Due to the increasing demand for a high variety of products and shorter espouse times in today's manufacturing industry, there is a need for highly flexible and efficient material handling systems. In the design off material handling system, addition, various other factors must be considered in an integrated manner. The next section describes the ten principles of material handling as developed by the Material Handling Industry of America (MAIM).It presents a guideline for selecting equipment, designing a layout, standardizing, managing, and controlling the material movement as well as the handling system.
Another section describes the common types of material handling systems. This chapter also discusses types of equipment, how to select material handling equipment, an operating model for material handling, and warehousing issues. It ends with a case study that implements some of these issues. TEN PRINCIPLES OF MATERIAL HANDLING If material handling is designed properly, it provides an important support to the production process.Following is a list often principles as developed by the MAIM, which can be used as a guide for designing material handling systems.
2. 1 Planning A plan is a prescribed course of action that is defined in advance of implementation. In its simplest form, a material handing plan defines the material (what) and the moves (when and where); together, they define the method (how and who). Five key aspects must be considered in developing a plan: 1.
The plan should be developed in consultation between the planner(s) and all who will use and benefit from the equipment to be employed. . Success in planning large-scale material handling projects generally requires a team approach involving suppliers, consultants when appropriate, and end-user specialists from management, engineering, computer and information systems, finance, and operations. .
The material handling plan should reflect the strategic objectives of the organization, as well as the more immediate needs. 4. The plan should document existing methods and problems, physical and economic constraints, and future requirements and goals. 5.The plan should promote concurrent engineering of product, process design, process layout, and material handling methods, as opposed to independent and sequential design practices. Ten Principles of Material Handling 3 2.
2 Standardization Material handling methods, equipment, controls, and software should be denaturized within the limits of achieving overall performance objectives and without sacrificing needed flexibility, modularity, and throughput. Standardization There are three key aspects of achieving standardization: 1.The planner should select methods and equipment that can perform a variety of tasks under a variety of operating conditions and in anticipation of changing future requirements. 2. Standardization applies to sizes of containers and other load-forming components, as well as operating procedures and equipment.
3. Standardization, flexibility, and modularity must not be incompatible. . 3 work The measure of work is material handling flow (volume, weight, or count per unit of time) multiplied by the distance moved. Material handling work should be minimized without sacrificing productivity or the level of service required of the operation.Five key points are important in optimizing the work: 1 .
Simplifying processes by reducing, combining, shortening, or eliminating unnecessary moves will reduce work. 2. Consider each pickup and set-down-? that is, placing material in and out of storage-? as distinct moves and components of the distance moved. . Process methods, operation sequences, and process/equipment layouts should be prepared that support the work minimization objective. 4.
Where possible, gravity should be used to move materials or to assist in their movement while respecting consideration of safety and the potential for product damage (see Figure 1 . ). 5. The shortest distance between two points is a straight line.
2. 4 Ergonomics Ergonomics is the science that seeks to adapt work or working conditions to suit the abilities of the worker. Human capabilities and limitations must be recognized and expected in the design of material handling tasks and equipment to ensure safe and effective operations. There are two key points in the ergonomic principles: 1 .
Equipment should be selected that eliminates repetitive and strenuous manual labor and that effectively interacts with human operators and users.The ergonomic principle embraces both physical and mental tasks. 4 Figure 1. 1 Gravity Roller Conveyor (Source: Courtesy of Pent) 2. The material handling workplace and the equipment employed to assist in that work must be designed so they are safe for people.
2. 5 Unit Load A unit load is one that can be stored or moved as a single entity at one time, such as a pallet, container, or tote, regardless of the number of individual items that make up achieves the material flow and inventory objectives at each stage in the supply chain.When unit load is used in material flow, six key aspects deserve attention: 1. Less effort and work are required to collect and move many individual items as a single load than to move many items one at a time. 2.
Load size and composition may change as material and products move through stages of manufacturing and the resulting distribution channels. . Large unit loads are common both pre- and postindustrial in the form of raw materials and finished goods. 4. During manufacturing, smaller unit loads, including as few as one item, yield less in-process inventory and shorter item throughput times.
5.Smaller unit loads are consistent with manufacturing strategies that embrace operating objectives such as flexibility, continuous flow, and Just-in-time delivery. 5 6. Unit loads composed of a mix of different items are consistent with Just-in-time and/or customized supply strategies as long as item selectivity is not compromised. 2. Space Utilization Space in material handling is three-dimensional and therefore is counted as cubic space.
