Facilities Planning
Using Digital Factory
Rezza Prayogi
Master Thesis
ACKNOWLEDGEMENT
I want to say thank you to everyone listed bellow, who gives a big impact in my life to continue finishing this master thesis.
To my God (Allah SWT), who always give me a power and a chance to do everything that’s impossible to do.
To my dad (Ali Djured) and my mom (Fariha), who always give me a support in everything I need to finish this master thesis.
To my uncle (Ir. Ismaun, MM), who always give me support to continue my study. To my beloved Rafika Amelia,SE, who always patient in waiting me finishing my
master degree.
To my Professor in Universität Duisburg-Essen (Prof.Dr.-Ing. Bernd Noche), who give me a chance and challenge to make this master thesis possible to finish.
To my all my friends in Universität Duisburg-Essen (Martinus Susilo, Dony Meitia, Kurnia Saputra, Monfi Subiharto, and a lot more), who always give me a bright day every day in Germany.
I also want to thanks to Prof. Dr.-Ing. P.Köhler and Prof. Dr.-Ing. Diethard Bergers that have been teaching us how to create a world class product using the best software and system that I have ever learn.
To Dassault Systemes, who create a great software (Solidworks and Delmia) that’s make me possible to create this master thesis.
There are more list that should be added here, I’m sorry to not be included here because of this paper space restriction. I want to thank you to all of you who have helped me, and to you who read my master thesis
Duisburg, 13 February 2008
Rezza Prayogi
Universität Duisburg-Essen (UDE) Institute for Product Engineering (IPE)
ABOUT THE COMPANY
In this Introduction, I give a brief description about Moryl Klebetecnik GmbH (as a source for my thesis data), SolidWorks, and Delmia QUEST.
1. Moryl Klebetechnik GmbH
H. Moryl GmbH has 15 years experience with the development and production of Gluing application and Measuring Technology for the most different traders.
Since beginning this year they are to be looked by the union of various specialists and by the construction of a competent distribution team in the position, the producing industry, directly and to supply. Therefore they save the detour about the retailers.
They are continuously anxious to adapt developments and constructions to the newest technological state to contribute thus to the best possible success for customer production. By the connection compatibility to all market friends to manufacturers they support its customer to reduce its spare part costs to a minimum.
They support of a producing, innovative and highly competitive partner with a being convincing complete program for a very good price achievement relation, from certified service about gluing application and measuring technology, they own control technology and ultrasonic technology up to servicing and repair of its customer systems.
They produces the following products: Piston pumps systems, gearwheel pumps systems, barrel glaze devices, coating states, automatic granulate material sponsor, order control, piston pumps, automatic tubes, pneumatics hand guns, surfaces order heads, order heads, spray order heads, order modules, nozzles for spray orders, tank filters and sieves, Inline filters, heating cartridges, Thermostat, magnet valves, glue fittings and screw connections, ultrasonic systems.
H.Moryl GmbH
Duderstädter Str. 13 D-40595 Düsseldorf Germany
2. Solidworks (a part of Dassault Systemes Corporation)
SolidWorks Office Premium is the complete 3D product design solution, providing your product design team with all the design engineering, data management, and communications tools that they need in one package. SolidWorks 3D mechanical design software, perform product design work more quickly and accurately. SolidWorks offers the most time-saving capabilities of any product design software available.
SolidWorks comes with Design Communication Tools. These tools demonstrate more effectively how products look and perform with SolidWorks Office Professional design presentation tools:
eDrawings Professional-- Generate accurate representations of 2D and 3D models that anyone can view, mark up, and measure without having to purchase their own mark up tools.
SolidWorks Animator-- Create compelling AVI files from SolidWorks parts and assemblies.
Photoworks - Create photorealistic images.
3D Instant Website-- Create and publish live web pages with 3D interactive content. SolidWorks comes also with CAD Productivity Tools. We can reduce design steps with SolidWorks Office Professional CAD productivity tools:
SolidWorks Toolbox-- Automate assembly tasks with a library of standard parts.
FeatureWorks-- Simplify the reuse of 3D CAD data created in varied file formats.
SolidWorks Utilities-- Find differences between two versions of the same part quickly and easily.
SolidWorks Task Scheduler--Saves time by enabling you to schedule resource intensive tasks, such as batch printing, running of analyses, and updating of project files during periods when you will be away from your workstation.
SolidWorks Design Checker - A timesaving tool for ensuring compliance with your organization's design standards.
SolidWorks Routing enables you to quickly and easily design pipe, tube, and electrical routes in your product designs.
SolidWorks ScanTo3D enables designers to open scan data in SolidWorks and convert it into surface and solid models.
SolidWorks comes with Design validation software, which called CosmosWorks. CosmosWorks specifically tailored for designers and engineers who are not specialists in design validation, CosmosWorks helps improve product quality by indicating how SolidWorks models will behave before they are built.
SOLIDWORKS CORP
300 Baker Avenue, Concorde, MA 01742
United States of America www.SolidWorks.com
3. Delmia (a part of Dassault Systemes Corp)
DELMIA QUEST provides a single collaborative environment for industrial engineers, manufacturing engineers, and management to develop and prove out best manufacturing flow practices throughout the production design process. Improve designs, reduce risk and cost, and maximize efficiency digitally, before spending money on the actual facility, to get it right the first time. By using QUEST to experiment with parameters such as facility layout, resource allocation, kaizen practices, and alternate scheduling scenarios, integrated product teams can quantify the impact of their decisions on production throughput and cost
DELMIA QUEST is a powerful simulation development and analysis tool for validating and visualizing the impact of process flow decisions made for meeting production requirements. Reduce risk by validating affordability measures, and minimizing problems and unplanned costs associated with facility startup. QUEST provides a complete solution, providing the tools necessary for both efficient process flow analysis and effective presentation of results to customers, managers, and other engineering disciplines.
DELMIA QUEST allows you to quickly build a simulation model to the level of detail required, adding more detail as necessary to improve accuracy throughout the design process. Conceptualize your processes by populating the model with intelligent objects and prebuilt sub-models from your libraries. Once your proposal is accepted, carry the same model into the design process by integrating it with existing design tools such as 2D/3D CAD, Microsoft spreadsheet and planning software, and other types of simulation applications such as ergonomic workplace assessment. Use the QUEST model to document the lessons learned through the systems integration process, quantifying the impact of design decisions.
As your facility springs to life in the digital world, the system’s behavior is emulated with real processing times, speeds, staffing levels, schedules, failure rates, and timing. This interactive digital environment allows accelerated “what if” analysis to be explored, for evaluating production scenarios, product mixes, and other alternatives. Results are efficiently communicated back to the product/process team for incorporating the best solutions. Finally, as the facility is built, use QUEST to author an Express model of your proprietary processes and integrate the simulation using QUEST Express™ with your MES, ERP, MRP, PLC, or scheduling systems for assisting in production floor analysis and systems monitoring. In each stage, analyzing and presenting QUEST results to decision makers is simple and effective.
