5-axis machining centres for maximum precision and performance

With the aim of meeting customer requirements in the best possible way, HELLER has expanded the latest generation of the F series, which was launched at EMO 2023 in Hanover with the model F 6000. The HELLER Open House 2024 was the first opportunity for visitors to see the new model F 5000 up close, including its new features and key components such as motor spindles with HSK-A 63 tool interface and space-saving rack-type tool systems. Due to their modular design, the new high-performance 5-axis machining centres can be optimally configured for a wide range of applications, always ensuring maximum precision and performance in the production of small to medium batch sizes.

In the autumn of 2023, HELLER launched the F 6000, the first 5-axis machining centre (MC) from its new, modular F series (XYZ: 1,000 × 1,000 × 1,400 mm). About six months later, another model was introduced: the F 5000 with a work envelope of 800 × 850 × 1,100 mm (X/Y/Z) and a smaller footprint. The F 6000 offers the same pallet size of 630 × 630 mm and maximum clamping load of 2,000 kg, as well as the same traversing speeds and other performance data as the F 5000. That is because key components such as spindles, heads and tables of both new HELLER F machines are based on the same modular system.

Swivel heads with motor spindles ‘made by HELLER’

The highlights of the new generation of 5-axis machining centres, optimised for maximum flexibility and precision, include the fundamentally redesigned swivel heads and integrated motor spindles developed and built by HELLER, which are equipped with an HSK-A  100 tool interface as standard and are now available with an HSK-A 63 interface as an option. The dynamic swivel head with 5^th axis ensures maximum machining performance. Its drive is based on a backlash-free drive concept and delivers impressive precision. Other useful features include an integrated work light and a remaining path indicator as part of the SETUP-Assist function.

HELLER offers a variety of spindles to suit different requirements: the Speed Cutting Unit (SCU) in combination with the HSK-A 100 tool interface reaches speeds of 15,000 rpm. As an alternative, HELLER offers the Dynamic Cutting Unit (DCU) designed for universal use with 400 Nm and 12,000 rpm. Combined with the HSK-A 63 tool interface, they reach speeds of up to 18,000 rpm. The Power Cutting Unit (PCU) with a 146 Nm, 8,000 rpm gear spindle will continue to be available for ultra-heavy machining.

Robust kinematics, high precision

Another key element of the F series is the revised drive concept of the linear axes, with twin ball screw drive in the Z-axis and a significantly reinforced X-axis. Dr Manuel Gerst, Head of Development at the HELLER Group, explains: “With the F 5000 and F 6000, we offer increased dynamics in the linear axes. Additionally, we have further reduced the positional tolerances with the PRO package. The new standard is 5 μm. Tolerances on the rotary B and C axes have also been reduced to 7 arc seconds as standard. Overall, this results in top marks for workpiece accuracy and machining time.”

User-friendly and ergonomic

HELLER’s new F series machines also offer a number of features to ensure high ease of operation. Convenient access to the work area and an LED light built into the head add to the user-friendliness. The new SETUP-Assist actively supports the operator when running in machining processes and helps prevent collisions between machine components and tools.

The new SINUMERIK ONE control generation from Siemens used as standard offers an optimum working environment in combination with the convenient main operating unit in console design with a 24-inch touch screen. Naturally, existing NC programs from HELLER F and C machines equipped with SINUMERIK 840D sl can be transferred directly and effortlessly by the user.

To increase process reliability, the HELLER developers ensured free chip fall below the spindle and effective removal of chips. Steep stainless-steel covers and a wide chip conveyor also contribute to this.

HELLER Head of Development Dr Manuel Gerst. Source: HELLER

New rack-type tool magazines with a particularly slim footprint

The new machine design, especially direct chip evacuation to the rear of the machine, has significantly reduced the footprint of the HELLER F series. As a result, it is only about 3,700 mm wide. Combined with HELLER’s new rack-type tool magazines, both machines are still extremely compact while offering high tool storage capacity. And despite the ample tool space they provide, they are almost two metres slimmer than the previous models. This is particularly useful when it comes to automating multiple machining centres. Four machines can now be placed in a row where previously only three could be installed.