Effective and efficient use must be made of all available space. This is a three- step process: 1. Eliminate cluttered and unrecognized spaces and blocked aisles in work areas (see Figure 1. ).
2. In storage areas, balance the objective of maximizing storage density against accessibility and selectivity. If items are going to be in the warehouse for a long time, storage density is an important consideration. Avoid honeycombing loss (Figure 1. 3). If items enter and leave the warehouse frequently, heir accessibility and selectivity are important.
If the storage density is too high to access or select the stored product, high storage density may not be beneficial. 3. Consider the use of overhead space when transporting loads within a facility. Cube per order index (CIO) storage policy is often used in a warehouse.
CIO is a storage policy in which each item is allocated warehouse space based on the ratio of its storage space requirements (its cube) to the number of storage/retrieval transactions for that item. Items are listed in a undersigning order of their CIO ratios. The first tem in the list is allocated to the required number of storage spaces that are closest to the input/output (1/0) point; the second item is allocated to the required Figure 1. 2 Retrieving material in blocked aisles 6 Figure 1. 3 Honeycombing loss number of storage spaces that are next closest to the 1/0 point, and so on.Figure 1.
4 shows an interactive places in the "Ten principles of Materials Handling" CD that allows a learner to understand the fundamental concepts of the CIO policy. 2. 7 System A system is a collection of interacting or interdependent entities that form a unified hole. Material movement and storage activities should be fully integrated to form a coordinated operational system that spans receiving, inspection, storage, production, assembly, packaging, intuiting, order selection, shipping, transportation, and the handling of returns. Here are five key aspects of the system principle: 1.Systems integration should encompass the entire supply chain, including reverse logistics.
It should include suppliers, manufacturers, distributors, and customers. 2. Inventory levels should be minimized at all stages of production and distribution, while expecting considerations of process variability and customer service. 3. Information flow and physical material flow should be integrated and treated as concurrent activities. 4.
Methods should be provided for easily identifying materials and products, for determining their location and status within facilities and within the supply chain, and for controlling their movement.For instance, bar coding is the traditional method used for product identification. Radio frequency identification (RIFF) uses radio waves to automatically identify objects as 7 Figure 1. 4 Example of CIO policy hey move through the supply chain.
The big difference between the two automatic data capture technologies is that bar coding is a line-of-sight technology. In other words, a scanner has to "see" the bar code to read it, which means people usually have to orient the bar code toward a scanner for it to be read.RIFF tags can be read as long as they are within the range of a reader, even if there is no line of sight. Bar codes have other shortcomings, as well. If a label is ripped, soiled, or falls off, there is no way to scan the item. Also, standard bar codes identify only the manufacturer and name as on every other gallon of the same brand, making it impossible to identify which one might pass its expiration date first.
RIFF can identify items individually. 5. Customer requirements and expectations regarding quantity, quality, and on-time delivery should be met without exception. 8 2. Automation Automation is concerned with the application of electro-mechanical devices, electronics, and computer-based systems to operate and control production and service activities.
It suggests the linking of multiple mechanical operations to create a system that can be controlled by programmed instructions. Material handling operations should be mechanized and/or automated where feasible to improve operational efficiency, increase responsiveness, improve consistency and predictability, decrease operating costs and eliminate repetitive or potentially unsafe manual labor. There are four key points in automation: 1 .Preexisting processes and methods should be simplified and/or reengineering before any efforts at installing mechanized or automated systems. 2. Computerized material handling systems should be considered where appropriate for effective integration of material flow and information management.
3. All items expected to be handled automatically must have features that accommodate mechanized and automated handling. 4. All interface issues should be treated as critical to successful automation, including equipment to equipment, equipment to load, equipment to operator, and control communications. . 9 Environment Environmental consciousness stems from a desire not to waste natural resources and to predict and eliminate the possible negative effects of our daily actions on the environment.
Environmental impact and energy consumption should be considered s criteria when designing or selecting alternative equipment and material handling systems. Here are the three key points: 1 . Containers, pallets, and other products used to form and protect unit loads should be designed for risibility when possible and/or biodegradability as appropriate. .
