Materialbedarfsplanung

What Is Materialbedarfsplanung?

Materialbedarfsplanung (MRP), or Material Requirements Planning, is a production planning, scheduling, and inventory control system used to manage manufacturing processes. It is a fundamental component of effective Supply Chain Management for businesses that produce goods. The primary objective of Materialbedarfsplanung is to ensure that materials and components are available when needed for production and that finished goods are ready for delivery to customers. By aligning material availability with production schedules, Materialbedarfsplanung helps companies optimize their production schedules, minimize Inventory Management costs, and enhance overall operational efficiency. It plays a critical role in balancing the intricate needs of Manufacturing with the goal of achieving Cost Efficiency.

History and Origin

The concept of Materialbedarfsplanung emerged in the 1960s, driven by the increasing complexity of manufacturing processes and the advent of computer technology. Before MRP, businesses often relied on simpler reorder point methods like Economic Order Quantity to manage inventory, which could lead to excessive stock or shortages. Joseph Orlicky is widely credited with developing the first formal Material Requirements Planning system in 1964 at Black & Decker, utilizing an IBM 1401 computer. This marked a significant shift from manual inventory processes, aiming to ensure materials were available for production, maintain low inventory levels, and plan manufacturing activities and purchasing schedules¹¹, ¹². The widespread adoption of MRP systems gained momentum in the 1970s, as companies recognized their potential for significant cost savings and efficiency improvements¹⁰.

Key Takeaways

• Materialbedarfsplanung (MRP) is a system for planning and controlling materials and components required in manufacturing.
• Its core purpose is to ensure timely availability of materials, maintain minimal inventory, and streamline production and purchasing activities.
• MRP operates by translating a Master Production Schedule into specific requirements for raw materials and sub-assemblies.
• Successful implementation relies heavily on accurate data, including Bill of Materials, inventory records, and Lead Time information.
• It contributes to increased production efficiency, reduced inventory costs, and improved customer service by preventing stockouts and delays.

Formula and Calculation

While Materialbedarfsplanung isn't a single formula like a financial ratio, its operation involves a logical calculation based on several key inputs to determine net material requirements. The fundamental calculation for each component at each level of the Bill of Materials can be conceptualized as:

Where:

• (\text{Gross Requirements}) refer to the total quantity of a component needed to produce the planned output of higher-level assemblies, derived from the Master Production Schedule.
• (\text{On-Hand Inventory}) is the current physical stock of the component.
• (\text{Scheduled Receipts}) are the quantities of the component that are already ordered and expected to arrive by a specific date.

Once net requirements are determined, the system calculates planned order releases by considering lead times, ensuring orders are placed sufficiently in advance to meet production needs.

Interpreting the Materialbedarfsplanung

Materialbedarfsplanung systems provide a detailed plan that shows when materials need to be ordered and when production steps need to be initiated. Interpreting the output of a Materialbedarfsplanung system involves understanding the planned order releases, which indicate the quantity and timing of purchase or production orders for each component. A well-executed Materialbedarfsplanung system helps minimize the amount of Work-in-Process inventory and ensures that there are enough components to meet the production schedule without excessive stockpiling. This interpretation allows managers to anticipate potential shortages or surpluses, enabling proactive adjustments in Production Planning or procurement.

Hypothetical Example

Consider a bicycle manufacturer, "CycleWorks," that needs to produce 100 finished bicycles next month. Each bicycle requires:

• 1 Frame
• 2 Wheels (assembled)
• 1 Handlebar Assembly

A single "Wheel Assembly" requires:

• 1 Wheel Rim
• 1 Set of Spokes
• 1 Tire

CycleWorks' Materialbedarfsplanung system would start with the demand for 100 finished bicycles (the gross requirement).

1. Frames: If CycleWorks has 20 frames currently in stock and 10 frames are scheduled to arrive next week, the net requirement for frames would be (100 - (20 + 10) = 70) frames.
2. Wheel Assemblies: For 100 bicycles, 200 wheel assemblies are needed. If CycleWorks has 50 assembled wheels in stock and 20 are scheduled to arrive, the net requirement is (200 - (50 + 20) = 130) wheel assemblies.
3. Handlebar Assemblies: Similarly, if 100 handlebar assemblies are needed, and 30 are on hand with 0 scheduled receipts, the net requirement is (100 - (30 + 0) = 70) handlebar assemblies.

The system then "explodes" the requirements for wheel assemblies down to their components. For 130 net wheel assemblies, CycleWorks needs 130 wheel rims, 130 sets of spokes, and 130 tires. The Materialbedarfsplanung system would then check the on-hand inventory and scheduled receipts for these individual components to calculate their net requirements and generate planned purchase orders, taking into account each component's Lead Time. This detailed breakdown ensures that all necessary raw materials are available precisely when needed, preventing production delays and optimizing inventory levels.

