Materials Handling an
[I/=-unit
Operations Review
by J. R. ARWOOD, Union Carbide Plastics Co., New York, N Y . R. W. WESSON, Union Carbide Chemicals Co., New York, N . Y
While obsolescence cannot be eliminated, its effect can be minimized by systems plannina il
THE surge in business predicted in the last review (March 1959) has exceeded the expectations of most economists and businessmen. T h e increased profit margins reported by firms both large and small have been astounding, and certainly a just share of these new profit dollars has resulted from an emphasis in the area of materials handling. T h e challenge placed on the materials handling engineer has been met head-on. Growth in the areas of analysis technique, cost standardization, and design for efficiency have resulted in a new surge in the materials handling field. Equipment manufacturers have developed new items and modified the “stock in trade” line around factors based on sound engineering principles. There has been a change to the “design for function” technique as opposed to the “design for sales” approach. Materials handling is becoming a science controlled by competent engineers and ceases to be the green pasture of hardware salesmen. Management no longer accepts a justification for equipment acquisition merely because the return on investment is satisfactory. Today it is seeking the best solution that can be obtained for a problem. For the best allocation of capital dollars, which will tend more and more to be limited. handling systems must be designed for needs further in the future than past theories have dictated. While costly obsolescence cannot be eliminated, its effect can be minimized by “systems planning.” Good engineering dictates an evaluation between growth needs and immediate capital investment, and keeping these factors in balance is no simple job. Materials handling must be controlled with a firm hand by those in authority lest its enthusiasm either die or flounder from lack of guidance. Theory and Training The College-Industry Committee on Materials Handling Education (7) announced that its first conveyor film strip, available early this year, will be an introduction to the basic fundamen-
tals of conveyors. I t is mainly concerned with unit handling conveyors, with a brief treatment on handling bulk materials. T h e committee also reports good progress on the preparation of a teaching outline and guide for a complete course in industrial materials handling. T h e outline should serve as an excellent guide and teaching aid for instructors of extension school courses in material handling, as well as full-time professors of industrial material handling subjects. T h e fact that handling, packaging, and distribution have passed beyond the stage of management acceptance was indicated when the American Management Association (7) recently held its first conference on distribution management. Long in gaining top management recognition, the distribution function received a thorough review from its organizational importance and effectiveness to operational efficiency and economical functions. All the conference papers will be published in Distribution Age (6). A revision of the American Standard Safety Code for Powered Industrial Trucks has recently been approved by the American Standards Association (2). The revision includes a new appendix on stability tests which describe the construction and use of a new tilting platform test device for industrial trucks. Another standard just published, intended to help solve a problem that has faced most industries using lift trucks, provides for 11 standard pallet sizes.
Industrial Trucks A mobile crane boom truck has been equipped to handle Sealdbins, offering vrrsatility to a rigging and maintenance unit. Because few users of Sealdbins have need for continuous use of the truck in handling containers, its availability for other uses eliminates the need for renting rigging cranes. This container handling device is designed to permit a one-man operation without leaving the cab of the truck. A straddle carrier which will stack
cargo containers two high has been introduced by one industrial truck manufacturer ( 4 ) . The Van Carrier can drive straddle-fashion over a string of railroad flat-cars to remove a container from anywhere in the train. Containers can also be placed on or removed from flat-bed highway trucks. T h e carrier can lift containers from either the bottom or top. O n e manufacturer has announced a side-loading reach truck designed specifically for use in very narrow aisles (22). This truck is supported by “legs,” as in the case of a straddle truck, and consequently costly counterweight equipment is eliminated. T h e truck is operated perpendicular to the row of pallets, and upon positioning in front of a row of palletized materials, the forks reach out to the side, select the pallet, and retract it to the normal fork truck position. I n the area of attachments for fork trucks, there have been few new developments this past year. O n e new item, however, has caused considerable comment. A vacuum handling attachment was developed during the )ear for case goods, drums, and similar items ( 2 3 ) . While most of these units work in the vertical plane, the attachment can be adapted for use in the horizontal plane. A truck equipped with this device approaches a case, or stack of cases, suction cups are positioned by the operator, and when the vacuum is actuated the cases are handled by the truck in a fashion similar to normal fork truck handling. The obvious elimination of the fork truck entry under the package provides for cheaper packages and better utilization of cubic space.
