I N D U S T R I A L A N D E N G I N E E R I N G CHEMISTRY
70 (171)
Tompkins, E. R., Harris, D. H., and Khyni, J. X., J , Am.
C'hem. Soc., 71, 2504 (1949). (172) Topp, N. E., and Pepper, K. W., Chemistry & Indzcatry, 1949, No. 1, 12. (173) Troedsson, J. S. W., Festskrift Tillagnad J. .4rvid Hedvall, 1949, 563. (174)
Updegrsff, I. XI., and Csssidy, H. G., J . Ani. Chem.. Soc., 71, 407 (1949).
~J . J , , 7th congr. ~ ~ ~~ t~ ~~A ~~~ , ,,paris, ,d ~ . ,1948, ~ 94-G. (176) Vlamis, J., Soil Sci., 67, 453 (1949). (177) Vlanlis, J..and Jenny, H., S c i e m e , 107, 549 (1948).
(175)
van ~
VOl. 42, No.' 1
Voloklwyanski, V. M., Chem. Zentr., 1947, I, 566. Walker, J. G., Chemistry & Industru, 1948, No. 44,695. Wallerstein, L., U. S. Patent 2,476,785 (1949). Weiss, D. E., Nuture, 162, 372 (1948). wikla,ndei, L., and Gieseking, J. E., Soil Sci., 66, 377 (1948). Willoox, 0. W., Sugar, 43, No. 12,27 (1948). Wi!liam% T. 1.1A d .C h h . Acta, 2, 635 (1948). Winters, J. C., and Kunin, R., IND.EKQ.CHEM.,41, 460 (1949). Wdlie, l M. R.J., , and Patnode, H. W., 23rd National Colloid Symposium, abstracts, p . 9 (1949). (187) Zowader, H., Chem. E m g . Progress, 45, 279 (1949).
(178) (179) (180) (181) (182) (183) (184) (185) (186) ~
R S C ~ I V EOctober D 12, 1949.
I ORE competitive business conditions during thc? past year caused increased attention to be given to materials handling operations and equipment. This is natural, for materials handling methods Rave not always received adequate attention. We have emerged from a long period in which emph&s was on production. Now cost-saving methods are oft,en more important than production. PIIIat,erials handling studies genemliy reveal posibilities of subst(antia1savings. Two of the fundament,als of materials hamiling mentioned by Noski ( 2 4 ) are being more generally recognized: The cost of handling is an economic waste, and if handling cannot, be eliminated, t'he frequency and distance of all handling should be minimized, as well as the use of manual effort. One evidence of the increased attention being given to materials handling is the increased literature 011 the subject. Excellent papers on t,he economics and techniques of materials handling were presented at the Third National Materials Handling Exposition a t Philadelphia, and have been published (3). Lahey ~1 some of the major trends in ina handling. LIQUID A N D GAS HANDLING
PUMPS.Several new types of pumps were announced during the gear. One is a new sanitary food process pump (6),which is designed for easy dismantling for cleaning. It is designed to meet the rigid sariit,ary and mechanical requirements imposed in food evaporation processes. A new pneumatic pump (31) requires no lubrication, has no glands or bearings, and handles, without aeration, many liquids of varying character. This pump has been designed so that the pumping head mechanism never comes in contact with the fluid being handled. This type of pump might be the answer to pumping problems involving gritty or corrosive matter. The pump operates automatically by the following method: An air-operated ejector in t'he pump head creates a vacuum and draws the liquid into the pump case. Liquid rises in the pump case until a float shuts off t,he air to the ejector and causes the air to flow into the pump case causing the liquid t o be expelled. A relatively new pump, although not one developed in the past year, is a n elbow propeller pump (38) which has been applied to the circulation of solutions from crystdlizers. I t is designed for handling large flows a t low head, and the arranpement of the pump in an elbow conserves space and reduces head loss. Taylor (36)reviews the trends in pump usage and the progress that has been made in pumps, and points out three basic pump problems: (1) getting and maintaining sufficient suchion, (2) reducing and preventing leakage, and (3)reducing cost), including
opcrating. The paper desciihes the progress being mrtde in solving these problems. A paper by Uahill (6)summarizes the advances during thr. past 10 years in pipe lint. primping equipment. This paper points out that the old time slow speed reciprocating pumps are now being replaced by advanced types of reciprocating pumps or high capacity centrifugal pumps. Stinson (34) discusses the comparative costs of m e c h a n i d vacuum pumps vcrsus steam jet ejectors. Allis Chalmeis ( I ) has issued a "Handbook for Careof Centrifugal Pumps." ComRmsoRs. The Carthage Hydrocol plant for manufactuiing gasoline from natural gas will require 24 compressors with a capacity of over 80,000 horsepower (18). The two main compressors are centrifugal units compressing 110,000 cubic feet per minute of air t o 100 pounds per square inch with a power requirement of 23,000 hp. A new semiportable high pressure compressor has bern clcsigned for laboratories, pilot plants, and wherever prwsures up to Eo00 