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Scrap % for MRP Only

  • 1.  Scrap % for MRP Only

    TOP CONTRIBUTOR
    Posted 12 days ago
    Hi All

    Trying to figure out how to get the correct raw material requirements and not have extra consumption

    So here's our scenario

    We grow plants and they go through several phases of several weeks each

    We are using routing link codes with backflushing, so when we post output of an operations the components, get consumed. That all works great

    So let's say phase 1 takes 4 week and typically has a 30% loss

    So we setup the BOM components for phase 1 to all have 30% scrap. MRP works great: gives me 30% extra inputs.

    Assuming I want 100 plants and there's a 1:1 ratio between the items and the components, 100 plants requires 130 to be planted

    So we carry out the planting and our output qty is 130 (what we planted) and we mark it finished, so the task disappears. We may yield 100, 110, 120

    The problem is, when I post my output of 130, it's consuming 30% on top of that. Even if I just posted output of 100, it's still posting scrap, but we won't know for several weeks, how many were scrapped, but that doesn't even help me,as I may get more than 100 out. Whatever we yield, the minute we plant we will use exactly 130 and need to consume that out of inventory, so I need total consumption to be 130

    So is there a way to enter a scrap value of 30% for the MRP calc only

    ------------------------------
    Mark Anderson
    Director of ERP Systems
    Clesen Wholesale
    Evanston, IL
    ------------------------------
    Academy - Online Interactive Learning from Experts


  • 2.  RE: Scrap % for MRP Only

    TOP CONTRIBUTOR
    Posted 9 days ago
    I have some preliminary questions:
    • Why are you posting output before you know what the final output quantity is?
    • Why are you back flushing you components when you have variable scrap?

    I would suggest that you:
    • Include 30% scrap in your BOMs.
    • You change flushing to manual.
    • You post consumption based on your actual planting.
    • You keep the production order open until you get final output (plants completed at that stage), then you post the actual output. This de-couples the output from consumption.

    The result will be that you have the correct consumption (quantities and date) and the correct output (quantities and date). MRP will continue to plan based on your 30% scrap, but actual production will rely on what is actually consumed.

    ------------------------------
    Andrew Good
    President
    Liberty Grove Software
    Oakbrook Terrace IL
    ------------------------------

    Academy - Online Interactive Learning from Experts


  • 3.  RE: Scrap % for MRP Only

    TOP CONTRIBUTOR
    Posted 9 days ago
    Hi Andrew

    thanks for the reply. some answers below

    I have some preliminary questions:
    • Why are you posting output before you know what the final output quantity is?
      • As soon as we plant, the materials are gone from inventory, so we need to consume them as we use them (regardless of whether they are good in 4 weeks, the inventory is gone).  We don't know the scrap until weeks later and there usually 2 more several week phases, so the production order will be open for 10-14 weeks. (this is not final output tn inventory)
    • Why are you back flushing you components when you have variable scrap?
      • we don't want user to have to post output of components individually, so back flushing is ideal

    I would suggest that you:
    • Include 30% scrap in your BOMs.
    • You change flushing to manual.
    • You post consumption based on your actual planting.
    • You keep the production order open until you get final output (plants completed at that stage), then you post the actual output. This de-couples the output from consumption.

    I figured out a solution at weekend

    I added scrap to routing instead of BOM
    This doesn't post any scrap for the operations, but generates demand for the components
    When a planting phase finished some weeks later, we can just post a negative output qty and a positive scrap qty to account for scrap. Works well and that's how I've done it in other manufacturing environments

    thanks for suggestion

    Mark

    ------------------------------
    Mark Anderson
    Director of ERP Systems
    Clesen Wholesale
    Evanston, IL
    ------------------------------

    Academy - Online Interactive Learning from Experts


  • 4.  RE: Scrap % for MRP Only

    TOP CONTRIBUTOR
    Posted 9 days ago
    Did you try forward flushing?

    ------------------------------
    Gregory Alford
    Director of Technical Resources
    Tri Star Metals LLC
    Aurora IL
    ------------------------------

    Academy - Online Interactive Learning from Experts


  • 5.  RE: Scrap % for MRP Only

    TOP CONTRIBUTOR
    Posted 9 days ago
    Thanks greg

    I figured out a solution at weekend

    I added scrap to routing instead of BOM
    This doesn't post any scrap for the operations, but generates demand for the components
    When a planting phase finished some weeks later, we can just post a negative output qty and a positive scrap qty to account for scrap. Works well and that's how I've done it in other manufacturing environments

    thanks for suggestion

    Mark

    ------------------------------
    Mark Anderson
    Director of ERP Systems
    Clesen Wholesale
    Evanston, IL
    ------------------------------

    Academy - Online Interactive Learning from Experts


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