4 y 2 " DIAl THERMOMETERS
MANUFACTURERS OF STANDARD VESSELS (.A» identified in manufacturer's catalog) Abbe Dispersall mixer Standard mix tanks Rubber cement processor, paste mixer, grease proc essor, and standard mix tanks Denver Equipment Co. Super-Agitator and Conditioner Glascote Co. Glass-lined reactors International Engineering, Inc. Type Ο standard mixing tanks Morehouse-Cowles, Inc. Standard dissolver tanks Patterson Foundry and Machine Co. Jet mill, standardized liquid mixers, dissolvers The Pfaudler Co. Glass-lined reactors Struthers Wells Corp. Rubber cement mixer—mixing tanks and auto claves Turbo-Mixer Division, General Dissolvers, gas absorbers, and three-stage turboAmerican Transportation Corp. treater.
Made in 3 types to suit any requirements. Rigid stem, wall or flush m o u n t e d , 11 inches of scale read ing. Interchangeable with standard indus trial separable sock e t s . Stem c a n be placed at any angle and case can be ro tated to any readable position.
PALMER
SSSS MERCURY ACTUATED
RECORDING THERMOMETERS
Twelve inch die-cast a l u m i n u m case w i t h black or white wrinkle or satin finish. Single or multiple pen con struction. Electric or spring wound clock, 24 hour or 7 Day Rev olution. Flexible Ar mor and bulb of stain less steel. Ranges —40 + 950°F or Equivalent in °C.
INDUSTRIAL THERMOMETERS Red-Reading Mercury —Extruded brass case — chrome f i n i s h . Ranges —40 + 950°F or Equivalent in °C.
RED-READING MERCURY LABORATORY THERMOMETERS Thoroughly annealed for permanent accu racy. Complete l i n e A.S.T.M. and fractional division types. WRITE FOR CATALOG INFORMATION
PALMER THERMOMETERS, C . n c i n n o h 12 Oh.ο · M E I . o i .
INC. 1500
Abbe Engineering Co. Alsop Engineering Corp. Chemineer, Inc.
Materials of Construction
Selection of the material of con struction of an agitator must take into consideration the factors of strength, resistance to chemical cor rosion, resistance to wear, and, of course, price. All of these factors combined will indicate the cost of the agitator during its operating life. The manufacturers of agitators have listed as materials of construction essentially all metals and alloys which can be cast and fabricated. These include: Aluminum Bronze Cast iron Hastelloys Monel Nickel Steel
Stainless steels Titanium Steel clad with various metals Lead-covered steel Rubber-covered steel Glass-lined steel Plastic and plastic cov ered steel
The agitator shaft must not only have adequate chemical resistance, but it must have strength and rigidity to run without undue distor tion under all conditions of load. Whenever it is uneconomical or im practical to use a solid shaft, a clad shaft is often the best selection. Lead, rubber, and more recently some of the plastics are used for chemical protection over a steel or stainless steel shaft. Where the shaft is subj'ect to wear at the stuffing box, particularly when the shaft is soft like nickel, a sleeve of Hastelloy or other hardened metal is placed over the shaft at the point of wear. The agitator impeller often is sub jected to more abrasive wear than chemical attack, and, therefore, wear life of the impeller is an important consideration. Propellers are stocked by most manufacturers in stainless steels, but are available in all metals and alloys which can be cast. Tur bine-type impellers are both cast and fabricated and are available in all
common metals and alloys. Many of the fabricated turbines have re movable blades which can be re placed inexpensively after deteriora tion from chemicals and abrasives. For the most severe conditions of chemical corrosion the glass-lined steel equipment made by the Pfaud ler Co. and the Glascote Co. is avail able. Because of problems of coating steel with glass, this equipment does not have the variety of impeller shapes which are available in metal. Heat treatment of agitator shafts and impellers should be considered for the best chemical resistance and the maximum freedom from fatigue failure. Acknowledgment
The authors express their appreci ation to the manufacturers of fluid mixing equipment, who supplied data and pictures of their equipment for use in this article. References (1) Brumagin, I. S., Chetn. Met. Eng. 53, 110-14 (1956). (2) Lyons, E. J., Chetn. Eng. Progr. 44, No. 5, 341-6 (1948). (3) Lyons, E. J., Parker, N . H., Chcm. Eng. Progr. (December 1954). (4) Perry, J. H., "Chemical Engineers' H a n d b o o k , " 3rd éd., M c G r a w Hill, New York, 1900. (5) Quillen, G. S., Chetn. Eng. 6 1 , 178-224 (1954). (6) Riegel, E. R., "Chemical Process Machinery," 2nd éd., Reinhold, New York, 1953. (7) Rushton, J. H . , Can. Chem. Process Inds. 30, 55-61 (1946). (8) Rushton, J. H., Chem. Eng. Progr. 47, No. 9, 485-8 (1951). (9)
(10) (11) (12) (13) (14)
R u s h t o n , J. H.,
I N D . E N G . C H E M . 44,
2931 (1952). Rushton, J. H., Petroleum Refiner 33, No. 8, 101-7 (1954). Rushton, J. H., Costich, E. W., Everett, H . J., Chem. Eng. Progr. 46, 395-404, 467-76 (1950). Rushton, J. H., Oldshue, J. Y., Chem. Eng. Progr. Symposium Ser. 49, Nos. 4 and 5 (1953). Sacks, J. P., Rushton, J. H . , Chem. Eng. Progr. 50, No. 12, 597-603 (1954). Weber, A. P., Chem. Eng. 60, No. 10, 183-7 (1953).
Circle No. 52 A on Readers' Service Card, page 135 A
52 A
INDUSTRIAL AND ENGINEERING
CHEMISTRY For further information, circle numbers 53 A-1, 53 A-2, 53 A-3 on Readers' Service Card, page 135 A ·
