Technical

Info
Conversion Factors
Corrosion Resistance Data
Equivalents of Std Wire Gauges
Fractions of Inches
Hardness Comparison Table
Nominal Composition of SS
Pipe Working Pressures
Useful Conversion Formulae
Theoretical Mass Calculation

Corrosion Resistance Data

R - The material is RESISTANT to the named chemical up to the temperature shown, subject to limitations indicated by the footnotes at the bottom of the page.
NR - The material is NOT RECOMMENDED
ND - NO DATA is available

Chemical Temp °C
Stainless Steel 18/8 (304, 304L & 321) Molybdenum Stainless Steel (316 & 316L) Duplex Ferritic-Austenitic Stainless Steel 3CR12
Chemical 20 60 100 20 60 100 20 60 100 20 60 100
Aldyhydes R1 R1 R1 R1 R1 R1 R1 R1 R1 R1 R1 R1
Acetic Acid (10%) R R R R R R R R R R R ND
Acetic Acid (glac & anh) R R NR R R R R R NR ND ND ND
Acetic Anhydride R2 NR NR R R NR R R R R2 NR ND
Acetylene R R R R R R R R R R ND ND
Acid Fumes R3 R3 R3 R3 R3 R3 R4 NR NR NR NR NR
Alcohols R R R R R R R R R R R R
Alphatic Esters R R R R R R R R R R ND ND
Alkyl Chlorides R5 R5 R5 R5R R5 R5 R R R R5 ND ND
Alum R R6 NR R R1 NR R R NR ND ND ND
Ammonia R R R R R R R R R R R R
Amyl Acetate R R R R R R R R R R R R
Aniline R R R R R R R R R R R R
Antimony Trichloride R5 NR NR R5 R5 NR R R NR NR NR NR
Aromatic Solvents R R R R R R R R R R R R
Atmospheric: Industrial R7 ND ND R ND ND R ND ND R7 ND ND
Atmospheric: Marine R7 ND ND R ND ND R ND ND R7 ND ND
Atmospheric: Rural R ND ND R ND ND R ND ND R7 ND ND
Ascorbic Acid R1 R1 R1 R R R R R R R1 ND ND
Benzoic Acid R R R R R R R R R R R R
Boric Acid R R R R R R R R R R R R
Brines, Saturated R8 NR NR R8 NR NR R R R NR NR NR
Bromide (k) soln R9 NR NR R9 R9 R9 R ND ND NR NR NR
Bromide (+ aqu) NR NR NR NR NR NR NR NR NR NR NR NR
Butyl Acetate R R R R R R R R R R R R
Calcium Chloride NR NR NR R8 NR NR R10 R10 R10 NR NR NR
Carbon Disulphide R R ND R R ND R R R R R R
Carbonic Acid R R R R R R R R R R R9 NR
Carbon Tetrachloride R R R R R R R R R R R R
Caustic Soda & Potash R R R6 R R R6 R6 R6 ND ND R6 R6
Cellulose Paint R R R R R R R R R R R R
Chlorates of Na, K, Ba R1 R1 R1 R1 R1 R1 R R R ND ND ND
Chlorine, Dry R R R R R R R R ND ND ND ND
Chlorine, Wet NR NR NR NR NR NR NR NR NR NR NR NR
Chlorides of Na, K, Mg, Ca, Ni, HN4 R10 NR NR R9 R11 R11 R R ND R5 NR NR
Chlorosulphonic Acid NR NR NR R10 NR NR ND ND ND ND ND ND
Chromic Acid (80%) NR NR NR NR NR NR NR NR NR NR NR NR
Citric Acid R6 R6 R6 R R R6 R R R NR NR NR
Cresylic Acids (50%) R R R R R R R R R R R R
Detergents, Synthetic R R R R R R R R R R R R
Emulsifiers (all conc) R R R R R R R R R ND ND ND
Esters & Ethers R R R R R R R R R R R R
Fatty Acids (> C6) R R R R R R R R R R R R
Ferritic Chloride NR NR NR NR NR NR NR NR NR NR NR NR
Fluorinated Refrigerants, Aerosols eg Freon R5 R R R5 R R R R R R5 R NR
Fluorine, Dry R ND ND R ND ND R R ND ND ND ND
Formic Acid R NR NR R R ND R R ND NR NR NR
Fruit Juices R12 R R R R R R R R R13 NR NR
Gelatine R1 R R R1 R R R R R R1 R1 ND
Glycols R R R R R R R R R R R R
Hydrobromic Acid (50%) NR NR ND NR NR ND NR NR ND NR NR NR
Hydrochloric Acid (10%) NR NR NR NR NR NR NR NR ND NR NR NR
Hydrochloric Acid (conc) NR NR NR NR NR NR NR NR ND NR NR NR
Hydrocyanic Acid R R ND R R ND R R ND R ND ND
Hydrofluoric Acid NR NR NR NR NR NR NR NR NR NR NR NR
Hydrogen Peroxide (30%) R R R R R R R R R R R ND
Hydrogen Sulphide R5 R5 R5 R5 R5 R5 R5 R5 R5 R5 R5 R5
Hypochlorite (Na 12-14%) R14 NR NR R14 NR ND R14 ND ND R14 ND ND
Ketones R R R R R R R R R R ND ND
Lactic Acid (100%) R NR NR R R NR R R ND NR NR NR
Lead Acetate R R R R R R R R R R R R6
Lead Perchlorate R1 R1 R1 R R1 ND ND ND ND NR NR NR
Lime (CaO) R R R R R R R R R R R R
Manganate, Potassium (K) R R R R R R R ND ND R6 ND ND
Meat Juices R R ND R R ND R R R R7 NR NR
Mercuric Chloride NR NR NR NR NR NR R R R NR NR NR
Milk and Milk Products R R R R R R R R R R NR NR
Molasses R R R R R R R R R R R R
Monoethanolamine R R R R R R R R R R R R
Naphthalene R R R R R R R R R R R R
Nitrates of Na, K, NH3, R R R R R R R R R R R R
Nitric Acid (<25%) R R R R R R R R R R R15 NR
Nitric Acid (50%) R R R R R R R R R R R15 NR
Nitric Acid (90%) R NR NR R NR NR R NR ND R NR NR
Nitric Acid, Fuming R R2 NR R R2 NR R NR NR ND ND ND
Oil, Diesel, Petroleum R R R R R R R R ND R R R
Oils, Essential R R R R R R R R R R R R
Oil, Lube with Aromatic Acids R R R R R R R R R R R R
Oils, Vegetables & Animal R R R R R R R R R R R R
Oxalic Acid R6 NR NR R6 R16 NR R R R NR NR NR
Perchloric Acid NR NR NR NR NR NR NR NR NR NR NR NR
Phenol R R R R R R R R R R R R
Phosphoric Acid (20%) R R R R R R R R R NR NR NR
Phosphoric Acid (50%) R R NR R R R R R R NR NR NR
Phosphoric Acid (95%) R R NR R R NR R17 R17 R17 NR NR NR
Phosphorous pentoxide R R R5 R R R5 R R R ND ND ND
Pyridine R R R R R R R R R R R R
Sea Water R9 NR NR R9 NR NR R R R NR NR NR
Silicic Acid R R R R R R R R R R R R
Sodium Peroxide R16 NR NR R6 R16 R16 R R R NR NR NR
Sodium Silicate R R R R R R R R R R R R
Sodium Sulphide R R NR R R NR R R NR R6 R6 NR
Starch R R R R R R R R R R R R
Sugar, Syrup, Jam R12 R R R R R R R R R12 R12 R12
Sulphamic Acid R18 NR NR R R19 NR R R NR NR NR NR
Sulphates (Na, K, Mg, Ca, R R R R R R R R R R R R
Sulphates R R R R R R R R R NR NR NR
Sulphur Dioxide, Dry R R R R R R R R R R R R
Sulphur Dioxide, Wet R NR NR R R NR R R NR NR NR NR
Sulphur Dioxide, ag soln (96%) R NR NR R R R R R R NR NR NR
Sulphur Trioxide NR NR NR R5 R5 R5 R5 R5 R5 NR NR NR
Sulphuric Acid (>50%) NR NR NR R16 NR NR R R NR NR NR NR
Sulphuric Acid (70%) NR NR NR NR NR NR NR NR NR NR NR NR
Sulphuric Acid (95%) R NR NR R NR NR R NR NR R15 NR NR
Sulphuric Acid, Fuming R R2 NR R R NR R R NR R2 R2 NR
Tannic Acid (10%) R R R R R R R R R R R NR
Tartaric Acid R R R R R R R R R NR NR NR
Trichloroethylene R5 R5 R5 R5 R5 R5 R5 R5 R5 R5 R5 R5
Urea (30%) R R R R R R R R R R R R
Water, Pure R R R R R R R R R R R R
Yeast R R R R R R R R R R R R

