Robo-Trex makes light work of lights-out milling

The availability of automation aids, such as the Lang Robo-Trex system from Thame Workholding, are allowing forward-thinking businesses to operate milling machines unmanned for extended periods. One such company is Hertford-based subcontractor Qualiturn Products, which operates 24 hours a day, seven days a week, 365 days a year, with only daytime staffing.

The recently installed Lang Robo-Trex robot system at Qualiturn (the first in the UK) feeds a Doosan DNM500 machining centre from two trollies. Each trolley serves as a mobile storage medium for multiple vices that hold workpieces ready to be loaded into the machine. Depending on the part sizes involved, the trollies are able to store up to 42 loaded vices. The Lang Robo-Trex system uses an articulated robot with a handling gripper that is capable of loading and unloading workpieces of up to 12 kg.
“Having previously enjoyed the benefits of other Lang workholding systems supplied by Thame Workholding, we already had great confidence in the quality the products,” says managing director Nick Groom. “After viewing a video of the Lang Robo-Trex automation system in action and recognising the lights-out advantages it would deliver, we calculated our anticipated ROI and decided that the system would be more cost effective than purchasing another CNC machine tool. In fact, the success of the Robo-Trex, which has released the latent productive potential of the machine tool it serves, means that we already have plans to install a second system.”
For further information www.thame-eng.com

Adhesive workholding system for awkward parts

NCMT Fixture Solutions used the recent EMO exhibition in Hanover to demonstrate the advantages of the photo-activated adhesive system, Blue Photon. Intended for the manufacture of workholding systems used on machine tools, NCMT says that Blue Photon is suitable for securing awkwardly shaped parts that require tight-tolerance machining and inspection.

The process involves applying an adhesive that is cured by ultraviolet light via an LED spot-curing system. Next, the adhesive can subsequently be melted and the machined workpiece removed by immersion in hot water or by application of another heat source, which should be at 80°C. Alternatively, the adhesive contact points can be sheared to free the workpiece by rotating the gripper pins in the fixture plate with a spanner.
Use of the technique is predicted to grow rapidly due to its ability to hold components securely with an average shear resistance of 136 kg per gripper point, yet allow cutters all-round access for machining on five sides. Unlike solutions that use magnetic clamping, the Blue Photon system can be used to secure both ferrous and non-ferrous metallic workpieces, as well as ceramics and composites.
Blue Photon can, for example, clamp a turbine blade to enable the fir tree and wedge face on the root, as well as the shroud end features at the tip, to be ground in one-hit. Traditionally, due to clamp interference, multiple operations are required using conventional CNC grinders. The Blue Photon single manufacturing process is not only faster, but eliminates work-in-progress and the risk of introducing inaccuracy due to repeated re-fixturing. Tests have shown that the clamping force produced by the system can easily withstand the requirements of machining.
For further information www.ncmt.co.uk

Collet chuck allows full capacity spindle operation

Available in the UK from Leader Chuck, Lexair’s full-bore, fixed length, self-contained collet chuck allows full capacity spindle operation, due to elimination of the draw-tube. When using the full-bore chuck, spindle capacity is boosted as much as 30% and clamping pressure is unaffected by centrifugal force, regardless of spindle speed. An adjustable grip lightly grasps delicate tubing or clamps tight for deep rough-cutting operations. Intended for bar feeding or slugging, the chuck can be used on main or sub spindles, rotary indexers and machining centre tables.

The chuck’s open/close time is less than half a second and it provides true dead length clamping with no drawback. A mechanical locking action holds the workpiece, even without air pressure, for failsafe operation. The chuck uses air to release the work, rather than secure it, and spring force holds the workpiece while it is being machined. Lexair’s collet chuck has full concentricity adjustment to help maintain accuracy when using Master collets with S-type pads.
Available in seven models with body diameters from 150 to 355 mm, the collet chuck offers bar capacity from 50 to 140 mm. The chuck also features direct spindle mounting for A5, A6, A8 and A11 tooling.
For further information www.leaderchuck.com

Jaws offer centrifugal force and vibration compensation

Schunk says that its new hydraulic compensation jaws set a new benchmark for low-deformation workpiece clamping. According to the company, it is the first time that chuck jaws for compensating the workpiece clamping process have successfully been combined with centrifugal force compensation, vibration-damping characteristics and micron-precision concentricity.

The integrated oil chamber innovation and clamping technology is a central feature of the new hydraulic compensation jaws. Above this are two oscillating clamping elements for clamping rough or finished component workpieces. As the jaws individually adapt to the workpiece, form tolerances in castings, for example, are reliably compensated. Compared with conventional three-point clamping, the number of clamping points is doubled, which lowers workpiece deformation. Obtainable roundness is also increased.
At high speeds, the hydraulic clamping system automatically guarantees centrifugal force compensation, which ensures that the clamping force is always reliably maintained. In order to minimise workpiece deformation, the clamping force can be considerably reduced in comparison with previous solutions without restrictions on process reliability.
For maximum precision on the component, the concentricity can also be adjusted with micron-precision on the chuck jaws. Additionally, the vibration-damping characteristics of the oil chamber system benefit the surface quality of the workpiece, while tool life is increased.
For further information www.schunk.com

Workholding system improves productivity

When Chick Workholding launched its One-Lok clamping system seven years ago as an alternative to the conventional machine vice, the company made available more precise workpiece positioning and a time-saving ratchet mechanism to adjust the position of the moveable jaw quickly. New lightweight versions have now been unveiled, offering users additional benefits. Availability in the UK is through sole agent 1st Machine Tool Accessories.

The latest One-Lok comes in two sizes rather than one, 400 or 500 mm long, offering maximum gripping lengths of 180 and 280 mm respectively. Further improvements include a lowering of the clamp profile from 150 to 134 mm, which allows longer spindle travel in the Z axis and halves the unit’s weight for easier handling. With this in mind, an ergonomic hand grip has also been added at either end.
Sometimes, machinists turn a vice through 90° so that it lies transversely across the machine table. This strategy can bring the part closer to the operator, but has the disadvantage that there is no clearance for the handle. With the new One-Lok, workholding in this orientation has been made easier by using a ratchet handle.
The moveable jaw on One-Lok systems can be adjusted quickly and conveniently, as it can now be slid using one hand rather than two over the QwikSlide ratchets. A few turns of the handle move the jaw in the same direction over the last few millimetres to complete the clamping action. The existing BoltFast interface for the 152mm wide, interchangeable hard and stepped steel jaws and aluminium soft jaws, has been retained. A quarter turn of the locking screw is all that is required to exchange them, promoting productivity when machining small batches of components.
For further information www.1mta.com