Demand for raw materials, components, parts depends on the schedule of the assembly line , which is produced finished products . For example, for everyone must collect the car windshield, a steering wheel, four tires, plus one spare. Similarly, many of the goods for
service and maintenance depend on the performance graph works. At the heart of
the reception, which is called planning resource requirements (MRP), is an
understanding based on demand.
MRP- systems are designed to support the activities in the production, maintenance works or application due to meet the demands laid down in the main chart production activities. To determine these requests, MRP- systems require precise specification of materials for each finished project or product. These specifications are subject to a variety of forms, but at the conceptual level, it is advisable to consider them as structural trees.
Not all the organizations have been successful in trying to implement MRP - system. Their implementation may take years and large investments in staff training and data, organizational adjustments, and the acquisition of computer hardware and software. However , most organizations that have successfully implemented similar systems have been less inventory levels , faster execution of orders with more precise fulfillment of the conditions of supply and more rigorous discipline that ensures MRP makes investment in these systems are well-founded. In addition, MRP- system allows you to quickly carry out the re- scheduling and re- drafting work schedules in dynamic changes in the environment.
Initial elements of MRP.
We can identify three main categories of source elements MRP. The whole system is based on forecasts of requirements as they relate to a specific time period (the main production schedule), where at a detailed level is defined as the final products should be produced during this time. The second component of the original is a structured material specification.
In the structured specification uses the information obtained on the basis of technological and / or process records, which allows for a detailed level to install the components required for the production of the finished product. The third component - an inventory list, which contains information, in particular on open orders, lead times, techniques used to determine the size of the party, quantitative and temporal parameters of the order.
Logic MRP allows to simultaneously determine how much product to order it, and when. This calculation is based on the assumption that all the information is accurate and that certain materials will be ordered as needed. MRP- systems can help to produce work in accordance with the established timetable, prevent downtime, correct sizing of orders and identify situations because of which the detainees have orders to deliver freight forwarding service.
Planning for Batches
The rules for determining the size of the party should be specified for each product to a plan of MRP. By the choice of rules that determines the size of the party, should be approached rightly, as it affects the cost of maintaining inventory and operating costs, in particular, the costs of setting up.
There are four basic rules for determining the size of the order: party supplies, corresponding to the requirements (lot-for-lot, L4L); economically Ordered Quantity (EOQ); party with least total cost (LTS); party with minimal cost per one unit (least unit cost, LUC).
Most often, party supply matches demand. In this case, the calculation does not take into account the costs of setting up, the maintenance of inventory or power limitations. Lot size is determined based on the final determination of the amount for each period.
Admission on the basis of determining the economically justified lot size is used , taking into account the cost of maintaining a balance of stocks and ( or) the cost of placing an order . It uses a formula EOQ for determining the size of orders, which requires estimates of annual demand, the cost of maintaining inventory and setup costs ( to place an order ) .
In the method of the party with the minimum total cost compared to the cost of the party in different sizes and choose the size of the order, in which the total cost is minimal. This method refers to the dynamic methods.
Another dynamic method is the determination of the party at the lowest cost per one unit of the party. It takes into account the cost of maintaining inventory and set-up (by placing an order) per unit of output.
In applying MRP it is difficult to determine the size. Since most of the techniques for determining the party requires information on costs and annual demand, the effectiveness of decision-making depends on the accuracy of the data used.
Modern MRP- systems
With the development of information technology systems, MRP- system have been significantly modified and is now much better to help plan and coordinate the production and delivery. One of the most significant additions to the MRP- system has capacity requirements planning (CRP). CRP implements the same function for the production of resources, and MRP for materials. If the MRP- system is designed to plan the materials, then it is based on CRP to calculate the required manpower and necessary equipment by working shifts and time periods. After that the required resources can be compared with the resources available. If the power is not enough, the manager must either correct it or change the primary production schedule. Such a feedback loop with the main production schedule allows you to get MRP’s loop (closed-loop MRP), describing the dynamics of development.
CRP- model is often associated with the module that controls the production plan for the shop floor level. The purpose is to measure the output and compare it with the set -up. This information allows you to identify difficult areas and is necessary for the permanent capacity planning.
Manufacturing resource planning (MRPII) is an associated planning process in the company with the financial system. Systems MRP II unify verifiability production scenarios at the «what if" with the predictions of financial performance and cash flows, so you can set more reasonable goals of the company in terms of sales and profitability.
Many companies use enterprise resource planning (ERP), which are included in the MRP’s that enables the integration of business systems and processes. ERP-system - is software that allows all areas of the company (production, finance, sales, marketing, human resources and supply) to integrate and analyze information. ERP might be a link between the communications of orders from customers to fulfill these processes. Therefore fully implemented ERP-system helps separate deliveries to know about the orders received by the sales department, production department - on the status of the supply of raw materials, the sales department - the lead time for products and services, as well as their availability, and the finance department - on financial transactions and liabilities.
Thus, contemporary MRP system - it's not just a device for calculating the amount of necessary materials and time when they are needed. This is the information and communication system, covering all areas of the organization. It helps managers to measure the performance of operation, plan sending orders ( purchase , internal orders ) and to model the main production schedule to reflect changes workloads ( for example, because the proceeds of a new order , the delay of materials , machine breakdowns or illness the worker) . Integration requires these systems, makes an organization to have more accurate information, abandon the approximate rules and use the same data in all divisions. As a result of reduced inventory levels, improved service levels, easier access to information and the information itself is becoming better and, most importantly, increases the speed of planning in the event of problems that have not been taken into account.
