Thriving in manufacturing isn’t always easy, especially when the landscape is evolving constantly. But shifting from conventional production systems to one piece flow can help, especially to reduce waste, boost efficiency, and churn out products of better quality faster.
Traditional systems, as you know, involve big batches where items are group-produced before they move to the next stage. Though this approach is apparently efficient, problems are often detectable later in the form of inventory buildup, delays, and subpar quality.
One piece flow, a powerful lean manufacturing principle, is an alternate approach that involves the production of items in a continuous stream and one at a time. Since it focuses on individual units moving smoothly through a manufacturing process, one piece flow minimizes inventory, cuts down waiting time, and allows teams to spot problems promptly.
Consequently, the production flow becomes seamless and more in line with customer demand. So, if you have lean production on your mind, here’s everything to know about one piece flow.
What Is One Piece Flow? Definition and Benefits in Manufacturing
In conventional batch production, a workstation might churn out hundreds of units before pushing them to the next stage. However, one piece flow is a method of production wherein items don’t move in batches, but rather one unit at a time. Each product transitions from one step to the subsequent without having to wait for a large batch of items to get finished first.
A key aspect of continuous flow manufacturing, one piece flow ensures the steady movement of materials and products through the system almost without any interruption. Production steps are synchronized, so every item heads towards the next operation right after it’s completed.
The one piece flow method helps in:
- Getting rid of waste
- Reducing work in progress (WIP)
- Bettering quality
- Shortening the cycles of production
- Meeting customer demands more quickly
You can maintain a stable and predictable production flow besides creating an environment that’s agile and responsive.
One Piece Flow vs Batch Production
When moving towards lean production, it’s crucial to understand how one piece flow is different from batch production.
Batch Production
Items are manufactured in groups before they pass on to the next stage. For instance, a machining station might churn out 500 components, after which the entire batch is pushed to assembly. Assembly then processes the entire batch before the latter is sent to the next stage.
This approach reduces changeovers and simplifies scheduling. However, it triggers operational hiccups like:
- Long queues in between stages of production
- Large amounts of WIP
- Delayed identification of quality defects
- Extended production lead times
So, even if a defect crops up early on in a batch, it might be discovered after hundreds of units are already produced.
One Piece Flow
Products, in this case, move as individuals through the manufacturing system. For instance, after a single component is machined, it moves to assembly immediately. And the machining of the next component starts.
The continuous movement ensures that large intermediate inventories don’t accumulate and production flow is smooth. One piece flow offers perks like:
- Rapid spotting of defects
- Lower levels of inventory
- Shorter lead times
- Greater responsiveness to the demands of customers
However, you might have to alter layout, process design, and workforce coordination. It’s still worth the investment and effort.
The 5 Benefits of One Piece Flow in Production
Implementing one piece flow successfully means you can look forward to significant operational improvements:
- Faster Production Lead Times
Since items move in between processes directly, the waiting between stages is noticeably less than usual. Hence, total production time is reduced and you can fulfil customer orders more quickly.
- Better Quality Control
Defect detection is almost immediate in one piece flow. If an issue rears its ugly head in one stage, the next step reveals it right away. Defective units don’t get to progress through the system, which reduces scrap or expensive rework.
- Lower WIP Inventory
It’s common for large amounts of WIP inventory to sit in between workstations in case of batch production. However, one piece flow enables items to continuously move rather than pile up in queues. This reduces WIP substantially. And lower inventory is associated with healthier cash flow, lower storage costs, and greater visibility into production performance.
- Improved Alignment with Customer Demand
Especially when paired with just in time manufacturing (JIT) principles, one piece flow turns out to be highly effective. The combination helps synchronize production with takt time, the speed necessary for satisfying customer demand. Hence, you can generate exactly what customers require and that too at the right time.
- More Process Visibility
Continuous movement through the manufacturing system improves problem visibility. You can more easily spot delays, bottlenecks, inefficiencies and address them quickly, as a part of lean improvement efforts.
Common Challenges of One Piece Flow in Production
When transitioning from batch production to one piece flow, many manufacturers experience these challenges:
Equipment Limitations
Certain types of manufacturing equipment are particularly designed for batch production, like tanks for processing chemicals, large furnaces, and heat treatment systems. And to operate efficiently, these pieces might need multiple units. Hence, without process redesigning, implementing one piece flow can be difficult.
