Flexible machines grind turbine components

Turbine components manufacturing operation has added four flexible, travelling column type grinding systems after an in-depth period of trials and tests

Turbine components manufacturer, Centrax, in Newton Abbot, UK, has recently invested in four high-performance (FGC 2) flexible grinding centres from Hardinge. Centrax placed the order on the Hardinge EMO 2007 stand and finalised the transaction at hardinge’s October 2007 Open House. The machines are scheduled to be installed at the company’s Turbine Components operation facility in Spring 2008.

Selection of the grinding centres had followed an in-depth period of trials and tests organised by Centrax with Hardinge to identify the optimum machine tool solution.

It was based on the following.

* Performance (part accuracy, quality, repeatability).

* Operational efficiencies (increased tool/wheel life, reduced consumable costs, etc).

* Technical and applications availability and accessibility – and price.

R and D and Operations teamleader at Centrax Turbine Components Division, Andy Bould, said : ‘The Hardinge solution was first-class and that’s why we opted for it.

We value Hardinge’s applications support and project management – and that they have taken the time to understand our business and the pressures we face.

The back-up they provide combined with the proven excellence of the FGC 2 machines gave us the confidence to place the four machine tool order’.

* High-precision compressor and turbine aerofoils, discs, shafts and casings – Centrax’s Turbine Components makes high-precision compressor and turbine aerofoils, discs, shafts and casings, including associated hardware such as sub-assemblies and engine modules.

The company is an approved supplier to many of the world’s leading gas turbine engine OEMs and its products are used extensively in civil and military aerospace and industrial gas turbine applications as well as in military auxiliary power units.

* Gas turbines – the company’s Gas Turbine Division manufactures and maintains power generation equipment (from 2.5MW to 6.3MW) for industrial and oil/gas markets.

Set up in 1946, privately-owned Centrax has significant in-house RandD capabilities, and in-depth machine tool applications expertise.

Over the last 8 years the company has invested in six Mark 1 FGC machines (Bridgeport FGC 1) that are still going strong and that can be relied upon to do the work of four or five conventional creep feed grinding machines, said Hardinge to manufacturingtalkmold.wiki.

* FGC 2 Flexible Grinding Centres – Hardinge’s FGC 2 machines are powerful 5-axis travelling column-type vertical grinding centres that have been designed to optimise the creep feed grinding process still further.

The machines provide all the benefits of multi-axis ‘one-hit’ machining – (reduced time spent on job set-ups; reduced workholding and fixturing resources and costs; less operator involvement; increased accuracy due to less work handling; reduced work in progress and greater/faster work throughput) – which, in turn, result in improved delivery times and lower costs per part.

Key performance attributes of the FGC 2 machines include the following.

* Diamond roll (double) dressing capability to cater for extended and/or multiple machining operations – plus the added advantage of being able to dress the grinding wheels in-cycle.

* Automatic wheel change capability (48-position), either 16 x 220mm or 12 x 250mm diameter wheel capacity with 3.5s T-T-T changeover time.

* Powerful 38kW 8,000 rev/min spindle (BT 40 face and taper).

* Improved high-pressure and programmable coolant delivery system that uses twin nozzle technology delivering 90bar at 100L through its wheel cleaning nozzle and 40bar at 120L through its grinding/cooling nozzle.

* Heidenhain iTNC 530 control with specific NGV grinding software enables simultaneous 5-axis machining of complex parts and features (such as nozzle guide vanes and radial dovetails).

In addition to the investments made in Hardinge’s Flexible Grinding Centres – Centrax has a comprehensive range of ‘other’ conventional CNC turning, milling and grinding machines supplemented by EDM, cutter grinder, heat treatment and full CMM capability and has recently made improvements and enhancements to its CAD/CAM capabilities.