LiCON's twin-spindle machine offers an economical solution for small batch jobs

The Twin-Spindle machine with i³ was developed over several years with the initial project between LiCON and Bosch Rexroth successfully implemented in Bosch Rexroth's Lohr, Germany, headquarters as early as 2021. A twin-spindle, 5-axis double trunnion CNC machine was used for this project. 

The main requirement in the machine production of hydraulic valve housings is the accuracy of the control valve bore. To achieve this, the LiCON i³-technology corrects both motor spindles independently, keeping the high spindle stiffness in all three axes (X, Y and Z). Temperature sensors in connection with the corresponding algorithms reduce the influence on the positioning accuracy of the motor spindles during the machining process and lead to fast start-up times. The LiFLEX system also scored points in terms of flexibility: Over a hundred different hydraulic valve variants, each with four workpieces per clamping, are machined on the system.

The compact design of the twin-spindle machine reduced the space requirement while increasing output by 20 to 25 percent compared to the previous solution, the company said. In addition, setup times were minimized, and tool life was increased. 

“The LiCON team responded quickly and easily to change requests at short notice during the project. This meant that adjustments and additions could be implemented together quickly,” said Christof Janker, planner at Bosch Rexroth. “Even during the ramp-up phase, the LiCON service provided excellent support during commissioning,” adds Stefan Thesen, internal overall project manager from the Technical Functions and Investment Planning department at Bosch Rexroth. Customers receive reliable support from their personal project manager and from the service hotline, which is available 24/7.

“Comprehensive customer support is LiCON's top priority,” explained Jochen Hummel, the project manager responsible for Bosch Rexroth.

In addition to the machining center itself, the integration of the pilot cell, consisting of the LiCON machine and the Rexroth automation solution, into the i4.0 system was an important part of the project. Automation and data collection play a central role in the future of both companies. An important step in this direction has been taken with the intelligent networking of machines and processes using information and communication technology.

Evolving technology
Constructive exchange between the two companies then led to a follow-up project with two further manufacturing cells in 2024. This time, the latest LiFLEX II 776 i3 PC B2 with even faster tool changing, minimized non-productive times, and increased dynamics is used. Together with the process optimization, the cycle was further reduced by about 25 seconds (10%) per component. The LiCON ECO Plus mode and the CytroPac hydraulic power unit developed by Rexroth are also part of the machines.

In both machines, LiCON once again relies on hydraulic valves from Bosch Rexroth, which in turn are manufactured on LiCON machining centers. These valves are characterized by their high reliability. The additionally used proportional valves ensure the final polish of the component quality through their finely adjustable pressure via the respective machining program.