Practical Applications

Materialbedarfsplanung finds its primary application in the Manufacturing sector, particularly in environments where products have multiple components and layers, such as automotive, electronics, and discrete assembly industries. It is critical for managing Logistics and ensuring the smooth flow of goods through the production process. Companies use Materialbedarfsplanung to:

• Optimize Inventory: By calculating exact material needs based on Demand Forecasting, MRP helps reduce excess inventory and the associated holding costs, while also preventing stockouts.
• Improve Production Scheduling: It enables precise [Production Planning] (https://diversification.com/term/production-planning) by detailing when each component is needed, allowing for better allocation of resources and prevention of bottlenecks.
• Enhance Supplier Coordination: MRP outputs facilitate better communication with suppliers by providing clear, timed purchasing requirements, which can lead to stronger supply chain relationships.
• Increase Responsiveness: With a clear picture of material availability, businesses can respond more effectively to changes in demand or supply.

Even with the rise of more advanced systems, the fundamental logic of Materialbedarfsplanung remains relevant for many manufacturers, playing an important role in managing [Finished Goods] (https://diversification.com/term/finished-goods) and components. For instance, the system's logic can still be used by manufacturers to provide daily forecasts to their suppliers, even in the context of "pull" manufacturing systems⁹. The Federal Reserve System also monitors global supply chain pressures, which directly impact the need for robust planning systems like MRP in manufacturing to mitigate disruptions⁷, ⁸.

Limitations and Criticisms

Despite its benefits, Materialbedarfsplanung systems come with certain limitations and criticisms. One significant challenge is the reliance on accurate input data. Inaccurate or outdated data regarding [Inventory Management] (https://diversification.com/term/inventory-management) levels, [Lead Time] (https://diversification.com/term/lead-time), or [Bill of Materials] (https://diversification.com/term/bill-of-materials) can lead to faulty outputs, resulting in incorrect material requirements, production delays, or excessive stock⁵, ⁶. This highlights that "garbage in, garbage out" is a major pitfall.

Another criticism is that traditional MRP systems are often based on a "push" system of manufacturing, where production is initiated based on a forecast rather than actual customer demand. This can be less flexible than "pull" systems like Just-in-Time manufacturing, which only produce items as they are needed⁴. Furthermore, traditional MRP may not adequately account for capacity constraints, leading to unrealistic production schedules if not integrated with a broader Resource Planning system³. Implementation in smaller businesses can also face challenges due to limited resources, lack of in-house expertise, and resistance to change². The complexity of procedures required for optimal schedules can make MRP systems challenging for operating personnel to understand¹.

Materialbedarfsplanung vs. Manufacturing Resource Planning (MRP II)

Materialbedarfsplanung (MRP) and Manufacturing Resource Planning (MRP II) are closely related but represent different stages in the evolution of production planning systems.

While Materialbedarfsplanung is concerned primarily with ensuring the availability of materials for Manufacturing, Manufacturing Resource Planning (MRP II) expands this scope to include the planning of all resources required for manufacturing, such as labor, machinery, and finances. MRP II systems are often described as "closed-loop" systems because they provide feedback on how actual production compares to the plan, allowing for adjustments to the Master Production Schedule and capacity plans. This broader integration makes MRP II a more comprehensive business management tool.

FAQs

What type of businesses benefit most from Materialbedarfsplanung?

Businesses involved in discrete Manufacturing, where products are assembled from multiple components (e.g., electronics, automotive, furniture), benefit significantly from Materialbedarfsplanung. It is especially useful for companies with complex Bill of Materials and variable demand patterns.

Can Materialbedarfsplanung be done manually?

While the core logic of Materialbedarfsplanung can theoretically be performed manually, modern MRP systems are almost exclusively software-based due to the complexity, volume of data, and speed required for accurate calculations and adjustments. Computerized systems allow for rapid processing of large datasets and dynamic updates.

How does Materialbedarfsplanung help reduce costs?

Materialbedarfsplanung helps reduce costs by optimizing Inventory Management to prevent overstocking and understocking, reducing waste from obsolete materials, minimizing production delays that lead to higher labor or expediting costs, and improving overall Production Planning efficiency.

Is Materialbedarfsplanung still relevant with newer technologies like ERP?

Yes, Materialbedarfsplanung remains highly relevant. While Enterprise Resource Planning (ERP) systems offer a broader integration of all business functions, the core material planning logic within an ERP system is often based on or includes MRP functionalities. Many ERP systems build upon the principles established by MRP and Manufacturing Resource Planning (MRP II).