UNIT-IV Shop Floor Control and Flexible Manufacturing Systems UNIV-IV

Shop Floor Control Shop floor control (or) Production Activity Control Manages the detailed flow of materials inside the production facility UNIV-IV

Functions of Shop floor Control Scheduling Follow up Dispatching UNIV-IV

Phases of Shop floor Control Order Release Order Scheduling Order Progress UNIV-IV

Order Release This phase provides the documentation needed to process a production order through the factory This collection of documents referred as the shop packet Shop pocket consists of Route sheet- used to list the sequence of operations and tools required Material requisitions- used to get necessary raw materials from inventory Job cards- used to report the labour for each operation on the route sheet Move tickets- used to move the parts between the work centres Part lists- required for assembly jobs UNIV-IV

Order Scheduling It executes the dispatching function in production planning and control UNIV-IV

Elements of Order Scheduling 1.Machine loading- Allocating orders to work centres 2.Job sequencing- Determining priority in which the jobs should be proceed Priority Sequencing rules: Shortest operating time Earliest due date Slack time remaining-(Time remaining before due date-Processing time remaining) First come, first served- orders are run in the order they arrive in dept. Last come first, first served- orders arrive, they placed on top of the stock UNIV-IV

Order progress Monitors the status of the various orders in the plant, work –in progress and other progress in the shop floor Types of orders progress reports: Work order status progress- indicate the current status of each shop Progress reports- indicates the performance of each shop Exception reports- indicate the deviations from production schedule UNIV-IV

Factory Data Collection System (FDC) FDC consists of various paper documents , terminals and automated devices throughout the plant for collecting data on shop floor operations and compile and process the collected data for reference. Types of data collected by FDC Number of Pieces completed at a certain work centre Labour time spend on each order List and no. of parts that are scrapped List the no. of parts required rework Time clocks used by employees to punch in and out of work UNIV-IV

Objectives of Factory Data Collection System (FDC) To supply status and performance data to shop floor control system To provide up to date information To enable the management to monitor and implementation of master schedule UNIV-IV

Types of Data Collection System Online data collection system Offline data collection system The data are entered directly into the plant computer system and are immediately available to the order progress module. It always kept the details in current status UNIV-IV

Types of Data Collection System Offline data collection system The data are collected temporarily in a storage device (or) stand alone computer system Its easy to install and monitor It cannot provide up to date information to the shop floor UNIV-IV

Data Input Techniques 1.Manual/Clerical input techniques Job traveler- long sheet that travels with the shop packet through the factory Employee time sheets- daily time sheet is prepared for each worker Operation tear strips- set of preprinted tear strips Prepunched cards- Prepunched computer cards to each workers Disadvantages: Its depends on accuracy Manual errors are highly possible Delay on submitting the progress data Delay on compiling data UNIV-IV

Data Input Techniques 2. Data collection terminals- Workers to input data relative to order progress using simple keyboards (or) conventional alphanumeric keyboards EX: Push button keyboards, Workstation etc UNIV-IV

Automatic Identification methods Automatic data collection is essential for streaming the flow of information in CIM environments Types of Automatic identification techniques: Bar codes Radio frequency systems Magnetic stripe Optical character recognition Machine vision UNIV-IV

Bar code Technology https://www.youtube.com/watch?v=CFubTQ5p4xk UNIV-IV

Bar cods Commonly used bar codes are, Code 39 Interleaved two of five (ITF) Universal Product Code Code 93 Code 128 Postnet Codabar Plessey UNIV-IV

Bar cods UNIV-IV

Radio Frequency systems https://www.youtube.com/watch?v=MAA9JpGraoU UNIV-IV

Automated data collection systems Data acquisition systems Data logging systems Multilevel scanning UNIV-IV

Data Acquisition Systems (DAS) DAS is a computer system used to automatically collect data from process (or) piece of equipment. These perform an analysis of data (or) transfer the data to another computer for further use UNIV-IV

Data Logging Systems (DAS) Data logger is a device that automatically collects and stores data for off line analysis UNIV-IV

Multilevel Scanning More than one level of scanning Low level scan High level scan UNIV-IV

Flexible Manufacturing System (FMS) FMS is highly automate GT machine cell. A FMS is an individual machine (or) group of machines served by an automated materials handling system that is computer controlled and has a tool handling capability (Or) Multiple Machines that are integrated by an automated material handling system, whose operation is managed by computerized control system https://www.youtube.com/watch?v=BBC2oswnrt0 UNIV-IV

Components/Elements of FMS 1.Workstations 2.Material handling and Storage systems 3.Computer control systems 4.Human Resources UNIV-IV

1.FMS Workstations Load/unload Stations Machining Stations Assembly workstations Inspection Stations Other processing stations UNIV-IV

Load/Unload stations Loading and unloading of parts-either manually or automatically Data entry in system Soft movement of parts UNIV-IV

Machining Stations Automatic tool changing and tool storage Use of CNC Use of palletized work parts Machines Turning modules Milling modules Head indexers UNIV-IV

Assembly Workstations Replace the manual labour for assembling the parts In this workstations, products made of batches –(Robots are used) UNIV-IV

Inspection Workstations Inspection carried out for the assembly products Tools used Coordinate Measuring Machines(CMM) Special inspection Probes, etc UNIV-IV

Other Processing Workstations Sheet metal processing workstations Forging process stations,etc UNIV-IV

2.Material handling and storage system Part Transportation Raw material and finished product transportation Storage of Work pieces Wastes Empty pallets Fixtures and tools 1.Functions of material handling system 2.Types of FMS layout 3.Types of handling equipment used in FMS UNIV-IV

Functions of material handling system Random, independent movement of work parts between stations Handle of variety of work part configurations Temporary storage Convenient access for loading and unloading work parts Compatible with computer control UNIV-IV

FMS Layout UNIV-IV

FMS Layout Ladder layout UNIV-IV

Types of material handling equipment's Conveyors Cranes Industrial trucks Rail guided vehicles Automated guided vehicles Industrial robots UNIV-IV

Conveyors https://www.youtube.com/watch?v=HvFqo_ZOrsU UNIV-IV

Cranes https://www.youtube.com/watch?v=GwTsLysTtpQ UNIV-IV

Industrial trucks https://www.youtube.com/watch?v=bmU2CtcGIyQ UNIV-IV

Rail guided vehicle https://www.youtube.com/watch?v=UdC_Jm7hDs8 UNIV-IV

Automated guided vehicle systems(AGVS) https://www.youtube.com/watch?v=7xvP645fVnI https://www.youtube.com/watch?v=QKPIOny1AL4&index=4&list=PLQDv5 X70diTwDaucbQ7AyEuzwhQ8Bws0s UNIV-IV

Industrial robots https://www.youtube.com/watch?v=DYoBUhADU5s UNIV-IV