DELMIA CORP
900 N. SQUIRREL RD., SUITE 100 AUBURN HILLS, MI 48326
PREFACE
This Master Thesis is based on the ISE Regulation and Master Study Plan for
Mechanical Engineering, that’s must be followed for each student in Universität
Duisburg-Essen.
This Master Thesis is created using my knowledge and combination lecture from Universität Duisburg-Essen, those lecture are:
Product Development (Produktentwicklung), Prof. Dr.-Ing. Diethard Bergers
Computer Aided Calculation and Simulation Methode (Computergestützte Berechnungs- und Simulationsmethoden), Prof. Dr.-Ing. P.Köhler
Simulation in Logistics I (Simulation in der Logistik I), Prof. Dr.-Ing. Bernd Noche Simulation in Logistics II (Simulation in der Logistik II), Prof. Dr.-Ing. Bernd Noche Logistics and Material Flow I (Logistik und Materialfluss I), Prof. Dr.-Ing. Bernd
Noche
Logistics and Material Flow II (Logistik und Materialfluss II), Prof. Dr.-Ing. Bernd Noche
Information System in Logistics (Informationssysteme in der Logistik), Prof. Dr.-Ing. Bernd Noche
Facilities Planning and System Engineering I (Anlageplanung und Systemtechnik I), Dr.rer.nat. Bachtaler
Facilities Planning and System Engineering II (Anlageplanung und Systemtechnik II), Dr.rer.nat Bachtaler
Industrial Engineering, Dr.rer.nat Bachtaler
This Master Thesis theme is to combine a theory and a practice in Facilities Planning using Digital Factory as a tool. In real world, people is still using manual method to conduct Facilities Planning, that’s why I want to prove it that using Digital Factory, people can learn, create, and take a result faster than using manual calculation. Digital Factory can make a Facilities Planner more understand about their Facilities, but it is only a tool, without a good knowledge it will become a dumb tool. So the person behind the Digital Factory is still a
Table of Contents
Acknowledgement ... I-2 About the company ... I-3 Preface ... I-6 Table of Contents ... I-7 Chapter I. Introduction ... 1-1 I.1. Facilities Planning ... 1-1 I.2. Digital Factory ... 1-3 Chapter II. Theory ... 2-1 II.1. Product Design ... 2-1 II.2. Process Design ... 2-2 II.3. Schedule Design ... 2-2 II.4. Facilities Design ... 2-3
II.5. Computer Simulation ... 2-3
II.6. How to Conduct Successful Facilities Planning ... 2-4
II.6.1. Design Product ... 2-4 II.6.2. Takt Time and Scrap Rates Calculation ... 2-6 II.6.2.1. Takt Time ... 2-6 II.6.2.2. Scrap and Rework ... 2-7 II.6.3. Process Design ... 2-8 II.6.3.1. Fabrication ... 2-8 II.6.3.1.1. Route Sheet ... 2-8 II.6.3.1.2. The Number of Machine Needed ... 2-9 II.6.3.2. Work Cell Load Chart ... 2-10 II.6.3.3. Assembly and Packout Process Analysis ... 2-11
II.6.3.3.1. The Assembly Chart ... 2-11 II.6.3.3.2. The Assembly Line Balancing ... 2-11 II.6.3.3.3. Packout ... 2-13 II.6.4. Equipment and Space Used ... 2-14 II.6.4.1. Workstation Design... 2-14 II.6.4.2. Space Determination ... 2-15 II.6.5. Material Handling Equipment Used ... 2-16 II.6.5.1. Material Handling Definition ... 2-16
II.6.5.2. Goals of Material Handling ... 2-16 II.6.5.3. The 20 Principles of Material Handling ... 2-17 II.6.5.4. The Material Handling Problem Solving Procedure ... 2-18 II.6.5.5. Material Handling Equipment ... 2-19 II.6.5.5.1. Types of Material Handling Equipment ... 2-19 II.6.5.5.2. Bulk Material Handling ... 2-20 II.6.5.5.3. Fork Lift Truck ... 2-20 II.6.6. Cost Calculation ... 2-25 II.6.6.1. How Much Will Our Product Cost? ... 2-25 II.6.6.2. Material Handling Cost ... 2-26 II.6.6.3. Cost Reduction Formula ... 2-26 II.6.7. Tips ... 2-27 II.7. How to Build Digital Factory ... 2-27
II.7.1. Getting Started With Delmia Quest ... 2-27 II.7.1.1. Introduction ... 2-27 II.7.1.2. Starting Quest ... 2-27 II.7.1.3. Configuration Files ... 2-30 II.7.1.4. The User Interface ... 2-31 II.7.1.5. Pull Down Menu (Context Button) ... 2-32 II.7.1.6. World Control Button ... 2-33 II.7.1.7. Using the Mouse ... 2-37 II.7.2. Step by Step to Build Delmia Simulation ... 2-37 Chapter III. Project and Calculation ... 3-1 III.1. Introduction ... 3-1 III.2. Design of Gas Grill ... 3-1 III.3. Takt Time and Scrap Rates Calculation ... 3-4 III.4. Process Design ... 3-7 III.4.1. Cycle Time and Fraction Equipment ... 3-7 III.4.2. Assembly Chart and Packaging Line ... 3-16 III.4.3. Flow Analysis Technique ... 3-22 III.4.4. Activity Relationship Analysis ... 3-40 III.5. Equipment and Space Used ... 3-50 III.6. Material Handling Equipment Used ... 3-57 III.7. Cost Calculation ... 3-61
Chapter IV. Building Digital Factory ... 4-1 IV.1. Delmia Quest ... 4-1 IV.2. Experiment ... 4-1 IV.2.1. Single Machine... 4-1 IV.2.2. Three Assembly Machine ... 4-2 IV.2.3. Conveyor System ... 4-4 IV.2.4. Power and Free System ... 4-5 IV.2.5. Labor, Shift, and Downtime ... 4-7 IV.2.6. Labor I ... 4-9 IV.2.7. Labor II ... 4-10 IV.2.8. Labor III ... 4-11 IV.2.9. Pallet ... 4-13 IV.3. Gas Grill Manufacturing Simulation ... 4-14 IV.3.1. Axle Production ... 4-14 IV.3.2. Tank Holder Production ... 4-15 IV.3.3. Bottom Support Production ... 4-20 IV.3.4. Top Support Production ... 4-24 IV.3.5. Control Panel Production ... 4-29 IV.3.6. Tube Plugs Production ... 4-33 IV.3.7. Legs Extensions Production ... 4-36 IV.3.8. Knob Production ... 4-39 IV.3.9. Legs Production ... 4-42 IV.3.10. Wood Slats Production ... 4-46 Chapter V. Conclusion ... 5-1 V.1. Advantages ... 5-1 V.2. Disadvantages ... 5-1 LYBRARY ... L-1 APPENDIX ... A-1 A.1. Appendix I – Delmia Quest Modeling Terms ... A-2 A.2. Appendix II – CAD Modeling Terms ... A-16
CHAPTER I
INTRODUCTION
I.1. Facilities Planning
Facilities planning determine how an activity’s tangible fixed assets best support achieving the activity’s objective. For a manufacturing firm, facilities planning involve the determination of how the manufacturing facility best supports production.
