Logi behind the calculation of Purchase Lead Time and Latest Order Date

  • 13 December 2023
  • 0 replies
  • 109 views

Userlevel 6
Badge +13

When the lead times are set as follow:

  1. How the “Purchase Lead Time” is calculated?
  2. How the “Latest Order Date” is calucated in Purchase Requisition Line (Distribution calendar is 5-days per week, assuming no exceptions)

Supplier Manufacturing Lead Time

External Transport Lead Time

Transport Lead Time

Internal Delivery Lead Time

Inspection Lead Time

280

0

0

4

20

 

Purchase Lead Time =  Supplier Manufacturing Lead Time  +  External Transport Lead Time   + Transport Lead Time  + Internal Delivery Lead Time  +  Inspection Lead. Time

When calcualting the Lead Time, the calendar is not relevant therefore the Purcahse Lead Time is 304 days in this scenario.

 

Then when a Purchase Requisition Line is created for this part with “Wanted Receipt Date” as 2024-10-04, the “Latest Order Date” is calculated as 2023-11-27.

The number of calendar days between 2023-11-27 and 2024-10-04 is 312 days not 304 days. There is a difference due to the used calendars.

First 280 days are calculated considering 7 working days per week. When entering the Supplier Manufacturing Lead Time per purchase part in Supplier for Purchase Part page, the number of days should be calculated considering 7 working days per week calendar as the supplier calendar is not considered for the calculation.

However the remaining Lead Times are connected to the site therefore when calculating the dates, Internal Delivery Lead Time and Inspection Lead Time, the distribution calendar for the site is cosidered (which is 5-day per week for this scenario).

As a result, 24 days for Internal Delivery Lead Time + Inspection Lead Time should be calculated as working days adding weekends. That is why actual number of days is higher than 24. In this scnario it is 32 days.

The part is manufactured by 2024-09-2 and it is transported the next 4 days. The inspection lasts for another 20 days. So the part is availabe on 2024-10-04. 4 weekends or 8 days need to be added additionaly to the calculation.

 


0 replies

Be the first to reply!

Reply