Information systems mrp. Basics of MRP-MRPII class systems. General characteristics of MRP systems

MRP systems

Material Requirements Planning

In the early 60s. In connection with the growing popularity of computer systems, the idea arose to use their capabilities to plan enterprise activities, including production processes. The need for planning is due to the fact that the bulk of delays in the production process are associated with delays in the receipt of individual components, as a result of which, as a rule, in parallel with a decrease in production efficiency, an excess of materials appears in warehouses that arrived on time or earlier. In addition, due to an imbalance in the supply of components, additional complications arise with taking into account and tracking their condition during the production process, i.e. it was virtually impossible to determine, for example, to which batch a given constituent element belonged in an already assembled finished product.

In order to prevent such problems, a methodology for planning material requirements was developed MRP (Material Requirements Planning). The implementation of a system working according to this methodology is a computer program that allows you to optimally regulate the supply of components to the production process, controlling stocks in the warehouse and the production technology itself. The main task MRP is to ensure the availability of the required quantity of required materials and components at any time within the planning period, along with a possible reduction in fixed inventories. Before describing the structure itself MRP, the basic concepts should be listed.

Materials are the raw materials and individual components that make up the final product. In the future, we will not make any distinction between the concepts of “material” and “component”.

MRP-system, MRP -program - computer program, working according to an algorithm regulated MRP-methodology. It processes data files (input elements) and generates result files based on them.

Material status is the main indicator of the current status of the material: whether the material is in stock, whether it is reserved for other purposes, whether it is present in current orders, or whether an order for it is just planned. Thus, material status uniquely describes the degree to which each material is ready to be put into the production process.

Safety stock material is necessary to maintain the production process in the event of unexpected and unavoidable delays in its supply.

Material requirement V MRP- program represents a certain quantitative unit that reflects the need to order a given material that arose at some point in time during the planning period. There are concepts of total requirement for a material, which reflects the quantity that needs to be released into production, and net requirement, the calculation of which takes into account the availability of all insurance and reserved stocks of a given material. An order in the system is automatically created when a non-zero net requirement arises.

The planning process includes functions for automatically creating draft purchase orders and/or internal production of the necessary materials and components. MRP-the system optimizes the delivery time of components, thereby reducing production costs and increasing its efficiency.

The main advantages of using such a system in production are:

• guaranteeing the availability of the required components and reducing time delays in their delivery, and, consequently, increasing the output of finished products without increasing the number of jobs and workload production equipment;
• reduction of manufacturing defects in the process of assembling finished products, arising from the use of components that do not comply with the technology;
• streamlining of production due to control of the status of materials, which makes it possible to unambiguously track the entire conveyor path, starting from the creation of an order for a given material to its position in the already assembled finished product. Full reliability and efficiency of production accounting is achieved.

primary goal MRP-systems to form, control and, if necessary, change the timing of orders so that all materials required for production arrive simultaneously.

On practice MRP is an information system that can be logically represented using a diagram (Fig. 1). The main information elements are displayed here MRP-systems.

Figure 1 - Input elements and work results MRP-systems

Description of the condition of materials (Inventory Status File) is the main input element MRP-programs. It should reflect the most complete information about all materials necessary for the production of the final product. This element indicates status each material involved in the production process.

Production program (Master Production Schedule) is an optimized time distribution schedule for the production of the required batch of finished products for a planned period or range of periods. First, a trial production program is created, subsequently tested for feasibility by an additional run through CRP-system ( Capacity Requirements Planning), which determines whether there is enough production capacity to implement it. If the production program is considered feasible, then it is automatically formed into the main one and becomes an input element MRP-systems.

This is necessary because the scope of production resource requirements is transparent to MRP- a system that generates a schedule of material requirements based on the production program. However, in the event of unavailability of a number of materials or the impossibility of fulfilling the order plan to maintain a feasible CRP production program, MRP- the system, in turn, indicates the need to make adjustments to it.

List of components of the final product (Bills of Material File) is a list of materials and their quantities required to produce the final product. Thus, each final product has its own list of components. In addition, it contains a description of the structure of the final product, i.e. complete information on assembly technology. It is extremely important to maintain the accuracy of all entries in this element and adjust them accordingly whenever changes are made to the structure and/or manufacturing technology of the final product.

Recall that each of the above input elements is a computer data file used MRP-program. At present MRP-systems are implemented on a wide variety of hardware platforms and are included as modules in most financial and economic systems.

Work cycle MRP consists of the following main stages:

1. The system, analyzing the adopted program, determines the optimal production schedule for the planned period.
2. Materials that are not included in the production program, but are present in current orders, are included in planning as a separate item. At this step, based on the approved production program and orders for components not included in it, the total requirement is calculated for each individual material in accordance with the list of components of the final product.
3. Based on the total requirement, taking into account the current status of the material, the net requirement is calculated for each time period and for each material using the specified formula. If the net requirement for a material is greater than zero, the system automatically creates an order for it.
4. All orders created before the current planning period are reviewed and changes are made if necessary to prevent early deliveries and delays.

Thus, as a result of work MRP-programs a number of changes are made to existing orders and, if necessary, new ones are created to ensure optimal dynamics production process. These changes will automatically modify description of the condition of materials, since the creation, cancellation or modification of an order respectively affects the status of the material to which they relate. As a result of the work MRP- the program creates an order plan for each individual material for the entire planning period, the implementation of which is necessary to support the production program.

Main results MRP-systems are as follows:

1. Order plan (Planned Order Schedule) - determines how much of each material must be ordered at each time period considered during the planning period. The order plan is a guide for further work with suppliers and, in particular, determines the production program for internal production of components, if any.
2. Changes to the order plan (Changes in Planned Orders) - represent modifications to previously planned orders. A number of orders may be cancelled, modified or delayed, or postponed to another period. Also MRP-the system generates some secondary results in the form of reports, the purpose of which is to draw attention to bottlenecks during the planning period, i.e. those periods of time when additional control over current orders is required, as well as to promptly notify about possible system errors that arose during the operation of the program. So, MRP- the system generates the following additional results-reports:
3. Planning bottleneck report- is intended to inform the user in advance of periods of time during the planning period that require special attention and at which external management intervention may be necessary. Typical examples of situations that should be reflected in this report may be unexpectedly late orders for components, excess components in warehouses, etc.
4. Executive report- is the main indicator of correct operation MRP-system and aims to notify the user about critical situations that have arisen during the planning process, such as, for example, the complete depletion of safety stocks for individual components, as well as about all system errors that arise during the work process MRP-programs.
5. Forecast report- represents information used to make forecasts about possible future changes in the volumes and characteristics of manufactured products, obtained as a result of analysis of the current progress of the production process and sales reports. The forecast report can also be used for long-term planning of material requirements.

So using MRP-systems for planning production needs allow you to optimize the time of receipt of each material, thereby significantly reducing warehouse costs and facilitating production accounting.