It is important to recognize that contemporary facilities planning considers the facility as a dynamic entity and that a key requirement to facilities plan is its adaptability, that is, that facility’s ability to become suitable for new use. In this regard as a facilities planner, the notion of continuous improvement must be an integral element of the facilities planning cycle. The continuous improvement facilities planning cycle shown in Figure I.1, details this concept.
Whether we are involved in planning a new facility or planning to update an existing facility, the subject matter should be of considerable interest and benefit. As depicted in Figure I.2, it is convenient to divide a facility into its location and its design components.
The location of the facility refers to its placement with respect to customer, suppliers, and other facilities with which it interfaces. Also, the location includes its placement and orientation on a specific plot of land.
The design components of a facility consist of the facility systems, the layout, and the handling system. The facility systems consist of the structural systems, the atmospheric systems, the enclosure systems, the lighting/electrical/communication systems, the life safety systems, and furnishings within the building envelope; and the handling system consists of the mechanisms needed to satisfy the required facility interactions.
The facility systems for a manufacturing facility may include the envelope (structure and enclosure elements), power, light, gas, heat, ventilation, air conditioning, water, and sewage needs. The layout consists of the production areas, production-related or support areas, and personnel areas within the building. The handling system consists of the materials, personnel, information, and equipment handling systems required to support production.
Determining how the location of a facility supports meeting the facility’s objective is referred to as facilities location. The determination of how the design components of a facility support achieving the facility’s objectives is referred to as
facilities design. Therefore, facilities planning may be subdivided into the subject of
facilities location and facilities design. Facilities location addresses the macro issues whereas facilities design looks at the micro elements.
Figure I.1 Continuous improvement facilities planning cycle1
Figure I.1 Facilities planning hierarchy1
1
Facilities Planning, 2nd ed. Tompkins, White, Bozer, Frazelle, Tanchoco, Trevino. McGraw-Hill
Specify/update primary and related activities to accomplish objectives
Determine space requirement for all activities
What’s the feasibility of incorporating the new operation or facility on existing site?
Develop alternative plans and evaluate
Select facilities plan
Implement plan Determine facility location Maintain and continuously improve Yes No Facilities location Facilities planning Facilities design
Facilities systems design
Layout design
I.2. Digital Factory
The digital factory defined (in Generic term) as a comprehensive network of digital models and methods among other things simulation and 3D-Visualization. Their purpose is the holistic planning, realization, controlling and current improving of all substantial factory processes and - resources in connection with the product
On the one hand by the digital factory an image of the material factory is understood, in order the processes running off therein to visualize, simulates and thus better to understand to be able. On the other hand the digital factory than the whole of all coworkers, software tools and processes, who are necessary for the production of virtual and material production, is defined.
Further must be separated between the tools and methods of the digital factory and the vision of virtual production and virtual logistics.
Virtual production designates as constant, experimentable planning, evaluation and control of production processes and - lay close with the help of digital models. The term of virtual logistics describes the software-supported planning of logistic processes and structures.
Effective range of the digital factory is the production planning phase within the product life cycle. During this phase the main operating cost blocks are specified.
Their purpose is the holistic planning, realization, controlling and current improving of all substantial factory processes and - resources in connection with the product (e.g. Motor vehicle, airplane).
With the digital factory the field of activity between the production development and the production control is closed. While for production development and production control different methods and systems on the free market are acquisition, production planning is only meagerly supported.
Principal activities during the product life cycle for the elucidation of the emphasis range of the digital factory can bee seen in Figure 1.1 below.
Figure I.1 Focus of the digital factory is production planning2
2
Reinhard, G.; Grundwald, S.; Rick, F.: Virtuelle Produktion – Virtuelle Produkte im Rechner produzieren. In: VDI-Z, 141, (1999) 12, S. 26.
The digital factory does not only consist of software. The digital factory must be seen in the total context of the enterprise and can into four levels of the digital factory be arranged in such a way:
Database
Integration platform Tools
Organization and planning workflow
A goal of the digital factory is it, proven methods, to standardize processes and operational funds in such a way that they can be used with another product or with the successor than planning components again. For this usually a revision of the existing processes and the organization is necessary.
During the process reorganization should on the four directions of attack of the digital factory.
common data base for the reduction of redundant data
Standardization of processes, resources as well as operational funds
consistent clarification of task, authority and responsibility over the process chain into a trade-spreading integrating process as well as
Possibilities for automation are respected. Tasks of the digital factory are among other things:
Assumption of the product planning data, Process time planning,
Planning of the production processes,
Planning of the operational funds (construction proposal, definition number), employment factor planning,
Layout planning of the work and the jobs, Cost evaluation as well as
Security of the results of planning
Delivery of the planning data to the enterprise.
Increase in value of the digital factory is not only that costs are lowered with the purchase by parts and plants, but offers also substantial advantages regarding maintenance, flexibility and reliability. Routine activities of planning are transferred to the software.
All process-taken part of planning settles its tasks at the computer and by Workflows are interlaced. Fixed times the progress in the planning process is made measurable. That secures the availability of the desired data at the correct time, in correct detailing and in the correct context.
All relevant planning data (product, process, resources) are only once seized by the ranges involved and administered by a data base. They are for each planner, in the future also for suppliers, outfitters and suppliers, always in the current form available. A nuclear goal is it to be able to use the data with new models very early to meet about in order for cost estimation.
Figure I.2 Area of digital factory3
However does not have itself the digital factory was located today (in the middle of 2007) surface covering in the producing industry as planning system interspersed. So far only large-scale enterprises trust in the new technology. Reasons for this are because of to high costs and the unclear use. Further it lacks in the operational daily business within many ranges the necessary user acceptance.
3
Reinhard, G.; Grundwald, S.; Rick, F.: Virtuelle Produktion – Virtuelle Produkte im Rechner produzieren. In: VDI-Z, 141, (1999) 12, S. 26
CHAPTER II
THEORY
II.1. Product Design
Product design involves both the determination of which products are to be produced and the detailed design of individual products. Decisions regarding the products to be produced are generally made by top management based on input from marketing, manufacturing, and finance concerning projected economic performance. In other instances, the lead times to plan and build facilities, in the face of a dynamic product environment, might create a situation in which it is not possible to accurately specify the products to be produced in a given facility.
