Control Key for Operations 
Use
You maintain the control key for operations in Customizing for
Shop Floor Control
, by choosing
Master Data
Routing Data
Define Control Key.
Schedule
Using the Schedule indicator you can define that an operation is scheduled. If an operation is
Scheduled , the system calculates the duration of the operation segments and the dates
Not scheduled , the system assumes that all the operation segments have a duration of 0
External Processing
If an operation is externally processed (relevant setting in the External processing key), you can define how it is scheduled. If the Sched. external op . indicator is
Not set, the system schedules the operation using the number of delivery days maintained on the external processing screen of the operation
Set, the system calculates the duration of the operation segments from the standard values
Capacity Requirements
You use the Det. Cap. Reqmnts indicator to determine whether capacity requirements are determined for an operation.