For more than 40 years, Swiss company PL Lehmann has been building compact, high-precision CNC rotary tables. Within a minimum footprint on the work table, starting at just 136 by 311 mm, these products offer not only a wide variety of workpiece clamping options, but maximum use of the machine tool’s working envelope and travels.
Mark Jones, managing director of Leader Chuck International, says: “These CNC rotary tables are designed for the economical production of small to medium-sized workpieces. By minimising the footprint needed to fit the rotary unit on the work table, the machine can be set up and ready to run, whereby typical 3-axis machining operations can be conducted at one end of the work table, with the 4th-axis rotary unit fixed at the other.”
With just four basic sizes of rotary tables extending from 100 to 500 mm diameter, Lehmann covers the performance range required by most machine shops. Rotational speeds up to 210 rpm provide a 90° index in just 0.21 seconds. Furthermore, a feed torque of up to 750 Nm, combined with heavy-duty bearing, allows high spindle loads for aggressive cutting strategies
Manufacturing precision tool holders, KTA Spindle Tooling adds a comprehensive range of hydraulic tool-holding chucks to Leader’s portfolio. With more than three decades’ experience in the design and manufacture of tool holders, and a production capacity of 10,000 holders per month, extensive stock is held at the company’s facility in Germany.
KTA operates to an accredited ISO9001 quality management system, and its products – hydraulic expansion chucks, shrink-fit holders, tapping chucks for synchronised tapping cycles, tapping chucks operating on expansion and compression, ER collet chucks, face-mill holders and Weldon holders – are produced to tight tolerances and balanced to 2.5 g (vibration velocity in mm/s) at 25,000 rpm. Hydraulic chucks are, by design, easy to use and maintain, and with reduction sleeves can be used for drilling, reaming and milling operations. All of these chucks offer guaranteed runout accuracy of less than 5 micron.
Hydraulic chucks provide high accuracy (typically 0.003 mm) and repeatability, with good torque transfer of cutting forces. Such chucks are suitable for mould and die making, as well as the machining of precision automotive and aerospace components. Available mounts include BT, KBT, SK and HSK, CAT, cylindrical shank, VDI shank and ER.
With over 60 years’ experience, Fial produces a range of manual chucks for conventional and CNC lathes and turning centres that are interchangeable with all popular brands. Following the recent partnership agreement between the two companies, full pre- and post-sales support for the Fial range in UK will be provided by Leader Chuck International.
Manufactured in Italy under ISO 9001 accreditation, the chucks are available in 2-, 3-, 4- and 6-jaw formats, with self-centring or independent jaw operations. Chucks from 125 mm diameter up to 630 mm diameter are available ex-stock from Fial’s warehouse, where real-time product tracking controls stock chucks valued at over £1 million. Larger chucks, up to 1,250 mm diameter are available to order on very short lead times. Direct spindle mounts supported include AFA 2 (DIN 55026) American short taper; D1 Camlock (DIN 22029); and Type C stud mount (DIN 55027).
Another Italian company that will use MACH 2020 to launch its partnership with Leader is Tecnologie FRB, which offers live centres and face drivers for turning, grinding and hobbing machines. The company’s face drivers can fit any workpiece holder, ranging from 5 to over 300 mm diameter, from the classic spring-operated system to the most advanced hydraulically operated system.
Manufacturing face drivers for over 50 years, only one thing has never changed: the FRB patented balancing and holding system. Being completely mechanical, it ensures absolute reliability, constant repeatability of results and high holding capacity, reports Leader.
Live centres start with the FRB patented 65, 80 and 85 series featuring axial load distribution, and extend to the latest 2000, 2006 and 2008 series. Today, a wide variety of revolving centres is available equipped with Morse tapers (ranging in size), with standard or special features to suit any requirement.
For the clamping of challenging workpieces, SFT Spannsysteme GmbH, located in Bavaria, offers a range of intelligent multi-purpose clamping solutions for machining operations, including a 5-axis multiple clamping device, as well as the Zentro and Smart vice ranges.
The latest SFT two-in-one 5-axis – or multiple clamping – device has several features of note, including a flexible, modular jaw system with positive-locking jaw connection at 40 kN. A 4-tonne clamping force can be achieved with just 85 Nm of torque.
SFT’s Zentro centric vice is said to be suitable for high-precision manufacturing with internal and external clamping capability. Repeatable accuracy is just 5 micron from the high rigidity, modular jaw system design that offers 30 different jaw designs as standard. An enclosed spindle removes any concerns over swarf ingress.
Convertible from centric to double-centric operation, or for clamping against a fixed jaw and/or double-clamping against a fixed jaw, the SFT Smart vice is designed for small parts, offering up to 15 kN clamping force with jaw widths of 22, 32 and 42 mm.
