Tube Bending - Automation

The last few years have seen some major innovations in the technology of tube and pipe manipulation machinery. The earlier introduction of CNC controlled machines delivered important advantages in the form of shorter set-up times, greater flexibility, increased productivity and repeatable quality but now some of the leading manufacturers in the industry have broken new ground with machines that are not just better but which improve the entire tube manipulation process.

BLM, Europe's leading innovators in tube processing, has been at the forefront of these advances. It has developed machines that combine the various manipulating processes so that a `finished' bent and end-formed component can be produced either on a single automatic machine or in a cell with simultaneous operations. The aim is to maximise automated handling and output and minimise labour involvement.

One such machine is the BLM Dynamo 5-axis tube bending machine. This incorporates a unique load and off-load facility that can dramatically increase productivity. The Dynamo automatically loads the next straight tube at the same time, as the finished tube is being off-loaded, cancelling completely any idle time. The loader and bender can also readily accept pre-endformed tube lengths so that a finished component can be produced ready for assembly or packing.

BLM Dynamo 5-axis tube bending machine

BLM continues to enhance the capabilities of the Dynamo. The company now offers a variant that has been designed specifically for manipulating non-ferrous tubes up to 22mm diameter, making it ideal for the automotive air-conditioning and domestic boiler industry. Another new option is a fully programmable hydraulic pressure die, which is set via the CNC control. This eliminates lengthy manual set-up times and greatly improves bend quality, ovality, wall thickness loss and component consistency.

Endforming machines

Tube endforming machines also play a major role within BLM's range. The latest developments in this field are the AST range of CNC and semi-automatic multi-station tube endformers.

The smallest of these is the BLM AST 25N, which has a capacity of 30mm diameter and offers either 4 ram forming stations or 3 ram forming plus 1 rotary station for operations such as machining, chamfering, facing and rolling. The largest of the family is the BLM AST 122NC CNC endformer. With a capacity of 102mm diameter, this machine offers full flexibility with 6 ram or rotary stations.

Multi-station endforming machines allow even the most complex of endforms to be completed in a single cycle. By using several punches, the material does not have to be moved so much at each stage, allowing much closer tolerances to be achieved and repeated.

All BLM endformers can be fitted with automated handling systems including loaders, bowl feeders, robots etc.

Cell Automation

Some of BLM's customers have taken the automation route to its logical conclusion by combining the Dynamo into a cell formation that can accept coiled material, de-coil, straighten, endform at one end and cut to length in a complete swarfless operation - all on a single BLM Process machine! Switching to coil-supplied material can result in savings of up to 30 per cent in material alone as well as eliminating secondary operations such as de-burring and washing.

By linking the BLM Process, BLM Dynamo and BLM AST machines within a cell with automated load and unload facilities, phenomenal output rates can be achieved. Toolspec Manufacturing, for example, has set up such a cell to produce automotive heater feed pipes for Valeo. Productivity has increased by 400 per cent. Toolspec Managing Director, Dick Corking says, "Material wastage is virtually eliminated and the whole cell requires only one operator to maintain it." An even further degree of automation can be achieved by using robots and conveyor systems to transfer components between machines in the cell.

Planet

Another alternative when working from coil is the BLM Planet, a coil-fed planetary bending machine fitted with an in-line endforming unit and swarfless cut-off device. The Planet can produce complete components in a single operation in a fully automatic process with minimal operator supervision.

The first operation on the Planet is to de-coil and straighten the tube, which is then endformed. The component can then be bent using either conventional draw bending or compression bending, depending on the complexity of the form. Finally the Planet cuts off the finished component with its swarfless cut-off attachment.

Swing

With some bent tubular configurations it is not always possible to bend on a fixed head rotation i.e. left or right hand, because the component may collide with the machine. The usual solution is to use two machines with opposite bend head rotations. BLM's answer has been to design a machine that can bend both left and right-hand bends in the same cycle on the same tube.

BLM Swing Tube bending Machine

The BLM Swing Tube bending Machine combines two bend heads on one machine, which can be rotated through 180 degrees to select the required bend head. Each bend head can also accept up to four sets of tooling for multi-radius components or to combine conventional draw bending with variable radius bending that allows for curves and sweeps to be generated within the component. With this function and flexibility on one machine, it has allowed for designers to come up with components and products never previously possible on conventional bending machines.

Complex tubular frames that used to require two or three machine set-ups can now be completed in one pass, eliminating secondary bending operations, handling between machines and, in some cases, welding operations.

Laser cutting and Production Sawing

BLM's sister company within the BLM Group, Adige, complements the tube bending machines with a range of advanced tube cutting and sawing systems. With the Adige Lasertube LT652, virtually any profile can be cut onto the end of a tube or into the tube along its length. Multiple machining operations, including drilling, sawing, milling, punching, pressing and de-burring, which traditionally require several conventional machine tools and consecutive processes, can be carried out automatically and in a single cycle on a Lasertube.

Adige Lasertube LT652

The Adige CM 502 automatic sawing machine has a comparable versatility, with features that permit secondary machining operations to be carried out on the ends of tubes on the sawing machine itself.

For further product information contact Paul Lake or Jon Curtis, Tel: 01525 402555

BLM-Adige (UK) Ltd
Attn: Jon Curtis
Tel: 01525 402555
Fax: 01525 402312
WWW. http://www.blmgroup.com/
Email.