How does the textbook describe the elements of PAC, and how does MRP impact these specific areas?
The textbox explains that for a JIT facility the job shop is no longer. There are no production area with high work in progress inventory, and long lead times. They are able to streamline the processes to job cells where the process is completed quickly with low work in progress inventory. “The shop-floor and vendor scheduling activities begin when an order is released. A critical information service provided by MRP is apprising the SFC systems of all changes in material plans. This means revising due dates and quantities for scheduled receipts so correct priorities can be maintained. ”
Jacobs, Berry, Whybark and Vollmann. Manufacturing Planning and Control for Supply Chain Management, 6th Edition. McGraw-Hill Learning Solutions, 2011. <vbk:0077609115#outline(11.1.2)>.
Which element of PAC (as described by the textbook and lecture) would be impacted the most by the material requirements plan?
The way how Aggregate Production Plan (APP) activities will or could affect Production Activity Control (PAC) is by the planning horizon. Because the aggregate production planning is concerning with demand forecasts into production and capacity level over a planning horizon, this can involve frequent changes in the size of the labor force or retaining a stable workforce that can leads in to inventory build ups during low demand period or idle time increase. While on the other hand, Production Activity Control (PAC) focus on scheduling and shop floor control activities.
The element of PAC as (described by the textbook and lecture) would impact the most by aggregate production plan is shop floor system, the reason is the “back end” approach takes into consideration all of the details of the company and considers the impacts specific details of a products will have on the operation. This will give the company to develop an individual plan that can be implement strategically.
I agree that the element of PAC that would be most impacted by the aggregate production plan would be the shop floor system. Shop floor control feedback is important for material and capacity planning, along with following up with vendors. Feedback can be given by status information like verification or disposition and/or by warning signals which flag certain parts that are in question. Shop floor planning should include elements of lead time, operational setbacks and lead time management. If any specific operation is not being performed it can setback the plan making anything that made it to the back end refer back to the engine stage of PAC.
Jacobs, Berry, Whybark and Vollmann. Manufacturing Planning and Control for Supply Chain Management, 6th Edition. McGraw-Hill Learning Solutions, 2011.
how does CRP impact these two sections of PAC?
The capacity plan is especially critical to managing the detailed shop-floor flow of materials. Capacity’s importance for shop-floor control (SFC) is illustrated by considering two extremes. If insufficient capacity is provided, no SFC system will be able to decrease backlogs, improve delivery performance, or improve output. On the other hand, if more than enough capacity exists to meet peak loads, almost any SFC system will achieve material flow objectives. Input/output analysis in the CRP system provides a method for monitoring the actual consumption of capacity during the execution of detailed material planning. It is linked to the shop floor execution systems, and supported by the database for production activity control (PAC). Input/output analysis indicate the need to update capacity plans as actual shop performance deviates from plans, as well as the need to modify the planning factors used in the capacity planning systems.
The time comes when plans must be put into action. 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.
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.
which element of PAC (as described by the textbook and lecture) would be impacted the most by the business plan?
The choice of objectives for PAC and PAC design reflects the firm’s position vis-à-vis its competitors, customers, and vendors and is impacted by the business plan. It also reflects the company’s fundamental goals and the constraints under which it operates. Some firms have more complex products and/or process technologies than others. The result can be a difficult shop-floor management problem and a resultant difference in the appropriate PAC system. As a result PAC system design must be tailored to the particular firm’s needs and business plan based on the SWOT analysis of the firm.
The element of PAC that would be impacted the most by the capacity plan is the shop floor systems. The shop floor systems determine scheduling of production. Capacity planning determines the capacity needed to meet changing demand. Poor capacity planning will lead to production schedules being ineffective.
I agree that the capacity plan plays an important part in PAC and it’s connection to MRP systems. Having a detailed capacity plan is vital when managing shop floor materials. Knowing the capacity is knowing what resources are available in order to meet material plans. If the capacity is not correct then the system delays delivery and output as well as increase backlogs. Now if you have enough capacity then it allows for a consistent flow with effective utilization. The goal is to create an even flow instead of the up and down or as the book says peaks and valleys.
Jacobs, Berry, Whybark and Vollmann. Manufacturing Planning and Control for Supply Chain Management, 6th Edition. McGraw-Hill Learning Solutions, 2011.
how important is lead time management in a PAC system?
Lead time includes the time needed to ship the parts from the supplier. The shipping time is included because the manufacturing company needs to know when the parts will be available for material requirements planning.
