Oracle Manufacturing Lead Time Guide-1

Subject:  Oracle Manufacturing Lead Time Guide
  Doc ID:  Note:100127.1 Type:  WHITE PAPER
  Last Revision Date:  02-NOV-2007 Status:  PUBLISHED

PURPOSE
-------
This document serves as a guide to Oracle Manufacturing Leadtimes.  It answers
the following questions:

      1.  How are leadtimes, in Oracle manufacturing applications, used?
      2.  How are leadtimes maintained?
      3.  How do leadtimes impact other processes?
      4.  How are leadtimes defined?

SCOPE AND APPLICATION
---------------------
This document contains numerous facts and information on leadtimes used in
Oracle Manufacturing Applications and is intended for anyone having a need to
setup or understand the functionality of Oracle Manufacturing Leadtimes.

ORACLE MANUFACTURING LEADTIMES GUIDE
-------------------------------------

1.  BASIC MAINTENANCE.

      a.  The workday calendar must be setup correctly and rebuilt any time
      modifications are made to the calendar.

              Navigation paths: Bill of Materials/Setup/Calendars
                                                  Inventory/Setup/Organization/Calendars

      b.  Once you have made your modifications, you need to rebuild the calendar
      by selecting the special option on the top tool bar.  On the drop down list,
      click on build.

      c.  Any time you make changes to a routing or resource, you should
      recalculate and rollup the leadtimes.

              Navigation path: Bill of Materials/Routings/Leadtimes

 
2.  GENERAL FACTS

      a.  For an item to have manufacturing leadtimes calculated, it must be a
      make item.  Leadtimes are not calculated for purchased items even if they
      have a routing.

              1)  Navigation path: Inventory/Items/Organization Items.
              2)  Select the General Planning alternate region.
              3)  Choose the make option for make or buy. 

      b.  Set the scheduling option for the operation resources to yes.
 
              1)  Navigation path: Bill of Materials/Routings.
              2)  Put the cursor on the desired operation sequence.
              3)  Click on the [Operation Resources] button.
              4)  Select the desired resource sequence with your cursor.
              5)  Select the Scheduling alternate region.
              6)  Select the Yes option for schedule.   

      c.  If you want to use a fixed leadtime for a resource, you need to use a
      basis of Lot.

              1)  Navigation path: Bill of Materials/Routings.
              2)  Put the cursor on the desired operation sequence.
              3)  Click on the [Operation Resources] button.
              4)  Select the desired resource sequence with your cursor.
              5)  Select the Main alternate region.
              6)  Select the lot option for the basis.           

      d.  If you want to use a variable leadtime for a resource, you need to use
      a basis of Item.

              1)  Navigation path: Bill of Materials/Routings.
              2)  Put the cursor on the desired operation sequence.
              3)  Click on the [Operation Resources] button.
              4)  Select the desired resource sequence with your cursor. 
              5)  Select the Main alternate region.
              6)  Select the item option for the basis.

      e.  If you put a number in the assigned units field, other than the number
      1, which is defaulted, the scheduler will divide the leadtime for that
      resource by the number of assigned units for the resource entered and use
      the fractional leadtime in the leadtime roll up.  The assigned units
      field tells the scheduler how many resources/machines you have available
      to the job in order to complete it in less time.  In other words,
      if you enter a 2, the leadtime for this resource will be cut in half.
      If you enter a 3, the leadtime will be one third and so on.

              1)  Navigation path: Bill of Materials/Routings.
              2)  Put the cursor on the desired operation sequence.
              3)  Click on the [Operation Resources] button.
              4)  Select the desired resource sequence with your cursor.
              5)  Select the Scheduling alternate region.  Here you can change the
                      number of assigned resources that you want for this resource.

      f.  MRP expects that you will receive material due into inventory by the
      beginning of the business day on which it is due.  You may wish to consider
      receiving it into inventory at the close of business on the previous day.
      Simply change your receiving function to accommodate this.

      g.  MRP will use the fixed leadtime if entered.  This can be manually
      entered into the organization item form in inventory.

              Navigation path: Inventory/Items/Organization Items

      h.  Fixed leadtime is automatically entered if you do the Leadtime
      Rollup.  If you manually enter the fixed leadtime, it will be over-
      written whenever someone does a leadtime rollup.

      i.  When doing a leadtime rollup, there is no validation for items if you
      select a range of items.  If you select a specific item,  it validates
      that item and, if it does not have a bill, it does not calculate any
      leadtimes.

      j.  To set up a variable leadtime for a resource that can complete
      one unit every ten minutes:

              1)  Navigate to Bill of Materials/Routings/Routings.
              2)  Query up a routing.
              3)  Put your cursor on the desired operation.
              4)  Click on the [Operation Resources] button. 
              5)  Enter the resource sequence and the name of the resource that
                      will do the work.
              6)  Make sure the Unit of Measure (UOM) that defaults is correct. 
                      In almost all cases it should be hour (HR). 
              7)  Select Item from the drop down menu for basis.
              8)  Enter six (6) in the Inverse column under rate or amount.  You have
                      now told the system that you can do six items per hour or one unit
                      every ten minutes.

