MATERIALS HANDLING 141rE
RICHARD L. SPEAKER
ETANDARD CONVEYOR CO., NORTH SI. PAUL 9, MINN. Materials bndling in 1951 was again marked with innorotions end revirion in 4 t t . h menb for motorized IiH devlcu. Attention in the conveyor lndutry wos given mom to finding new oppliution for exidng mnveyon n t h a tlnn to p n m U n g new equipment Monorsll equipment manufoctum featured on outomatic diswkh unin and an overhead crone for use in worehourn.
m a t s and attsohments that perform
mom accurately than ever the functiom of human handa and musclaa. A new artillery shell clamp (7)cm h e used i n t e r c h a n g e a b l y w i t h
B
ECAUSE the aubjeot ofhandling of solid materials do= not seem to lend itaelf readily to theoretical scientific aoslysis, published articles deal moatly with equipment impnovement and specific cam histories. Furthermore it appean that there is B tendency t o concentrate the n o m in this field to two widely distributed monthlies dealing exclusively with the subject ( I t , 16). Bibliographies of srticles therein would be repetitive 90 the reader is referred t o them for B study of esse histories oi interesting installations. In spite of the apparent lack of scientific interest in the subject, there is certainly no lack of interest in it8 practical a p p l i c a t i o n s . M a t e r i a l s handling has become the frontier of industrial cost-reduction programs, B fact which is verified by the increase in volume of businew hy materials handling equipment manufacturers from $25O,ooO,ooOio 1948 to an estimated S1,125,000,oW in 1951. Mnnufseturers of motorized lift trucks continue to pac.e the industry's technological advance with improve-
Btandard pallet forks. I t grmpa, lifta, and mtates ahells and plaow them in presaes, racks, or in any other place they may be needed. Other attachments for fork trucks, some of which are not new,
Automatic Stocker and Segregstor System
Coliapdble Pottable Belt Conveyor Looding Bogged Gain Into Freight Car
ea
include bale clsmps, ramn, cranes and boom, shovels and pitchforks, and rotating devices. Most manufacturers now incorporate s nide-shifting device for precke location of the pallet without the necessity of jockeying the truck. Many other innovations in trucks have appeared, introducing i m p r o v e m e n t s i n d r i v e mechanism, controls, a n d in features afIeoting operator comfort. Larger and larger trucks are being introduoed to meet special dem n d s , and thia y e a trucks baving oapaeities of M,oW and 1W.ooO pounda have been put into use (IO, eS). One very pmmiaing improvement for gae-powered fork trucks is a catalytic m a e r element (19) which clln he attached to any standard fork truck. It Donverte the harmful mooodde fumw to
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INDUSTRIAL A N D ENGINEERING CHEMISTRY
Val. 44, No. 1
h v e developed wire-mesh containem for the storage and shipment of irregw lsrly Bhaped materida, such as eastings. Theae containers fold up to &out one-quarter size when empty, cutting down return shipping costa. Expendable pallets (I) of wood and paper continue to improve in quality ennd are finding an inmensing market. A helpful paper showing a method of analyzing the economics of expendable pallets baa been published (2). Fourway entry pallets are gaining populnrity, especially ie the 40 X 48 inch sive which can be stored two abreast 40 inches wide in trucks and two ahremt, 4R inches wide i n freight ears. CONVEYORS
Perhpa because they represent one i r l the older forms of mechanized handling equipment, conveyor manufacturers have not presented many basic. i n n o v a t i o n s during the past year This does not mean the i a duelry has been dormant but rather that attention has been Concentrated on finding new applications for existing types. In the package handling Ram-Tyue Porn Truck lor Handling Steel Coils Up to 40,OOO Pounds field emphasis b e been placed on urging owtomers t o use a strict cngineering approach to condioxide, thns elimiinstimg a strong objection, on the grounds of veyor layouts in elristing fsoilities 8 s well as in new plsnt ssfety, to the relatively cheap gas-powered unite. layouts. dsta which mu& be supplied by the weer in order Ir, a large plant industrial trucks often mnst tmvel long disto properly evalwte the value of installing conveyors includea tsncee to deliver a load and then return to the starting point production data, futLwe plans, and time studies of existing us. proemotv-handed . _ . to get new orders. If each demrtrnent has its own posed methods. This latter point has ufteri proved a atunhliug trueks, idle msel&e h a m are inevitable. The installation of a black io engineering ainsIyee8. because of the difficultyof eecuriw, centralized intrsplaot fmight department, coupled with a taxicab systemof trs~wsyrrcdiobetlseeoadispateherandthetmckopertjme-studydataonpropo*edoperstiona A new sbort-cut method for time study of yreaent and proposed stor, has done an outstsndiug job in reducing idle time, arcording operstionB is ofiered by Multier (18) who oEem the me of prede to Moore ( 1 7 ) . tarmined motion times for handling operations. The author has Developnient of high atmogth fiberboards has lifted the Pulcompiled reliable data on the time required to perform doze- uf Pse system out of the experimental stage. Tllls syskrn iovorpobaaio movements, and by adding up the figures which apply 10 a rstesa clamping device on the tmrk which "bites" a thin fiberpalproposed operation, the ressarcher arrives at a reawnable figure let and pulls it into the forks. A pantographic pwher plate upon which to baae probable future costa. These data not only dide~thelodedpalletofithetruckonto theatomgepile(9). preclude the ueceRsity for timffoosumine dudiw on r\ieling Another company has developed a forklem pallet in which 'ISinch lhiek uallets with two thin verti.
