Low-wear rol e-chains® for loading gantries in the automotive industry

• What was needed: profile rol e-chain® P4.32 with autoglide® system and aluminum guide troughs, supplied as a pre-assembled readychain® system
• Requirements: high dynamics at travel speeds of 6m/s and accelerations of 6m/s²; wear resistance; high availability; noise minimization
• Industry: automotive industry, machine tools
• Success for the customer: The rol e-chains easily cope with the high dynamics of the system in continuous operation; the roller system is wear-resistant, reliable, smooth-running and requires 57% less drive power than gliding chains; the pre-assembled readychain system minimizes installation time and costs.

The product range of GROB-Werke GmbH & Co. KG includes flexible manufacturing systems for the automotive industry. This includes machining centers, special machines and their automation.

The company has developed a new linear gantry, also called a translator, which was presented with great success at EMO. The new linear gantry is much more compact and smaller than the company's previous solutions. The height of the X-beam above the hall floor is now just under 3.20 m. A new development in this system is the vertical suspension of the skate wheel, which carries a load of up to 80 kg and the loading arm on large skate wheels below the X-beam. The already proven technology of the loading arm in parallel kinematics has also been further improved. The gripper can be supplemented by a pivot axis in the A or C direction. By reducing the moving masses, significantly higher travel speeds and acceleration values are achieved. With a travel length of up to 40m, the speed is 6 m/s, the acceleration 6 m/s2. Speed and acceleration were twice as fast as in the previous model. The dynamics of the linear gantry, which have been significantly improved in this way, enable the loading of linked single and double spindle machines with a single gripper.

A complete production line consists of the linear gantry on one end, and single and two-spindle machining centers for the workpieces on the other. Due to the high dynamics of the gantry, questions quickly arose for those responsible regarding the appropriate energy supply. In addition to other requirements such as high wear resistance and long service life, it was necessary for reasons of occupational safety that the sum of all noises is relatively low at the same time.

During the tests in the preliminary stages, magnetic chains and plastic e-chains were pitted against each other. The decision was clear: internal investigations showed, amongst other things, that magnetic chains neither met the requirements for quiet operation nor permanently withstood the high speeds. The linear gantries usually run six days a week in three-shift operation; machine or system downtime must not occur.

The special design of the rollers and chain links enables particularly quiet operation. The chain is also suitable for high travel speeds, long travels and high fill weights. The staggered rolling of the upper and lower runs further increases the service life of the chain. It is also particularly abrasion resistant. The rol e-chain also achieves exceptionally quiet and vibration-free operation. In addition, there is a silencer profile in the trough that further minimizes noise generation.
Compared to gliding friction, rolling friction is 75% lower. The resulting reduction of up to 57% in drive power means more energy-efficient work processes.

The energy supply system was delivered as a pre-assembled, ready-to-connect readychain system and can be easily installed via "plug and play".
But polymer energy supply systems are also used in the horizontal slide changer in the linear gantry, which replaces the pivot changer during loading and unloading. They ensure the necessary machine and system availability that GROB-Werke guarantees its customers all over the world.