picking
picking work on the shelf
In short, picking is the assembly of goods and products according to orders from a complete range. Different systems, methods and procedures are used for this. Due to the high time pressure, all processes must - ideally - run smoothly.
Table of contents
definition
Picking means putting together certain partial quantities - articles - from an existing total quantity - assortment. The basis for this are orders. The following order options are conceivable:
- material provision for production
- deliveries to customers
- returns to suppliers
- transfers between different warehouses
- replenishment of sales warehouses
The employee who picks the goods and carries out the order can be called something different.
- picking
- picker
- gripper
challenges
Companies are faced with ever-increasing demands that require smooth order picking. Customers expect fast and correct deliveries. The pressure on companies is high - not least due to the increase in online trade.
- Increasing assortment and greater product variety
- Lower number of items per individual order
- Overall larger order volume
picking systems
Manual picking
- Dynamic picking: goods-to-person systems
- Static picking: person-to-goods systems
Automated picking
picking robots
With this system, picking robots receive data from the warehouse computer. This enables them to drive to the corresponding shelf and then retrieve the item using a gripping system - usually equipped with suction cups. The selected item is then placed in a container that is carried along.
- The gripper is equipped with an image processing system.
- The correct amount to be removed is determined by the weight of the item.
The following data is transmitted to the picking robot:
- storage location via coordinates
- number of pieces
- weight of the item
picking machines
In this system, items are located in shafts that are attached to both sides of a conveyor belt. Each item has its own shaft. For each order, a container labeled according to the order rolls over the conveyor belt. The required item is then ejected from the shaft into the relevant container.
picking process
The methods used for picking vary. The specific use depends on the following factors:
- number of articles
- article quality
- order quantity
- storage strategies
- industry
The goal is to achieve a high pick rate and keep the error rate as low as possible.
pick-by-paper
This variant is the simplest. The picking is done using a paper slip. This contains the following information, which is used for picking:
- storage area
- article number
- Crowd
It is mostly used in traditional warehousing (block storage) in small companies, as no large investments are required and the process is very adaptable to spontaneous expansions. The data is entered into the system later, which means that the material flow is not always clearly visible. In addition, the process is very labor-intensive.
- Prerequisite: Good warehouse knowledge!
Pick-by-MDE
MDE stands for mobile data capture devices. Electronic devices are used for order picking, which either have the information already stored or receive it via WLAN. This process is used in almost all logistics areas.
Mark:
- Operation is via keyboard, display/touchscreen and a scanner
- Order information is displayed on the device
- Direct communication with the warehouse management software
- Avoiding picking errors, saving time
pick-by-terminal
Data transmission in this picking process takes place via radio. The system required for this is permanently attached to an industrial truck . The scanner used records the following information in no time at all:
- article numbers
- serial numbers
- batch numbers
This method is suitable for companies that have to pick bulky or large goods. It also has a low error rate when picking.
Pick-by-Scan
In this picking method, the picker uses a mobile handheld computer to carry out his orders. This contains a 1D or 2D barcode scanner. It provides the following information:
- Article
- Crowd
- parking space
A minimal error rate and the forwarding of order data to an ERP system after completion make this system popular.
Pick-by-RFID
In this picking process, all packaging is provided with a rewritable transponder. It consists of a data storage device and an antenna for transmitting the data.
- Mobile data collection devices with voice input pass the commands on to the picker, who wears a headset.
Pick-by-Point
This picking method works with a laser that is attached to the respective shelf aisle and shows the picker in which compartment the respective item is located.
- Confirmation of article removal via laser sensor
- warning signal in case of incorrect removal
Pick-by-Light
This method involves displays with light signals attached to shelves. The light signals indicate the corresponding shelf and the display shows the number of items to be picked.
- Suitable for warehouses with a high picking speed
Pick-by-Voice
In this proven method, the picker wears headphones with an integrated microphone. In addition, an MDE is attached to the belt, which is connected to the headset and to a host system and a material flow computer. Communication between the picker and the system takes place via voice.
- The picker has both hands free
- Low error rate and very efficient
This process is often used in deep-freeze areas or in the automotive industry.
Pick-by-Vision
During this process, the picker wears data glasses. These replace the system's voice instructions and guide the picker through the order steps. Optical displays show the picker the location and the number of items.
picking methods
Picking orders usually consist of several different items. Several methods are usually used to ensure a smooth, efficient process. Here are three basic methods:
Order-oriented, serial picking
The individual orders are processed one after the other in different warehouse areas.
- A picker passes through all storage zones per order
- There is one picker per order per storage zone
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Order-oriented, parallel picking
Each customer order is divided into sub-orders - according to the storage zones. This means that picking can take place in parallel in the individual storage zones. After each order has been executed, the sub-orders are merged.
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Series-oriented, parallel picking
The incoming orders are grouped into series. Within a series, the orders are then split up into the positions of the individual storage zones.
- An article that appears in several orders can be recorded collectively, saving time.
The individual items are then assigned to their original individual orders.
| Advantages | Disadvantages |
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BUT:
- Shortcut strategies shorten picking routes! Shortcut strategy means that all items that are picked very frequently are stored near the shipping location.
- Route-optimized picking lists! Meaning: Orders whose storage locations are close to each other are summarized on a picking list.
