Materials Technology Management.-GROUP-3.pptx

About Materials technology Management

1. TOPIC: Production Activity Control Presented by: Group 3

2. SUBTOPICS: • Production Activity Control (Planning, Implementation, and Control) • Data Requirements and Order Preparation • Scheduling, Load Leveling and Scheduling Bottlenecks • Theory of Constraints and Drum-Buffer-Rope • Production Reporting

3. PRODUCTION ACTIVITY CONTROL ➢ Production activity control (PAC) is responsible for executing the master production schedule and the material requirements plan. At the same time, it must make good use of labor and machines, minimize work-in-process inventory, and maintain customer service.

4. The material requirements plan authorizes PAC: • To release work orders to the shop for manufacturing • To take control of work orders and make sure they are completed on time. • To be responsible for the immediate detailed planning of the flow of orders through manufacturing, carrying out the plan, and controlling the work as it progresses to completion. • To manage day-to-day activity and provide the necessary support

5. The activities of the PAC system can be classified into planning, implementation, and control functions. 1. Planning ➢ The flow of work through each of the work centers must be planned to meet delivery dates, which means production activity control must do the following: • Ensure that the required materials, tooling, personnel, and information are available to manufacture the components when needed. • Schedule start and completion dates for each shop order at each work center so the scheduled completion date of the order can be met. This will involve the planner in developing a load profile for the work centers

6. 2. Implementation ➢ Orders that have tooling, material, and capacity have a good chance of being completed on time and can be released to the shop floor. Implementation is arrived at by issuing a shop order to manufacturing authorizing them to proceed with making the item. A shop packet is usually compiled and contains the shop order and whatever other information is needed by manufacturing. It may include any of the following: • Shop order showing the shop order number, part number, name, description, and quantity. • Bills of material • Route sheets showing the operations to be performed, equipment and accessories needed, materials to use, and setup and run times.

7. • Material issue tickets that authorize manufacturing to get the required material from stores. • Tool requisitions authorizing manufacturing to withdraw necessary tooling from the tool crib. • Job tickets for each operation to be performed. • Move tickets that authorize and direct the movement of work between operations.

8. 3.Control ➢ Once plans are made and shop orders released, the process must be monitored to learn what is actually happening. The results are compared to the plan to decide whether corrective action is necessary. Production activity control will do the following: • Rank the shop orders in desired priority sequence by work center and establish a dispatch list based on this information. •Track the actual performance of work orders and compare it to planned schedules. Where necessary, PAC must take corrective action by replanning, rescheduling, or adjusting capacity to meet final delivery requirements. • Monitor and control work-in-process, lead times, and work center queues. • Report work center efficiency, operation times, order quantities, and scrap.

9. Manufacturing Systems ➢ Manufacturing processes can be conveniently organized into three categories: 1. Flow manufacturing 2. Intermittent manufacturing 3. Project manufacturing

10. Flow Manufacturing ➢ Flow manufacturing is concerned with the production of high-volume standard products. There are four major characteristics to flow manufacturing: 1. Routings are fixed, and work centers are arranged according to the routing. 2. Work centers are dedicated to producing a limited range of similar products. 3. Material flows from one workstation to another using some form of mechanical transfer. 4. Capacity is fixed by the line. Two types of Flow Manufacturing 1. Repetitive manufacturing - if the units are discrete (e.g., cars and appliances) 2. Continuous manufacturing - if the goods are made in a continuous flow (e.g., gasoline)

11. Intermittent Manufacturing ➢ Production activity control in intermittent manufacturing is complex. because of the number of products made, the variety of routings, and scheduling problems, PAC is a major activity in this type of manufacturing. Characterized by many variations in product design, process requirements, and order quantities. This kind of manufacturing is characterized by the following: 1. Flow of work through the shop is varied and depends on the design of a particular product. 2. Machinery and workers must be flexible enough to do the variety of work. 3. Throughput times are generally long. 4. The capacity required depends on the particular mix of products being built and is difficult to predict.

12. Project Manufacturing ➢ Usually involves the creation of one or a small number of units. Large shipbuilding is an example. Because the design of a product is often carried out or modified as the project develops, there is close coordination between manufacturing, marketing, purchasing, and engineering.

13. DATA REQUIREMENTS ➢ To plan the processing of materials through manufacturing, PAC must have the following information: • What and how much to produce. • When parts are needed so the completion date can be met. • What operations are required to make the product and how long the operations will take. • What the available capacities of the various work centers are. Production activity control must have a data or information system from which to work. Usually the data needed to answer these questions are organized into data bases. The files contained in the databases are of two types: planning and control.

