PRODUCTION PLANNING AND CONTROL-PPC notes - Free download as PDF File .pdf), Text File .txt) or read online for free. Industrial & Management Engineering Department. Industrial Relations. IM Lecture 4: Production Planning and Control. Dr. El‐Sayed Saad. Dr. Yehia. Production Planning and Control, PPC Study Materials, Engineering Class handwritten notes, exam notes, previous year questions, PDF free download.
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Lectures Notes. cFor limited distrubution to IE students. All other rights reserved. IE PRODUCTION PLANNING AND CONTROL. Rakesh Nagi. INTRODUCTION: Definition – Objectives of production Planning andControl Important functions covered by production planning and control (PPC) function in. Production planning and control is a tool available to the management to achieve Thus production planning and control can be defined as the “direction and.
Pr oducti on Pl anni ng And Cont r ol 6 ii Lot or batch planning. As used here, it refers to the establishment of policies, procedures, and facilities for manufacturing operations to produce product required for future. It is ultimately tied to both capacity planning and product determination in which products will be produced and in what quantities and is future oriented. It looks ahead ensure that the inputs consists not only of machinery and raw materials but of people skills, control systems funds and various types of inventories. In essence, production planning make sure that everything is available on time to meet the production target manufacturing system is circumscribed by various limiting factors such market price quality delivery requirements, funds availability and inherent product restrictions like process time or special storage requirements.
Size of the plant. The type of industry i. Industries can be classified into types by several methods; by availability of different kinds of labour in different geographical locations, by the demand for different grades of skills, and by the factors relating to investment policy.
To determine capacity of all manufacturing departments and to plan systematically coordinated and related production activities within the scope of the enterprise to meet sales requirements.
To translate orders received from sales department into orders on the works department and to ensure steady plans of production activities. To find ways and means through which product manufacturing requirements such as materials and their necessary constituents such may be available in right quality and quantity at the right time.
To coordinate a number of different department groups so that a fine balance of activities may be maintained. To promote fuller utilization of plants. To assist labour towards right and greater earnings. To train staff in the effective performance of their duties.
The basic cycle of events in the control are Action, Feedback, Evaluation and Adjustment. Since these events are dynamically in continuous they take the form of a closed-loop circuit. There are seven essential steps in the establishment and application of operating controls. These steps will be discussed in their normal sequence and is diagrammatically represented in figure 1. A Operation : The first step in the control cycle is operation.
In this step, the act of doing something, some faults will be obvious and, therefore, easily corrected. Other faults will be more deceptively concealed requiring the steps that follow to reveal them so that they can be dealt with.
B Measurement : The second step is so measure what is being done. In the field of quality control for example, variations in physical, chemical, electrical, dimensional and other properties are measured.
In production control, all operations are measured to determine the time required for their performance and the capacities of equipment with which work is done.
In www. C Capabilty Studies : Analysis of measurements in step two, aided by many reliable statistical technique gives an accurate projection of what actually can be done. In production control we need to know quality process capabilities so that scrap and defer losses can be figured. Studies of process capabilities tell us what we can do. D Objectives : After we discover what we can do, we are ready to figure out what we should as this may either be more or less than our capabilities.
This decision then leads to plans for using excess capabilities on other plans to increase capabilities either for quality or quantity so that the objective can be met.
Production system may occur in factories, banks, stores, hospitals etc. In all instances, some input to the system is being processed within the system to produce a goods or services as an output; we are in fact dealing with the operations phases of any enterprise. Three main factors may be said to determine the place of production planning and control in an organization. The type of production i. Size of the plant.
The type of industry i. Industries can be classified into types by several methods; by availability of different kinds of labour in different geographical locations, by the demand for different grades of skills, and by the factors relating to investment policy.
To determine capacity of all manufacturing departments and to plan systematically coordinated and related production activities within the scope of the enterprise to meet sales requirements.
To translate orders received from sales department into orders on the works department and to ensure steady plans of production activities.
To find ways and means through which product manufacturing requirements such as materials and their necessary constituents such may be available in right quality and quantity at the right time.
To coordinate a number of different department groups so that a fine balance of activities may be maintained. To promote fuller utilization of plants. To assist labour towards right and greater earnings. To train staff in the effective performance of their duties. The basic cycle of events in the control are Action, Feedback, Evaluation and Adjustment.
