In June 2010 the KNAPP AG subsidiary, KNAPP Systemintegration GmbH, landed the order for designing an automated crate transport and washing system as well as the job as general contractor to deliver and install the crate transport system.
The logistics along the entire supply chain had to be completely converted to the REWE Group’s own crates. Up to now, some processing was carried out with supplier containers. In the spring of 2011 the conversion to reusable, collapsible crates was completed in time for the completion of the crate transport and washing system.
The goal of the project was to be able to remove sticky labels, dirt and leftover food from the collapsible crates before being returned to circulation to be made available to grocery producers again.
The food retail solution
The collapsible crates returned from the stores of BILLA, MERKUR, PENNY, BIPA and ADEG are automatically depalletized and destacked in the Inzersdorf warehouse.
Before the crates are cleaned in a special environment-friendly and energy-saving procedure, innovative machines automatically fold open the crates. Once the crates are dried, they are automatically collapsed. The different types of crates are then sorted with a high-performance sorter.
Clean crates of a single type are then stacked, palletized and secured for transport before they are placed in interim storage.
Unsorted empty crates arrive either on pallets or in roll containers. The pallets are transported on a pallet conveyor system to to automatic depalletization area. Alternatively, roll containers or pallets can also be manually unloaded to a line feeding into the system.
The stacks of crates generated in depalletizing are destacked by machine and separated to two independent lines. A special construction allows the machine to process both folded and open containers.
Crate opener with articulated arm robot
One of the solution’s innovations is the automatic erection of folding crates. Instead of conventional erectors comprising a multitude of mechanical components, joints and pneumatic components, this new development involves the use of an articulated arm robot. All moving components are housed for safety and dirt resistance and the robot guarantees low maintenance operation, even under high demands.
Crate washing system
Crate transport, turning, washing and drying
The opened crates are transported to the washing system on a conveyor that can also handle accumulation. A C-type turning device turns the crates over before they enter the washing system. This also ensures that any dirt falls out of the crate onto the waste conveyor.
The effective cleaning in the washing system is determined by the temperature of the wash water, soaking and the choice of cleaning agents.
Two advantages are provided by a spiral wash machine: Energy consumption is significantly reduced by using less water. The containers are effectively soaked because of the time spent on the conveyor in the machine, and space is also saved. A tunnel dryer with several stages of ventilators is located downstream of the crate washing machine. The crates are finally directed to the servo-driven crate collapsing unit where they are folded up again.
Three types of crates are processed in the warehouse. To provide suppliers with pallets with only one type of crate, the crates must first be sorted by type. The crated are transported to one of three stackers, depending on type, where the foldable crates are stacked up to two metres in height. When four stacks of crates are available, the stacks are moved to the palletizer. A transfer plate moves the crate stack to the pallet. Because of the weight of the pallet, it is essential to secure the finished pallet with a strapping machine.
For damaged or non-stackable crates, the concept includes a separate loop for manual processing.
A transfer shuttle moves the pallets to the buffer lane reserved for that type of crate. Up to five pallets can be buffered on this gravity conveyor. A warehouse vehicle picks up the pallets for transfer to a block storage area.
For the design of the system, REWE International AG and KNAPP laid special focus on dynamic energy management. This feature of KiSoft Reusables Management Solutions (KiSoft RMS) ensures the lowest-possible energy consumption throughout the entire lifetime of the system. Workload-dependant control strategies, redundant line infeeds and start-on-demand all contribute to lowering the energy consumption over the long run and ensure that the use of parts subject to wear is held as low as possible.
About REWE International AG
REWE International AG employs approximately 74,600 people both at home and abroad and is one of the largest employers in Austria with about 39,400 employees.
Around 3,600 branch stores are under the REWE International AG umbrella (status: end of 2011). The business headquarters are in Wiener Neudorf. The Group is represented on the domestic market with the companies BILLA, MERKUR, PENNY, BIPA, and ADEG, as well as numerous store brands such as Ja! Natürlich, CHEF Menü, clever, Quality First, Wegenstein and MY.
In addition, REWE International AG operates in the supermarket segments of Italy and six other central and eastern European countries: Bulgaria, Croatia, Romania, Slovakia, the Czech Republic and the Ukraine.
Using reusable folding crates saves 1.5 million truck kilometres, which translates into 1.4 million kilograms of CO2 emissions annually for REWE International AG. For return transport without goods, these crates need eight times less space than conventional crates, thus significantly reducing the traffic volume on Austrian streets.