      k.  Oracle WIP uses WIP Detailed Scheduling and Repetitive Line Scheduling
      to determine order start date.  Therefore, it is conceivable that MRP and
      WIP could recommend different starting dates to meet the same requirement
      due to the more refined method of order start date calculations in WIP.

      l.  Oracle starts calculating the leadtime at 12:00AM or the start time
      of the first defined shift for the day.

      m.  The Oracle lead time calculation considers shift timing and gaps
      betwen the shifts.  Calculations are based upon the second.

      n.  Any time-based resource will be converted and rounded to the number of
      seconds.  The converted value has to be at least one second in order to be
      calculated.  The rounding to number of seconds is by design.  For
      non-time-based resources, the conversion rate is zero and will not have
      any effect on leadtime calculations.  For example, WIP (the application
      which actually does the calculation), converts a usage rate of .000018 of
      an hour to .0648 seconds (.000018 x 3600 second in an hour) which is then
      rounded to 0.  The code will not work if the precision is below a second. 
      This is standard functionality.

      o.  When doing forward scheduling, you have to schedule the resource
      based on the shift hours (using start and stop times), workdays and
      non-workdays, the start date and time of the lot and the usage rate of the
      resource.  In doing this, any elapsed or idle time, due to a resource not
      being available to work, will be added to the leadtime.  Depending on the
      size of the lot being processed, you could have a wide variety of
      completion dates and times.  For example:
 
              -  You have a resource that can process one unit per hour and is
                    available from 8:00 to 4:00.
              -  A lot of three units will be moved to the next resource at 11:00.
                    The leadtime for this lot is .125 days for this resource.
              -  A lot of 10 cannot be moved to the next resource until 10:00 the
                    next day.  This lot will then have a leadtime of 1.0833 days for
                    this resource.

      p.  Dynamic Leadtime Offsetting is the estimation of the start date of an
      order, operation or a resource, based on the order quantity, leadtimes and
      the workday calendar.  Depending upon the number of units, volume and usage
      rate, the leadtime could be rounded to zero.

      q.  Detailed Leadtime Scheduling calculates jobs to the second based on
      resource units available and the usage rates.
 
      r.  Using a leadtime lot size greater than one will give a more accurate
      variable leadtime.  It should reflect the average lot size that will be
      processed.

      s.  The Available 24 Hours checkbox on the resource schedule will ignore
      manufacturing calendar days off if checked.

              1)  Navigation path: Bill of Materials/Routings.
              2)  Put the cursor on the desired operation sequence.
              3)  Click on the [Operation Sequence] button.
              4)  Select the desired resource sequence with your cursor.
              5)  Select the Scheduling alternate region.

      t.  Repetitive Line Leadtimes include:

              1)  Fixed line or routing based leadtimes.
              2)  Processing leadtime.
   
      u.  Calculating the Leadtime of Purchased Items. 

              1)  Your workday calendar IS included when calculating any lead-
                      times for purchased items.

              2)  The purchased items leadtime is calculated as follows:

                              Postprocessing Leadtime (time needed to move from receiving
                                                                                  to inventory)
                                    +
                              Processing Leadtime (time vendor needs the order before
                                                                          delivery to your dock)
                                    +
                              Preprocessing Leadtime (purchase order preparation)

              3)  The results are:

                              The dock date (found on the Planning Detail Report) is the date
                              by which the vendor should deliver the material to your dock.

                                      Dock Date = Order Due Date - Postprocessing Leadtime

                              The start date is the date by which you should give the sales
                              order to your vendor.
 
                                      Start Date = Dock Date - Processing Leadtime

                              The order date is the date by which you should start your
                              purchase order.

                                      Order Date = Start Date - Preprocessing Leadtime

              4)  You can assign values for fixed leadtime instead of assigning
                      the processing leadtime.       

      v.  Calculating the Leadtime of Manufactured Items:

              1)  Fixed Leadtime (time your shop floor needs to manufacture the
                      item or complete the job).

                              Fixed leadtime  = 
                              lot time (usage rate or amount) / assigned units

              2)  Variable Leadtime (time your shop floor needs to manufacture
                      each item - each piece * variable leadtime)
 
                              Variable leadtime =
                              total lot time + ((item based time * lot size) assigned units)

              3)  The planned order order date is the date by which you need to
                      start the process of creating a discrete job or repetitive line. 
                      It is calculated as follows:

                              Planned order order date =
                              planned order order date - preprocessing leadtime

              4)  The planned order due date is the date by which the item is needed.
                      It is similar to the dock date for a purchased item.
 
              5)  The planned order start date is the date by which you need to
                      release a discrete job or start a line.  It is calculated as
                      follows:

                              Planned order start date =
                              planned order due date - leadtime offset

                      The leadtime offset is used as follows:
 
                              Planned order due date - leadtime offset =
                              planned order order date

                      The leadtime offset is calculated as follows:

                              Leadtime offset =
                              Fixed Leadtime + (Variable Leadtime * Order Quantity)