Since these events are dynamically in continuous they take the form of a closed-loop circuit. There are seven essential steps in the establishment and application of operating controls. These steps will be discussed in their normal sequence and is diagrammatically represented in figure 1. A Operation : The first step in the control cycle is operation. In this step, the act of doing something, some faults will be obvious and, therefore, easily corrected.
Other faults will be more deceptively concealed requiring the steps that follow to reveal them so that they can be dealt with. B Measurement : The second step is so measure what is being done. In the field of quality control for example, variations in physical, chemical, electrical, dimensional and other properties are measured. In production control, all operations are measured to determine the time required for their performance and the capacities of equipment with which work is done.
In P r od u c ti o n P l a n n in g An d C on t r o l 9 automatic electronic and mechanical operations must be measured accurately in terms of milliseconds before a whole system can be integrated. C Capabilty Studies : Analysis of measurements in step two, aided by many reliable statistical technique gives an accurate projection of what actually can be done.
In production control we need to know quality process capabilities so that scrap and defer losses can be figured. Studies of process capabilities tell us what we can do. D Objectives : After we discover what we can do, we are ready to figure out what we should as this may either be more or less than our capabilities. This decision then leads to plans for using excess capabilities on other plans to increase capabilities either for quality or quantity so that the objective can be met.
E Evaluations : As the information is fed back from operations, it is compared with plans and objectives other evaluations are used to adjust budgets and costs. F Adustment : The last step in production control is adjustment. Production control adjustments are complicated because they often require increasing or reducing quantities based upon past operation and sales in quality control adjustments are made to maintain product quality requirement within limits.
The figure 1. In it, image two rotating sequence on the basic elements of action, feedback and evaluation that come logure in compound adjustment.
This is based on the current information. But if we do know where the first shot has hit, we can adjust the aim for next one and thus improve our marksmanship. V Estimating: Availability of plant equipment and its component parts.. It depends upon the drawing.
This section establishes the operation necessary to manufacture the proper sequence on route sheet and operation sheet.
Human elements. Manufacturing type employed. Characteristic of physical plant equipment and its component parts. Decision as whether to fabricate a component or download it from elsewhere. It depends primarily upon the manufacturing involved. This depicts the additional material needed Figure 1.
Analysis of cost article: It includes cost accounting department for cost estimating of product. Factors Affecting Routing Procedure: It estimates the operations. The schedule thus provides a short range sequence of activities one for which we must have sensitive controls and rapid response time. The schedule is very detailed plan for an immediate and relatively short time period.
The difference between the plan and the schedule can be illustrated by looking at the objectives. Perhaps the most simple type schedule can be illustrated by an example drawn from cottage industry.
But many other activities are also scheduled such as maintenance. The schedule will to produce units of articles during week number 1. Scheduling can be very simple or very complex.
Machine loading is carried out in connection with routing to ensure smooth work flow work estimating. At this levels of detail. This involves determination of the individuals machines that are going to produce the items when they will be started and completed what quantities lot or Batch sizes they will be produced and with what materials. Scheduling often refers to the specific determination of what is going to the production during the next few weeks or months.
The control is very simple and consists primarily of a count made each week. On the hand. The distinction between planning and scheduling is largely semantically and based upon difference in detail and time period.
The plan may ask to double production within two years. It may be consequently results in wide scatter of operation times and unduly large fluctuation and perhaps instabilities in time schedules. Machines have to be loaded according to their capabilities performance the given and according to the capacity.
Careful analysis of process capacities so that flow rates along the various production lines can be suitable coordinated. A worker may be asked to produce as given number of work carvings or square meters of handloom fabric per week. In fact. Schedule jobs on a random basis. Each of these rules usually in combination with others provides a means of regarding tasks. Companies often experiment of determine the specific set of rules which make sense for their particular situations.
The selection of the particular rules will largely depend upon the particular circumstance for which they are required. Schedule jobs in the order they are received.
Yet their function is vital to the achievement of such ends. Not only do they serve the purpose of linking the scheduling function with the attainment of total organizational goals but they provide consistency in scheduling practice so that people can be interchanged.
Competitive made of conditions. There are an almost unlimited number of possibilities including the converse of some of the above and these are provided solely for illustration.