ERP systems

Due to improved systems MRPII and their further functional expansion, a class of systems appeared ERP(term ERP was introduced by the independent research company Gartner Group in the early 90s). ERP-systems are intended not only for manufacturing enterprises, they also effectively allow you to automate the activities of service companies. ERP is the result of more than forty years of evolution of management and information technologies.

Historically concept ERP became a development of simpler concepts MRP (Material Requirement Planning- Planning of material needs) and MRPII (Manufacturing Resource Planning- Production resource planning). Roughly speaking, ERP is an extension of these two technologies, which allows you to automate not only the operational activities of the company but also financial activities, accounting, personnel, payroll accounting, etc. Used in ERP-systems, software tools allow for production planning, modeling the flow of orders and assessing the possibility of their implementation in services and departments of the enterprise, linking it with sales.

ERP is a methodology that manages and plans the distribution of all available enterprise resources that are necessary to organize the work of the so-called logistics pipeline, which includes procurement, production, and accounting for the execution of customer orders. Application ERP-systems are widespread in many areas of business, in particular, in various types of production, distribution, and service provision. Most manufacturers have standard solutions customized for common types of businesses.

The term " ERP system» ( Enterprise Resource Planning- Enterprise resource management) can be used in two meanings. Firstly, This - information system for identifying and planning all enterprise resources that are necessary for sales, production, purchasing and accounting in the process of fulfilling customer orders. Secondly(in a more general context), this is - methodology for effective planning and management of all enterprise resources that are necessary for sales, production, purchasing and accounting for the execution of customer orders in the areas of production, distribution and service provision.

Abbreviation ERP used to refer to complex enterprise management systems. Key term ERP is Enterprise– Enterprise, and only then - resource planning. True purpose ERP- in the integration of all departments and functions of the company into a single computer system that can serve all the specific needs of individual departments.

The hardest thing is to build unified system, which will serve all the requests of employees of the financial department, and, at the same time, will please the HR department, the warehouse, and other departments. Each of these departments usually has its own computer system, optimized for its specific work needs. ERP combines them all into one integrated program that works with a single database, so that all departments can more easily share information and communicate with each other. This integrated approach promises to be very rewarding if companies can get the system installed correctly.

Take order processing for example. Typically, when a customer places an order, he begins a long journey from one filing folder to another. At the same time, information on the order is simultaneously “driven” into one computer system, then into another. This unhurried journey leads to delays in the execution of orders and their loss, and also causes errors when entering information multiple times. different systems. Meanwhile, at the right moment, no one in the company can truly say what the real status of the order is, because the front office employee cannot look into the warehouse computers and say whether the goods have already been shipped or not. And the angry customer only hears: “Please call the warehouse!”

ERP replaces old disparate computer systems for finance, personnel management, production control, logistics, and warehouse with one unified system consisting of software modules that repeat the functionality of old systems. Programs serving finance, production or warehouse are now linked together, and from one department you can look into the information of another. ERP-the systems of most suppliers are quite flexible and easily customizable; they can be installed in modules without purchasing the entire package at once. For example, many companies purchase only financial or HR modules at first, leaving the automation of other functions for the future.

ERP- the system automates the procedures that form business processes. For example, fulfilling a customer order: accepting the order, placing it, shipping from the warehouse, delivery, issuing an invoice, receiving payment. ERP-the system “picks up” the customer’s order and serves as a kind of road map along which various steps along the path of order execution are automated. When the front office representative enters a customer order into ERP-system, he has access to all the information necessary to launch a fulfillment order. For example, he immediately gets access to the client’s credit rating and the history of his orders from the financial module, learns about the availability of goods from the warehouse module and about the schedule of shipment of goods from the logistics module.

Employees working in different departments see the same information and can update it in their section. When one department completes an order, the order is automatically forwarded to another department within the system itself. To find out where the order was at any time, you only need to log in and track the order. Because the entire process is now transparent, customer orders are processed faster and with fewer errors than before. The same thing happens with other important processes, for example, creating financial reports, payroll, etc.

That's the role ERP-systems are ideal. The reality is somewhat harsher. Let's return to the same paper folders. This process may not be effective, but it is simple and familiar. The accounting department does its job, the warehouse does its job, and if something behind the walls of the department is wrong, it’s someone else’s problem. With the arrival ERP everything changes: the salesperson is no longer a typist who just types the customer's name and presses the “Enter” key. Screen ERP-system turns him into a businessman. The salesperson moves from the customer's credit history to the warehouse situation. Will the client pay on time? Will we be able to ship on time? Sellers have never made such decisions before, and customers depend on these decisions, and other divisions of the company depend on them. And it's not just the salespeople who have to wake up - the people in the warehouse, who previously kept the entire list of goods in their heads or on scraps of paper, now have to enter it into the computer. If they don't do this regularly and quickly, the salesperson will tell the customer the item is out of stock, the customer will go to another supplier, and the company will lose money.

Responsibility, reporting and unified communications Never before have they been tested so harshly. People don't like change, but ERP requires a change in their working style. This is why it is so difficult to assess the effect of ERP. It's not so much the software that's valuable, but the changes companies must make in the way they do business. If you simply install new software without changing how it works, you may not see any effect at all. On the contrary, new software will slow you down - you will replace the old program that everyone knows with a new one that no one knows.

Managment structure

ERP-systems are more focused on working with financial information to solve problems of managing large corporations with geographically dispersed resources. This includes everything that is necessary to obtain resources, manufacture products, transport them and pay for customer orders. In addition to the listed functional requirements in ERP New approaches to the use of graphics, the use of relational databases, CASE technologies for their development, the architecture of client-server computer systems and their implementation as open systems have also been implemented.

Type systems ERP are replenished with the following functional modules - demand forecasting, project management, cost management, product composition management, maintaining technological information. HR management modules and financial activities enterprises.

Functions of ERP systems

In recent decades industrial production became more complex, customer requirements for product quality and service levels grew, and the time to bring new products to market decreased.

In recent decades, industrial production has become more complex, customer demands for product quality and service levels have increased, and the time to bring new products to market has decreased. There is a need to improve management methodology and technology. It was necessary, on the one hand, to systematize existing approaches, and on the other, to accelerate the solution of the problems facing the enterprise. There was a need to develop appropriate standards. One of them was the enterprise resource planning standard - MRP II.

Where it all began. MRP I

At the first stage of development of the standard, the following task was solved: to form a calendar program for the need for components, raw materials and supplies, parts and assembly units ah based on the registered need for finished products, taking into account the available warehouse stock. In the early 60s, this problem found a computer solution called MRP (Material Requirements Planning) - material requirements planning. The term was coined by Orlicki. It should be noted that this approach was used in several enterprises in Europe before the outbreak of World War II, but not in a computer version. Orlitzky was the first to realize the capabilities of computer technology for solving control problems industrial reserves. The diagram for solving the problem is shown in Fig. 1 from the work of Robin Goodfellow.

Let us present the input data for the task.