If it is decided that the facility is to be designed to accommodate changes in occupants and mission, then a highly flexible design is required and very general space will be planned. On the other hand, if it is determined that the products to be produced can be stated with a high degree of confidence, then the facility can be designed to optimize the production of those particular products.
The design of the product is influenced by aesthetics, function, materials, and manufacturing considerations. Marketing, purchasing, industrial engineering, manufacturing engineering, product engineering, and quality control, among others, will influence the design of the product. In the final analysis, the product must meet the needs of the customer.
The drawing can be prepared and analyzed with computer aided design (CAD) systems. CAD is the creation and manipulation of design prototypes on a computer to assist the design process of the product. A CAD system consists of a collection of many application modules under a common database and graphics editor. The blending of computers and the human ability to make decisions enable us to use CAD systems in design, analysis, and manufacturing.
During the facilities design process, the computer’s graphics capability and computing power allow the planner to visualize and test ideas in a flexible manner. The CAD system also can be used for area measurement, building and interior design, layout of furniture and equipment, relationship diagramming, generation of block and detailed layouts, and interference checks for process oriented plants.
II.2. Process Design
The process designer or process planner is responsible for determining how the product is to be produced. As a part of that determination, the process planner addresses who should do the processing; namely, should be a particular product, subassembly, or part be produced in-house or subcontracted to an outside supplier or contractor? The ―make or buy‖ decision is part of the process planning function.
In addition to determining whether a part will be purchased or produced, the process designer must determine how the part will be produced, which equipment will be used, and how long it will take to perform the operation. The final process design is quite dependent on input from both the product and schedule designs. This will explained later in sub-chapter II.6.
II.3. Schedule Design
Schedule design decisions provide answers to questions involving how much to produce and when to produce. Production quantity decisions are referred to as lo size decisions; determining when to produce is referred to as production scheduling. In addition to how much and when, it is important to know how long production will continue; such a determination is obtained from market forecasts.
Schedule design decisions impact machine selection, number of machines, number of shifts, number of employees, space requirements, storage equipment, material handling equipment, personnel requirements, storage policies, unit load design, building size, and so on. Consequently, schedule planners need to interface continuously with marketing and sales personnel and with the largest customers to provide the best information possible to facilities design planners.
To plan a facility, information is needed concerning production volumes, trends, and the predictability of future demands for the products to be produced. The
general purpose will be the facility plan. The more specific the inputs from product, process, and schedule design, the greater the likelihood of optimizing the facility and meeting the needs of manufacturing.
II.4. Facilities Design
Once the product, process, and schedule design decisions have been made, the facilities planner needs to organize the information and generate and evaluate layout, handling, storage, and unit load design alternatives. Some tools frequently used by quality practitioners (e.g., Pareto chart) can be very useful in facilities planning efforts.
Figure II.2 Relationship between product, process, and schedule design and facilities Planning
II.5. Computer Simulation
Simulation is defined as an experimental technique, usually performed on a computer, to analyze the behavior of any real-world system. Simulation involves the modeling processor or a system where the model produces the response of the actual system to events that occur in the system over a given period of time.
Simulation can be used to predict the behavior of a complex manufacturing or service system by actually tracking the movements and the interaction of the system components. The simulation software generates reports and detailed statistics describing the behavior of the system under study. Based on these reports, the physical layouts, equipment selection, operating procedures, resource allocation and utilization, inventory policies, and other important system characteristics can be evaluated.
Simulation modeling has two important characteristics that set simulation apart from other forms of analysis. Simulation modeling is dynamic, in that behavior of the model is tracked over simulated time. A simple what-if analysis is static in nature. The state of a static model doesn’t change as a function of time. If we were simulate the roll of a die, then the output of the model would not affected by time. However, if we were to simulate the utilization or breakdown of a machine, or the accumulation of work-in-process inventory at a workstation, then these phenomena would not be static in nature. Equipment utilization or breakdown, material handling and transportation
Process design Facilities design Schedule design Product design
systems behavior, and interaction among various activities in a manufacturing cell, for instance, are dynamic in nature and the output of such models is a function of time.
Secondly, simulation is a stochastic model rather than a deterministic one. For example; if the mean time to failure (MTTF) for a piece of equipment is 1000 hours, it does not mean that the equipment will necessarily fail once every 1000 hours. Such an expectation would create a deterministic model. In the real world, the breakdown follows a particular statistical distribution, that is, exponential , Weibull, and so on. A random simulation model allows for these real-life breakdowns or other random occurrences.
Figure II.3 Computer simulations in manufacturing facilities design
Computer simulation and modeling are rapidly becoming important in the manufacturing and service segment of industry. Although computer simulation and modeling are not new to solving complicated mathematical problems or to providing insights into sophisticated statistical distribution, the power of the new generation software has dramatically increased the application of computer modeling as a problem-solving tool in the facilities design arena.
II.6. How to Conduct Successful Facilities Planning
To conduct successful facilities planning we need to make a lot of manual calculation and using excel. Data need to be collected before we make a trial and error calculation.
In this sub-chapter I will presented step by step how to do this, and a theory behind each step.
II.6.1. Design Product
Blueprints, bill of materials, assembly drawings, and model shop samples inform the facilities designer of the prime mission – a detailed description of what needs to be accomplished. The product design step is the source of this valuable
project is, ―What are we going to make?‖ The output of this product design step tells us exactly what we are going to manufacture.
Blueprints, sketches, pictures, CAD (Computer-Aided Design) drawings, and model shop samples all communicates the idea of what we want to build. There will be drawings of each individual part of the product as in Figure II.4. These drawings will tell us the size, shape, material, tolerances, and finish. Assembly drawings (see Figure II.1) show many parts (if not all parts) and how they fit together. An exploded drawing is an especially useful drawing for the facilities designer because it helps us to visualize how the parts fit together. Centerlines are used to separate parts and the parts are aligned to show the assembly relationship. These give the facility designer clues to the sequence of assembly.
Figure II.4 Sample blueprint for production purpose
When the facility designer is working on the assembly line layout, the exploded drawing will be the guide. The facility design cannot get started without blueprints or sketches.
Either a parts list or a bill of materials will be provided to the facility designer by the product engineering department with each new product. The part list and bill of materials are the same thing and list all the parts that make up a finished product. This list includes part numbers, part names, the quantity of each part, what parts make up subassemblies, and may include material specifications, parts and raw material unit costs, and make or buy decisions. The make or buy decisions are a total management decision not just the product engineering department, but the parts list is a good place to indicate that decision.