Changeover Time
If setup times for machines are lengthy, churning out one unit at a time might lower efficiency. Lean tools like Single-Minute Exchange of Dies (SMED) can resolve this issue though.
Layout Restrictions
Traditionally, factories tend to be organized by machining, assembly, inspection, and packaging departments. And this layout is conducive to batch production since items must travel significant distances in between departments. So, reorganizing workstations into cellular layouts is often essential to facilitate one piece flow or continuous movement.
Employee Training
To successfully implement continuous flow manufacturing, workers need to be cross-trained so they can operate various tasks inside a single production cell. You might have to alter workforce responsibilities too.
How to Scale One Piece Flow in Multi-Site Operations
Moving to one piece flow in just one factory can often be daunting. So, scaling to multiple sites can amplify complexities. That’s because every facility might be operating with different production volumes, equipment, management practices, and employee skills.
So, you need a structured approach to ensure consistent production flow across factories:
Standardize Processes
When different factories follow different processes, it’s tough to maintain a consistent manufacturing system. So, put together clear and standard work instructions, document processes visually, and introduce training programs that define how tasks must be conducted.
Ensure standards cover workflow design, layouts of workstations, material handling, and quality checks. Then every site will run on the same operational principles. You can maintain stable one piece flow and replicate effective improvements across plants.
Line Up Production with Takt Time
Production must sync with takt time for one piece flow to work. However, when operations are spread across multiple sites, demand signals originate from central planning systems while execution occurs locally. And production imbalances happen when every facility has a different interpretation of demand.
So, you must align process capacity, staffing levels, and production schedules with takt time across factories. In JIT environments, this alignment particularly matters, to minimize overproduction and excess inventory.
Carry Out Continuous Improvement Programs
Without ongoing improvement efforts, even the best production systems grapple with bottlenecks, variations, and new operational hiccups over time. So, encourage local teams to be a part of continuous improvement initiatives like problem-solving workshops and Kaizen events.
When frontline workers are empowered to detect inefficiencies and suggest improvements, it’s easier to maintain lean production systems. And as operations expand, one piece flow keeps evolving too.
Share Best Practices across Factories
Multi-site operations offer the unique opportunity to learn from different sites and share important lessons too. For instance, if one factory optimizes workstation layout or boosts production flow, other sites experiencing similar challenges can learn from it.
You can ease the sharing of knowledge through platforms for internal collaboration, operational benchmarking, and cross-site improvement reviews. This way, proven solutions are replicated faster and lean manufacturing practices are strengthened network-wide.
Leverage Operational Visibility in Real Time
Clear visibility into the performance of all factories is essential for scaling one piece flow. So, track metrics like WIP levels, cycle time, downtime, and production throughput across locations. Otherwise, it might be tricky to spot where flow disruptions are happening.
The above exercise can help you address production flow issues before they magnify. Transparent sharing of operational data also drives more effective collaborate across teams.
Lean Tools That Support One Piece Flow
To implement one piece flow and sustain it, use these lean manufacturing tools:
Value Stream Mapping (VSM)
With VSM, you can visualize the complete manufacturing process. Moreover, teams can detect waste, delays, and inefficiencies that disrupt the flow of production.
Cellular Manufacturing
Production cells group together workstations that are related, so movement is minimized and product flow is continuous.
Kanban Systems
Kanban signals help in regulating the movement of materials in between different processes. When paired with JIT, Kanban helps maintain a stable production flow and averts overproduction.
Standard Work
Standardization makes sure that tasks are carried out efficiently and consistently. Besides reducing variability, standard work ensures one piece flow operations are steady.
SMED
You can easily switch between products when setup time is reduced. And SMED helps with just that. Production runs are smaller and flow is continuous.
How Digital Tools Help Sustain One Piece Flow
If lean manufacturing excellence is what you are after, implementing one piece flow can do the trick. From greater quality control to better alignment with customer demand, the benefits are multiple. However, scaling one piece flow across multi-site, complex operations requires constant monitoring, coordination, and adequate visibility. Fortunately, digital tools can help.
Fabriq, for instance, can help you track key metrics, monitor performance, and drive continuous improvement initiatives in real time. You can also connect frontline workers with operational data and performance dashboards, ensure greater transparency, and spot and fix production flow disruptions swiftly.
So, get ready to give your organization a more competitive and agile makeover with one piece flow.
Reach out to see how Fabriq can help you implement and scale one piece flow.
