7 Crucial Steps To Perfect Your Mix Model Line
- Techam Solutions
- 2 days ago
- 3 min read
Introduction
One of the core objectives for any manufacturer is maintaining high system efficiency and productivity to consistently meet customer demand. For companies producing multiple product variants on the same assembly line, this challenge becomes even more complex. Mixed-model production introduces variation in work content, cycle times, and labor requirements—and without a structured approach, this variation disrupts flow, increases waste, and reduces overall output.
Line balancing provides the solution. By evenly distributing work across stations based on takt time and production mix, manufacturers can create a smooth, predictable flow even when multiple product models run through the same line.
What Is Line Balancing?
Line balancing is the process of distributing work evenly across stations in an assembly line so each station has similar work content and products flow without delays, bottlenecks, or idle time.
In simple terms:Line balancing ensures every part of your assembly line works at the same pace.
When done right, it leads to:
Higher throughput
Reduced WIP (work-in-process)
Better labor utilization
Smoother workflow
Improved on-time delivery
Line balancing is also a core element of Lean manufacturing because it directly supports flow and takt time adherence.
Why Line Balancing Gets Harder in Mixed-Model Lines
Mixed-model assembly lines produce different products or variants on the same line, including optional configurations, sizes, or features.
This means:
Not every model has the same tasks
Work content fluctuates
Some stations get overloaded when certain models run
Small variations can create big flow problems
Good mixed-model line balancing is essential to avoid bottlenecks that slow down the entire system.
How Line Balancing Works in a Mixed-Model Environment
1. Calculate Takt Time
Takt time is the pace at which the customer demands finished units.
Takt = Available time / Total demand (across all models)
This becomes the heartbeat of the line.
2. Measure Work Content for Every Model- Production Planning Function
Each model—A, B, C, etc.—has unique cycle times. You capture this using:
Time studies
Standard work
Elemental task breakdowns
This gives you the real picture of variation.
3. Break Work Into Bill of Operations
Work must be broken down into repeatable, measurable elements.
For example:
Fit part
Weld component
Install feature
Test and verify
These elements become the building blocks for balancing the line.
4. Assign Tasks to Workstations
Tasks are distributed to stations based on:
Weighted average cycle time across models
Worst-case model
Shared tasks vs. model-specific tasks
Lean tools like Yamazumi (load balance) charts help visualize and balance workloads relative to takt time.
5. Smooth Production Using Heijunka (Model Sequencing)
In mixed-model lines, sequence matters. You don’t want all complex units at once. Instead of:
AAA BBB CCC
You create a leveled sequence like:
A B A C B A C B C
This reduces variation and keeps the line stable.
6. Use Flexibility Tools to Absorb Variation
Because mixed-model environments inherently vary, the best lines include flexibility such as:
Standard Work Combination Sheets
Float operators when certain units require extra work
Flexible manning plans
Option-specific micro-stations
Standardized materials and tooling
These tools ensure stability even when product mix shifts.
7. Continuously Improve and Rebalance
Demand, model mix, and processes change over time. For mixed-model lines, line balancing is a continuous improvement practice, not a one-time project.
Every improvement in cycle time or method becomes a new opportunity to rebalance and optimize flow.
Do you want to lean more about the topic?
Techam Solutions specializes in designing and implementing line balancing systems that support Lean transformation, operational excellence, and sustainable growth.
Contact us to schedule an assessment and explore how balanced flow can transform your operations.