14. Planning Files 1 . Item Master File - There is one record in the item master file for each part number. The file contains, in one place, all of the pertinent data related to the part. For PAC, this includes the following: • Part number, a unique number assigned to a component. • Part description. • Manufacturing lead time, the normal time needed to make this part. • Quantity available. • Allocated quantity, quantities assigned to specific work orders but not yet with drawn from inventory

15. 2. Product Structure File (bill of material file) - contains a list of the single-level components and quantities needed to assemble a parent. It forms a basis for a “pick list” to be used by storeroom personnel to collect the parts required to make the assembly. 3. Routing File - contains a record for each part manufactured. The routing consists of a series of operations required to make the item. For each product, this file contains a step-by-step set of instructions describing how the product is made.

16. 4. Work Center Master File - collects all of the relevant data on a work center. For each work center, it gives details on the following: • Work center number • Capacity. • Number of shifts worked per week and number of machine hours per shift. • Efficiency and Utilization

17. Control Files ➢ Control in intermittent manufacturing is exercised through shop orders and control files that contain data on these orders. There are generally two kinds of files: the shop order master file and the shop order detail file.

18. Shop Order Master File ➢ Each active manufacturing order has a record in the shop order master file. The purpose is to provide summarized data on each shop order, such as the following information: • Shop order number, a unique number identifying the shop order and Order quantity. • Quantity completed. • Quantity scrapped • Quantity of material issued to the order. • Due date, the date the order is expected to be finished. • Priority, a value used to rank the order in relation to others. • Balance due, the quantity not yet completed. • Cost information.

19. Shop Order Detail File ➢ Each shop order has a shop order detail file contains a record for each operation needed to make the item. Each record contains the following information: • Operation number. • Setup hours, planned and actual. • Run hours, planned and actual. • Quantity reported complete at that operation. • Quantity reported scrapped at that operation. • Due date or lead time remaining.

20. ORDER PREPARATION ➢ Order preparation ensures that an order can be released to the shop floor only if the necessary tooling, materials, and capacity are available. Tooling isn’t usually included in material requirements planning (MRP), so it must be checked separately. If MRP software is used, it automatically checks and allocates materials; otherwise, production must check manually. Capacity availability must also be confirmed. Even with capacity planning systems, differences may exist between planned and actual capacity, so verification is essential. Checking capacity involves scheduling when it’s needed and ensuring work centers can handle the load.

21. SCHEDULING AND LOAD LEVELING Scheduling ➢ The objective of scheduling is to meet delivery dates and to make the best use of manufacturing resources. It involves establishing start and finish dates for each operation required to complete an item. To develop a reliable schedule, the planner must have information on routing, required and available capacity, competing jobs, and manufacturing lead times (MLT) at each work center involved.

22. Manufacturing Lead Time ➢ Manufacturing lead time is the time normally required to produce an item in a typical lot quantity. Typically, MLT consists of five elements: 1. Queue time, amount of time the job is waiting at a work center before operation begins. 2. Setup time, time required to prepare the work center for operation. 3. Run time, time needed to run the order through the operation. 4. Wait time, amount of time the job is at the work center before being moved to the next work center. 5. Move time, transit time between work centers

23. Scheduling Techniques Forward Scheduling ➢ Assumes that material procurement and operation scheduling for a component start when the order is received, whatever the due date, and that operations are scheduled forward from this date. The result is completion before the due date, which usually results in a buildup of inventory. This method is used to decide the earliest delivery date for a product. Forward scheduling is used to calculate how long it will take to complete a task. The technique is used for purposes such as developing promise dates for customers or figuring out whether an order behind schedule can be caught up. Example: If today is Sept. 1 and production takes 10 days, start immediately and finish by Sept 11.

24. Backward Scheduling ➢ Where planning starts from the due date of the order and works backward to determine when each task must begin. Ensures that production is completed just in time for delivery, minimizing inventory holding costs. Activities are scheduled as late as possible without delaying the final due date. Useful when the priority is meeting deadlines rather than finishing early. Backward scheduling is used to determine when an order must be started. Backward scheduling is common in industry because it reduces inventory. Example: Order due on Sept 30. If production takes 10 days, start on Sept 20 to finish exactly on time. In short: *Backward Scheduling = due-date driven (finish on time, not early) *Forward Scheduling = start-now driven (finish as early as possible)

25. Load Leveling ➢ Load leveling means distributing work evenly across machines, workers, and time so no one is overloaded while others are idle. It avoids sudden rushes (too much work at once) and gaps (no work at all). Helps keep production steady and smooth. Ensures resources (people, machines, materials) are used efficiently.

26. Example in a factory: * If a company must produce 200 products in 10 days: * Without load leveling → they might produce 100 in the first 3 days (causing stress and overtime), then slow down after. * With load leveling → they plan to make 20 products each day so work is balanced, easier, and on time.

