backward and forward scheduling

[Former Member]

Hi gurus,

for backward scheduling, how does system determine those dates (such as material availability date), is there any customizing for the time for transit/loading/picking/packing/transport planning?

for forward scheduling, how does system determine the start of scheduling, ie material availability date?

thanks very much!

[Lakshmipathi · Accepted solution]

Dear bo zhang

In backward scheduling, the system first calculates backwards from the order finish date through the float after production to the production finish date. After this the individual operation dates are calculated backwards, starting from the last operation finish date. The first operation start date gives the start of production.

In forward scheduling the system starts from the current date and calculates through the float before production into the future. Then the individual operation dates are calculated starting from the first operation finish date and working forwards into the future.

You can specify whether lead time scheduling is to be carried out forwards or backwards in the parameters for detailed scheduling in Customizing for capacity planning or in Customizing for MRP.

In lead time scheduling there are three scheduling levels available for capacity planning:

• Detailed scheduling

• Production-rate scheduling

• Rough-cut scheduling

With detailed scheduling you usually use the routing to carry out scheduling and capacity requirements planning for a BOM level. The lead time is divided up into the operation segments: setup, processing and teardown.

Production-rate scheduling is implemented in repetitive manufacturing. Production-rate scheduling is based on the times for the rate routing and is also carried out for a BOM level.

Rough-cut scheduling is based on the scheduling data in the rough-cut planning profiles and at a higher planning level (SOP) provides an initial overview of the capacity situation. The rough-cut planning profile represents a cumulation of the overall BOM structure.

thanks

G. Lakshmipathi

[Former Member · Accepted solution]

thanks Jude and Lakshmipathi

Hi Jude, will you please show me the Tcode for customizing picking/packing/loading/transit time. I can't find them anywher. thanks very much

Hi Lakshmipathi, thanks very much. however, concept and principle used in your answer seems not be used in SD function. so where does it used for?

many thanks

Bo Zhang

[Former Member]

The system fist does a backward scheduling to determine whether the scheduled delivery date can be met at the time of the sales order at the time of order confirmation. This is based on the following criteria:

MAterial Availability date, Transport planning date ( Pick/Pack time), Transport lead time, Loading date ( Loading time), Goods Issue date ( Transit time ), Required delievery date. When you do a backawrd schedule the Order date should be earlier than the material availability date otherwise the system does a forward scheduling taking the new material availability date and then calculates the new delivery date based on the above parameters and proposes the same.

The pick/ pack, loading times are dealt in the customising for shipping point, The transit time for shipping is done in the transportation.

Regds

Jude