Grob unveils new HMC series

As with Grob’s 5-axis universal machining centres, the 4-axis models feature a compact design offering high levels of productivity and optimised stability. In addition to being ideally suited for work in the automotive industry, Grob is also targeting other high tech sectors such as bus and truck manufacturing, rail, agricultural and construction machinery.

The company reports the new machines’ standout features include a high loading weight and the high thrust and acceleration capabilities of the main axes. To reduce the weight of the structural components and increase stability at the same time, the machine series has been designed with the aid of numerical methods such as topology optimisation and FEM simulations.

The machines incorporate a moving column on a rigid machine bed with three fixed points. The rotary axis is powered by a dynamic torque motor and the linear axes via ballscrew drives. On the G640 and G840 models, the workspace can be expanded to a larger height, allowing the use of taller clamping units.

In addition to the 500mm, 630mm and 800mm pallet variants, the three design sizes – G440, G640 and G840 – provide a comprehensive array of available spindle sizes with small and large interfaces for HSK, SK, CAT, BT and Big-Plus.

The spindles, designed and manufactured by Grob, are versatile, excelling at series production, smaller batch sizes and one-offs to high levels of accuracy. A range of automation technologies are available for the machines, and via its Centre of Excellence in Mindelheim, Germany, the company uses 3D planning and process simulation techniques to replicate real-world machining environments.

Potential implementation requests range from a pallet changer with clamping units and sophisticated part clamping technologies provided as standard, all the way up to Grob-developed robot-assisted part and pallet handling systems. In terms of part clamping, Grob designs and manufactures its own systems.

Tool magazines are installed next to the machine as separate, independent modules, and can be easily replaced if customer needs change. Similarly, magazine capacities can scale to meet specific customer requirements. Large variants, holding 450 tools (HSK-A100) are available and can be integrated as part of a manufacturing cell.

The three models in the new 4-axis range offer different capacities: the G440 has working travels of 800 x 800 x 800mm (XYZ) with maximum speeds of 70, 60, 60m/minute (XYZ). Table diameter is 563mm and pallet size is 500 x 500mm (500 x 630).

The G640 occupies the middle ground. It has working travels of 1,050 x 800 x 1,050mm with maximum speeds of 70, 60, 60m/minute. On this model, the table diameter and pallet size rises to 770mm and 630 x 630mm (630 x 800) respectively.

Completing the line-up is the larger G840. This machine features working travels of 1,400 x 1,200 x 1,400mm with maximum speeds of 50, 50, 50mm. Pallet sizes reach an impressive 800 x 800mm (800 x 1,000) and the table diameter is 848mm.

The new series of 4-axis HMCs were exhibited at Grob’s recent ‘Keeping up with the times’ five-day virtual open house in March which also showcased the company’s solutions in the fields of electromobility, Industry 4.0, service and human resources management.

Encouraged by a similar successful event which took place in Autumn last year, the virtual open house enabled customers to interact with Grob engineers and experts across a range of topics and technologies.

Grob www.grobgroup.com