The scheduling function is such a detailed process that it must usually be delegated to middle or lower management levels. They also make it possible to place much of the scheduling detail work on computers. Schedule the longest jobs first. Schedule all jobs first which requires operation in department 1.
Schedule the job with the earliest delivery dates first. Decision rules can take many forms. Decision rules for scheduling should be fairly specific. Schedule first those jobs with the use production facilities for which we have the greatest idle capacity.
It is worth noting that such decision rules are applicable to all scheduling processes not only these which deal with production operations. Schedule customer As order before all others. If the rules are well constructed they should tend to maximize benefits to the firm as a whole and should not be changed capriciously by individuals who cannot see the impact of such changes on overall corporate goals.
A point often overlooked is that if decision rules for scheduling are not formally and explicitly established. Movement of material from stores to the first process and from process. Meaning of this term is sending to destination or starting something on way. In dispatching translated into reality or physical work which has been planned scheduling. This can be very useful and save considerable relief and confusion as follows the testing of such rules without the disruption of production.
Sometimes this may be the best the alternative for a firm e. On the other hand. Assignment of work to different machines of work place men. VII Diaspatching: It is important mechanism of production control. Issue of tool orders. Duties of Dispatching: When applied to production control. Each person involved in the scheduling process will usually have his own method-perhaps one that makers sense only to him. It is extremely difficult to design any set of rules which will cover every situation.
Issue of time ticket. Dispatching Procedure: Manner in which schedule or orders are issued depends upon whether the dispatching decentralized or centralized in the Decentralized: The manufacturing schedules or work orders in blanket fashion to the foreman or dispatch clerk within department.
Minimum stock: Slack equals calendar time remaining minus processing time remaining or slack equals date minus present time minus set up and machining time all remaining operation. This closely inter elated with activities of dispatcher to whom is delegated scheduling responsibility. Regardless of type of dispatching it is customary for department to department themselves informed of the starting dates. Result at low variance of manufacturing cycle time.
Recording time of beginning and completing jobs hand calculate duration of. Recording and reporting idle time of machine and operation. First come first served: Run the job which arrived in the waiting line first.
Issue of more orders and collection of time tickets. It is duty of foreman or clerk to dispatch the orders of material to each machine and operator. Critical equals 0 to due date minus present time divided by number of days required to complete the job order. In centralized dispatching: This involves the dispatching of orders from central dispatching division to machine or work station. Combination Rule: Critical ratio: The critical ratio are made to order work is a slack type rule.
Earliest due date: Run the job with the earliest due date. Capacity and characteristic of each machine is recorded in central dispatching station.
VIII Expediting: Follow up which regulates the progress of materials and parts through the production process. Dispatching Rule: Simple Rule: Shortest processing time: Run the job which has the shortest set up plus machining for the current work centre. The essential task of dispatching and evaluating are concerned with the immediate issue of production and with measures that will be as certain fulfillment target. X Evaluating: Perhaps the most neglected. This can be accomplished most simply by filling one copy of requisition in a daily follow up file or in ticket file according to the date of materials is due to be received.
Thus here the evaluating function comes in to provide a feedback mechanism on the longer term basis so that the past experience can be evaluated with the view to improving utilization of method and facilities. It serves as a catalytic agent to fuse the various separate an unrelated production activities into the unified whole that means progress. Valuable information is gathered limited in nature and unless provision is made so that all the accumulated information can be properly digested and analyzed data may be irretrievable lost.
To follow up downloadd materials is responsibility or downloading department. These limitations can form a basis for future investigations in evaluating the showed improving production methods. This is the integral part of control function. Assembly and Erection: Responsibility for assembly and erection of products in assembly manufacturing is almost invariably rested. Work in progress: This follow up the work by checking the process and recording the production accomplished by production line for comparison purpose with preplanned schedules.
It is the duty of follow-up men or expediters to advise the foreman as to the best sequence in which the orders can be run so as the required part in which order to be fabricated and brought it together at right time. Its finding land criticism are of the importance both in execution of current program and both in planning stage of fibre undertaking when the limitations of the processor. IX Inspection: Another major control is inspection.
When all the parts of an available. Material planning is the important activity of materials managements. But there are so many problems awarded with the management of materials. Which require immediate attention of management. Moreover it affects the efficiency of all machines. Appropriate factor of safety should be used in working out latest date of arrival.
