How is the line constraint model built and maintained?

The line constraint model is configured in HublerX by the planning team — the approved product list per line is loaded from the ERP product master and engineering records; line speeds per SKU are taken from production standards; the changeover matrix is built from historical changeover records and the process engineering team's input. The model is reviewed and updated when lines are modified, new products are approved, or changeover standards change.

Can the schedule optimisation handle minimum run quantities?

Yes. Minimum economic run quantities — configured by line and product to account for the cost of a changeover relative to the batch size — are enforced during schedule generation. WOs below the minimum run quantity are either combined with an adjacent run of the same product or flagged for the planner to review before the schedule is issued.

How does HublerX handle a WO that can only run on a line that is already at capacity?

Where a WO's only approved line is at capacity during the required window, HublerX surfaces the capacity conflict with the specific WO competing for the same line time, the impact on the delivery due date, and the options — prioritise this WO and defer another, add overtime to the line, or negotiate a revised delivery date. The planner resolves the conflict; HublerX updates the schedule.

Can the constraint model handle multi-stage production where a product goes through two lines?

Yes. Multi-stage production routes — where a product is, for example, baked on Line 1 and then packed on Line 3 — are configured as a sequence of operations in HublerX. The schedule coordinates both stages, ensuring the downstream line has capacity available when the upstream stage completes, with the configured inter-stage buffer time accounted for.

Production Scheduling with Line Constraints

The Problem

The ERP schedule says the job fits on Line 3. The shopfloor knows it cannot run on Line 3.

Production schedules generated from MRP or capacity planning tools typically operate on simplified models of production capacity — total available hours on a line, minus a utilisation factor. They do not reflect the real constraints that the shopfloor works with: Line 2 cannot run SKU-X because the tooling is not approved for that product. Line 3 runs at 60% of Line 2's speed for a specific pack format. The changeover from Product A to Product B on Line 1 takes 3 hours, not 45 minutes. Allergen sequencing rules mean that the order of jobs on Line 4 cannot be changed without a full cleaning protocol.

When a schedule that ignores these constraints reaches the shopfloor, the production supervisor spends the first 2 hours of every shift resequencing the jobs — moving work to the right line, adjusting for changeover time, fixing allergen sequence violations — before production can start. The plan that was issued is not the plan that gets executed. And the planning team finds out at the end of the shift, not at the beginning.

Current Workaround

What most operations do today: Most operations today: the planning team generates a schedule from the ERP using capacity hours, and the production supervisors adjust it manually at the start of each shift using their knowledge of which lines can run which products and in what sequence. The adjusted schedule is not fed back to the planning system — it lives on the shift whiteboard. The gap between the ERP schedule and the executed schedule grows through the week as supervisors make adjustments that the planner does not see.

The HublerX Approach

A constraint-aware production schedule is built from a model of the factory that reflects how it actually operates — not how it was modelled in the ERP during implementation. HublerX maintains a line constraint model for each production line: the approved product list, the line speed by SKU and pack format, the changeover matrix between products, the allergen sequencing rules, and the minimum run quantity. The schedule is generated from this model — producing a plan that is executable as issued, without requiring shopfloor adjustment.

How It Looks in HublerX

Live workflow view

Line Schedule Board

4 lines · 18 WOs today

CONSTRAINT VIOLATION2

WO-4893 · Allergen sequenceLine 4 · Peanut after Nut-freeAllergen violationResequencePeanut must run BEFORE nut-free · Full clean required

SCHEDULED · VALIDATED4

Line 1 · 5 WOs · 2 shiftsGlucose Biscuits → Marie Light → DigestiveValidatedChangeover matrix optimised · 2h total changeover

Line 2 · 4 WOs · 1.5 shiftsCream Cracker → Wheat BiscuitsValidatedAllergen free block · No cleaning protocol needed

Line 3 · 3 WOs · 1 shiftButter Cookies → Choco ChipValidatedShort changeover 45 min between variants

Line 4 · 4 WOs · 2 shiftsPeanut Cookies (first) → Glucose BiscuitsValidatedAllergen sequence correct · Protocol P-03 at changeover

IN PRODUCTION4

Line 1 · WO-4871 · Glucose BiscuitsStarted 6:00 AM · 4,800 u/shift · 70% doneRunningOn schedule · Next: Marie Light at 10:30 AM

Line 2 · WO-4873 · Cream CrackerStarted 6:00 AM · 3,600 u/shift · 60% doneRunningOn schedule · Next: Wheat Biscuits at 11:00 AM

Line 3 · WO-4875 · Butter CookiesStarted 7:00 AM · 3,200 u/shift · 50% doneRunningOn schedule · Next: Choco Chip at 2:00 PM

Line 4 · WO-4877 · Peanut CookiesStarted 6:00 AM · 2,400 u/shift · 80% doneRunningAllergen run first · Protocol P-03 ready · 10:00 AM

COMPLETED TODAY2

Line 1 · WO-4861 · Digestive MiniCompleted 5:30 AM · 2,400 unitsCompletedOn schedule · QC cleared · FG store

Line 3 · WO-4863 · Marie LightCompleted 6:45 AM · 3,600 unitsCompletedOn schedule · QC cleared · FG store

How HublerX Coordinates It

The step-by-step sequence

1
Line constraint model maintained
HublerX maintains a line constraint model for each production line — the approved product and SKU list, line speed by SKU and pack format, changeover time matrix between product families, allergen sequencing rules, and minimum economic run quantities. The model is maintained by the planning team and updated when lines are modified or new products are approved.
Configuration · updated on change
2
Production demand loaded from confirmed WOs and forecast
HublerX loads the production demand — confirmed customer orders converted to work orders, plus forecast demand for the planning horizon. Each WO specifies the SKU, the quantity, and the required completion date. No line assignment is made at this stage — HublerX assigns lines based on the constraint model.
On planning run
3
WOs assigned to feasible lines
HublerX assigns each WO to the lines on which it can be produced — based on the approved product list in the constraint model. Where a WO can be produced on multiple lines, HublerX assigns it to the line that minimises overall changeover time and maximises throughput across the plan horizon.
On schedule generation
4
Sequence optimised for changeover and allergen rules
Within each line, HublerX sequences the WOs to minimise total changeover time — grouping products with short changeovers between them and scheduling allergen-containing products before allergen-free products. The changeover matrix drives the sequence, not the order in which WOs were received.
On schedule generation
5
Schedule validated against all constraints
HublerX validates the generated schedule against every line constraint — no unapproved product on a line, no changeover below the minimum time, allergen sequence rules respected, minimum run quantities met. Violations are flagged with the specific constraint breached and a suggested resolution.
On schedule generation
6
Executable schedule issued to shopfloor
The validated schedule is issued to the shopfloor — each line receives a sequenced list of WOs with start times, changeover windows, and quality checkpoint prompts at the right intervals. The shopfloor executes the plan as issued. Deviations are captured in HublerX and fed back to the next planning cycle.
On planner approval · before shift start