Table II.1 Indented Bill of Materials
Level Part No. Part Name Drwg. No. Qty/Unit Make/Buy
0 STG1 Packaged grill DWG1 1 M
1 PP1 Bottom grill casting PDWG1 1 B
1 PP2 Grease can wire PDWG2 1 B
1 PP3 Top grill casting PDWG3 1 B
1 PP4 Wood handle PDWG4 1 B
1 STG4 Legs DWG4 4 M
2 STG8 Top support DWG8 2 M
The intended bill of material is also an important aid in the design of the facility and configuration of the work cells and assembly lines (see Table II.1). An indented bill of material provides the same basic information as the parts list. However, the indented bill of material presents the hierarchical structure of the product by identifying each assembly, subassembly, and the required or subordinate parts of each assembly or subassembly. The highest level of the product, or the finished assembly, appears on the top of the list and is given level number zero (0). Under this are listed the major assemblies and each is assigned as level one (1). The period before
are listed and numbered level two (2). In turn, under each component, subordinate parts are listed and each is numbered as level three (3). If a given level itself is comprised of multiple parts, those parts would be listed following the given level three part and would be numbered level four (4), and ad infinitum. The purpose of the periods before each level number is to offset or indent (hence indented bill of material) each level in order to enhance readability.
The indented bill of material not only provides data regarding the composition of the final assembly, but it also provides valuable insight into the flow of parts and components in the final assembly.
Companies themselves do not fabricate every part of their product. The parts that are purchased complete are called buyouts and can be fabricated cheaper by someone else. Some companies purchase every part complete from outside. These companies are called assembly plants. The part that we ―make‖ are basic requirements for the fabrication end of our facility.
The product engineering department can be very helpful to the plant facility designer. It can point out special manufacturing problems, critical relationships, dimensions, and function. The product designer and the facility designer need to work closely together. The up-front communication and cooperation between the product designer and facility planner is one aspect of concurrent engineering.
II.6.2. Takt Time and Scrap Rates Calculation
II.6.2.1. Takt Time
Takt time can be defined as the maximum time allowed to produce a product in order to meet demand. It is derived from the German word taktzeit which translates to clock cycle. There is a logic therefore to setting the pace of production flow to this takt time. Product flow is expected to fall within a pace that is less than or equal to the takt time. In a lean manufacturing environment, the pace time is set equal to the takt time.
Takt Time is defined as:
𝑇 = 𝑇𝑎 𝑇𝑑 Where:
Ta = Net Available Time to Work eg. [minutes of work / day] Td = Total demand (Customer Demand) eg. [units produced / day] T = TAKT Time eg. [minutes of work / unit produced]
Net available time is the amount of time available for work to be done. This excludes break times and any expected stoppage time (for example scheduled maintenance, Team Briefings etc).
As an example, if you have a total of 8 hours in a shift (gross time) less 30 minutes lunch, 30 minutes for breaks (2 x 15 mins), 10 minutes for a Team Brief and 10 minutes for basic Operator Maintenance checks, then; Net Available Time to Work = (8 hours x 60 minutes) - 30 - 30 - 10 - 10 = 400 minutes.
If Customer Demand was, say, 400 units a day and you were running one shift, then your line would be required to spend a maximum of one minute to make a part in order to be able to keep up with Customer Demand.
In reality, people can never maintain 100% efficiency and there may also be stoppages for other reasons, so allowances will need to be made for these instances and thus you will set up your line to run at a proportionally faster rate to account for this.
Takt time has direct implications concerning the allowable time for completing individual steps in a production process. This is the case for both steps that modify (form, assemble, finish…) the product and also the steps that observe and control (test, measure, adjust…) the process. Similarly steps which require a part or assembly of the product to have been put into an accurately fixtured position must be completed in less than the total takt time so that time is allowed for loading and unloading or positioning the part in addition to the time for actually performing the production step. The quicker that a measurement or test step can be completed, the less constraint is placed upon product motion between steps. For example, a measurement process that captures the entire information about a part at once will permit shorter total takt time and a higher pace of production flow. Elimination of the need to measure reduces this step best (See SMED).
An implication of using takt time can be that work packages get reorganised. If worker one performs actions A1 through A5 and worker two performs actions A6 through A8 then a reduction in takt time may mean that there are now three work packages required to fit the new shorter/faster pace. They might be package 1 (A1 to A4), package 2 (A5 to A6) and package 3 (A7 to A8). So now we will have three people working to do the work that used to be achieved by two. This subdivision of workpackages rather than parallel working on unchanged packages of actions is a new idea to many. This way of working requires:
a very flexible workforce, that is willing to accept changes in their routines and workplace
requires a multi-skilled workforce, since now people may be asked to 'pick-up' actions currently performed by others
flexible workcells, since what is being done by two people today may need to accommodate three people tomorrow
increases hand-offs, so these must have no significant overhead
keeps the workflow simple and easy to manage, so whether the process will deliver is clear to all
has been observed to speed up individual steps in production, because the new context of each action encourages innovation.
It will be obvious that this kind of capacity replanning is not something that will be desirable every week. It is therefore important that the varying part of Takt time, the customer demand, should have been leveled before this kind of work replanning is undertaken. That leveling is looked at elsewhere and that therefore this style of capacity modification should be undertaken to meet long term customer demand changes and not weekly forecasts.
II.6.2.2. Scrap and Rework
Although quite undesirable, manufacturing operations do produces scrap or unusable parts. Furthermore, often here is a need to redo an operation simply because the part was not produce within the desired specifications the first time. This is called
rework. Scrap and rework result in an inefficient and wasteful use of the facilities
resources. Every effort should be made to eliminate such waste. However, as long as we have to deal with scrap and rework, we cannot ignore their demand on our production time.
Quality and production department have historical data that can indicate the level of rework and scrap for each operation. In determining the plant rate, or takt time, we must include scrap and rework rates into our calculations. Indeed, it is also prudent to add into these calculations the need for spare or replacement parts.
𝐼 = 𝑜𝑢𝑡𝑝𝑢𝑡
1 − %𝑠𝑐𝑟𝑎𝑝1 1 − %𝑠𝑐𝑟𝑎𝑝2 1 − %𝑠𝑐𝑟𝑎𝑝3 … (1 − %𝑠𝑐𝑟𝑎𝑝 𝑛)
To illustrate, if we need 2000 part/day with 3 operations, each operation has its own scrap rates. Operation 1 is 30%, operation 2 is 25%, operation 3 is 5%. We calculate how much we need this part is:
𝐼 = 2000
1 − 0,03 1 − 0,025 1 − 0,005 = 2,125 𝑢𝑛𝑖𝑡𝑠
II.6.3. Process Design
The process designer determines how the product and all its components will be made. The information provided by the process designer would include the following:
1. The sequence of operation to manufacturing every part in our product (they ―make‖ parts only because the ―buy‖ parts will not be our company’s problem) 2. The needed machinery, equipment, tools, fixtures, and so on
3. The sequence of operations in assembly and Packout 4. The time standard for each element of work
5. The determination of the conveyor speeds for cells, assembly and Packout lines, and paint or other finishing systems
6. The balance of the work loads of assembly and Packout lines 7. Load work cells
8. The development of a workstation drawing for each operation using all the principle of motion economy and ergonomics.
Process design can be divided into two broad categories, fabrication and
assembly. Fabrication process design is initially planned on a route sheet. Assembly
and Packout process design uses the techniques charts and assembly line balancing.