1 Data on the need for products of independent demand: interest in obtaining certain product items is shown directly by the consumer of the products of the enterprise to which these products are shipped. Examples of such product items can be finished products, spare parts, semi-finished products and components sold externally, etc. The need can be represented either by a sales forecast, or by existing customer orders, or by both at the same time. Information on sales forecasts and sales orders is the basis for the formation of the main calendar plan production (Master Production Schedule, MPS), covering all product items included in the production plan. MPS is formed in both volumetric and calendar versions. In domestic terminology, the corresponding document is called “Main Production Schedule”.

2 Data on inventories of products, assembly units and materials, as well as information on open orders. When solving the problem, not only the stocks of finished products shipped externally and raw materials purchased from suppliers are taken into account, but also the stocks of product items at all intermediate stages of product production (semi-finished products of own manufacture, assembly units, components, etc.).

3 Data on the composition of products and consumption rates of raw materials, materials and components per unit of measurement of finished products. In MRP theory, this information is called BOM (Bill of Material), which is an analogue of the domestic term “specification”.

Based on this information, a description of the enterprise’s needs for produced and purchased product items is formed, expressed in the form of a calendar plan. MRP generates two arrays of messages: planned orders and recommendations (action messages).

Planned orders provide the order size, release date, and due date as the result of MRP work when MRP meets net requirements. Recommendations are the output of the system and determine the type of action required to resolve current or potential problems. Examples of recommendations in the MRP system include “start order”, “reschedule order”, “cancel order”.

A clear disadvantage on at this stage development of MRP technology, it was impossible to update the final information obtained during MRP work, i.e., to adapt to changes that arise in the case of open orders. Because of this, the first MRP systems, as noted by Landwater and Gray, were called “launch and forget.” However, the ability to update is very important because the environment in which MRP is used is highly dynamic, and frequent changes in order sizes and lead times are not uncommon. Hence the need to monitor the current state of affairs.

It should be taken into account that at that time the batch type of information processing at remote computing centers (cluster or corporate) prevailed. Interactive technologies have not yet been developed, and the analysis of “what will happen if ...” has practically not been carried out. In essence, MRP simply recorded the situation in an “unfolded” form.

Note that MRP technology is sometimes called MRP I.

Moving to Resource Planning

It is clear that as data processing tools have improved, the inherent limitations of MRP are no longer satisfactory to managers and planners. Therefore, the next step was to implement the ability to analyze production capacity utilization and take into account production resource limitations. This technology is known as CRP (Capacity Requirements Planning). It is shown in Fig. 2.

For the CRP mechanism to work, three sets of initial data are required.

1 Manufacturing scheduling (MPS) data containing information about production orders. They are also the starting point for MRP. It is worth noting that launching CRP is possible only after MRP has been processed, because the source data for CRP is also the results of MRP work in the form of planned orders for item items of dependent demand, and not just for item items of independent demand.

2 Work center data. A work center is a group of interchangeable equipment located at a local production site. For the purposes of capacity requirement planning (CRP) and detailed scheduling, it can be considered as one production unit. For CRP to work, it is necessary to first create a working calendar of work centers in order to calculate the available production capacity.

3 Data on technological routes for manufacturing item items. These documents indicate all the information about the procedure for carrying out technological operations and their characteristics (technological times, personnel, other information). This data array, together with the first one, forms a work center load plan.

CRP informs of any discrepancies between planned load and available capacity, allowing necessary regulatory actions to be taken. In this case, each manufactured product is assigned a corresponding technological route with a description of the resources required for each of its operations at each work center. It should be noted that CRP does not optimize loading, performing only calculation functions according to a predetermined production program as described regulatory information. Both MRP and CRP are planning mechanisms that allow obtaining a correct and realistic production schedule based on the experience and knowledge of decision makers. It can be noted that the established MRP/CRP technology, with sufficient computing power, allows, in fact, to simulate the situation.

Results-Based Dynamic Planning

The next step in the development of the MRP standard after MRP/CRP was the creation of the Closed-loop MRP technology, proposed in the late 70s by Oliver White, George Plossl and others. The idea behind this enhancement to MRP technology is to create a closed loop by creating feedback loops that improve state tracking. production system. The additional implementation of monitoring the implementation of the supply plan and production operations made it possible to remove the restrictions on the degree of reliability of the planning result previously inherent in MRP I, which existed due to the inability to track the status of open orders. With the addition of these functions to MRP I/CRP, the “Closed Loop MRP” standard was formed. The difference between MRP I/CRP and Closed-loop MRP is well illustrated by the diagram in Fig. 3.

Looking at Fig. 3, we will see that in the case of the “Closed Loop MRP” technology, only operations related to supply and production are involved in the planning process, and the processes of distribution (sales) and financial accounting are not involved by the technology. Sales & Operations Planning is not included in the MRP I/CRP circuit and is given only to illustrate the connection of MRP I/CRP with higher planning levels.

Enterprise resource planning

The MRP II (Manufacturing Resource Planning) standard has enabled the development of application-oriented planning technology information systems enterprises, outlining the full outline of the tasks of managing an industrial enterprise at the operational level. The most important function of MRP II is to provide all the necessary information to those who make decisions in the field of financial management. MRP I informs you about the timing of purchase orders, helping you plan payments to suppliers. MRP I / CRP provides information on the quantity of the main production staff, hourly level tariff rates and time standards for performing technological operations (in the description of technological routes), possible overtime work etc. All this is necessary for the enterprise to accept payment obligations wages. Finally, MRP II reports the volume and timing of product delivery to customers, which allows for forecasting Money. However, it should be noted that in order to ensure the reliability of the results of MRP II, it is necessary to ensure the accuracy and timeliness of input information of a regulatory and operational nature.

Business planning here is still not integral part standard, but provides initial information for making planning decisions at a lower level, which consistently refine the plan by expanding and detailing planning objects, approaching the planning horizon, reducing the planning interval, and also moving from cost units of measurement to natural ones. Developed detailed plans to be executed receive value expression through product costing, sales accounting, supply and production operations. The calculated actual costs are compared with the planned (or standard) ones, and deviations serve as the basis for acceptance management decisions related to the following planning periods. The structure of the planning mechanism in the MRP II standard is shown in Fig. 4 .

One of the main reasons that MRP has been readily adopted as a manufacturing management methodology is its appeal to the power of computer technology to store, process and provide access to large amounts of data for the purpose of effective management enterprise. It helps coordinate the activities of various departments of the enterprise in performing their inherent functions. Therefore, the appeal of MRP lies not only in its decision support, but also, more importantly, in its integration role for manufacturing enterprises.

Characterizing MRP II as a whole, we can say that its mechanism is based on three basic principles: hierarchy, interactivity, integration.

Hierarchy means dividing planning into levels corresponding to the areas of responsibility of different levels of the enterprise’s management ladder. This means all levels, from top management planning sales and operations, to foremen in the workshops and on production sites, performing the functions of dispatching production work orders and making operational decisions on workload loading, managing work order priorities, and generating reporting data on completed orders. Enterprise plans are developed from the top down while providing a robust feedback mechanism.