Packaging T h e 13-gallon glass carboy, which is packed in a nailed wood crate, is expensive enough to require return, and considerable research has been done to develop a disposable replacement for bulk liquid shipment. T h e wire-bound Cubitainer (70, 7 5 ) has been jointly developed by a plastics firm and a wirebound research laboratory. This 15VOL. 52, NO. 2
FEBRUARY 1960
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Unit Operations Review
gallon package consists of three parts: a polyethylene insert, a corrugated liner which completely covers the insert on all six faces, and the wire-bound box. While approved only for use under a test permit number by the Bureau of Explosives a t the present time, it is fully expected that the container will receive full approval with continued use. Some of the advantages of this container are that no return is involved, return freight is eliminated, no cleaning of containers is required, bookkeeping is minimized, and large capital investment in containers is eliminated. I n addition, less tare and cube are required for the package, while two extra gallons are shipped per unit. Following development of the container in wood veneer face board material, Craveneer (paper overlaid veneer) was substituted successfully in the wirebound (76). This design appears to be superior considering over-all cost. Any liquid compatible with polyethylene can be shipped in these containers with proper test permits. T h e increased importance of materials handling has enlarged the packaging engineer’s responsibility. One multiwall bag manufacturer (77) has made competent engineering assistance in this field a fact with a materials handling engineer devoting full time to customer assistance and packaging engineer training. T h e shape of packages has a tremendous effect on the efficiency of materials handling ; packages designed for proper unit load sizing offer best utilization of available cubic space in both shipping vehicles and warehouses. A “square” fibre drum with capacities u p to 41 gallons has been developed. Known as the Ro-Con (Q), this container has round corners and convex sides and offers improved storage capacity above the standard cylindrical fiber drum; performance has shown that its design is sound. Another potential of the new shape in packages is the tetrahedron developed in Europe for the packaging of milk products and now being produced in America (5). At the fourth annual Flexible Packaging Competition held a t White Sulphur Springs, W. Va., converted polyethylene containers dominated awards presented for new packaging concepts (72). Continuous growth in the use of polyethylene as a packaging medium has been a stimulant to the plastics industry. T h e highly successful correspondence course in industrial packaging terminology presented by Purdue University is being followed by a correspondence course in materials of packaging. Registration for this course can be made by contacting the technical extension division of Purdue University (73).
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The importance of research in packaging has been expressed many times, yet we are all familiar with the conflict between research and application of data in practice. Finding a workable middle ground between directing research and development and allowing the researcher to experiment completely a t random is the topic of a discussion on developing an effective packaging research department (74).
Unit load Handling Three years of development have produced a unique design in a railroad freight car (27). This car will become available through normal railroad service in 1960 and was approved for general interchange service in 1959 by the mechanical division of the Association of American Railroads. Production models will have six separate compartments, each 85 inches long and 108 inches wide. Dividing the car into compartments has provided easier loading-from either side and without turning the lading to fit into a boxcar. Compartmentation was the solution to reducing the inertia of the lading to a point below that which causes damage. By restricting the total possible travel of the mass, inertia is minimized and damage virtually eliminated. T h e car is most useful in unit load shipping where lading fits the compartments and adequate facilities are available for continuous loading and unloading.
