A key factor for the successful implementation of the one-piece-flow principle (OPF) in component assembly is the use of flexible handling and positioning systems that allow individual employees to cover as many process steps as possible. At Donaldson, this task is now performed by the mobile lift2move lifting and handling system from Expresso. With OPF, the worker accompanies an assembly through many process steps to the end product - ideally without interruption. For Donaldson, it was important to be able to handle different assembly sizes and designs - so the task was to find a functional and variable assembly system.

Suitable for many process steps

The Donaldson team liked lift2move because a single device can perform various handling tasks such as lifting or turning thanks to the kinematic interaction of the electrically operated lift mast with manual or electromechanical load supports, while also acting as a hand-guided feed system for transport work. At Donaldson, this enables uninterrupted assembly of both the smallest Ultrapac Smart dryers with a height of 50 centimetres and a weight of ten kilograms and the largest models with a height of 190 centimetres and a weight of 80 kilograms - from pre-assembly of the dryer modules through all stages of final assembly to the ready-to-deliver, ready-to-connect product, which is placed in the shipping packaging. One employee always completes the entire production cycle with a lift2move.

When implementing the OPF line, it was important to ensure that there were no idle times or detours. For the design of the Expresso system, this meant that time-consuming set-up work had to be avoided and the fitter had to have free 360-degree access to all assembly points on the dryer at every stage of the process. Ergonomics and physical relief for employees throughout the entire process were also essential.

High flexibility and a special solution

An Expresso model from the mid-range of the overall range was selected, the lift2move 225 with safety trolley and single lift mast with electromotive spindle drive and positioning controller. With a maximum load capacity of 225 kilograms, this was the ideal starting point for the further development of the assembly system for Donaldson, which now focused on the design of the load support. The lift2move is available in four basic models with a single lift mast for payloads of up to 225 kilograms and one model with a double lift mast for loads of up to 400 kilograms. There are also several chassis modules. The application-specific load support on the lift mast was designed as a manually rotatable workpiece clamping system with an adjustment range of almost two meters and an integrated brake to control the rotation function. Even during the test runs, this turntable design with its torsion-resistant support system consisting of two aluminum profile rails, in which various holding elements, clamping devices and clamping jaws can be moved by hand, proved to be the perfect solution for Donaldson's specific OPF assembly.

The turntable clamping system is impressive

A total of four lift2move with turntable clamping system were initially put into service at Donaldson. As required, they enable the secure fixing of constantly changing modules and components from various compressed air dryer series and allow unhindered all-round access to all mounting points. With the Expresso turning mechanism, the fitter can manually place or set the clamped main module of the dryer - usually its housing - in any desired position on the x-axis. The ideal height of the y-axis on the lifting mast, on the other hand, is adjusted by motor. A handy remote control gives him enough freedom of movement to adopt the best viewing position. With the positioning controller, it can move to several programmed stopping points with repeat accuracy. An integrated motor brake ensures smooth, jerk-free lifting and lowering. During all actions of the turntable clamping system, the low-lying stability chassis of the lift2move guarantees the stability of the assembly system as well as its all-round mobility in the z-axis. A height-adjustable push handle and smooth-running castors make it easy to move forward in the process. A three-stage parking brake enables the lift2move to be braked gently and parked safely on the marked assembly bays.

For Donaldson, the use of further assembly devices of this type is conceivable. The decisive factor is that an assembly system now exists that does not restrict the future development of the production line.

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