The interactivity of systems based on the MRP II standard is ensured by the modeling block embedded in it. There is the possibility of “playing out” probable situations in order to study their impact on the results of the enterprise as a whole or its structural divisions in particular. Note that this opportunity is available at various levels of the hierarchy of planning decisions. Interactivity is supported by modern computer technologies that provide remote access to databases from the workplaces of specialists in different subject areas. Thus, computing power is “placed” next to the knowledge and experience of enterprise specialists.

Integration is ensured by the unification of all the main functional areas of the enterprise at the operational level (within a planning horizon of up to one year) related to material and financial flows in the enterprise. MRP II covers enterprise functions such as production planning, production supply, product sales, production plan execution, cost accounting, inventory control, demand management, etc.

Characteristics of MRP II modules

Sales & Operations Planning. The sales and operations plan (or sales and production plan) serves two main purposes within a functioning MRP II system. The first is to be a key link between the strategic and business planning process and the company's detailed planning and execution system. The second purpose is that the adopted sales and operations plan is the regulator of all other plans and schedules. In essence, this is a budget that is set by top management for the main production schedule, which in turn forms all subsequent schedules in the hierarchy.

Demand Management. Demand management connects the following functions of an enterprise: demand forecasting, working with customer orders, distribution, movement of materials and assembly units between the company’s production sites. Thus, demand management is an integral part of the overall planning and scheduling process.

Master Production Schedule. This module fixes the production plan, as a rule, based on the nomenclature items of independent demand, i.e. “what to produce, when to produce, how much to produce.” All other schedules in MRP are based on it and are formed by “unfolding” - from the need for finished products to the need for components and materials through the described product structures.

Material Requirements Planning. This module is a calculation mechanism necessary for calculating the need for all product items that do not represent products of independent demand, the enterprise’s need for which can be calculated based on demand data (in the form of forecasts or orders) for products of dependent demand, i.e. for those that the company sells to counterparties. These include materials, components, parts, etc. Historically, this was the first module developed within MRP II systems, and subsequent functionality was “layered” on top of it. We can say that this module is the core of any MRP II system.

Bill of Material Subsystem. This module within the MRP system is supporting, containing regulatory and reference information necessary for correct planning. The BOM subsystem defines the relationships between product items within product structures and is based on the Bill of Materials (BOM).

Inventory Transaction Subsystem. This subsystem is necessary to keep data on inventory items up to date and is based on a set of types of inventory transactions that are previously described and entail predetermined consequences.

Subsystem of planned receipts for open orders (Scheduled Receipts Subsystem). The subsystem of planned receipts for open orders is used to work (adding, deleting, changing) with orders, the production and purchase of which has begun, but has not yet been completed or closed. Depending on whether a particular item is included in the master production schedule or is entirely controlled at the material requirements planning (MRP) level, the module that consumes the information provided by the subsystem changes.

Operational production management (Shop Floor Control or Production Activity Control), or, in other words, planning and dispatching the work of the workshop (Shop Scheduling and Dispatching). We can say that this module defines a way to discuss priorities between planners and shop floor personnel. It allows you to see the work schedule of the workshop on production orders from the perspective of both the workshop and the work center and production operations, as well as track its actual implementation.

Capacity Requirements Planning. This module allows you to present a picture of the work center load according to the production program that was adopted at the level of the master production schedule and went through the calculation of the need for manufactured components, performed by MRP. The module allows you to predict possible capacity problems and resolve them in a timely manner, i.e., avoid encountering them when changes to the schedule are impossible or expensive. Please note that CRP does not attempt to resolve identified problems, but leaves them to the discretion of staff.

Control of input/output material flow (Input/Output Control). The module is designed to monitor the execution of the production capacity utilization plan developed at the CRP level. The relationship between these two modules is very similar to the relationship between MRP and production dispatching, where MRP sets the priorities for production tasks, and shop floor planning and dispatch help ensure that those priorities are met.

The input/output material flow control module allows you to evaluate whether the plan for loading production capacity has been fulfilled or not, since it controls the input and output flows of tasks directed to work centers, as well as the length of the queue to work centers, measured in hours of operation of the work center.

Supply management (Purchasing). The module is designed to monitor the implementation of the procurement plan generated by the MRP and approved by the decision maker, as well as the planning and execution of purchases not related to the MRP module itself. Thus, we can say that MRP plans the timing and parameters of purchase requisitions, and this module helps to control the implementation of these requisitions by converting them into purchase orders.

Distribution Resource Planning. The module is designed to provide planning in the case where an enterprise has a geographically distributed structure with several sites remote from each other. In this case, it is necessary to describe the distribution network, indicating all the essential parameters of this network (delivery time, work calendar of various nodes of this network, mode and cost of transportation, etc.). We can say that DRP is a kind of MRP for the distribution network. In other words, DRP links several MRP sites together. In this case, both production and trading divisions of the company can be considered as sites (for example, a remote warehouse that ships products to customers in another region).

Tooling (Tooling or Tool Planning and Control). For some companies scheduling Instrumental support for production is no less important than scheduling the need for materials and production capacity. Structurally, the tool support subsystem may be similar to the MRP/CRP system, coupled with the subsystems that support them (inventory operations, planned receipts, product specifications, etc.). It is technically possible to implement one of two approaches: either fully integrate the tooling subsystem with MRP/CRP at the level of database files, or position it separately from MRP/CRP with an appropriate interface between these modules.

Interface with financial planning(Financial Planning Interfaces). MRP II provides the information needed to perform financial planning, but the actual financial analysis and planning functions are not included in MRP II. This is why they talk about an interface with financial planning. MRP II provides detailed and fairly accurate information of the following nature:

• the projected amount of reserves and their cost;
• expenditure of funds (purchase of materials, labor costs, variable overhead costs);
• receiving funds;
• distribution of fixed overhead costs (indirect).

In companies that do not use MRP, this kind of information, according to D. Landwater and K. Gray, is usually difficult to obtain in the required period of time and with the required accuracy. In this case financial forecasts often based on data from reporting periods and historical proportions between indicators. Unfortunately, this approach fails precisely when an assessment of the factors influencing the result is needed most—at the moment the situation changes.

With MRP II, information for financial planning is extracted directly from the operating production system. The financial planning interface in MRP II converts the plan, expressed in physical and time units, into cost units. Thus, in MRP II, financial forecasts are based on detailed information about item items, orders, etc., expanding this information through the use of cost data.

Simulation. The MRP II system is a detailed and accurate model of a manufacturing business. Consequently, it becomes possible to establish how changes in event parameters will affect the results of the enterprise. MRP II helps answer questions like “what would happen if...”.

Performance Measurement. The MRP II system must have criteria for assessing the efficiency of the enterprise, that is, a system of indicators is needed by which the management of the enterprise will judge the success of the company as a whole and its individual divisions. A formalized performance assessment program (and this applies to MRP II and any other management system) will help:

• establishing formal, objective criteria as opposed to informal feelings and guesses;
• developing standards for comparison with other companies;
• forming goals and determining the degree of their achievement;
• identifying problems and establishing procedures for resolving them, as well as monitoring the improvement of the company’s activities.

