Two-stage picking

What is two-stage picking?

Two-stage picking is a picking process in which order control and picking do not take place immediately, but in two stages. Depending on the warehouse type and storage zones, the orders are first picked cumulatively by the picker and then distributed to the individual orders at the packing station. The process is often supported by a sorting system.

How exactly does the process work?

The prerequisite for two-stage picking is a certain quantity of individual customer orders (goods) that can be combined into a total order (order pool or batch).

The merchandise management or warehouse management system accumulates the orders together and calculates the optimum combination of orders. The volume of items and containers must also be taken into account in this picking process.

The storage type is decisive for the management, or more precisely for the wave management of two-stage picking. In intralogistics, the goods issue process and return storage is often supported by distribution systems (sorters) to simplify sorting in the second stage.

1st stage of two-stage picking

In the first stage of two-stage picking, the picker collects as many items (goods) as possible from a storage compartment in the storage zone. This saves walking distances through several picking zones (optimization of travel times). The picker places the articles in one or more boxes (however, it is not a Multi-Order-Picking).

The decisive factor here is that the picker counts the correct number of items when picking.

2nd stage of two-stage picking

Once the items have been removed from the warehouse, the order picker transports the boxes to a distribution station for sorting. Only there does the order-oriented sorting to the individual customer orders take place. Each item is scanned and sorted with the help of a distribution system.

The picking process is only completed after the two-stage sorting.

Conclusion

1. Stage:
   Two-stage picking is very suitable for large total quantities of orders. The advantage here is that the picker can remove many items from a storage compartment at the same time. A large order is split up. This saves the picker walking distances. The disadvantage compared to single-stage picking is that the picker may have to count large quantities from a storage compartment, although the potential error here is not very critical.
   
2. Stage:
   In the second stage, the items are assigned to the orders using a distribution system. To do this, each item is scanned and assigned to the appropriate order.

Two-stage picking is very effective, but requires complex technical support and a large total quantity of customer orders for each individual order. This is where the process differs significantly from single-stage picking. Picking can also be carried out by untrained personnel.

The supporting systems

Two-stage picking cannot be realized without the support of picking systems. Various systems are used here for support, such as: Pick-to-Light, Voice Picking, Pick-by-Point^®, Pick-by-Frame^®, etc. are used for support. 

Further details can be found in the following articles:
Pick-to-Light - order picking with compartment displays
Voice Picking - voice-guided order picking
Pick-by-Point - the simple order picking method with light
Pick-by-Frame - the innovation for Multi-Order-Picking

Related topics

Pick time, partial orders, storage location, dead time, picking time, base time, picking performance, order throughput times, distribution time, compilation, throughput times.