Lead time is important so that inventory can be minimized and shortages will be less prevalent. If the system maintains positive lead times, production will run smoothly, orders will be fulfilled on time and shipping time will not be an issue. When there is little or no lead time, quality will lack because people will be rushed, items will have to be taken from inventory which may deplete it completely and shipping could become an issue on the far back end of the spectrum.
Lead time is the element needed in order to be able to plan when material is needed for the production demand. There is lead time for out sourced suppliers to procure material to be introduced into production. This is important to the PAC system in that these lead times has to be taken into consideration when planning the order releases, shop floor schedules, purchasing, and vendor scheduling. You can’t promise a customer that you’ll have their product available for them next week when it takes 2 weeks to get the components from your supplier to even make the product. So lead times are very important when it comes to PAC.
Lead time management in a PAC system is very important, the reason for that is part of a PAC system responsibility is execution on scheduling and to review planned orders which is material availability. With short lead time the PAC system have a better control on job orders and work centers. Longer lead time will leads to more jobs in the system , that leads to longer queue, idle time, and more work-in-process inventory.
which specific area of PAC (as described by the textbook and lecture) is impacted the most by lead time management?
Well, I would think the shop floor is most affected because if we do not receive materials in time our work schedule would be thrown off so we would not be able to start jobs on the shop floor when we planned our book discusses in chapter 8 an “operation setback chart” (Jacobs 279) where we can see how delayed lead times can impact PAC. So that would be the shop floor and the MPS that are greatly affected by lead times. Long lead times, as Archibald mentioned affect work in process inventories which affect our costs.
Jacobs, Berry, Whybark and Vollmann. Manufacturing Planning and Control for Supply Chain Management, 6th Edition. McGraw-Hill Learning Solutions, 2011. <vbk:0077609115#outline(11.2.1)>.
I would have to say that MRP (material resource planning) would be impacted the most by lead time. MRP plans according to supplier lead time, transportation time, internal distribution time, along with other entities such as process time and material acquisition time. MRP is the main system that takes lead times into consideration when planning for material demand.
The lead time is the duration between placing an order until receiving the order. The time it takes a company to unload a product from a truck, inspect it, and move it into storage is non-trivial. With tight manufacturing constraints or when a company is using Just-In-Time manufacturing it is important for supply chain to know how long their own internal processes take.
So how do you think this will specifically affect each element of PAC?
Lead times impacts every element of PAC because every process requires time to process. For instance, when material is delivered to the plant, there in internal distribution time in which the material will be available for the production line. There is material acquisition time that the supplier needs in order to purchase material to procure. There’s transit time given for the amount of time it takes a supplier to ship and deliver to the facility.
It can actually grow far more complicated than this. Lead time is highly variable in a real world setting. Just one situation in which it changes dramatically is when a quality problem arises and an order needs to be replaced. An unexpected demand that needs to be met very urgently takes materials and production capacity earmarked for other orders. This means that the customer service rep needs to be able to quickly provide a lead time for the replacement order (which better be accurate since you’re dealing with an already agitated customer). This can then affect the lead time of all other open orders. Both aspects of PAC, the supplier systems and shop-floor systems, need to be involved in the replacement.
how important is lead time to a PAC system?
There are four elements of lead time and they are run, setup, move, and queue. With good Pac design and practice move and queue can be greatly reduced. Lead time is important because the longer the lead time between order and starting the more orders in the shop. The more orders there equal longer queue time.
The importance of lead time management in PAC system can not be understated. The time to deliver products from either the manufacturer or even one are of the operation to another needs to be monitored and managed to ensure that end products comply with delivery times. Understanding lead time is one of the major processes that allow suppliers as well as manufactures the ability to accurately determine when their products can reach the market.
which element of PAC is impacted the most by lead time?
All these areas in OPC: (1) the business plan, (2) the aggregate production plan, (3) the master production schedule, (4) material resource planning (MRP)/capacity resource planning [CRP]), and (5) production activity control (PAC) play vital role in with OPC, where each of these area are important. Each level varies it purpose, time span ( planning horizon), level of detail,. and planning cycles(frequency). At each one of these levels, there questions must be answers. For instance, what are the priorities, what is the available capacity, and how difference between priorities and capacity be resolved. The business plan is when senior management set major goals and objectives for further planning by marketing, finance, engineering and etc. The aggregate production plan is the quantities of each product group that must be produce in each period, desired inventory levels, and the resource of equipment, labor and materials needed in each period. The master production schedule is to break down the production plan to show for each period, the quality of each end item to be made. Material resource planning is when the component and service are needed to make each end item. Production activity control represents the implementation and control phase that require the responsible for planning and controlling the flow of work through the factory.