In batch manufacturing. For procurement of materials. Bill of material quantity. Overall economy. Working backwards on the schedules the dates on which the difference materials must be in plant. It require the knowledge of. Materials planning for project work can be done in the similar way. Based on the annual forecast. Translation of the sales projections into long term requirements. On the basis of updated production plan adjusted to the latest sales demand to adjust the materials accordingly.
To perform value analysis to determine the intrinsic worth of materials. To project the facilities required for the materials management. Production of Assembly schedule.
Setting up of consumption standards. Manufacturing capacity. Thus the procedure can be developed by which those items required for assembly are available at the time required stocks of these items are not maintained or are maintained at a far lower level. The quantities required are also calculated with he help of bill of materials.. To keep inventories as low as possible. The type and amount of inventory which an organisation should hold will depend upon several aspects including the product manufactured.
Finished Goods Inventories completed products ready for dispatch. Inventories are also classified as: This inventory results because of the transportation time required.
Production Inventories: Items which go into the final products raw materials and bought out components. Miscellaneous Inventories: Which arise out of the above four types of inventory scrap. The Principal Types of Inventories Are: To decide whether to Make or download.
Consumable items etc. In Process Inventories: Work-in-progress items which are partly manufactured and await the next stage in process. Repair and Operating Inventories: Items which do not form a part of final product but are consumed in a prod.
Decoupling Inventories: That large no. These are maintained wherever the user makes or downloads material in larger lots than are needed for his immediate purpose to take the advantages of quantity discounts. Anticipation Inventory: These inventories are maintained to adjust with sudden change in demand e. So these inventories are maintained purely due to the interest of management. In this analysis. Instead of producing more in particular season a producing less during rest of the year.
It is evident from the discussion that to have an healthy organization the pre planning and post-planning activities are to be ground property at the initial stage turning organization. Ten functions of PPC as if ten Commandments to be followed in any manufacturing industry. We cannot. But it appears in one of other forms. Depending upon the nature of production and size of unit. PPC can be considered and value as a heart on the manufacturing of any type and any size.
What are the main benefits of PPC? Issue the statement highlighting the characteristics of good of inter communication. PPC is the governing department and therefore it has been after every function. Therefore to have an healthy organization. This has been depicted precisely in the data sheet. Explain production control as a nervous system? Gov P. PPC department plays a very important and vital role in organization. We observed that in almost all functions. In case. Forecast is made of sales in Rs.
There are 3 major purposes. Direct Survey method. Sales force composite method or Subjective opinion method. By doing so. Projection method. In this method. Jury of Executive opinion. Comparing with established product.
Limited market trial. Here economic. Indirect Survey method. Market Research. Forecasting for a new product is difficult task as no past information is available to predict the future. Related information method. Statistical method. Here opinions of experts are invited about the sale in future.
Through critical analysis of the marketing forces. Forecasting for Established product is explained below. Subjective opinion in this forecast. Based on the historical data. Some times limited selling technique is adopted to product acceptance of the product. At times the product under consideration is comparable to an existing product. Projection of future can be done either by time series Analysis or Correlation. Forecast based on an index in this method which directly varies with the sales volume is found e.
A line drawn through known information is projected into the forecast area to predict what the sales volume will be for future periods. The movements or variations of the dependent variable may be Long period changes Trend.
Time series Analysis: A time series is a chronological data which has some quantity such sales rupees. So sales figures can be compared. The avg. Basic secular trend long term may be linear or non-linear. Methods of Inspection or freehand methods — Once the given time series data have been plotted on a graph paper. Thus these two points determine the position of a trend line. In fact past offers best basis for decision on future action.
We are chiefly concerned with the general tendency of data. Because of since last 25 year it has been found that except for a year or two. S — Seasonal fluctuations C. Then a straight line is drawn. As long as we notice an upward or down word trend movement in the data over the whole period. Time series is a multiplicative model of 4 — components. Basic Trend. The important method of making inference about the future on the basis of what happened in the past is the analysis of time series.
After analysing the time series plant production. Cyclic fluctuations. It is statistical analysis of past demand. Methods of Averages: Here the values are selected of the years which are considered to be the most representative or normal.
The trend line can be extended to estimate future values or intermediate values. There is secular rise in agriculture production in India.. However one must modify the prediction form past data if he.
