1. Using Order Promising
  2. Consider Your Lead Times

Consider Your Lead Times

Consider how your lead times affect promising.

The Create Bills of Resources scheduled process populates the Lead Time Offset attribute for each item.

If you set the sourcing rule for your item to Make At, then the Lead Time Offset will include the time it takes to process and post process the item. If you specify that the item is critical, and if the item resides in more than one level below the manufactured item, then your lead time offset will account for the lead times of the intermediate items, even if they aren't critical.

Assume your lead times will include Taiwan, Los Angeles, and Denver.

  1. Taiwan transfers the critical CM153 chip to Los Angeles.
  2. Los Angeles uses the CM153 that it gets from Taiwan to assemble the noncritical AS301 motherboard.
  3. Los Angeles assembles the AS301 motherboard into the AS54888 computer, which is the final assembled item.

The lead time will include:

  • Processing lead time and postprocessing lead time that Taiwan needs to make the CM153 chip, plus:
  • Transfer lead time to get the CM153 chip from Taiwan to Los Angeles according to the default shipping method that you set up between Taiwan and Los Angeles, plus:
  • Processing and postprocessing lead time that Los Angeles needs to install the CM153 chip onto the AS301 motherboard, plus:
  • Processing and postprocessing lead time that Los Angeles needs to install the AS301 motherboard into the AS54888 computer, plus:
  • Transfer lead time to get the AS54888 from Los Angeles to Denver.

In summary, the lead time is different depending on what you're doing.

What You're Doing How Long it Takes
Assemble an item in the same organization where you make it
  1. The parent item’s processing lead time
  2. Plus the parent item’s postprocessing lead time
Assemble the item and its subassemblies at the same organization
  1. The processing lead time
  2. Plus the postprocessing lead time
Transfer an item from an upstream organization to a downstream organization
  1. The destination's postprocessing lead time plus its transit lead time
  2. Plus the parent item’s processing lead time plus its postprocessing lead time.
Transfer the assembly and subassemblies from an upstream organization to a downstream organization
  1. The destination's postprocessing lead time plus its transit lead time
  2. Plus the item’s processing lead time plus its postprocessing lead time.

Detailed Lead Time Example

Consider this flow.

Consider this flow.

Note

  • The assembled AS301 item is critical in the Denver Distribution Center.
  • Subassembly SB111 in the Los Angeles Factory isn't critical.
  • The CM202 item in the Seattle Factory is critical, and it is two levels below the AS301.
  • The CM153 item in Los Angeles is critical, and it is one level below the AS301.
  • You have done all the required Promising setups, such as sourcing rules, assignment sets, ATP rules, and so on.

Here are your transit times between facilities.

From To Transit Time
Los Angeles Denver 2
Seattle Los Angeles 3

Here are your lead times.

Item Organization Critical Processing Lead Time Postprocessing Lead Time
AS301 Denver Yes 2 days 4 days
AS301 Los Angeles No 2 days 3 days
SB111 Los Angeles No 1 day 1 day
SB111 Seattle No 1 day 1 day

Here are the lead times that the scheduled process creates in your bill of resources.

Assembly Assembly Organization Component Component Organization Lead Time
AS301 Denver CM202 Seattle 17 days
AS301 Denver CM153 Los Angeles 11 days

Here's the calculation for the CM202's 17 day lead time.

Lead Time Calculation for the CM202 Running Total
1 day processing plus 1 day postprocessing for the SB111 in Seattle equals 2 days 2

3 days transit time to get from Seattle to Los Angeles

 2 + 3 = 5
1 day postprocessing for the SB111 in Los Angeles 5 + 1 = 6
2 days processing plus 3 days postprocessing for the AS301 in Los Angeles equals 5 more days 6 + 5 = 11
2 day transit time to get from Los Angeles to Denver 11 + 2 = 13
4 days postprocessing for the AS301 in Denver 13 + 4 = 17

Here's the calculation for the CM153's 11 day lead time.

Lead Time Calculation for the CM153 Running Total
2 days processing plus 3 days postprocessing for the AS301 5
2 days transit time to get from Los Angeles to Denver 5 + 2 = 7
4 days postprocessing for the AS301 7 + 4 = 11

Related Topics