Planning, Sequences & Comparisons¶
Planning semantics¶
PyExtrusion separates the physical process from the quantity requested.
A process describes how the profile is extruded.
A planning request describes how much output is required.
Public planning requests can be expressed as:
- finished bars;
- good kilograms;
- good metres;
- exact number of billets;
- available technical press time.
Whole billets¶
Operational planning works with complete billets.
A request may therefore produce slightly more finished output than the exact requested quantity because the final billet is still manufactured as a whole billet.
Time-window planning¶
When a user provides an available press-time window, PyExtrusion determines how many complete billets can be completed within that technical time.
It does not count a partially completed billet as finished production.
Production sequences¶
A production sequence is a user-supplied ordered list of production orders.
PyExtrusion:
- preserves the supplied order;
- calculates each order using the normal planning engine;
- accumulates the technical press time;
- can expose cumulative or theoretical start/end positions.
PyExtrusion does not:
- reorder the sequence;
- insert setup assumptions;
- add die-change time;
- add waiting time;
- account for shifts or weekends;
- infer die availability;
- optimise the schedule.
Therefore:
a production sequence is a continuous technical calculation, not a guaranteed plant schedule.
Multi-press comparison¶
PyExtrusion can evaluate the same technical case across two or more presses.
The comparison principle is deliberately neutral:
the same supplied process or production sequence is calculated independently for each press.
The library can expose differences such as:
- viable / not viable;
- supported / unsupported;
- extrusion ratio;
- billet requirement;
- pulls and billets;
- good output;
- process losses;
- technical time;
- net productivity;
- warnings.
PyExtrusion does not automatically select a winner, allocate orders among presses or modify the sequence to improve a result.