II.6.3.1. Fabrication
The sequence of steps required to produce (manufacture) a single part is referred to as the routing. We route the part from the first machine to the second machine and so on until we have a finished part that will be united with other parts. The form used to describe this routing is called the route sheet.
II.6.3.1.1. Route Sheet
A route sheet (see Table II.2) is required for each individual fabricated part of our product (make part). If our finished product that is to be manufactured has 30 different parts and we buy 10 from outside the company (buyouts), and make 20 parts ourselves, we will need 20 route sheets. The route sheet lists the operations required to make that part in proper sequence. The route sheet gets its name from the way it is used. A copy of the route sheet would be issued by the production and inventory control department showing the order quantity. The route sheet would accompany the material from operation to operation telling the operators what to do. The route sheet will tell the plant personnel about the part number, part name, quantity to produce, operation number, operation description, machine number, machine name, tooling needed, and time standard.
Table II.2. Route Sheet for one part
Part No. Part Name Drawing No. STG13 Knob DWG13 Operation No. Operation Description Machine Machine No. Cycle Time Fraction Equipment Pieces/ Hours Hours/ pieces Hours/ 1000 75 Molding NISSEI NS60 NS60 0,125 0,194 480 0,00208 2,083 65 Trimming Ergonomic Cutters ERGCT 0,060 0,093 1000 0,001 1
The route sheet ends with the last operation prior to being assembled with other parts. For example, if three parts are going to be welded together, the individual parts lose their identity once joined with other parts, so that the route sheet would end before welding. If an individual part goes through a clean, paint, and bake operation before being assembled, then the clean, paint, and bake procedure would be included on the route sheet.
The sequence of operations as shown on the route sheet affects the proper layout of the equipment on the production floor. We want the material to flow smoothly through the plant from the raw material stores to the first operation, to the second operation whose machine is right next to the first machine. This will ensure that the part travels as short a distance as possible. Process-oriented layouts are where you collect all like machines together and bring all parts to them, where product-oriented layouts place machine where they are needed to eliminate excessive moving. Skipping over machines and backtracking will result from process layouts and must be discouraged because it adds costs without adding to the value. When many parts are fabricated in one group of machines (called a process layout), jumping around may be necessary, but we want to minimize this jumping, skipping and backtracking. There are two ways to change the sequence in order to make the flow through the plant smoother:
1. Change the route sheet (paper change) if possible so that the sequence of operation agrees with the other parts or the plant layout.
2. Change the physical layout of the machines so that the machines are in the correct sequence.
Changing the paperwork is our first choice because it is the cheapest way.
Time standards are an important part of the route sheets. Time standards are used to determine how many machines are needed in our layout. They are another piece of information that may come from another group within the manufacturing engineering department, but in many companies, time standards are developed by the manufacturing facilities designer.
II.6.3.1.2. The Number of Machines Needed
How many machines should we buy? This question can only be answered when we know:
1. How many finished units are needed per day? 2. Which machine runs what parts?
How many finished units are needed per day? The marketing department tells us how many products to produce (manufacture) per day. Which machine runs what parts? The route sheets produced in the previous section will tell us which machines are needed to produce each part. What is the time standard for each operation for each part? The time standard for every operation on every part is in both pieces per hour and decimal minute. We need the decimal minute time standards to compare with the Takt Time.
Once we know the plant rate (takt time), the machines to be used, and the time standards, we divide the time standard (decimal minute) by the plant rate. The resultant number of machines should be in two decimal places (i.e., 0,46 machine). Once all the machine requirements for each operation have been calculated, we total similar machine requirements and round up recommending the purchase of enough machines. Always round up on the total machines, otherwise a bottleneck will be created and we will not produce exact number of product per day, unless our plant work overtime. If due to economic considerations, rounding up cannot be justified, overtime may need to be planned for these operations in order to meet production requirements and to alleviate bottlenecks. If investment can be justified, and the production volume is warranted, then rounding up is recommended.
This information on the number of machines required will be used later to determine the number of square feet of floor space needed in our fabrication department.
II.6.3.2. Work Cell Load Chart
The work cell load chart is different from the previous techniques in that it does not have to be for a complete part or product, but it could be for only a few operations. We could end up with a complete part; however, that it not the goal of a work cell.
A work cell is a collection of equipment required to make a single part or a family of parts with similar characteristics. This equipment is placed in a circle around an operator or operators (see Figure II.5). The operator (most often a single operator) then takes a part from the in-basket and moves that part around the circle of equipment. Equipment is usually automatic machines that only need to be loaded, activated, and then unloaded. Once the machine is loaded and activated, the operator moves the just completed part from the first machine to the second, where the operator removes the previous part and loads the next part. This process continues around the cell: taking parts out of one machine, putting new parts back into this machine, then activating that machine until arriving at the last machine, where the part is removed, inspected, and placed in the finished parts basket. Work cell are being developed at a very fast rate because they
1. Significantly reduce setup time
2. Eliminate all storage between operations
3. Eliminate most of the moving time between operations 4. Eliminate delays spent waiting for the next machine 5. Reduce cost
6. Reduce inventory (work-in-process reductions) 7. Reduce manufacturing in process time
Figure II.5. Work cell Layout
These are the goals of lean manufacturing and a good description of eliminating ―muda‖ or waste. The work cell concept considers operator (utilization) to be more important than machine utilization.
Work cell load charts are a special operations chart used for multi-machine situations. Work cell load charts will visually show the operator time, machine time, and walking time required to run a work cell to produce one part per cycle using many machines. The result of the work cell load chart will show us the total cycle time, proper utilization, and machine utilization. Because they are visual, work cell load charts help people to see problems and to make improvement on the operation by properly loading the operator, operators, and/or machines. A work cell will appear on the route sheet as one operation.
II.6.3.3. Assembly and Packout Process Analysis
Once all parts are produced by the fabrication departments or received from the suppliers and available for assembly, new analytical tools are needed. Subassembly, welding, painting final assembly, and Packout are all function included in this area of the plant.
II.6.3.3.1. The Assembly Chart
The Assembly Chart shows the sequence of operations in putting the product together. Using the exploded drawing and the part list, the layout designer will diagram the assembly process. The sequence of assembly may have several alternatives. Time standards are required to decide which sequence is best. This process is known as assembly line balancing.
