Hello Odoo Community 👋,

I’m using Odoo 18 Community Edition, and I’ve found a possible bug in the Manufacturing (MRP) module related to Work Order Expected Duration calculation.

Steps to Reproduce

1. Create a Work Center
   • Capacity = 1
   • Time Efficiency = 100%
   • Working Hours = Standard 40h/week
2. Create a BoM
   • Product Qty = 1000
   • Add one Operation → Duration Computation = Set duration manually
   • Duration (minutes) = 60
   • Work Center = the one created above
3. Create a Manufacturing Order
   • Product Qty = 2000
   • Confirm and check Work Orders tab

Actual Result

• The Expected Duration field shows a very large number (e.g., 120000:00) instead of the correct 120 minutes (2 hours).

Expected Result

• Expected Duration should be 2 hours (since BoM = 1000 → 60 min, MO = 2000 → double quantity).
  
  

📊 Comparison of All Scenarios (BoM 1000 Qty / Duration 60 min / MO 2000 Qty)

Hypothesis

• It seems Odoo treats the BoM operation “Duration (minutes)” as hours (or seconds) internally when computing duration_expected.
• Possibly an issue in addons/mrp/models/mrp_workorder.py under _get_duration_expected or _plan_workorders.

Correct formula should be:

cycles = math.ceil((mo_qty / bom_qty) / max(capacity, 1))
expected_minutes = cycles * duration_minutes
duration_expected = expected_minutes / 60.0

Environment

• Odoo 18.0 CE (fresh DB, no custom MRP changes)
• Manufacturing module only
• Tested on Linux + PostgreSQL 15

Request

Could someone from Odoo or the community please confirm whether this is a known bug or a new regression in Odoo 18 CE?

If confirmed, I’d like to raise a GitHub issue or propose a small patch.