pounds are required in relatively small volume. The unit is a four-stage compressor built entirely of steel or noncorrocii c materials (26). A new type of blower is being offered which is said to be rcmarkably efficierlt, ~ x t r e m e low l ~ in weight, and capable of oprrating at a Ion noiie 1~.vel(33). Significant litpriture on compressors has appeared during the year. Edmister and hIcGarry (13) give an accurate and rapid method of cal(w1:tting the temperature and enthalpy for isentropic compressors. Kaiawik (28) clarifies the exact meaning of polytropic efficiency. hlartinuzsi (2'3) describes the progres-i being made in both axial flow and centrifugal compressors for high capacity and high (Lfficiency. A paper by Swearingen (35) summarizes a repoit of the Elliot Company on the dekgn of srnalY centrifugal blonei?. A icport (7) in speaking of the use of compressors for high pressure states that the rnosi, marked chanpr has been the groiving UFC: of intensifiers. SOLIDS HANDLING P4LLETS A method has been developed (27) to permit the stacking of pallets containing materials of various shapes and consisteldries. Steel pipes are attached to wooden pallets to act as support columns. A means of alignment is provided by B nesting cone which fits over the end of one post to receive a cone attached to the pallet above. This method eliminates the possibility of uneven stacking, keeps the load in exact balance at all times, and transfers the load directly to the floor, so that the lower pallets are not called upon to bear the weight of the upper pallets.
January 1950
IN D U S T R I A L A N D E N G IN E E R IN G CHE MI S T R Y
71
72
INDUSTRIAL AND ENGINEERING CHEMISTRY
Vol. 42, No. 1 Equipment” by Hudson (17) has been published. MISCELLANEOUS MATERIALS HANDLING DEVICES
A new bag-flattening machine (9) eliminates air from a bag and evenly distributes the contents. The flattened bags pile easily, stay piled better, and occupy less floor space. A new bagdumping machine (16)e h i nates laborious hand dumping of bags. The machine can be designed fur any height of t a n k a n d makes a bagdumping operation very simple. A Stair Levayor has been developed (26) which is k) device for floor to floor handling of loads. It is R modified elevator which operates on Centrifugal Campressor For Carthage Hydroeol Plant at Brownsville, Tex. an incline and can be installed over existiiia stairs TRUCKS.The most notable trend in fork trucks is the great without interfering with the normal functioning of the stairs. improvement in design to provide ease of control, maneuverThis device should be useful where the cost of a conventional ability, and decreased maintenance. One nianufacturcr (1%)has elevator cannot be justified. developed a new magnetic coupling, constant-mesh transmission An unpacking machine (88)has been developed which has B that eliminates the conventional clutch and gives instant forxard series of air-actuated mechanical fingers to grasp bottles and or reverse action by fingertip control. All manufacturers have jars, and unload them automatically from their cases. Tho continued to develop rams, ohovels, rotating forks, and numerous machine is designed so that filled or partially filled cases enter at other devices to attach to the fork trucks for special purposes. one end, the containers are discharged on a continuous conveyer A typical special device of this sort is a barrel grab which will at the other end, and the empty cases are discharged to one side. The unpacker also automatically rejects odd-size or badly damlift and transport drums, and empty the contents by turning the drum upside down (10). The fork truck, with its various modificaaged case-3, over and under length, or broken bottles. tions, is becoming the most versatile and dexterous of the variour The problem of getting bulk materials out of bins and hoppers may be solved by a new aerator device (4) which injects low presmaterials handling devices. A new hand truck ( 9 ) with a caterpillar tread permits moving sure air into bulk materials through a special fabric diffuser. material up and down stairs easily and safely. The caterpillar The aerator unit is designed so that dry, finely ground materials treads distribute the load of the truck over three or more steps will not cause them to become plugged. and allow the truck to go downstairs just like n conventional The handling of materials in and out of trucks has been complicated by the difference in height which often exists between s hand truck going down a ramp. CONVEYERS.A new type of cooling conveyer ( 8 ) carries truck and a dock. Devices have been announced for the first molten chemical products on a solid stainless steel belt that is time this year to solve this problem (19). One method is a ffoatactually supported by water. It is said that this design assures ing dock which can be hydraulically adjusted to