II.6.3.3.2. Assembly Line Balancing
The purpose of the assembly line balancing technique is: 1. To equalize the work load among the assemblers 2. To identify the bottleneck operation
3. To establish the speed of the assembly line 4. To determine the number of workstations
In Out Drill# 1 4 holes Drill# 2 4 holes Ream 8 holes Tap 8 holes C‖ bore 8 holes 2 4 6 10 0 12 14 8
6. To establish the percentage workload of each operator 7. To assist in plant layout
8. To reduce production cost
The assembly line balancing technique builds on the assembly chart (Figure II.6) time standards and the plant rate (takt time). The objective of assembly line balancing is to give each operator as close to the same amount of work as possible. This can only be accomplished by breaking the taks into the basic motions required to do every single piece of work and reassembling the tasks into jobs of near equal time value. The workstation or stations with the largest time requirement is designated as the 100% station and limits the output of the assembly line. If industrial engineers want to improve the assembly line (reduce costs), they would concentrate on the 100% station. Reduce the 100% station in our example below by 1% and save the equivalent of 0,25 people, a multiplying factor of 25 to 1.
Figure II.6. Assembly Chart
II.6.3.3.3. Packout
Packout work is considered to be the same as assembly work as far as assembly line balancing is concerned. Many other jobs may be performed on or near the assembly line, but they are considered subassemblies and are not directly balanced
SA1 Grill Legs (2) Spot Weld (×2) Side Support (1) P1 Paint Paint SA2 P2 Control Panel (1) Paint Paint P.O SA3 P3 Bottom Support (2) Paint Paint SA4 Tank Holder (1) SA5 Wood Slats (4) SA6 Casting Ignitor Grates Gas Valving Burner SA7 Feet & Knob
Fasteners Instructions Poly Bag Purchase Parts Bagging Cardboard Box Staples Cardboard Packing
to the line because subassemblies can be stockpiled. Their time standards stand on their own merit.
II.6.4. Equipment and Space Used
II.6.4.1. Workstation Design
Choosing equipment comes from process design, but the space needed and workstation design must be calculated separately using ergonomics. The result of ergonomics and workstation design is a workstation layout, and the workstation layout determines the space requirements. The manufacturing department’s total space requirements are just a total of individual space requirements plus a little extra factor.
Ergonomics is the science of preventing muscular/skeletal injuries in the workplace. It is the study of workplace design and the integration of workers with their environment. Ergonomic considerations include employee size, strength, reach, vision, cardiovascular capacities, cognition, survivability, and cumulative muscular/skeletal injuries. The golden rule may be stated as follows: Design the work or the workstation
so that the task fits into the person rather than attempts to force the human body or psyche to fit into the job.
The resulting workstation design is a drawing, normally a top view, of the workstation, including the equipment, materials, and operator space. Designing workstations has been an activity performed by industrial and manufacturing engineers for nearly a century. During this period of time, the profession has developed a list of principles of ergonomics and motion economy that all new engineers should learn and apply. When these principles are applied to the design of a workstation, the most efficient and safe motion patterns will result.
―Where to start?‖ is the first question most often asked by new workstation designer. The answer is very simple – start anywhere! No matter where you start in designing a workstation, another idea will come along making that starting point obsolete. Where to start depends a great deal on what is to be accomplished at that workstation. The cheapest way to get into production is usually the best rule for the starting point. The cheapest way means just that – the simplest machines, equipment, and workstation. Savings must justify any improvement on this most economical method. Therefore, the designer is free to start anywhere, then improve on the first method.
The following information must be included in any workstation design: 1. Worktable, machines, and facilities
2. Incoming materials (materials, packaging and quantity must be considered) 3. Outgoing material (finished product)
4. Operator space and access to equipment 5. Location of waste and rejects
6. Fixture and tools
Figure II.7. Workstation layout for Bending Machine
A three-dimensional drawing would show an even greater amount of information. Any talented designer could attempt a three-dimensional design.
II.6.4.2. Space Determination
The space determination procedure for most production departments start with the workstation design. From each workstation layout, we measure the length and width to determine the square foot of each workstation.
Multiplying the total square feet by 150% allows extra space (this could be 200% if management wants to provide a spacious layout, or a larger contingency allowance) for the aisle, work in process, and a small amount of miscellaneous extra room. It does not include restrooms, lunchrooms, first aid, tool rooms, maintenance, offices, stores, warehouse, shipping, or receiving. The extra 50 to 100% space added to the equipment space requirement will be used mostly for aisles. Aisles can be very space consuming.
Table II.2 Example of Equipment Space Requirement
Machine Name Operation Machine code Space Required
JUTEC 850 Bender JTC850 106 ft2 = 9,85 m2
DrillPress Drill 8062 TRADESMAN 34 ft2 = 3,16 m2
Lincoln Resitance Welder LR560 67 ft2 = 6,23 m2
MINTER 300 Stamp MNS300 476 ft2 = 44,22 m2
Big 800 Wood/Steel Saw B800 152 ft2 = 14,12 m2
RYOBI Sander RBS 31 ft2 = 2,88 m2
SHARP Poly Bag J69 64 ft2 = 5,95 m2
Ingersoll Rand Paint Booth IR800 440 ft2 = 40,88 m2
NISSEI Injection Mold NS60 73 ft2 = 6,78 m 2
Small space consuming items such as an air compressor or drinking fountain may be included in this 50% extra area, but large area requirements must be designed
II.6.5. Material Handling Equipment Used
II.6.5.1. Material Handling Definition
Material Handling is the function of moving the right material to the right place, at the right time, in the right amount, in sequence, and in the right position or condition to minimize production costs.
Material control systems are an integral part of modern material handling systems. Part numbering systems, location systems, inventory control systems, standardization, lot size, order quantities, safety stocks, labeling, automatic identification techniques (bar coding) are only some of the systems required to keep industrial plants material moving.
Material handling can be broadly defined as all movement of materials in a manufacturing environment. The American Society for Mechanical Engineers (ASME) defines material handling as the art and science involving the moving, packaging, and storing of substances in any form. Material handling may be thought of as having five distinct dimensions: movement, quantity, time, space and control.
Movement involves the actual transportation or transfer of material from one point to the next. Efficiency of the move as well as the safety factor in this dimension is of prime concerns. The quantity per move dictates the type and nature of the material handling equipment and also cost per unit for the conveyance of the goods. The time dimension determines how quickly the material can move through the facility. The amount of the work in process, excessive inventories, repeated handling of the material, and order delivery lead times are affected by this aspect of the material handling systems. The space aspect of the material handling is concerned with the required space for the storage of the material handling equipment and their movement, as well as the queuing or the staging space for the material itself. The tracking of the material, positive identification, and inventory management are some aspects of the control dimension. Material handling is also an integral part of plant layout. They cannot be separated. A change in the material handling system will change the layout, and a layout change will change the material handling system.
Material can be moved by hand or by automatic methods, material can be moved one at a time or by the thousands, material can be located in a fixed location or at random, or material can be stored on the floor or high in the sky. The variations are limitless and only by cost comparison of the many alternatives will the correct answer emerge.
