Corrosion Chart

Corrosion Chart published as annual supplement to December issue of Chem. Processing... 

Swandby, R.K. Corrosion Charts Guides to Materials Selection, Chemical Engineering, Nov. 12, 1962, p. 186. 

Corrosion rates are expressed in terms of inches per year of surface wastage and are used to provide a corrosion allowance in the design thickness of equipment such as vessels and pipes. Operators will often use data based on historical experience from plant operations to aid them in determining appropriate corrosion allowances. Alternatively, corrosion charts are widely available that give corrosion rates for many combinations of materials of construction and process fluids, and normally a range of values will be provided for various process temperatures. In some instances, particularly where there is a mixture of chemicals present, appropriate data may not exist and corrosion tests may be necessary in order to determine the suitability of equipment. Operators should be able to demonstrate the use of corrosion allowances in equipment specification and design. The sources of data used should be traceable. 

Hoke Corrosion Chart, Hoke Inc., I Tenakill Park, Cresskiil, NJ. A compact tabulation for common metals and plastics. 

System for the Evaluation of Pitting Corrosion-Chart Method... 

Corrosion of metals and alloys— Removal of corrosion products from corrosion test specimens Metals and alloys— Atmospheric corrosion testing—General requirements for field tests Anodized aluminium and aluminium alloys—Rating system for the evaluation of pitting corrosion—Chart method... 

TRENT ALLOY Characteristics Corrosion Chart A = average, G = good, E = excellent, NR = not recommended, X = call for specific data CORROSION RESISTANCE ... 

Corrosion charts for specific alkaline solutions are presented below. The charts for sodium hydroxide and sodium carbonate may be used as a general guideline for all hydroxide and carbonate solutions, for example, KOH and K2CO3. For hydroxide concentrations greater than 4 wt % (pH 14), the maximum allowable temperatures for a rate of 0.2 mm/yr are 66 C at 10%, 60°C at 20%, 57 C at 30%. 

Corrosion charts courtesy of the Nooter Corporation, St. Louis, Mo. 

With a simple experimental technique, iso-corrosion charts for important alloys in specific environments can be prepared. The iso-corrosion chart for titanium in H2SO4 is shown in Figure 9.11b. 

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