Bài giảng Operations Management - Chapter 12 MRP and ERP

MRP and ERPChapter 12Copyright © 2015 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.You should be able to:LO 12.1 Describe the conditions under which MRP is most appropriateLO 12.2 Describe the inputs, outputs, and nature of MRP processingLO 12.3 Explain how requirements in a master production schedule are translated into material requirements for lower-level itemsLO 12.4 Discuss the benefits and requirements of MRPLO 12.5 Describe some of the difficulties users have encountered with MRPLO 12.6 Describe MRP II and its benefitsLO 12.7 Explain how an MRP system is useful in capacity requirements planningLO 12.8 Describe ERP, what it provides, and its hidden costsChapter 12: Learning ObjectivesDependent vs Independent DemandLO 12.1MRPMaterial requirements planning (MRP):A computer-based information system that translates master schedule requirements for end items into time-phased requirements for subassemblies, components, and raw materials.The MRP is designed to answer three questions:What is needed?How much is needed?When is it needed?LO 12.2Overview of MRPLO 12.2Primary OutputsPlanned ordersA schedule indicating the amount and timing of future ordersOrder releasesAuthorizing the execution of planned ordersChangesRevisions of the dates or quantities, or the cancellation of ordersMRP Outputs: PrimaryLO 12.2MRP: DevelopmentThe MRP is based on the product structure tree diagramRequirements are determined level by level, beginning with the end item and working down the treeThe timing and quantity of each “parent” becomes the basis for determining the timing and quantity of the “children” items directly below it.The “children” items then become the “parent” items for the next level, and so onLO 12.3Example MRPShutterFrames (2)Wood sections (4)LO 12.3Example MRPLO 12.3Enables managers to easilydetermine the quantities of each component for a given order sizeTo know when to release orders for each componentTo be alerted when items need attentionAdditional benefitsLow levels of in-process inventoriesThe ability to track material requirementsThe ability to evaluate capacity requirementsA means of allocating production timeThe ability to easily determine inventory usage via backflushingExploding an end item’s BOM to determine the quantities of the components that were used to make the itemMRP BenefitsLO 12.4Consequence of Inaccurate DataMissing partsOrdering incorrect numbers of itemsInability to stay on scheduleOther problems Assumptions of constant lead timesProducts being produced differently from the BOMFailure to alter a BOM when customizing a productInaccurate forecastsMRP DifficultiesLO 12.5MRP IIManufacturing resources planning (MRP II)Expanded approach to production resource planning, involving other areas of the firm in the planning process and enabling capacity requirements planningMost MRP II systems have the capability of performing simulation to answer a variety of “what if” questions so they can gain a better appreciation of available options and their consequencesLO 12.6Capacity requirements planning (CRP) The process of determining short-range capacity requirements.Inputs to capacity requirement planningPlanned-order releases for the MRPCurrent shop loadingRouting informationJob timeKey outputsLoad reports for each work centerCapacity Requirements PlanningLO 12.7Enterprise Resource PlanningEnterprise resource planning (ERP) ERP was the next step in an evolution that began with MRP and evolved into MRPIIERP, like MRP II, typically has an MRP coreERP provides a system to capture and make data available in real time to decision makers and other users throughout an organization.ERP systems are composed of a collection of integrated modulesLO 12.8