Comparison of JIT, MRP, and Synchronized Manufacturing

JIT production focuses on sourcing raw materials just in time for factory use according to a production schedule; it helps manufacturers store low quantities of raw materials. The alignment of the raw materials to the production schedule is done (it doesn't work well when the materials are delayed). Synchronous manufacturing ensures that a manufacturer processes raw materials into finished products to place orders or first-in/first-out. Raw materials are turned into finished products that the customers place orders (can work if the materials are delayed). MRP involves inventory management which easily estimates the raw materials.

It might be used: For example, for a car builder to build its final product, they need their parts from the suppliers. To build the specific car on the said date, the parts shall be received in time just as they needed them to be. The delivery quantity is equal to the quantity that needs to be produced.

Amounts of Raw Materials and WIP inventories: The raw materials for sub-assembly must be completed before production.

Where it might be used: For example, the production schedules an item to buffer the finished goods (excess but not so much), then they plan to buffer the next day since the item will be delivered. But the sub-parts needed haven't had a production order yet. The MRP can help the planner advance the raw materials to produce the finished product to avoid delays.

Amounts of Raw Materials and WIP inventories: replenishing raw materials before the inventory hits.

Question

JIT

MRP

Synchronized Manufacturing

Where used

Continuous flow, make-to-stock

Job shop, custom shop

Job shop, custom shop

WIP

Very low

Very high

Low

Production cycle time

Very short

Very long

Short

Schedule flexibility

Level production for a minimum of 30 days

MRO frozen for 30 days, but variable in work centers

Can be changed daily as needed

Regard to capacity limits

High, Tries to balance capacity

Terrible. May start okay but quickly becomes inaccurate

Is founded on capacity limitations

Labor skills

Multi-skilled to help out other areas

Specialized in own work area

Same as MRP

References

Albino, V., & Okogbaa, O. G. (2019). Synchronization of Production Rate with Demand Rate in Manufacturing Systems. InOptimization Methods for Manufacturing(pp. 1-1). CRC Press.