INDUSTRIAL AND ENGIWEERING CHEMISTRY
67
the mammoth Interlske Byetem proposed to span Ohio haa been
aompleted,althoughitisstillfarfromcertainthatthepmjeetwill
EDyllTu" B m X a IXD".III,II
1nwx
00
Artillery Shell Clamp Attachment on Motocizrd Lift Truck lnud i h o n horimnl.1 poiWm d demo
operations, hut also for the first time offer a haeis for computing expected savings on a hypothetical system. Perhapa its RCCUraCy in open to question, hut a t least i t offers some banis for figurng. One of the problems of mechanized materials handling which han received considerable attention recently is that of combining the advantages of a conveyorized production line with the equally important dvnntagea of palletized handling in the storage area. Two leading conveyor manufactwen (8, 14) have developed automatic pallet loaders on which CRI'hna nre delivered directly from B conventional conveyor system onto pallets in a predetermined pttem, sfter which the Bled pallets are ejected onto a platform from which they can he removed by fork trucks. A t the present stage of development automatic pallet loaders are quite expensive, hut Lsnaon ( 1 1 ) suggests an engineering formula fmm which the economic justilkation can he determined for R partiaular set of conditions. Another mnnufailcturer (IS) ha6 attacked this same problem from a somewhat dserent standpoint. Realizing the space di8advantage inherent in the use of palletized storage, an automatir atacker and aegregator has been designed t o aid in the mechanized ~toregeof unpalletized containers. This unit will accept a mixed group of cartons frome. conveyor system, ano first segregate t.hem into groups of similar units. This segregation can he made automatically in casea where the oartons are of different sires or colors, so that electric eyes can he used. Otherwise, an operator is Rtationed at the machine to operste the necessary switches. After segregation, the mschine antometirally stacks the carton? in each group in n. single stack of predetermined height. When thir height has heen reached the pile is ejected onto a n adjacent platformfromwhiehaclnmpty~ieforktaurk e m t,rannferonsor mwr stacks a t a time to storage. In hoth spproaches to the prohlem, manual handling has been completely eliminated. It would seem that if eventual shipment is t o go forward on pallets, the first approach would he more practical; if pnlletized shipment is not possible, the latter approach should he coasidered, especially in view of the fact that a complementary unit i s available which will nnstack the cartons and feed them hack onto a conveyor system running directly in the cars. A nafety-type live roller conveyor has recently been announced for u8e on assembly lines (gl). By an ingenious combination of direct and friction drive on each roller, individual rollers stop if fingers get caught between them, while the rest of the conveyor continues to operate. It alno allows individual packages to he held stationary for filling, sealing, or labeling, without stopping the entire conveyor. ThB use of conveyor belts for long distance transmiasion of hulk materials continues to show economics1 resulte. Engineering for
proceed. Several rubber companies have announced high tensile strength belting made by molding rubber over steel cables instead of cotton duckcommonly used. Thesebelts incream the maximum dis tame between pulleys and thus cut down the number of transfer points in a long system. A p t deal of interat is being &own in the application of Fiherglaa-Bilicone rubber combination8 in belting for resistaoce to heat, but at the present stage of develop ment, cost and availability of the materials is a restraking fm tar, and consequently commercial production ban not beAnother novel method ban been proposed for conveying coal over long distances. The cod would he pulverized and added to water to form a BIUT which would he pumped through pipe linea, then hriquetted and dried for delivery to the consumer. No instailations have yet been recorded. Although not a new dwdoDment. little note been a v e n previouely to 8 wrew conveyo; on the ursrket in which bo& the jstket and the screw revolve. The revolving jacket ensurea that 811 material continues to move through the conveyor, thus pr+ vrnting euntaniiuatioo or spoil>rge. M O N O R A I L S AND HOISTS
Overhesd mouorail and hoist equipment 6ndn its major applicstiou in t h o heavy equipment manufacturing industry. The extreme 8pzu.e rrquiwd tu move IJUlky i t e m , such 88 sheet aieel, yipp, twd large fabricated atrurturea dirrctx the useol spaceabove
Fork-Truck Device that Hsndln Unit Loads without U= of
bnventiolui P4ddk1
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Vol. 44, No. 1
INDUSTRIAL AND ENGINEERING CHEMISTRY