Bulk Handling Mentioned in the last review, the Dry-Flo hopper car (8) has emerged in the chemical industry. Designed to handle free-flowing solids in pellet or granular form, the cars are being used to ship polyethylene and polystyrene materials. T h e economics of using the car are such that savings result to both the shipper and receiver. Emergence of additional bulk hopper cars (78) by car builders indicates the trend to ship by bulk wherever feasible. Existing hopper cars equipped for gravity unloading have been modified for pneumatic-conveyor unloading. This modification consists of adding a flow tube or pneumatic outlet to the hopper sheet just above the discharge gate. When a pneumatic vacuum system is connected to the outlet valve, an air stream is created in the bridge conduit, and the lading is drawn through a 0.5-inch opening between the conduit and the sliding gate, through the outlet valve and the conveyor system into the storage bin. Use of private cars has been given a boost by the announcement of an increase in mileage allowance from the railroads to 4.5 cents per mile ( 7 7 ) .
INDUSTRIAL AND ENGINEERING CHEMISTRY
T h e increase in bulk shipments has resulted in increased emphasis in storage bins and conveying units. Depending upon the degree of product protection required and the amount of reaction between product and bin material, anything from concrete silos to galvanized bins ( 3 ) , to glass-lined or porcelanized bins (79) are being used. Both vacuum and positive pressure pneumatic conveying systems are designed for plastics handling (20, 24). The greatest area of need for bulk handling is containerization for intermediate bulk shipments. While several containers with a capacity of 40 to 70 cubic feet have made their debut, none have proved universally sound or economical. These containers have been divided between expendable and returnable types, and neither has the upper hand at present. Continued pressure from potential users should generate further development eventually leading to a satisfactory container.
literature Cited (1) Am. Management Assoc., 1515 Broadway, New York, N. Y., Conference on Distribution Management, October 1959. (2) Am. SOC.Mech. Engrs., 29 W. 39th St., New York 18, N. Y . , “Publications on Standards” (1959). ( 3 ) Butler Mfg. Co., Kansas City, Mo., “Bulk-0-Matic Tanks” (1959). (4) C1ark“Equipment Co., Battle Creek, Mich., Series 500 Van Carrier” (1959). (5) Distribution Age 58, 65 (May 1959). (6) Zbid., 58, 46 (November 1959). (7) Footlik, I. L., Secretary, CollegeIndustry Committee on Materials Handling Education, 9116 Four Winds Way, Skokie, Ill. (8) General American Transportation Corp., Chicago, Ili., “Dry-Flo Hopper Car” (1959). (9) Grief Brothers Cooperage, Delaware, Ohio, Bull. on Ro-Con (1959). (10) Hedwin Corp., Baltimore, Md., release on polyethylene film use (1959). (11) Hinsch, H. R., agent, 22 W. Madison St., Chicago, Ili., “Mileage Tariff 7-Q,” Suppl. NO. 5 (1959). (12) Industrial Packaging 5, 20 (November 1959’1.
( l 3 j -idih., p. 45 (September 1959). (14) Package Engineering 4, 52 (July 1959). (1 5) Package Research Laboratory, Rockaway, N. J., Bull. No. 369 (1959). (16) Russo, J. R., Chicago Mill and Lumber Co., 51 E. 42nd St., New York, N. Y . ,private communication, 1959. (17) St. Regis Paper Co., New York, N. Y., release on engineering services (1959). (18) Shipper’s Car Line, 750 Third Ave., New York, N. Y., “Ship-0-Matic Hopper Cars” ( 1959). (19) Smith, A. O., Corp., Kankakee, Ill., “Permaglas Storage Tanks” (1959). (20) Sprout, Waldron & Co., Muncy, Pa., Spec. Sheet 205 (1959). (21) Unit Load Car Corp., 1501 E. 96th St., Chicago, Ill., “Unit Load System” (1959). (22) Yale & Towne Mfg. Co., Philadelphia, Pa., Bull. No. 5263 (1959). (23) Zbid., Bull. NO. GS-658 (1959). (24) Young Machinery Go., Muncy, Pa., Bull. P-259 (1959).