It is discussed later on. P r od u c ti o n P l a n n in g An d C on t r o l 27 knows that certain events will or will probably happen in future e. Example 1. Determine which statistical technique to try. That is we would forecast that demand will be 99 units for each of the next several months. An Upward Trend with Random Variation. Level Demand With Random Variation. On the other hand events like entry of new competition. In this case demand remains essentially constant but super imposed random variation.
In statistical method we are going to consider following 3 cases. Cyclic Seasonal Demand. From the graph it is clear that it is level demand with random variation about constant value of demand. Evaluate the expected error. Level demand with Random variation.
Make a plot of demand versus time. Make a decision to use the technique under consideration or attempt to find a being one. General Approach To Statistical Forecasting: If we assume that use of statistical methods applied to past data is a realistic of forecasting future demands.
Above approach is demonstrated by solving three examples below. Such considerations should be reflected in new forecast. This can be done by determining the standard error of estimation or standard deviation.
Actual demand n. Forecast is that the demand will be 99 units per month. Same cause system will continue to be operative for some time into the future. Demand data studied for the periods are truly representative of the demand. An upward trend with random variations: Assumptions made: The std.
Example 3: Cyclic Seasonal Demand: Again correctness of our forecast is a function of stability of the cause system. Forecast by a liner forecaster. Values in determinant: These values are shown below.
In some cases.
Decide whether the demand pattern is constant. Observe the nature of graph. Each period. Assume a 3 — year cycle and ignore decimals. The following series relates to the production of a commercial concern of 8 yrs. Other methods of forecasting: Extending the moving avg.
Period of moving avg — period of fluctuations length of cyclic movements in data Generally 3 — yearly. Otherwise all three forecasting functions const. Exponential Smoothing Method: For forecasting. The correctness will be achieved by fraction of the error. Calculation for the M. Chart to verify the control given for forecasting.
We shall new test its validity. An analysis of data alone would generally be insufficient. L by Moving Range Chart: In Ex. We have already checked its validity on M. While controlling.
But action of data or forecaster should be taken only after a consideration of all aspects of the cause system. Actions regarding forecaster are — 1 Revise it including new cause system.? So it is a continuous process. Also new values of MR.
Therefore new forecast the basis of 19 period should be established. By doing so we find out the point for period 19 indicates out of control conditions. We shall use new forecaster in future until we will find evidence for out of control condition in the control chart. LCL should be calculated.
Why it is necessary to revise the forecasts? How do you want of central conditions using is moving range chart. What do you mean by Experimental smoothing forecasting. What is the std. Discuss the imp of sales forecasting for production scheduling. Explain the forecasts based upon the averages.
Explain various types of forecasts. Define production forecasting. Which are the factors influencing on forecast? For the forecasting of seasonal demand which method of forecasting you will suggest and why? What do you mean by forecasting? Brief out the diff.. Application of production forecasting? What is the use of indicators and correlation analysis.
It is difficult to improve because the behaviour of pattern of events difficult to understand and also because control have the emotional overtones associated with love of power and fear of being dominated. The Data Sheets thus aims at establishing a framework for the study and important of planning and Control so that working group which comprises of senior management technicians.
Planning and control are essential activities to the rapid expansion of industry and employment. With appropriate modification to some what extent it can be copied down from other one. It is for this reason that specific Data sheets are reputed to introduce a diagrammatic rotation for recording and studying planning and control inspection to shows that without such a representation any decision and discussion of control is obsortive.
Control requires a particular pattern of activities to operate properly in a dynamic and imperfect world. This is evidently very tedius and complicated matter preparing the production orders but essentially to be maintained. Prepare job cards. To start the control system.
Find out the operation time required. Obtain all specifications like drawings. Determination of sequence of operations using process chart. The Advantages of Process charting: To formulate the production and 1. Process charts: Machine loading charts for work distribution.
Flow process charts — Which represents a more detailed picture. The process chart is usually drawn at the commencement of the investigation. Operation process charts — Which constitute a general layout showing the principle operations and inspections.
To provide basis data for evaluation of performance like schedule. Prepare operation sheet with above data. Check out the available time on machine and prepare schedule of timing of production. It is convenient means of presenting overall information on a factory in limited space and is a record for future reference. Prepare route cards and operation sheet. To authorise.