manufacturer claims t h a t narrower aides permit up t o 50% increase in usable floor space. A self-contained battery-powered electric tractor drives a new overhead monorail train ( 8 ) . The low initial cost resulting from elimination of electrical wiring throughout the system should offer a decided economic advantage in many cases. LITERATURE CITED
(1) Acme Pallet Co., 16 Park Row, New York 7, N. Y., bulletin
011
expendable wood pallets. (2) Addison-Semmes Corp., 1800 Thurston Ave., Racine, Wis., “Savings in the Use of Expendable Pallets.” (3) Alvey Conveyor Mfg. Co., 9303 Olive St. Rd., St. Louis 24,Mo., bulletin. (4) American MonoRail Co., 13107 Athens Ave., Cleveland 7, Ohio, bulletin. (5) A. 0. Smith Corp., 3533 N. 27th St., Milwaukee, Wis., movies on handling techniques in heavy industry. (6) Automatic Transportation Co., Div. of Yale & T o m e Mfg. Co.. 153 West 87th St., Chicago 20,Ill., release on forkless pallet system. (7) Baker Radang Co., Industrial Truck Div., Cleveland 2, Ohio., bulletin. (8) Bloom Systems, Inc., advertising release on battery-powered monorail tractor. (9) Clark Equipment Co., Industrial Truck Div., Battle Creek, Mich., Clark Pictorial News,9,No. 1, 22 (1951). (10)Elwell Parker Electric Co., 4069 St. Clair Ave., Cleveland 3, Ohio, release on heavy duty fork truck. (11) Fbw, 5, No. 13,38 (1960). (12) Ibid., 6,all numbers (1961). (13) Food Machinery & Chemical Corp., Packing Equipment Div.. Riverside, Calif., bulletin on automatic box segregation and stacker. (14) k m s o n Corp., Syracuse 1, N. Y., bulletin on automatic pallet loader. (16) Materials Handling Labs., Inc., 796 Boyleaton St., Boston 16, Mass., bulletin. (16) M a d m Materials Handling, 6,all numbers (1951). (17)Ibid., 6,No. 6,66 (1951). (18) Multier, “Advanced Plant Layout.” (19) Oxy-Catalyst Mfg. Co.,392 West Lancaster Ave., Wayne, Pa., bulletin on catalytic muffler attachment. (20) Pittsburgh Steel Products Co., P. 0. Box 118,Pittsburgh 30,Pa.,
CWRTESY AUTOMATIC TRANIIPORATION 00.
Forkless Pallet Part of New Handling System
other machinery and obstructions. Some very interesting movies on handling procedures in the manufacture of pipe, auto frames, and water heaters are available for rental (6). One manufacturer of monorail equipment showed an automatic dispatch carrier a t t h e materials handling show in Chicago (4). By remote control this carrier can accomplish such feats a8 carrying a load of core sand t o a predetermined molding station, dumping the sand, and returning t o the muller without further atten-
tion. Another innovation introduced at the show was an automatic warehouse in which the handling equipment consisted of a n overhead crane system. The crane spanned the complete width of the building, and in place of the conventional cab on the crane was a pivoted cab t o which forks were attached, and in which the operator sat. In other words, a fork lift truck has been converted into a “fork lift crane.” By moving the fork lift off the floor the
Bull. MH15. (21) Standard Conveyor Go., North St. Paul, Minn., bulletin on
safety-tgpe live roller.
(22) Union Steel Products Co., Albion, Mich., bulletin. (23) Yale & T o m e Mfg. Co., Roosevelt Blvd. & Haldeman Ave.,
Philadelphia 16,-Pa., release on heavy duty ram-type fork truck.
REWIVEDOctober 10, 1881.
IXING J. HENRY RUSHTON’ ILLINOIS INSTITUTE OF TECHNOLOGY, C H I C A G O , ILL.
Literature on the fluid mechanics of mixing this year included data on the spread of a jet and the mixing entailed. A technique is described for accurate scale-up of mixing equipment involving heat and mass transfer requirements. In the field of heat transfer a report on coefficients for kettles with jackets and coils rupplemenb present datal new information has appeared on heat transfer in the mixing of viscous materials. Experimental work on a first-order continuous Row reaction was carried out to give results applicable to commercial equipment. Articles werealso published on the mixing of polymers and highly viscous materials, the effect of agitation produced b y a flowing stream on the growth of crystals, and the mixing of gases in fluidized beds.
c
ONSIDERABLE attention has been given t o tho fundsmental fluid mechanics of mixing. During t h e year two articles appeared which give more information on the r e b
tiona between m a a ~transfer, momentum transfer, mixing, and the 1
Also director of researoh, Mixing Equipment Co., Rooheeter, N. Y.
physical properties of fluids. Foratall and Shapiro (6)have summarized a large amount of work of others relating t o the mechanics of mixing of jets of fluids. Almost all t h e work pertains t o gases, but the analogies and extension of principles to liquids are evident and of considerable importance. They also report on their own experimental work wherein they studied the mixing of a circular jet of gaa in an annular coaxial stream of gas, all energy being supplied by the jet and coaxial stream. Helium was wed as B tracer gaa and the mixing region waa mapped with respect to both momentum
