GR processing time in PP and MM
GR processing time in PP and MM
I have one material number that is procured externally but
also produced inhouse. Now I have one problem with the GR processing time.
A D V E R T I S E M E N T
As
far as I can see the parameter on the material master on MRP2 view and
Purchasing view is the same (MARC-WEBAZ). But in my case the GR processing time
should be only used for goods receipts in MM (from purchase oders). This GR
processing time must not be added to my lead time scheduled in production (when
producing the material). How to solve this conflict?
We have a make to order enviroment, that means our
production orders are created (and scheduled) directly from the sales order. The
sales gets back a confirmed date and quantity from production order scheduling -
and here this GR processing time is also added. Absolutely useless in this
scenario, but MM needs this GR processing time for the external procurement of
the material.
I'm hearing at least two problems here. Let me lumber through
them as I see them.
#1 - We have a make to order enviroment, that means our
production orders are created (and scheduled) directly from the sales order. The
sales gets back a confirmed date and quantity from production order scheduling -
and here this GR processing time is also added. Absolutely useless in this
scenario, but MM needs this GR processing time for the external procurement of
the material.
The GR processing time is quite legitimate, and needful. It
represents the time it takes once a material is 'delivered', before it is
usable. If that is instantaneous for you, then this field is blank. In fact if
it is less than one day, the field should be blank. (MARC-WEBAZ) If you DO have
to do testing or documentation or even just 'checking' to be sure the proper
certificates
have arrived with this material, then it's nice to have a day here for this. ---
I may have overlooked one thing, if you are ONLY thinking of the FERT that your
customer ordered, then maybe this field seems trivial. However, if your process
requires that the FERT be purchased from some other company (or even supplied
from within YOUR company), then there IS a receiving process that has to happen
. . . it does take time to back a truck up, get a fork truck to unload it, the
identification process, and then relocating the item to where it can be shipped
to your customer.
Also, if you produce this item, then there are 'other' items
that need to be 'built' into this item . . . THEY need the GR field, even if you
produce the saleable item, it has to be 'received' from production into
inventory for you to ship it out.
There is another field that should be considered. This is the
procurement lead time. The time it takes for purchasing to "react" to the
requirement. When the sales order is placed, the signal will come for
'purchasing' to occur (via MRP perhaps). Purchasing MAY take as long as a day to
get that order to a vendor where the vendor can now react. This time is
generally a 'standard' time for any given plant/purchasing org and is included
using OMDT.
Thirdly, the vendor lead time has to be considered. This is
what the field "Planned delivery time" (MARC-PLIFZ) is about. The vendor's turn
around time - from the time they are notified of your intention (via a PO
perhaps), until they can put it on your dock . . . that is what this field is
about. And MRP knows the difference between this field and the others. Between
the three fields mentioned, the 'purchased' item is properly planned for . . .
except for the exceptions and the fact that this is all based on "norms" and
averages which never seem to be exactly what is needed, but that's another
discussion .
Next we think of the situation where the item requested is
produced by us. In this case (as mentioned before), the GR is STILL legitimate -
perhaps not needed if it takes less than a day for your company to receive
material from production, inspect it, certify it, and load it up.
However, a "0" is a legitimate entry to this field.
What is also needed is a place to locate the time for
"producing" this item. That is where there are options. One option in MRP 2 is
the field "in-house production" (MARC-DZEIT). This is sometimes useful, but
dangerous. It assumes that no matter how large an order is or how much of a
material is needed, it can always be produced in the same period (in 'days', of
course). The number of days fits in this field.
If that doesn't 'do it' for you, you can go to the "Work
Scheduling" view of the Material Master and include the details for the fields
under the "in house production time in days" grouping (Setup time;
Interoperation; Processing time; and base quantity). At LEAST this gives the
system a 'shot' at planning longer times for greater quantities. If you fill
both data points in (in
house production time and " in days, the 'in days' will supercede the other).
Now you've put in all the data that you HAVE to input to have
the system plan the length of time needed for telling your customer when you
will have their product ready for them.
In the case of your conflict where you produce OR source the
item, then you MAY have a problem with GR - look at both scenarios and see what
your entry should be. You CAN use the Total Replenishment Leadtime (MARC-WZEIT)
field to be the TOTAL TIME when producing the material in-house, because the
external replenishment does not look at this field. So MRP will run and
depending on how you have it set, it will consider purchasing the material, or
making the material, and the fields we've mentioned will impact the result as
mentioned.
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