Enterprise resource planning. The last step in the evolution of resource planning systems (the 90s) is known as Enterprise Resource Planning (ERP), which, according to N. Guyver, is more advanced than MRP II.

ERP systems consist of a large number of software modules that can be purchased separately and help manage many activities in different functional areas of the business. Such modules include modules for sales and distribution, financial accounting, financial controlling, production planning (including MRP and CRP), management of fixed assets, personnel, materials, quality, projects, operation of production facilities (Plant Maintenance), operational management execution of production orders (Workflow), as well as industry solutions (Industry Solutions). ERP systems require significant effort and large investments, and sometimes changes in some business processes in order to comply software, and may have an implementation cycle of several years.

Literature

More details on the issues discussed in the article can be found in the book by D. A. Gavrilov, “Production Management Based on the MRP II Standard,” published by the Peter Publishing House.

Basic MRP Assumptions

1. operations are carried out within the boundaries of one production site, i.e. a geographically distributed structure of enterprises is not supported.
2. Production resources are unlimited, so MRP does not care about their sufficiency to fulfill the formed plan.

"Closed Loop MRP"

A system built around materials requirements planning (MRP), which includes additional planning functions, namely production planning (aggregate planning), development of a master production schedule (Master Production Scheduling) and capacity requirements planning ( Capacity Requirements Planning). Once the above planning phases have been completed and the plans have been accepted as realistic and achievable, execution of the plans begins. This includes production management functions such as Input-Output (Capacity) Measurement, generation of detailed schedules and dispatching, as well as reporting on expected delays from plant and supplier schedules, generation of supplier schedules etc. The term "closed loop" means that these elements are not only included in the overall system, but there is feedback from the execution functions so that planning is always correct.

I continue to post definitions and requirements for systems.

4.MRP, CRP and MRP II concepts

4.1.Definition of MRP and MRP II. History of development

The history of the development of this class of systems dates back to the 1950s, when the concept of MRP (Material Requirement Planning) was developed. But at that time, such systems were not widespread due to the lack of necessary available computing resources. One of the ideologists of this class of systems was Joseph Orlisky, who defined them as “Material requirements planning systems consisting of a number of logically related procedures, decisive rules and requirements that translate the production schedule into a “chain of requirements”, synchronized in time, and planned “coverages.” » these requirements for each unit of inventory of components needed to meet the production schedule. An MRP system reschedules the sequence of requirements and coverages as a result of changes in either the production schedule, inventory structure, or product attributes.”

In 1975, Oliver Wight and George Plossl improved the MRP standard into MRP II. The main difference was that now planning took place not only taking into account restrictions on inventories and production capacity, but also on finances.

4.2.MRP II input data

Main input data in the MRP system:

Product data including BOM and routing

Requirements data generated by MPS, as well as data from the sales system and project management system

Inventory data, including existing inventory, production orders already placed, and planned purchase orders

As a result of the planning process, production orders (shop assignments), purchase orders in the logistics system and exception messages are generated, which indicate that problems arose during the planning process that could not be resolved or, conversely, When solving problems, changes to already made plans are required.

The requirements planning process uses the item parameters discussed earlier (item type, order policy, ordering system, and ordering method) to determine whether an item should be ordered by MRP, in what quantity, under what order policy.

Typically, demand forecasting is part of the Volume Scheduling function, using the “product history” for statistical analysis and forecasting the movement of goods on the market. If a particular business does not use the Volume Scheduling process, sales can be forecast for the MRP components based on sales budgets (that is, sales targets derived from any consideration). In some cases (spare parts, for example), sales can be forecast for MRP components based on the sales budget, even if the demand forecasting process in the Quantity Scheduling system is used for finished products. A typical example of such a situation is, for example, the replacement of one product within product group others (for example laser printer to a printer of a different brand, or replacing a 500GB hard drive as standard with a computer. for 1TB.)

Requirements for MRP components resulting from business forecasts will be added to any existing requirements for those same components derived from scheduling or project management functions.

4.3.MRP II Processes

The demand planning function in the MRP (II) system includes three processes:

Material Requirements Planning (MRP)

Capacity Requirements Planning (CRP)

Statistical Inventory Control (SIC)

MRP II assumes the possibility of automatically obtaining information from “corresponding” subsystems. That is why it is impossible to call a non-integrated system that implements MRP I, CRP, SIC and MPS in the form of automated workstations an “MRP II class” system. Based on the analysis of the need for certain types of data and from the subsystems in which such data is usually generated, it is possible to draw up a list of functional blocks that should consist of software, claiming to be an "MRP II system". At the same time, it is apparently incorrect to call these blocks modules, since the latter term implies the possibility of autonomous existence of each of them (each module). In this case, this is not always possible and, as a rule, impractical.

4.4.Standard blocks of an MRP II class software product

The main blocks of MRP II class systems, as defined by APICS (American Production and Inventory Control Society), are:

Forecasting

Sales management

Volume scheduling - production planning

Bill of Materials (BOM) and Product Breakdown Management

Inventory Management

MRP - materials requirements planning

CRP - capacity requirement planning

Shop management (possibly - various modules for serial, custom, project or continuous production)

Finance and accounting

The financial analysis

The absence of any block in the software product means it is impossible (within the framework of correct marketing, of course) to characterize it as an MRP II system. However, this list does not say anything about the “depth” of elaboration of individual blocks. Accordingly, if a software product allows you to implement only one forecasting method (for example, averaging based on historical data), or only one workshop control unit (for example, only mass production), then such a product will still have the right to be called MRP II. Moreover, nothing can be said about the quality of the financial subsystem, or about the ability to support warehouse management of a certain type.

4.5.Main objectives of MRP

The main purpose of using MRP is:

Satisfying production needs for materials, components and products to plan production and delivery to consumers;

Maintaining low inventory levels;

Planning production operations, delivery schedules, purchasing operations.

The MRP system allows you to determine how much and in what time frame it is necessary to produce final products. The system then determines the time and quantities required material resources to meet production schedule needs.

The MRP process "explodes" the BOM of each item planned in the MPS down to the lowest level, further using required lead times data to estimate the time required to produce or acquire each item included in the BOM, including components and assemblies. The Russian term “explosion” is associated with the name of the components of the structure of the finished product used in mechanical engineering, where this procedure was first used: product - assemblies - components and materials. Thus, explosion is “going down” through the structure of product components to calculate the need for raw materials and supplies necessary for their production.

The demand for each low-level node (or semi-finished product) is summed up across the entire BOM (that is, if the same low-level product is contained on several branches of the BOM, then the total demand for all branches is calculated). The result is a materials requirements plan (MRP), which shows the need for each semi-finished product, component, raw material and materials in each planning interval.

An essential condition for the effective operation of this process in MRP II systems is that in addition to the actual calculation of the need, the system distributes this need over time, taking into account planned receipts and existing stocks, as a result, for each product the time for its launch into production and/or formation period is determined order to the supplier in order to meet the demand at the right time. The logic of execution and, accordingly, the need for raw materials and materials significantly depend on the established policy for implementing the planning process.

