Distribution of planned independent requirements can be key in getting your MRP results exactly right. This post is about how to break down your Sales and Operations Plan and schedule it for MRP. E.g. Assume your SOP is planned in monthly buckets, but you plan your production in weekly buckets and you use forward scheduling for your production orders. In this case you want independent requirement quantities show on the first day of the week. Another example: since you plan production on a daily basis you want your monthly forecast spread out on a daily basis throughout the month. Distribution of planned independent requirements can help you achieve this.
First you define the distribution function itself.
Production > Production Planning > Demand Management > Planned Independent Requirements > Automatic Split > Distribution Function for Automatic Split > Define Distribution Function
Here you specify the percentage of the quantity that needs to be available or released after a certain percentage of time. You can e.g. determine that total quantity should be available at the beginning, at the end or spread over 5 time points (like work days). To reach the goal of the first example you determine that after 0% of time has passed, 100% of quantity should be available (see below function S10).
Next step is to define the distribution strategy.
Production > Production Planning > Demand Management > Planned Idnependent Requirements > Automatic Split > Distribution Function for Automatic Split > Define Distribution Strategy
This let’s you determine either of two things:
1. spread the quantities exactly over the points in time defined in the previous step, or;
2. smooth the quantities along the time axis according to your function.
Imagine 2 time points in a month (20 working days) where 80% is available after 20% of production time and 100% after 100%. Using the second strategy you can spread the 80% over the first 4 days of production. Using the first strategy the total 80% will become available only after four days. To achieve this you also need to determine the period split for the strategy.
Production > Production Planning > Demand Management > Planned Independent Requirements > Automatic Split > Define period split for automatic split
Here you define how many of the first few weeks need to be split into daily quantities and/or how many of the first few months need to be split into weekly quantities. You then decide how you are going to spread your quantities. You decide whether your distribution strategy applies to the weeks and/or to the months by assigning the strategy two the last two columns.
The only thing that is required as a last step is to assign the period split to an MRP group or independent requirement version. When you opt for the last the periods will be split at the time of copying the demand plan from SOP or Flexible Planning to the Demand Management tables (MD61).
You may need to try different settings in order to achieve what you need, especially if your require more complex distributions.