The proper material handling equipment choice is the answer to all our questions in this section. A material handling equipment list will include over 500 different types (classifications) of equipment, and if we multiply this number by the different models, sizes, and brand names, several thousand pieces of equipment are available for our use.
Material handling equipment has reduced the drudgery of work. It has reduced the cost of production and has improved the quality of work life for nearly every person in industry today.
But the handling of material is attributed to more one-half of all industrial accidents. Material handling equipment can eliminate manual lifting and also can cause injury, so do not forget about safety aspects.
II.6.5.2. Goals of Material Handling
The primary goal of material handling is to reduce unit costs of production. All other goals are subordinate to this goal. But the following sub-goals are a good checklist for cost reduction:
1. Maintaining or improve product quality, reduce damage, and provide for protection of materials.
2. Promote safety and improve working conditions. 3. Promote productivity:
a. Material should flow in a straight line.
b. Material should move as short a distance as possible. c. Use gravity! It is free power.
d. Move more material at one time. e. Mechanize material handling. f. Automate material handling.
g. Maintain or improve material handling/production ratios.
h. Increase throughput by using automatic material handling equipment. 4. Promote increased use of facilities:
a. Promote the use of the building cube. b. Purchase versatile equipment.
c. Standardize material handling equipment.
d. Maximize production equipment utilization using material handling feeders.
e. Maintain, and replace as needed, all equipment and develop a preventive maintenance program.
f. Integrate all material handling equipment into a system. 5. Reduce tare weight (dead weight)
6. Control inventory
II.6.5.3. The 20 Principles of Material Handling
The College Industrial Committee on Material Handling Education, sponsored by the Material Handling Institute, Inc. and the International Material Management Society has adapted the 20 principles of material handling.
The principles are guidelines for the application of sound judgment. Some principles are in conflict with others, so only the situation being designed will determine what is correct. The principles will be a good checklist for improvement opportunities.
1. Planning principle. Plan all material handling and storage activities to obtain maximum overall operating efficiency.
2. System principle. Integrate as many handling activities as is practical into a coordinated system of operations, covering vendor, receiving, storage, production, inspection, packaging, warehousing, shipping, transportation, and customer.
3. Material flow principle. Provide an operation sequence and equipment layout optimizing material flow.
4. Simplification principle. Simplify handling by reducing, eliminating, or combining unnecessary movement and/or equipment.
5. Gravity principle. Utilize gravity to move material wherever practical. 6. Space utilization principle. Make optimum utilization of building cube.
7. Unit size principle. Increase the quantity, size, or weight of unit loads or flow rate.
8. Mechanization principle. Mechanize handling operation.
9. Automation principle. Provide automation to include production, handling, and storage functions.
10. Equipment selection principle. In selecting handling equipment, consider all aspects of the material being handled – the movement and the method to be used.
11. Standardization principle. Standardize handling methods as well as types and sizes of handling equipment.
12. Adaptability principle. Use methods and equipment that can best perform a variety of tasks and applications where special purpose equipment is not justified.
13. Dead weight principle. Reduce ratio of dead weight of mobile handling equipment to load carried.
14. Utilization principle. Plan for optimum utilization of handling equipment and manpower.
15. Maintenance principle. Plan for preventive maintenance and scheduled repairs of all handling equipment.
16. Obsolescence principle. Replace obsolete handling methods and equipment when more efficient methods or equipment will improve operations.
17. Control principle. Use material handling activities to improve control of production inventory and order handling.
18. Capacity principle. Use handling equipment to help achieve desired production capacity.
19. Performance principle. Determine effectiveness of handling performance in terms of expense per unit handled.
20. Safety principle. Provide suitable methods and equipment for safe handling.
II.6.5.4. The Material Handling Problem Solving Procedure
Step 1. Analyze the requirement to define the problem. Be sure the move is required.
Step 2. Determine the magnitude of the problem. Cost analysis is best.
Step 3. Collect as much information as possible-why, who, what, where, when, and how
Step 4. Search for vendors. Suppliers often provide outstanding engineering and cost justification assistance.
Step 5. Develop variable alternatives
Step 6. Collect costs and savings data on all alternatives.
Step 7. Select the best method.
Step 8. Select a supplier.
Step 9. Prepare the cost justification.
Step 10. Prepare a formal report.
Step 11. Make a presentation to management.
Step 12. Obtain approvals (adjust as needed).
Step 13. Place an order.
Step 14. Receive and install equipment.
Step 15. Train employees.
Step 16. Debug (make it work) and revise as necessary.
Step 17. Place into production.
Step 18. Follow up to see what it is working as planned.
II.6.5.5. Material Handling Equipment
II.6.5.5.1. Type of Material Handling Equipment
There are literally thousands of pieces of material handling devices. These equipments vary from the most basic manual tools to the most sophisticated computer-controlled material handling systems that can incorporate a vast array of other manufacturing and control functions. Almost as varied and numerous are the classification strategy and methods of material handling equipment.
Traditionally, material handling equipment may be grouped into four general categories. The first category is the fixed-path or point-to-point equipment. This class of equipment serves the material handling need along a predetermined, or a fixed path. The most common and familiar example of a fixed-path system is the train and the railroad track. The train can travel from any point to any point and serve any point along the track system. Conveyor systems, powered, gravity-fed, or otherwise operated, fall into this classification. Fixed-path material handling systems are also referred to as continuous flow systems. Automated guided vehicles (AGV) fall into this group.
The fixed-area material handling system can serve any point within a three-dimensional area of cube. A jib crane or a bridge crane would serve as an example to describe this category of material handling systems. A jib crane installed on a floor pedestal can move parts and other material from any point in the x, y, and z direction; however, this ability is limited within confines of the equipment. Automated storage and retrieval systems (ASRS) also fall into this category.
The material handling equipment that can move to any area of the facility is referred to as variable-path variable-area equipment. All manual cars, motorized vehicles, and fork trucks can be pushed, dragged, or driven throughout the plant. What, then, would a jib crane that is installed on a mobile pedestal be called? Obviously, this is a compound material handling system. The crane is a fixed-area system and the pedestal is a variable-path vehicle. When the base is stationary the crane is confined within its reach.
The forth category consists of all auxiliary tools and equipment such as pallets, skids, automatic data collection systems, and containers.
How do we choose the proper piece of equipment from the thousands of material handling devices available to us? For the experienced project engineer or manager, this problem is not as great as it is for the novice. To assist the new facilities planner, the following organization of material handling equipment is suggested. This organization follows the flow of material from the receipt of material to the warehousing of that material as follows:
1. Receiving and shipping (they are similar) 2. Stores
3. Fabrication 4. Assembly 5. Packaging 6. Warehousing
This organization lends itself to specific problem-solving situations. Two additional areas of material handling are:
7. Bulk material handling