Systems design should accommodate the handling of spent teenage, empty containers, and other byproducts of material handling. 3. Materials specified as hazardous have special needs with regard to spill protection, combustibility, and other risks. 2. 10 Life cycle Life-cycle costs include all cash flows that will occur between the time the first dollar is spent to plan or procure a new piece of equipment, or to put in place a new method, until that method and/or equipment is totally replaced.A thorough economic analysis should account for the entire life cycle of all material handling Types of Material Handling Equipment 1 .
Life-cycle costs include capital investment, installation, setup and equipment programming, training, system testing and acceptance, operating (labor, utilities, etc. ), maintenance and repair, reuse value, and ultimate disposal. 2. A plan for preventive ND predictive maintenance should be prepared for the equipment, and the estimated cost of maintenance and spare parts should be included in the economic analysis.
3.A long-range plan for replacement of the equipment when it becomes obsolete should be prepared. 4. Although measurable cost is a primary factor, it is certainly not the only factor in selecting among alternatives. Other factors of a strategic nature to the organization that form the basis for competition in the marketplace should be considered and quantified whenever possible. These ten principles are vital to material handling system design and operation.
Most are qualitative in nature and require the industrial engineer to employ these principles when designing, analyzing, and operating material handling systems.In this section, we list various equipments that actually transfer materials between the multiple stages of processing. There are a number of different types of material handling devices (Meds), most of which move materials via material handling paths on the shop floor. However, there are some Meds-?such as cranes, hoists, and overhead conveyors-? that utilize the space above the machines. The choice of a pacific MAD depends on a number of factors, including cost, weight, size, and volume of the loads; space availability; and types of workstations.
So, in some cases the MESH interacts with the other subsystems. If we isolate MESH from other subsystems, we might get an optimal solution relative to the Meds but one that is suboptimal for the entire system. There are seven basic types of Meds (Herbage 2008): conveyors, palliatives, trucks, robots, automated guided vehicles, hoists cranes and Jibs, and warehouse material handling devices. In this section, we will introduce the seven basic types of Meds. In the following section, we will discuss how to choose the "right" equipment and how to operate equipment in the "right" way.
. 1 Conveyors Conveyors are fixed-path Meds. In other words, conveyors should be considered only when the volume of parts or material to be transported is large and when the transported material is relatively uniform in size and shape. Depending on the application, there are many types of conveyors-? accumulation conveyor, belt conveyor, power and free conveyor, pneumatic or vacuum conveyor, 10 roller conveyor, screw conveyor, slat conveyor, tow line conveyor, trolley conveyor, and wheel conveyor.
Some are pictured in Figure 1. 5.Our list is not meant to be complete, and other variations are possible. For example, belt conveyors may be classified as thorough belt conveyors (used for transporting bulky material such as coal) and magnetic belt conveyors (used for moving ferrous material against gravitational force).
For the latest product information on conveyors and other types of material handling equipment, we strongly encourage the reader to refer to recent issues of Material Handling Engineering and Modern Figure 1. AAA Industries) Conveyors used in serration applications (Source: Courtesy of BandleaderFigure 1. B Accumulation conveyor (Source: Courtesy of Nikkei, Belgium) 3 Types of Material Handling Equipment 11 Figure 1. C Extendable dock conveyor (Source: Courtesy of DVD, Germany) Figure 1.
Ad Belt conveyor (Source: Courtesy of FIG Logistic) Materials Handling. These publications not only have articles illustrating use of the 3. 2 Palliatives Palliatives are high-speed automated equipment used to palliative containers coming off production or assembly lines. With operator-friendly touch-screen controls, they palliative at the rate of a hundred cases per minute (see Figure 1. ), palliative two lines f cases simultaneously, or simultaneously handle multiple products. Figure 1.
E Chute and tilt-tray conveyor (Source: Courtesy of Demotic Corp.. ) (f) Figure 1 . If Overhead conveyor used in automobile assembly plant (Source: Courtesy of Gould Communications) 3. 3 Trucks Trucks are particularly useful when the material moved varies frequently in size, shape, and weight, when the volume of the parts or material moved is low, and when the number of trips required for each part is relatively small.
There are several trucks in the market with different weight, cost, functionality, and other features.Hand truck, fork lift truck, pallet truck, platform truck, counterbalanced truck, tractor-trailer truck, and automated guided vehicles (Agaves) are some examples of trucks.