MRP Terminology

LLC - low-level-code; the lowest level at which a component appears in the bill of materials (BOM)

Item - any item of inventory, and sometimes a special BOM component

LT (lead time - delay time) - time from the moment the order is issued until the goods are received

Gross requirements (general need) - the need for a product (product) for the planning period (excluding cash reserves, etc.)

Planned receipts

Products for which a production task has already been generated and the production date is known

Confirmed orders

Projected on hand ("on hand" - estimated availability) - estimated stock at the end of the period

Net requirements (net - "net" need) - net need determined after calculating the expected availability

Planned order receipts - net demand after conversion into production orders

Planned order releases (planned launch) - the launch time of production tasks, formed taking into account delay times

In addition to generating a planned production order and a planned purchase order, the MRP process can also generate exceptions for an existing production or purchase order that may be needed when changes are made to the planned requirement. For example, if the demand for some components on an existing production order or purchase order has changed, the MRP process will recommend replacing (changing) the quantity on the existing order to account for the additional (or reduced) demand. Recommended changes may include increasing, decreasing, eliminating, or reordering (by time or priority) scheduled orders.

The MRP process compares the total demand for each item in each time period (or planning interval) with the expected receipt of the same item in the same time interval. Expected receipt is calculated by adding the planned quantity of products in production and the planned acquisition in each time interval to the quantity warehouse stocks at the beginning of the period. This expected receipt is based on "economic" inventory (meaning the network actually uses a forecast for the receipt of goods), and not just physical inventory.

If the total demand for any item in any time interval exceeds the expected supply, MRP uses a two-step process to establish compliance. The first step involves moving or increasing (or both) existing production and purchase orders. If no orders (yet) exist, or existing orders cannot be changed, then a new production order and a purchase order will be planned to satisfy the new (increased) demand.

If demand for an item has decreased, MRP will first propose reducing the quantity on an existing production order or purchase order, propose to hold orders, or cancel orders. Planned stock movements must be made available to analytical work for any product, component or assembly.

Typically, MRP requirements are generated by the Master Planning function (MPS) for components and assemblies whose demand quantities are forecast, and by the requirements planning function for components that are dependent on sales orders. In addition, sales forecasts can also be entered for MRP components.

4.6.Statistical Inventory Control (SIC)

Although the requirements for most raw materials, components and assemblies in the make-to-order model are planned by either MPS or MRP, some requirements for components or materials can be planned based on the SIC process. SIC components are typically low-cost raw materials or assemblies that are used in many components of a finished product, such as hardware in a computer or adhesive in furniture. These components are typically produced or purchased based on a "SIC ordering policy", a type of system for maintaining minimum inventory levels.

Inventory functions are usually considered as part of logistics, more often than as part of the production process, although in large industries the logistics and production components are often very closely related, especially their implementation in the intra-shop management function. Regardless of how the inventory function is defined in your business, its basic objectives remain the same and boil down to statistical inventory control.

In principle, both purchased and manufactured product types can be assigned to the SIC ordering system. Whenever the SIC order system's "economic inventory level" falls below the reorder point defined in the item master record, the SIC system schedules the production, or purchase, of additional quantities of the item. IN modern systems It is possible to determine the safety stock for each warehouse separately, which allows for independent management of inventory replenishment in warehouses. "Economic inventory level" is calculated by adding the available "on order" inventory and the "available" inventory "on hand" inventory, and subtracting the reserved inventory inventory.

The quantity of items that will be purchased or produced depends on the order method assigned to the item. SIC ordering system components are typically assigned to one of three ordering methods:

Economic quantity (magnitude) of the order

Fixed order quantity (value)

Replenishment to maximum inventory level

Typically in Russia, mixed ordering methods are used, in which the system prompts the required quantity, and the purchasing department makes a decision “not below demand” or “close to demand.” To effectively solve this problem, the system must allow you to quickly analyze the “sources” of a purchase order, which is implemented, for example, in the SyteLine system, but this capability may not be available in “standard systems.”

SIC planned orders can be based on total warehouse stocks or can be generated separately for each warehouse. If the item type is manufactured, the SIC generation process results in a planned production order. If the item type is purchased, the result is a planned Purchase Order. As with other types of planning, the resulting planned production order and purchase order can be changed if desired or necessary.

If desired changes have been made to the SIC planned production orders and purchase order, the planned orders must be confirmed, then transferred to executive functions before they can be processed further. As with MRP planned orders, SIC planned orders can be confirmed manually or automatically and can be transferred manually or automatically. The SIC-generated production order is transferred to the shop floor management system, the SIC-generated purchase order is transferred to the purchasing system.

The inventory module of an MRP system typically includes an extensive set of inventory analysis tools for the SIC ordering system components. These types of systems include sessions for ABC motion analysis, slow motion analysis, inventory valuation, etc.

4.7 Capacity requirement planning (CRP)

The CRP process involves calculating the time-structured capacity requirements for each work center required to produce the components, assemblies, and finished goods planned in the material requirements plan (MRP). The process is similar to the MRP process, except that routing information for each item is used instead of BOM. The CRP process only affects components of the product structure designated as manufactured and does not affect purchased components.

The CRP process calculates required capacity using work center capacity, routing data, and the work center calendar to calculate available production capacity. The production capacity requirement is based on the planned production order generated by MPS, MRP and SIC. The CRP process also takes into account production orders that have been submitted to shop floor management but have not yet been completed.

In standard systems, the input data for planning the need for production capacity is the “planned launch” data of MRP - that is, the formed need for manufactured components and semi-finished products. Thus, it can only be implemented after calculating the material requirements.

The result of the work is the so-called “load profile”, which determines the capacity required to fulfill the plan for each work center.

If productivity is found to be insufficient to meet MRP requirements, then either the MRP requirement must be changed or productivity must be increased. It may be possible to change the demand predicted by MRP by starting production of some of the output earlier than previously planned in order to use spare capacity at an earlier time interval. It may also be possible to increase productivity through overtime, adding additional shifts, subcontracting, etc.

CRP Terminology

Load profile - loading profile - compares demand with planned (available) capacity

Capacity - performance - including load and efficiency

Efficiency - efficiency - possible loading in comparison with the passport (not to be confused with loading)

Load percent - load percentage - the ratio of load to performance

If all available capacity improvements are not sufficient to meet MRP requirements, then it may be necessary to redesign the MPS. In the simplest business models of MRP systems, the productivity of work centers is usually considered unlimited and such problems do not arise, however, since real productivity is always limited, modern MRP systems provide the ability to plan in conditions of limited resources.

In an MRP system, the CRP function calculates the production capacity required to produce the planned production order generated by MPS, MRP, SIC.

MPS and MRP are used to generate a planned production order before the CRP process calculates the required throughput. The planned production order generated by these functions provides the main input data for the CRP process. If components are assigned to the SIC ordering system, the planned production order for replenishment of inventory (semi-finished products) own production) must also be generated before running the CRP. Capacity planning must be completed before the planned production order generated by MPS, MRP, and SIC can be released to shop floor control.

