Hella, the automotive lighting and electronics supplier, has centralised its logistics operations at one of its production sites at Recklinghausen in north west Germany. Hella manufactures lighting and electronic components, sensors, actuators, ‘x-by-wire’ systems as well as optical and acoustic signal systems at Recklinghausen. Production areas were supplied with components in a decentralised manner and this was mirrored in the distribution activity, which involved several decentralised locations.
The logistics centre, planned by Miebach and implemented by TGW, is operated by Lila Logistik. It comprises several different storage areas. The materials and items that populate these storage areas are classified by their usage or velocity as either A, B or C items – with ‘A’ being the fast moving items.
All ‘A’ items are stored in a traditional pallet warehouse served by forklift trucks. These items are delivered and stored on pallets and on request are transported to the different production areas via an in-floor conveyor system.
‘B’ and ‘C’ items are stored in an automated small-parts warehouse. Four storage aisles each 45m long and 9m high are equipped with TGW’s Mustang high-performance automated storage and retrieval machines.
The four aisles accommodate 27,000 trays, which act as storage shelves for the stock items that are received either in cartons or tote bins of various sizes, shapes and weights. The tray provides a common load footprint and characteristics for the materials handling equipment to reduce the risk and cost associated with handling a large variety of items with variable characteristics.
The Mustang storage and retrieval machines retrieve up to 600 trays per hour from the warehouse to supply the items and material to the production workstations and distribution operations.
The automated warehouse is located to one side of the logistics centre and is connected to the workstation positions via an automated conveyor system provided by TGW.
Two continuous elevator or vertical conveyors, each delivering up to 800 trays per hour, connect this conveyor level with the working areas on the ground floor.
The logistics centre contains 13 multi-functional workstations. Each workstation is identical in its design but can be used for different functions, which are defined and allocated in the material flow control system. These functions can be changed at any time providing maximum flexibility to the operation.
Currently five workstations are used as picking stations for production supply, six are available for goods issue, one workplace is reserved for returns and one as a clearing station. The items picked for production are delivered to the production areas on trolleys and transported via the in-floor conveyor to the required location within the facility.
A conveyor loop links these 13 workplaces together and connects them to the automated small-parts warehouse. This loop approach is an important design feature as it allows the trays containing the items to be sequenced to the workstations. The loop uncouples the TGW automated storage and retrieval machine activity from the sequencing operation, which allows the machines to operate in the most efficient way. The multi-purpose loop is also used to deliver stacks of empty trays to and from the automated warehouse and the operation.
The material flow control of the storage and conveyor system has a direct interface to a SAP-WM module and manages all material movement and flow of goods throughout the logistics centre. Electrostatic discharge (ESD) protection was a priority for Hella and played an important role in the design, specification and operation of the Recklinghausen facility.
To meet the site’s ESD requirement, belt conveyors, for example, were supplied with conveyor belts made of conductive material and steel slide plates were provided.