, CO 2 Nitrogen N, N 2, NH 4 Sulphur S, SO 2 Molten Salts Na, K, V Cr 2 O 3 Oxides (Oxidation) Cr 23 C 6 Carbides (Carburization) CrN 2 Nitrides (Nitriding) Ni 2 S Sulphides (Sulfidation) Slag 13

14 253MA DUAL PROTECTIVE LAYER EFFECTS OF RARE EARTH METALS Second protective oxide layer SiO 2 Tube surface Oxygen O 2 Carbon C, CO, CO 2 Nitrogen N, N 2, NH 4 Protected Tube Sulphur S, SO 2 Molten Salts Na, K, V Protective Oxide layer Cr 2 O 3 * Rare Earth elements (Cerium, Lanthanum, etc.) 14

15 CORROSION RESISTANCE OXIDATION AND CARBURISATION Sandvik 253 MA has very high resistance to oxidation, especially at cyclically varying temperatures The very good properties of this grade in cyclic conditions have been achieved by addition of Rare Earth Metals (REM s) High chromium content and the addition of silicon and rare earth metals, results in a protective oxide is easily formed on the surface of Sandvik 253 MA material with good carburization resistance. Sandvik 253 MA is less prone to carburization at high temperatures in these conditions than 25Cr/ 20Ni steel and Alloy 800H 15

16 STRUCTURAL STABILITY At High Temperature Carbides precipitates due to high presence of Carbon- Brittle Sigma Phase formation Sandvik 253 MA has lower (2 to 10 times) tendency to form embrittling phases due to low chromium content in the matrix, high carbon and presence of nitrogen Sigma phase formation limited to narrow temperature range The sigma phase contains higher amount of chromium resulting in areas which are depleted and have lower corrosion resistance Results are Lower the impact strength as well corrosion resistance. 16

17 HIGH TEMPERATURE GRADES Sandvik designation ASTM TP 17 Sandvik 5R10 304H Sandvik 6R35 321H Sandvik 8R40 347H Sandvik 4C Sandvik 7RE10 310S/310H Sandvik 253MA - Sandvik 353MA - Sandvik 8RE18 309S Sandvik 31HT Alloy 800HT Sandvik 41 Alloy 825 Sandvik70 Alloy 600

18 CARBON BLACK INDUSTRY- APPLICATIONS Air pre-heater (soot & gas cooler) Oil pre-heater Scrubbers & gas cleaning units Continuous Rotary drier 18

19 OIL PREHEATER Oil is pre-heated from 150 C to 160 C by the process gas Carbon steels often fail due to precipitation of Sulphuric Acid Sanicro 28 is a good choice for tube replacement 19

20 SCRUBBERS & GAS CLEANING UNITS Condensates formed contain sulphurous or sulphuric acid of unpredictable concentrations Alloy 825 often used, Sanicro 28 can also be applied CONTINUOUS ROTARY DRIER 253MA tubes are used as pipe lifters in the drier. Operating temperature 800 C 20

21 PEOPLE MAKE IT POSSIBLE, REST IS METALLURGY 21

22 SMT.SANDVIK.COM

23 MANAB HALDER