Twin-spindle honing machines double productivity

Edited by the Engineeringtalk editorial team Feb 2, 2001

Apperley Honing has developed a twin-spindle honing machine that the company says will dramatically increase productivity in the precision honing market

Apperley Honing, the UK's leading independent contract honing specialist has developed a twin-spindle honing machine that will dramatically increase productivity in the precision honing market.

The new machines, specially designed for polishing the insides of stainless steel tubes to a surface finish of 0.15�m Ra, allow the simultaneous honing of two components rather than just one, thus halving honing time for customers.

From March the machines will be available for sale internationally and for subcontract honing at Apperley's Cheltenham plant.

Charles Sanders, Managing Director, said: "As honing is one of the final machining processes in the production schedule, one of the problems honing companies face is that they invariably receive their raw product later than time-tabled due to the accumulation of delays from preceding production processes.

Halving honing time will therefore be considerably beneficial to the overall timing of such projects." In addition to the productivity benefits of the twin-spindle the company has also reduced set-up time by adding a docking feeder, and incorporating a pivoting drainage cradle to help with the expulsion of honing oil at the end of the process - once again speeding up operations.

The tapered docking feeder helps automate set-up by guiding the honing heads and drive shafts to easily mate with the tubes to be polished.

Without the docking feeder manually aligning the honing heads with the product would be considerably more time consuming.

The first machine in the twin-spindle range is the 17 metre long 'J8', with a 7-metre stroke, which on each operation, can accommodate two 6-metre random lengths, within the industry core diameter range of 50 to 120mm.

Whilst designed and developed for machining thin-wall stainless steel for the semiconductor market, the machine is equally at home with traditional carbon steel and aluminium applications.

The productivity improvements achieved with the twin-spindle are just the beginning of honing improvements.

Sanders explained: "Having developed the twin-spindle we're now looking at triple- or quadruple-spindle machines as long as the appropriate quality thresholds are achievable.

However, some of the advantages achieved with the twin-spindle will also dictate improvements to existing single-spindle machines.

For instance, whilst the docking feeder and drainage cradle were specifically developed for the twin-spindle, set-up and removal times will be reduced by adding them to single-spindle applications.

By reducing the manual handling involved this will also improve safety." The twin-spindle machines are expected to yield greatest benefits to the hi-tech markets, which require extremely high quality finishes on stainless steel tubes for the transportation of specialist gases and fluids.

They make use of Apperley's Contourhoning process, which employs conformable honing stones to adapt to the oval internal diameters of the tubes to be honed.

This allows a high level of precision polishing without compromising the wall thickness of the tube - which would be inevitable if rigid honing stones were used.