PITTING & CREVICE CORROSION RESISTANCE

Exposure in chloride containing media can result in localised corrosion. In order of increasing resistance to localised corrosion: 3CR12 <304L <316L

AVOIDING PITTING AND CREVICE CORROSION

CONDITIONS

  • Design vessels for complete drainage - avoid sharp corners and stagnant areas.
  • Close crevices and lap joints by continuous welding.
  • Remove solids in suspension. Prevent sedimentation. Ensure continuous agitation and adequate flow rates.
  • Use compressive non-absorbent gaskets or inert sealing compounds.
  • Ensure non-impairment of passive surface. Repair/restore any affected areas.

NOTES

  1. Not if chlorides present
  2. Limited data
  3. Depends upon the acid
  4. Dry acid fumes, attack may occur if moisture builds up
  5. Anhydrous
  6. Depends upon concentration
  7. May discolour with time
  8. In strong solutions only when inhibited
  9. Pitting possible in stagnant conditions
  10. Possibility of pitting
  11. May cause stress corrosion cracking
  12. When free of SO2
  13. May cause contamination of product
  14. Ddilute hypochlorites can be used to sterilise some stainless steel with extreme care
  15. General corrosion may become excessive
  16. 10%
  17. On the absence of impurities
  18. Dilute
  19. Some attack at high temperatures