What is a two-bin system and how does it work?
A two-bin system is the easiest way to implement a kanban system into a manufacturing or production facility. Kanban is a methodology in lean manufacturing which manages and improves workload within production. Originally developed in Japanese automotive factories, the word ‘Kanban’ can be roughly translated to mean ‘Visual Signal’ and is used as a Just-In-Time (JIT) method of inventory control.
The aim of a Kanban System is to eliminate excess inventory throughout the production cycle and align inventory levels with actual consumption, whilst highlighting any inefficiencies within the supply chain.
A two-bin system is actually exactly what it claims to be – managing inventory through the use of two-bins. The concept of a two-bin system is that operators will feed from one bin whilst using the second bin for reserve stock. Once the first bin has been exhausted of contents the operator will start feeding from the reserve stock whilst triggering a signal that more stock is required. The signal can be as simple as the colour of the bin or as complicated as RFID signals being sent to receivers and automatically placing an order with suppliers. Once the next batch of stock is available, it is simply placed back into stock for the operator to work from once the current batch is exhausted. The two-bin system creates a cycle, replenishing when required whilst creating a demand for the next batch – if implemented correctly, it should mean you are one step ahead of your requirements.
Benefits of a two-bin system
There are many benefits that can be seen when utilising a two-bin system, which can include:
- Reducing inventory held and therefore the associated costs
- Traceability of stock
- Easy to maintain once installed if appropriate planning is maintained
A reduction of inventory held is a positive byproduct that can be seen when implementing a two-bin system, because only holding the stock you need means that you haven’t got finances tied up in stock that isn’t being utilised for weeks or maybe months, whilst also promoting traceability of parts through batch control which is stored in each bin. Once all the planning is complete, it is important to monitor aspects that may affect the two-bin system, such as spikes in manufacturing which may lead to a higher demand for stock. A two-bin system can fail if insufficient planning has taken place. It is often advised to understand the demand for the product and ensure that all reserve batches contain enough product, whilst taking into consideration the lead-time of the next batch.