DMG's CTX Universal Lathe To Improve Turning Capability At Peter Brotherhood

Chatham, MA - A bottleneck created when turning a range of power generation components at the UK's only steam turbine manufacturer, Peterborough-based Peter Brotherhood, will be eased by the installation of a Gildemeister CTX 620 V4 Linear universal mill/turn centre by DMG (UK) of Luton. The £210,000 machine investment will not only eliminate secondary operations due to its heavy duty Y-axis turret crossfeed capability, but will also reduce extensive expenditure on subcontract working.

Although Peter Brotherhood already employs a turning centre to produce land-based turbine and gas compressor parts, features such as keyways have to be machined as an additional operation. Furthermore, despite running its existing machine continuously across three shifts, such is the demand, that the company still has to outsource components to subcontract suppliers.

Said Dave Head Production Manager: "We looked at a number of CNC lathes that we thought would solve our capacity problem, but the CTX 620 V4 Linear from DMG stood out because of its specification, capacity and price. With a swing of 800 mm and Y-axis crossfeed of + 70 mm we could easily see it would accommodate our work and therefore negate the need for secondary operations. The driven tool unit on the CTX is also between 3 and 4 times more powerful than our existing lathe, so it will easily produce the type of features we have to mill."

The current lathe has some 11,000 component programs on file, giving an indication of the scale of turned part requirements at Peter Brotherhood. The company has over 140 years' experience in supplying customers in energy related industries in more than 100 countries around the world with turbines between 1 MW and 40 MW.

The Gildemeister CTX 620 V4 Linear features a 2,100 mm bed and a Fanuc 160i control. It has a 43 kW direct drive spindle delivering 2,500 revs/min and 2,200 Nm of torque. Idle times are reduced to a minimum because of the high dynamics of the linear drives that enables rapid traverse rates up to 60 m/min to be reached with an acceleration of 1.5 g in the Z-axis. Preloaded precision guides combined with direct measuring systems guarantee high accuracy at rapid metal removal rates.

The turbine and compressor parts due to be turned on the CTX have a tolerance requirement of 0.025 mm. Most of the components, including valve covers, gear shafts and valve cages, are machined out of hard steels demanding a turning platform with high levels of rigidity and significant levels of power.

SOURCE: Gildemeister