the correct truck level. Another device is a hydraulically operated platform which 100% cooling contact with the undersids of the steel belt, thus raises the truck to the dock level. These adjustment devices providing unusually high cooling capacity. Thia cooling conshould be very useful wherever hand trucks or fork trucks have to veyer belt permits molten chemicals to be poured on at one end operate between a truck and a building. Considerable savings of the conveyer and taken off continuously in strip form at the in freight handling may often be effected by the installation of opposite end. A new type of sciew conveyer has been announced (32) in adjustable docks. which both the screw and the tube revolve. The purpose of this A freight ladder is being offered (37‘)which can handle routinr and emergency flight lifting for lifting jobs that cannot be emdesign is for the handling of materials which cannot be allowed to nomically handled by lift trucks or conveyers. It is a simple accumulate inside the conveyer. It was specifically designed for device, fully portable, and easy to operate. It consists of a small the handling of bulk food products as a means of overconling platform on wheels which is lilted up an incline by an electric infestation. motor. The power-operated freight ladder carries up 250 A paper by Sadler (30) discusses various types of gas-solids pounds a t 25 feet per minute. fluidizing systems for transport. One type of gas-solids transport Often I C J ~ Scan be unitized so that they can be transported 013 has recently been developed (14 ) in which materials are conveyed light-weight disposable pallets if the cartons are glued together. through an enclosed duct in R hich fluidization is accomplighed A new machine has been devised (11)which automatically applieh by the flow of air info the material through a low perm~ability porous medium inside the duct. The duct is slightly i n c h e d n, quick-drying adhesive to the cartons in an amount sufficient to hold bhe cases together during handling, and still permit easy tnd the partially fluiaized mass flows under the influence of breaking up of the load without damage to the cases. gravity. Two papers of possible general interest are “Materials €IanA brief summarizing report (16) is given of a paper which ded i n g in Plastics Processing” by Lee (11)and a description of the scribes the method of designing pneumatic conveying systems. handin? of metallic sodium by Kaslens and Peddicord (19). The second edition of a handbook on “Convvors and RrIated I
January 1950
73
INDUSTRIAL AND ENGINEERING CHEMISTRY CITED
(20) Lahey, R. W., Chem. Erie., 56, No. 4, 167 (1949).
kee, Wis., Bull. 08X6256A. , 1320 Clark St., Racine, Wis.,
(21) Lee, J. H., Ibid., 56, No. 8,100 (1949). (22) Machine Design, 21, No. 6 , 148 (1949). (23) Martinuzzi, P. F., Chem. Eng., 56, No. 5, 130 (1949). (24) Moski, B. A,, Jr., Factwy Management & Maintenance, 107,
(3) Am. Soc. Mech. Eng., Proceedings of Materials Handling Conference, Philadelphia, 1949. (4) Bin-Dicator ,Po., 13946 Kercheval Ave., Detroit 15, Mich., “Bin-Flo. (5) Byron Jackson Co., P.O. Box 2017 Terminal Annex, Los Angeles, Calif., bulletin. (6) Cahill, J. H., Oil & Gas J.,48, No. 5,93 (1949). (7) Chem. Eng., 56, No. 8, 116 (1949). (8) Chem. Eng. News, 27,47 (1949). (9) Ibid., p. 642. (10) Ibid.,p. 1684. (11) Chem. Processing Preview, 12, No. 9, 31 (1949). (12) Clark Equipment Co., Battle Creek, Mich., Bull. TC-24. {13) Edmister, W. C., and McGarry, R. J., C h m . Eng. Progress, 45, No. 7,421 (1949). (14) Fuller Co., Catasauqua, Pa., BUZZ.F-H-1. (15) Heating, Ventilating Air Conditioning, 2 (16) House, Jacob & Sons, 52 St. Paul St numbered bulletin on bag dumping machine. (17) Hudson, W. G., “Conveyors and Related Equipment,” 2nd ed., New York, John Wiley &Sons, 1949. (18) Karassik, I. J., Chem. Eng., 56, No. 8 , 1 119) Kastens, M. L., and Peddicord, H., IND (1949).
Upon COURTESY Of
EQUIPMENT AND ACCESSORIES
FOR HANDLIN
RUMS
( (
(28)
(29) (30) (31) (32)
, Conn., bulletin on semiportable kson Blvd., Chicago 4, Ill., unnumbered bulletin on tiering methods for pallets. Power Generation, 53, No. 8 , 61 (1949). Rowe Methods, Inc., 1743 East 25th St., Cleveland 14, Ohio, unnumbered bulletin on adjustable truck docks. Sadler, A. M., Chem. Eng., 56, No. 6,110 (1949). ng Co., Philadelphia, Pa., Bull. 49-6-190- J1. S Corp., 700 Hoffman St., Hammond, Ind.. S -700-2.
(33) Standardaire Stoker Co., Inc., 370 Lexington Ave., New York 17, N. Y., Publ. 84. (34) Stinson, L. S., Powerfaz (Elliot Co.), summer issue, 116 (1949). (35) Swearingen, J. S., “Design of Small Centrifugal Blowers,” idge, Tenn., Atomic Energy Commission, 1949. g, Chem. Eng., 56, No. 5 , 128 (1949). uipment Go., Inc., 45 River Rd., Nutley 10, N. J.. ed bulletin showing Tipp freight ladder. Pump & Machinery Co.. Harrison, N. J., Bull. W-35O-Bl5. RECEIVED October 17, 1949.