27. SCHEDULING BOTTLENECKS * In factories, it’s hard to perfectly balance the workload for all machines or workstations. Some get too much work (overloaded) while others have too little (underloaded) . * The overloaded machines are called bottlenecks . They slow down the whole process because their capacity is less than the demand. Throughput means the total amount of work or products passing through the factory. Bottlenecks control the overall throughput — if they are slow, the whole system slows down. * To avoid piling up unfinished work, production must be scheduled based on the speed of the bottleneck. The purpose of scheduling bottlenecks is to make sure production runs smoothly and efficiently even when some machines or workstations have limited capacity

28. Main purposes: 1. Avoid delays – since bottlenecks slow everything down, scheduling around them prevents missed deadlines. 2. Control throughput – the bottleneck decides how much total work can pass through the system, so production is planned at its pace. 3. Prevent buildup of unfinished work – if faster machines produce too much ahead of the bottleneck, work piles up and wastes space/resources. 4. Use resources effectively – makes sure workers and machines are not sitting idle waiting for bottlenecks. 5. Improve flow – keeps production balanced and steady, reducing stress and overtime.

29. Managing Bottlenecks ➢ Since bottlenecks are so important to the throughput of a system, scheduling and controlling them is extremely important. The following must be done: 1. Establish a time buffer before each bottleneck – A time buffer is a small queue of materials placed before a bottleneck to make sure it never runs out of work. It protects the bottleneck from delays in feeding workstations by holding just enough inventory to cover expected disruptions, preventing shutdowns. 2. Control the rate of material feeding the bottleneck - The gateway operation regulates the flow so the bottleneck always has just enough work. 3. Do everything to provide the needed bottleneck capacity - Anything that increases a bottleneck’s capacity also increases the capacity of the whole system. This can be done through better utilization, reducing setups, and improving methods to cut setup and run times.

30. 4. Adjust loads - The load on a bottleneck can be reduced by using alternate work centers or subcontracting. Though costlier, this improves overall system throughput, increases sales, and boosts profits. 5. Change the schedule - Do this as a final resort, but it is better to be honest about delivery promises

31. THEORY OF CONTRAINTS AND DRUM-BUFFER-ROPE ➢ Eliyahu M. Goldratt’s Theory of Constraints (TOC) explains that production is made up of linked steps or processes. Each step has its own capacity, but usually there is one step (the bottleneck) that limits how much the whole system can produce. By focusing on and managing this bottleneck, companies can improve the efficiency and output of their entire operation.

32. Manage the Constraint ➢ Several fundamental guidelines have been developed for understanding how to manage a constraining process or bottleneck. Some of the more noteworthy include focusing on balancing the flow through the shop, time lost at a bottleneck is time lost to the whole system but time lost at a nonconstraint is a mirage, and transfer batches do not have to be the same size as process batches.

33. Improve the Process ➢ Once a constraint has been identified, there is a five-step process that is recommended to help improve the performance of the operation. The five steps are summarized as follows: 1. Identify the constraint - This implies the need to examine the entire process to determine which process limits the throughput. 2. Exploit the constraint - Find methods to maximize the utilization of the constraint toward productive throughput. 3. Subordinate everything to the constraint - Effective utilization of the constraint is the most important issue 4. Elevate the constraint - This means to find ways to increase the available hours of the constraint, including more of it. 5. Once the constraint is a constraint no longer, find the new one and repeat the steps - As the effective utilization of the constraint increases, it may cease to be a constraint as another process becomes one.

34. ➢ Even the scheduling system developed for the Theory of Constraints has its own specific approach. It is often described as Drum-Buffer-Rope: Drum - The drum of the system refers to the “drumbeat” or pace of production. It represents the master schedule for the operation, which is focused around the pace of throughput as defined by the constraint. Buffer - Since it is so important that the constraint never be “starved” for needed inventory, a “time” buffer is often established in front of the constraint. It is called a time buffer because it represents the amount of time that the inventory in the buffer protects the constraint from disruptions. Rope - The analogy is that the rope “pulls” production to the constraint for necessary processing. Although this may imply a reactive replenishment system, such as a reorder point, it can be done by a well-coordinated release of material into the system at the right time.

35. PRODUCTION REPORTING ➢ Production reporting provides feedback of what is actually happening on the plant floor. It allows PAC to maintain valid records of on-hand and on-order balances, job status, shortages, scrap, material shortages, and so on. Production activity control needs this information to establish proper priorities and to answer questions regarding deliveries, shortages, and the status of orders. Manufacturing management needs this information to make decisions about plant operation. Payroll needs this information to calculate employees’ pay.

36. Data must be collected, sorted, and reported. The particular data collected depend upon the needs of the various departments. The methods of data collection vary. Sometimes the operator reports the start and completion of an operation, order, movement, and so on, using an online system directly reporting events as they occur via data terminals. In other cases, the operator, supervisor, or timekeeper reports this information on an operation reporting form included in the shop packet. Information about inventory withdrawals and receipts must be reported as well.

37. ➢ Once the data are collected, they must be sorted and appropriate reports produced. Types of information needed for the various reports include: • Order status. • Weekly input/output by department or work center. • Exception reports on such things as scrap, rework, and late shop orders. • Inventory status. • Performance summaries on order status, work center and department efficiencies, and so on.

38. END OF THE PRESENTATION