Another important function of CRP is to analyze the financial implications of planned production. In addition to calculating required productivity, the CRP process also performs financial analysis of the backlog and production order. Financial analysis in CRP uses information on purchasing, sales, inventory, MPS, and demand planning.

Financial information analyzed by the CRP process includes available inventory, open purchase orders, open sales orders, open production orders, and planned orders. Financial analysis includes all planned sales inventory movements, MPS, requirements planning, and planned requirements generated by the project management system.

Interaction with the financial subsystem.

After completing the MRP calculation, or SIC process, a planned production or purchase order appears. In the "planned" state, orders do not affect the actual financial position of the company. Orders may still be changed (substituted), added or deleted.

Once the planned purchase order has been confirmed and converted into a "real" purchase order, financial position the company is expected to change as debts to the supplier will increase from now on. Warehouse inventories will also increase (from the expected delivery date).

Based on MRP or SIC calculation required to cover planned costs, working capital should be increased. This means that either cash, bank or trade credits are needed to finance the purchase (increase) of inventories, work in progress and finished goods inventories. Depending on the financial condition and company policies, components of these types can be paid for from company capital or loans. Unpaid (up to a certain point) bills payable or bank loans are also considered as a specific type of loans.

Financial connections to MRP and SIC in the MRP system are indirect. The requirements planning process carries out financial transactions resulting from the execution of a planned acquisition or production order.

4.8.Required MRP data

Master production schedule

The production schedule is formed in conditions of independent demand. The system does not contain any automation tools for creating a production schedule. The plan is formed manually and must be implementable, that is, consistent with demand and financial plan. But at the same time, a list of key resources is compiled for each unit of finished product. It reflects the shortage of resources and possible compensation for this deficiency. This monitoring of resource requirements and matching them with available system resources must be done continuously. The production schedule itself also requires constant review. To eliminate the lack of revision of plans, the production schedule is divided into periods. In the first period of modification production plan not allowed. In the second period, modifications are allowed, and the production plan must be coordinated with the available key resources. The further a period is from the present moment, the less certain and more dynamic the information becomes.

Specifications

A bill of material (BOM) is a list of components and materials needed to produce a finished product, indicating the quantity and planned production or delivery time. In this way, the finished product is described down to the materials and components.

Inventory and open order data

Taking into account the specifications, the complete component requirements are calculated. These components must be ready when the "parent" node starts. The MRP algorithm processes the BOM in the same order as the levels of the BOM tree, and based on the master production schedule, the total requirements for finished units are calculated.

4.9.MRP Output

Output data includes primary and secondary reports that perform an auxiliary function.

Planned orders – a schedule broken down by planning periods, which contains the time and amount of the future order.

Permission to execute planned orders, i.e. materials are released into production: the remaining inventory is recalculated taking into account the costs of materials, and then the materials are sent directly to production, i.e. production orders are issued.

Changes to planned orders include changes to the order date or quantity, as well as order cancellations.

Plan performance monitoring reports show deviations from plans and also contain information necessary to calculate production costs.

Planning reports include existing supply contracts, purchase commitments, and other data that can be used to estimate future production material requirements.

Exception reports highlight major inconsistencies and detected errors in data and reporting.

The information for this article was taken from open sources, I do not claim authorship, I just tried to combine information from different sources into definitions that can be used to classify systems and find out whether the system corresponds to a given class.

I hope this series of articles will be useful.

I will be grateful for your comments.

One of the most popular logistics concepts in the world, on the basis of which a large number of micrologistics systems have been developed and operate, is concept of “requirements/resource planning”(requirements/resource planning , RP). The RP concept is often contrasted with the just-in-time logistics concept, meaning that push-type logistics systems are based on it (unlike the JIT approach).

Push (pull) system is a production organization system in which parts, components and semi-finished products are supplied from the previous technological operation to the next one in accordance with a pre-formed rigid production schedule.

Material resources and semi-finished products are “pushed” from one link of the production logistics system to another. In a similar way, finished products are “pushed” into the distribution network. A common disadvantage of the push system is insufficient tracking of demand with the mandatory creation of safety stocks. It is the presence of safety stocks that allows us to take into account changes in demand and prevent production disruptions. As a result of storing inventory, turnover slows down working capital enterprises, which increases the cost of production of finished products. Proponents of this concept, comparing it with the Just-in-Time concept, note the greater stability of the “push” system in the face of sharp fluctuations in demand and unreliability of resource suppliers.

Based on the established production schedule, MRP I systems implement a time-phase approach to establishing the value and regulating the level of inventory. Since this, in turn, generates the volume of required material resources for the production or assembly of a given volume of finished products, MRP I is a typical “push” type system, an enlarged diagram of which is shown in Fig. 4.

Basic micrologistics systems based on the concept of “requirements/resource planning” in production and supply are systems of “materials/manufacturing requirements/resource planning, MRP I / MRP II”, and in distribution (distribution) - systems, “product/resource distribution planning” (distribution requirements/ resource planning, DRP I / DRP II).

Material flow

Order

Fulfillment of an order

Fig.4. MRP I as a “push” type system;

MR - material resources; WP - work in progress; GP - finished products

The MRP I system was developed in the USA in the mid-1950s, but became widespread in both the USA and Europe only in the 1970s, which was associated, as already noted, with the development of computer technology. Micrologistics systems similar to MRP I were developed around the same time period in the USSR and were initially widely used in the military-industrial complex. The usual practice of using MRP I systems in business is associated with planning and monitoring procedures for ordering and supplying (purchasing) material resources, as a rule, a wide range for industrial enterprises manufacturing engineering products. The problems that arise during the implementation of the MRP I system relate to the development of information, software and mathematical support for calculations and the selection of a set of computer and office equipment, i.e. to those problems that are typical for automated control systems for production and technological processes. The purpose of implementing MRP I is to increase the efficiency and quality of planning resource requirements, reduce the level of inventories of material resources and finished products, improve procedures for controlling inventory levels and reduce costs associated with these logistics functions.

Practical applications typical of MRP I systems are in the organization of production processes along with the procurement of material resources. According to the definition of the American researcher J. Orlisky, one of the main developers of the MRP I system, the “materials requirements planning (MRP system) system in the narrow sense consists of a number of logically related procedures, decisive rules and requirements that translate the production schedule into a “chain of requirements” which are synchronized in time, as well as the planned coverage of these requirements for each unit of inventory of components required to meet the schedule. The MRP system reschedules the sequence of requirements and coverages as a result of changes in either the production schedule, inventory structure, or product characteristics.”

MRP systems deal with materials, components, semi-finished products and their parts, the demand for which depends on the demand for specific finished products. Although the logistics concept itself, which is the basis of the MRPI system , was formed quite a long time ago (since the mid-1950s), but only with the advent of high-speed computers was it possible to put it into practice. At the same time, a revolution in microprocessor and information technology has stimulated the explosive growth of various MRP system applications in business. The main objectives of MRP systems are:

Improving the efficiency of quality planning of resource requirements;

Planning the production process, delivery schedule, procurement;

Reducing the level of inventories of material resources, work in progress and finished products;

Improving control over inventory levels;

Reducing logistics costs;

Satisfying the need for materials, components and products.