How does the textbook describe the core elements of PAC? And which one is impacted the most by the other four areas of OPC? Why do you say so?
The core elements of PAC are that MPS and MRP along with shop data, product data, performance and procurement all directly affect PAC. This in turn affects order release, shop floor scheduling, vendor scheduling, feedback, and order closing. – Detailed scheduling and control of jobs at work centers -reduction in work in process inventories and lead times -feedback from PAC can provide warnings to make changes – effective PAC results in good customer service.
In my opinion PAC is related to each of the five areas of OPC which are the business plan, aggregate production plan, master production schedule, master production schedule, MRP/CRP and last but not least production activity control (PAC). PAC is like the coordinator of manufacturing scheduling and controlling resources related to production of orders and tracking. It takes a plan and implements it to retrieve and achieve results in steps. The roles of PAC are to manage shop floor productions, work flow, scheduling and control work flow. For example im a factory and we make train whistles I would use the information from my MRP system to decide which products I plan to make, how many, scheduling, materials needed (BOM) and even total of jobs or orders completed and placed.
Activities in capacity resource planning (CRP) can have a significant impact on PAC. The most obvious of which is how much of the product is immediately available for use over a period of time. Another significant impact CRP can have on PAC is how the product is able to flow through a system. If capacity is calculated too low for demand then a system will see constant shortages and downtime. If the capacity is calculated too high then the system will have used more space than necessary which could result in increases in travel throughout the system.
What do you think are the three major prerequisites to an effective PAC system?
If I am reading into the hints appropriately, the engine is what feeds PAC. You mentioned the PAC is the back end of the OPC or MPC, which is made up of the front end, engine and back end (the sections of MPC). The engine, according to Fig 8-1 in the text, is made up of three elements; “detailed materials planning, detailed capacity planning and materials and capacity plans.” (Jacobs, 2011)
Having looked at Fig 8-1 in the text, I would argue that to make up an effective PAC, you need an accurate master production schedule, detailed materials and capacity plans and effective follow up that may improve the plans that are now in place. I say this because the master schedule feeds the materials and capacity planning which feeds the PAC. Having effective follow up that will improve the plans in place will only help the PAC be more effective time after time.
Jacobs, R. (2011). Manufacturing Planning and Control for Supply Chain Management (6th ed). McGraw-Hill Learning Solutions.
Retrieved from http://devry.vitalsource.com/books/0077609115/outline/11
The prerequisites to an effective PAC system is the three sections of the engine of MPC.
Three major prerequistes to an effective PAC system are master production schedule MPS, material requirement planning (MRP, and capacity requirement planning (CRP). All these system play a effective role in the PAC system, because MPS shows when products will be availables to PAC system, the material requirement planning ensure the availability of materials, components, and products for planned production and for customer delivery, and capacity requirement planning shows the requirements that need to meet production requirements.
an operations planning control (OPC) system contains five main elements:
* The business plan
* The aggregate production plan
* The master production schedule
* Material Resource Planning (MRP) / Capacity Resource Planning (CRP)
* Production Activity Control (PAC)
We also know that a Manufacturing, Planning, and Control (MPC) systems contains a Front End, Engine, and Back End that encompasses key elements of OPC.
With that being said, let’s end this week with a discussion on JIT. How is a JIT strategy and its principles directed toward a PAC system?
JIT strategy and it principles directed toward a PAC system with reductions in raw material, WIP, finished inventory, reduce space needed for WIP and inventory, setup time reductions and improved cycle rate. It also improve machine and employee productivity. Utilizing JIT principle is a low risk and high reward proposition.
JIT does not focus on capacity like MRP does. With JIT the capacity does not have to be defined because the main principles of JIT are to get products in and get them out. With JIT, there is much waste reduced, costs are reduced, and there isn’t a need for scheduling. All this in turn allows for a smoother PAC if all works as it should.
JIT systems are designed to produce products on an order to order basis, produce them and ship them our the door. It is not inventory driven and is often times even used to reduce inventory. In most cases it is more economical when using the PAC system. JIT is most effective when the same types of products are being produced frequently rather than new and ever changing production. An MRP system would be more effective for that type of business.