JAWAHARLAL NEHRU TECHNOLOGICAL UNIVERSITY HYDERABAD B.Tech III PRODUCTION PLANNING AND CONTROL Previous Question Paper (August - 2022 - R18)

Production Planning and Control (PPC) is the management function that directs and coordinates the flow of materials and services through the production process. It involves the systematic planning of production activities to ensure that goods are produced at the right time, in the right quantity, and at the lowest possible cost, followed by the control mechanism to ensure that the actual production conforms to the planned schedule.

Objectives of PPC:

• Optimum Utilization of Resources: Ensuring maximum efficiency of men, machines, and materials.
• Inventory Management: Maintaining an ideal level of inventory to avoid stockouts while minimizing carrying costs.
• Cost Reduction: Minimizing production costs through better resource allocation and waste reduction.
• Customer Satisfaction: Ensuring timely delivery of products to meet market demand.
• Smooth Workflow: Eliminating bottlenecks and ensuring a continuous flow of production.

Types of Production Systems:

• Job Shop Production: Characterized by the manufacturing of one or a few units designed and fabricated as per customer specifications. It requires highly skilled labor and general-purpose machines.
• Batch Production: Involves the production of items in lots or batches. It is a middle ground between job shop and mass production, where similar products are produced periodically.
• Mass Production: Involves the continuous production of standardized products on a large scale. It utilizes special-purpose machines and assembly lines to achieve high volume and low unit cost.
• Continuous Production: A system where the production facility is arranged as per the sequence of operations. It is used for products like chemicals, oil refining, and power generation where the process cannot be interrupted.

Material Requirements Planning (MRP) and Just-in-Time (JIT) are two distinct philosophies in inventory and production management:

• MRP (Material Requirements Planning): This is a push-based system driven by a Master Production Schedule (MPS). It calculates the exact quantity and timing of raw materials and components needed to meet production targets. It is highly effective in complex manufacturing environments with long lead times and dependent demand items. It relies heavily on accurate bills of materials and inventory records.
• JIT (Just-in-Time): This is a pull-based system where production is triggered only by actual customer demand. The goal is to eliminate waste (Muda) by maintaining zero or near-zero inventory. JIT emphasizes small lot sizes, frequent deliveries, and high quality (Total Quality Management). It requires strong supplier relationships and a highly reliable production process to function without buffer stocks.

In evaluation, MRP provides better planning and visibility for long-term scheduling and complex assemblies, whereas JIT excels in reducing carrying costs and improving operational agility in stable, repetitive manufacturing environments.