The various expansion stages differ only in length. The rack magazines, designed for HSK-A 100 tools with storage capacities of 200, 260 and 340 tools, are no longer than 7,000 mm. They provide 489 storage positions for HSK-A 63 tools.

The space-saving arrangement of the tools is crucial to the compact dimensions, enabling a high packing density. The integrated preferential storage module significantly reduces tool provisioning times in practical use.

What is more, on selected machine sizes and combined with the HSK-A 100 tool interface, the preferential storage module provides space for tools up to 800 mm in length. Easy manual tool loading is achieved with an integrated rotary station. It allows up to seven HSK-A 100 or nine HSK-A 63 tools to be loaded in parallel to machining. To optimise ergonomics, HELLER has also designed the racks so that tools can be loaded by crane at any time.

HELLER Rack-type tool magazine. Source: HELLER

Full flexibility in use: HELLER motor spindles

The expanded range of spindles is likely to be of particular interest to sectors such as the aerospace industry. In addition to the proven versions with HSK-A 100 tool interface, the F 5000 and F 6000 can now be equipped with motor spindles with HSK-A 63 interface. High speeds of up to 18,000 rpm combined with short run-up times make them ideal for machining light metals – for example, complex, integral components for aircraft, machinery or vehicles.

New tilting heads provide greater flexibility

In terms of kinematics, the range will see a further expansion this year. As an alternative to the swivel kinematics, tilt kinematics will also be available from the autumn. As part of this, the range of machining units will be expanded by four new tilting head variants. In line with the modular concept, HELLER will again use the motor spindle variants developed in-house. In combination with HSK-A 100, they offer torques up to 400 Nm, while the HSK-A 63 versions focus on speeds up to 18,000 rpm.

Compared to swivel heads, tilting heads offer a significant increase in flexibility for 5-axis machining. The tilt kinematics can also be used to machine recesses and undercuts, for example. Head of Development Manuel Gerst explains: “Especially for the production of integral components, which are often required in the aerospace industry, it is very important that the machines used can also machine at a negative angle. Mechanically, this is not possible with swivel heads. We have designed the new tilting heads specifically with these applications in mind. With an HSK-A 63 tool interface and a high-speed spindle, they are predestined for such applications.”

HELLER Swivel head with motor spindle. Source: HELLER

Easy to automate

Like the F 6000, the F 5000 5-axis machining centre is available with automatic pallet changer (APC) as standard. This is also the first level of automation of the machine.

In addition, HELLER will also offer a FLEX version of the machine without the integrated pallet changer. In this version, the F 5000 and F 6000 are approximately one metre shorter. “The FLEX version really comes into its own as part of an integrated system with external automation. Combined with linear and rotary pallet storage solutions, machine utilisation time can be significantly increased, whilst offering greater flexibility in terms of workpiece size and pallet clamping load,” says Manuel Gerst. The advantages of the FLEX version are particularly noticeable on workpieces with long cycle times, as the slightly longer workpiece changeover times compared to the APC version are negligible.

The FLEX version is offered in conjunction with external automation. It is possible to add a HELLER rotary pallet storage (RSP) as well as a standardised linear pallet storage. By the way: automation can also be upgraded on APC versions. And for those who do not wish to integrate an automation system from the outset, HELLER offers the ‘Automation READY’ option. It allows standardised pallet automation systems to be retrofitted quickly and easily.

Complete machining with optimum cutting performance

With an optional Mill/Turn function, F series machines can also be used for combined milling and turning operations. This is made possible by the high-torque DDT (Direct Drive Turning) rotary table, with speeds of up to 700 rpm. In addition to conventional milling and drilling operations, longitudinal or planar machining of external and internal contours is possible, as is the production of a wide variety of undercuts and recesses – all in a single set-up. Even cutting of external and internal threads is possible. This eliminates the need for reclamping on separate turning machines, resulting in improved workpiece accuracy and significantly reduced cycle times, especially for series products.

Wide chip conveyor. Source: HELLER