MRP I made it possible to coordinate plans and actions of units logistics system in supply, production and distribution throughout the enterprise, taking into account constant changes in real time (“on line”). It is now possible to coordinate medium- and long-term supply, production and sales plans in MRP, as well as carry out ongoing regulation and control of the use of inventories.

In the process of achieving these goals, the MRP system ensures the flow of planned quantities of material resources and product inventories over the planning horizon. System

Rice. 5. Block diagram of MRP I system

It includes the following information:

1. Consumer orders, forecast of demand for finished products, production schedule - MRP input I.

2. Database of material resources - nomenclature and parameters of raw materials, semi-finished products, etc.; norms of consumption of material resources per unit of output; timing of their delivery for production operations.

3. Inventory database - the volume of production, insurance and other stocks of material resources in warehouses; compliance of cash reserves with the required quantity; suppliers; supply parameters.

4.Software package MRP I - the required total volume of initial material resources depending on demand; chain of requirements (needs) for material resources, taking into account inventory levels; orders for volumes of input material resources for production.

5. Output machinegrams - a set of output documents: an order for material resources from suppliers, adjustments to the production schedule, delivery schemes for material resources, the state of the MRP I system, etc.

The input of the MRP I system is consumer orders, supported by forecasts of demand for the company's finished products, which are included in the production schedule (finished product release schedules). Thus, as with just-in-time micrologistics systems, customer demand is the key factor in MRP I.

Information Support MRP I includes the following data:

Production plan for a specified item for a specific date;

Data on materials containing specific names of the required parts, raw materials, assembly units, indicating their quantity per unit of finished product;

Data on stocks of material resources necessary for production, lead times of orders, etc.

The database on material resources contains all the required information about the nomenclature and main parameters (characteristics) of raw materials, materials, components, semi-finished products, etc., necessary for the production (assembly) of finished products or their parts. In addition, it contains standards for the consumption of material resources per unit of output, as well as files of the times of delivery of the corresponding material resources to the production divisions of the company. The database also identifies connections between individual inputs production units in terms of consumed material resources and in relation to final products. The inventory database informs the system and management personnel about the presence and size of production, insurance and other required stocks of material resources in the company's warehouse, as well as their proximity to a critical level and the need for their replenishment. In addition, this database contains information about suppliers and parameters for the supply of material resources.

The MRP I software package is based on systematized production schedules (schedules for the release of final products) depending on consumer demand and comprehensive information obtained from databases on material resources and their stocks. Algorithms embedded in software modules systems initially translate the demand for finished products into the required total volume of initial material resources. The programs then calculate a chain of requirements for input material resources, semi-finished products, and work-in-process volumes based on information about the appropriate inventory level, and place orders for volumes of input material resources for production (assembly) areas of finished products. Orders depend on the specified nomenclature, volume of requirements for material resources and the time of their delivery to the appropriate workplaces and warehouses.

After completing all the necessary calculations, the output complex of machine diagrams of the MRPI system is generated in the company’s information and computer center , which is transferred in documentary form to production and logistics managers for making decisions on organizing the provision of production sites and warehouse facilities of the company with the necessary material resources. A typical set of output documents from an MRP I system contains:

Requirements for material resources ordered from suppliers specified in terms of nomenclature, volume and time;

Changes that need to be made to the production schedule;

Schemes for the delivery of material resources, volume of supplies, etc.;

Canceled requirements for finished products, material resources;

MRP system status.

However, the preparation of primary data requires significant costs and accuracy. MRP I is usually used in planning procedures for ordering and supplying a large range of materials, for example, for mechanical engineering enterprises. The following disadvantages of micrologistics systems based on the MRP approach can be identified:

A significant amount of calculations, preparation and pre-processing of a large amount of initial information, which increases the duration of the production period and logistics cycle;

An increase in logistics costs for order processing and transportation as the company strives to reduce inventory levels or switch to producing finished products in small volumes with high frequency;

Insensitivity to short-term changes in demand, since they are based on control and replenishment of inventory levels at fixed order points;

A significant number of failures in the system due to its large size and overload.

These disadvantages are superimposed on the general disadvantage inherent in all “push” type micrologistics systems, which include MRP1 systems , namely: insufficiently strict monitoring of demand with the mandatory presence of safety stocks.

MRP I systems are primarily used when the demand for input materials is highly dependent on customer demand for final products. The MRP I system can work with a wide range of material resources (multi-assortment initial material flows). Although proponents of the just-in-time concept argue, and not without reason, that “pull” micrologistics systems based on the principles of this concept respond faster and more efficiently to changes in consumer demand, there are cases when MRP I systems are more effective. This is true for firms that have fairly long production cycles under conditions of uncertain demand. At the same time, the use of MRP I systems allows firms to achieve the same goals as when using JIT technology, in particular, to achieve a reduction in the duration of the full logistics cycle and the elimination of excess inventories, if the time for making decisions on managing production operations and purchasing material resources is comparable to frequency of demand changes.

Logistics is one of the most complex, responsible and “multi-tasking” areas of an enterprise’s work. To tie together disparate processes in warehouses, take into account the structure of inventories, the peculiarities of transportation of materials and finished products, facilitate the work of personnel and increase its efficiency, special systems - MRP - were developed. The abbreviation stands for “materials requirements planning”, such software is based on the Kanban concept, JIT methodologies (“Do it on time”) and designed to solve problems:

• regulation of the supply of components for the needs of the production process;
• work with a wide range of materials or goods;
• continuity of operation of the enterprise (without downtime) without accumulating excess stocks and bringing them to the minimum required level, unloading the warehouse;
• daily planning of the material needs of the enterprise;
• organizing and “linking” delivery/dispatch schedules, purchasing, production operations, and so on.

MRP systems are among the most popular shells and logistics concepts in the world. Today, second-generation software and ERP modules are actively developing; they reduce enterprise costs as a whole and with their help you can organize a simple, transparent, well-functioning workflow.

Features and Benefits of MRP

There are many products on the domestic market that operate on the basis of the MRP concept. ASAP Consulting company offers effective tools to create a qualitatively new and efficient environment for planning material requirements and logistics work in general. Using our products you can quickly and easily:

• determine how much and when finished products need to be produced;
• generate data on required quantity material resources and transfer them to the relevant departments;
• draw up clearly interconnected production and warehouse schedules;
• calculate the net need for components and raw materials at each point in time;
• optimize the amount of inventory - reduce it without the risk of shortage;
• amend plans, monitor the work of departments, and so on.

The MRP system includes information from the inventory book (including work in progress, finished goods and semi-finished products), orders planned and awaiting shipment, and specifications of product compositions. Then the algorithms process them. “At the exit”, the customer of the package receives generated order plans with changes, reports on their execution - they determine the strategy for using materials within the enterprise and further external purchases. You can also use the information for further precise planning. The system determines optimal production schedules, serves as a convenient tool for reducing internal production costs and identifies bottlenecks in the company’s work.

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