Background:  Accumulated Lead Time Calculation

Use the Accumulated Lead Time Calculation (MLT) program to calculate critical-path lead times for parent items in bills of material and print a report. See Road Map for work flow.

Note
This program does not update lead time for configured products.

This topic has these subtopics:

Types of Lead Time
Calculating Accumulated Lead Time
Accumulated Lead Time Report

Types of Lead Time

You can specify several lead times for each item in the Branch Item Maintenance (IMB) program:

Lead Time Type

Field

Definition

Manufacturing

Mfg LT

The number of days required to manufacture the item from its next level components

Order preparation

Order prep LT

The time required to prepare a manufacturing order or purchase order (for example, the time needed to get approval and process paperwork)

Delivery

Intransit LT

The number of days required after an order is placed with a vendor for the item to be delivered

Stocking

Put-away LT

The time it takes after you receive a item to put it into inventory (for example, to move it to its primary bin location)

Calculating Accumulated Lead Time

Accumulated lead time is the total the number of days required to manufacture or procure an item, including the time to purchase and manufacture all of its components on a multi-level bill of material.

The value of the LT update field (maintained in Branch Item Maintenance) determines how the item's accumulated lead time (Accumulated LT in Branch Item Maintenance) is updated:

  • E Exclude queue and move times
    Calculates the longest lead time of all components on the bill of material, ignoring the queue and move times

  • I Include queue and move times
    Calculates the longest lead time of all components on the bill of material plus the queue days for the work center that is set up in the Work Center Maintenance (WCM) program and move days for all operations for this item's routing set up in the Routing Maintenance (RTM) program

  • N Do not update accumulated LT
    The item's item's accumulated lead time is not updated by the Accumulated Lead Time Calculation (MLT) program

If an item's LT Update field is I or E, the Accumulated Lead Time Calculation program calculates the accumulated lead time based on whether you make or buy the item. If the Make/Buy/Kit field in the item's record in the Enterprise Item Maintenance (IM) program is set to:

If Make/Buy/Kit is

Includes these lead times

M Make

Manufacturing, order preparation and put-away

B Buy

Order preparation, intransit, and put-away

K Kit

Lead times are not utilized for kits. Kit components have the same due date as the kit parent's expected ship date.

If the Make/Buy/Kit field is blank and the item has a low level code greater than one, the system considers it to be a Make item.

The LT Update field must be set for the parent item and for every component on its bill of material.

Beginning at the lowest level of a bill of material, the program takes into account the individual lead times of each component item. It calculates a critical-path lead time for each parent, then accumulates these lead times through successively higher levels. Finally, the program updates the Accum LT field in the Branch Item Maintenance (IMB) program.

For example, suppose that you have parent item 1-123 with components 1-1, 1-2, and 1-3 and these lead times.

Item

Make/Buy

Mfg LT

Order prep LT

Intransit LT

Put-away LT

Accumulated LT

1-1

B

 

0

1

0

1

1-2

B

 

2

90

1

93

1-3

M

1

1

 

 

2

1-123

M

2

1

 

 

96

For components, accumulated lead time depends on whether you make or buy the item. Accumulated lead time is a sum of the relevant lead time fields. For the parent item, accumulated lead time is the longest lead time of a component (in this example, item 1-2 with 93 days) plus the accumulated lead time for the parent item itself (Mfg LT +  Order prep LT + Put-away LT, which in this example is 3 days).

Accumulated lead time sets the time fence for planning programs.

Accumulated Lead Time Report

While updating accumulated lead times, the Accumulated Lead Time Calculation program prints a log of changes. Furthermore, the program offers the option of printing a log of proposed changes without actually changing accumulated lead times.

The report includes this information:

  • Branch

  • Item number

  • Engineering Change Level

  • Item description

  • MBK: M: Make, B: Buy, K: Kit

  • Quantity currently on purchase or manufacturing orders

  • For a parent item: If a make or kit  item: Order prep LT + Mfg LT + Put-away LT for the parent; if a buy item: zero  

  • Order prep lead time

  • Intransit lead time

  • Manufacturing lead time

  • Put-away lead time

  • Accumulated lead time before you ran the program

  • Accumulated lead time after you ran the program

  • LTI: The setting for the LT update field in the Branch Item Maintenance (IMB) program:

    I:

    Include the queue time for the work center set in the Work Center Maintenance (WCM) program and move time for the operation from the Routing Maintenance (RTM) program: Longest lead time of components on bill of material + Queue days + Move days

    E:

    Longest lead time of components on bill of material

    Blank:

    No calculation