Production planning is about strategy, and production scheduling is about rules. In addition to this, the production plan is principled:
1. Goals. The primary goal of production planning and control is delivery. Delivery is not only the primary goal of the production system, but also the primary goal of the production plan. Leaving delivery to make plans is all hooliganism.
2. Stratification. Due to the limitation of lead time, different lead times need to be covered by different levels of production planning. Normally, we divide production planning into two levels: balanced planning, strategy-oriented "resource planning", annual "comprehensive planning", and quarter-oriented "production and marketing planning". Delivery Planning, Master Requirements Planning, Master Production Planning, Material Requirements Planning, SFP, and many more.
3. Segmentation. Delivery planning is a process that involves at least four stages: Master Demand Planning, Master Production Planning, Material Requirements Planning, and SFP. The previous paragraph is the input of the next paragraph, which is the front and back paragraphs of the logic.
4. Integration. At the very least, the four segments of the delivery plan need to be integrated, which is the transfer relationship of data, and it is best to ensure that the data does not land.
5. Scrolling. Plans need to be rolled to accommodate changes. Scroll by different cycles. Delivery schedules, normally, are per day. Of course, slow logistics can be weeks. Fast logistics, can be half a day. In the balanced plan, the resource plan is yearly, the comprehensive plan is best monthly, and the production and sales balance is best biweekly.
6. Long cycle.
Balance planning is naturally long-term, while delivery planning needs to cover the demand cycle and the procurement cycle, which is the longer of both. Only with long-term coverage, the balance of supply, production and marketing can be achieved
In addition to the principles that production planning needs to follow, generally speaking, production planning focuses on strategy, as opposed to the type of production
Discrete, the planning strategy is tracked, output = demand.
Process-based, the planning strategy is balanced, output = capacity.
Semi-process, the planning strategy is hybrid, output = capacity = demand.
Production scheduling is generally about rules:
Reverse the row, give priority to urgency, and gradually chase forward.
Arrange in order, set up in line, and gradually push back.
Bottleneck row, the bottleneck is to pull the production of the previous process with the buffer consumption before the bottleneck. After the bottleneck, the bottleneck output is gradually pushed (first-in, first-out).
In real scenarios, it is often "inverted and orderly", that is, "inverted" is an emergency priority;Priority is given to urgent tasks. "Shuntou" is a complete set of online and allows the task to start in advance (relying on the current daily schedule).