Walter Maschinenbau is a manufacturer of grinding, eroding and CNC measuring machines for the production and resharpening of metal, wood and PCD tools. Since 1996, the South Moravian town of Kuřim near Brno has also been one of the production sites of the machine manufacturer, which is part of the United Grinding Group, and has been continuously expanded since then. Following the expansion of mechanical precision production in 2014 with new machining centers and automated pallet loading, Walter recently equipped an existing assembly hall with modern production technology in a construction period of just three months. Tool grinding machines from the Helitronic model series are now produced here highly efficiently in flow production on a new assembly line.

Assembly line pulls platforms along

Intralogistics specialist Losyco installed the conveyor logistics system ready for operation in just eight days. For this purpose, the assembly line was equipped with two Loxrail 25 rail tracks for loads of up to 15 tons over a good 80 meters. Thanks to the underfloor installation of the entire conveyor structure, the production line could be integrated into the hall flush with the floor - without any obstructive steps or gaps. A special drive concept with a particularly low overall height was developed in order to install the transport system below the assembly line in the hall floor. The assembly platforms are moved over the entire distance by a rod hoist installed underneath. As a result, they glide along with the assembly line at a barely noticeable speed like a flowing carpet. To drive the continuous underfloor construction, a chain conveyor is used at the end of the assembly line, which moves the heavy-duty platforms along a defined length. The drive is then retracted by one station and re-coupled. This ensures unhindered, flush-to-floor flow production across the entire line. The assembly teams can carry out the production steps directly from the assembly line. After quality control and functional tests, the finished machine is transported directly to the dispatch hall.

Walter Wysshus Engineering from Switzerland was entrusted with the project management for setting up the new production line. Its core competencies include consulting, management and implementation of lean manufacturing structures, including the selection and procurement of suitable automation and production technology. In Kuřim, the challenges lay in the tight schedule and the timely coordination of all trades.

Particularly stable foundation

The installation of the hall foundation, which was reinforced in some areas with a depth of four meters for particularly high loads, proved to be structurally challenging. Particularly in the plant section for continuous machine acceptance, the foundation must be vibration-resistant so that the grinding tests and measurements carried out on the machines during the production flow are not impaired by vibrations. In order to carry out the quality tests with the same precision as in a stationary assembly line, more than 100 tons of steel were used for stabilization in these areas. A device integrated into the assembly line lifts the machines out of the rail track to create optimum test conditions for continuous grinding. The interfaces show how easy it is to integrate other systems and how accurately the conveyor system works. The precise transfer of the machines to the lifting device was particularly crucial.

Variable underfloor conveyor technology

The Bielefeld-based company Losyco has customized the Loxrail system and manufactured it according to individual project requirements. The manufacturer can adapt both the rail layout and the desired drive technology through to the installation to the respective customer-specific requirements. As a low-maintenance, energy- and cost-efficient alternative to conventional conveyor systems, Loxrail is available in versions with guide shafts of 25 and 40 millimetres in diameter. For both variants, the manufacturer offers transport carriages with corresponding wheel sets as single or double rollers to accommodate loads from 16 to 100 kilonewtons. Thanks to the low-friction running profile of the rollers, even workpieces weighing several tons can be transported smoothly, safely and accurately by hand.

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