CNC retrofit rejuvenates ageing milling centre
11 February 2013
When SPX Clyde Union needed extra line boring capacity for the production of a range of centrifugal pump cases, it decided that the optimum route would be to have an ageing horizontal boring and milling centre completely re-engineered and fitted with a new CNC system. The subsequent retrofit has given the machine a new lease of life.
Production control manager Bob Scrivens needed to ensure the continued production of SPX Clyde Union's range of single-, two- and multi-stage, as well as reciprocating pumps, at its manufacturing site in Sheffield. These pumps find their way into a variety of applications, from clean water duties to main reactor feed pumps at nuclear power plants.
Mr Scrivens enlisted the re-engineering and retrofitting services of Huddersfield-based C T Systems (CTS), a company with an established reputation as a specialist in system integration/motion control automation.
Utilising an old Kearns-Richards SF125 horizontal boring and milling centre that was available from another SPX group site, CTS’s Chris Haigh took control of the project. With new hydraulics, lubricant system and electrics, plus the replacement/manufacture of new gears where appropriate and the installation of new ballscrews, this was no trivial project!
Moreover, the machine’s bedway needed regrinding and a new boring stay had to be manufactured; CTS had the part cast and machined it itself. The final task was the integration of the new CNC system - a Heidenhain TNC 320 with new drives and control gear.
“We’ve been retrofitting and integrating Heidenhain control systems for more than 20 years,” says Chris Haigh, “and with SPX Clyde Union Pumps already using a TNC-boring/milling set-up elsewhere on site, it was no surprise that the TNC 320 was selected.” Mr Haigh believes the TNC 320 is an ideal entry-level analogue CNC system for retrofit applications on milling, drilling and boring machines.
Bob Scrivens adds: “It was important for us to maintain standardisation of control technology; the line boring tasks are especially critical and it is essential that our machine operators are completely confident in the CNC technology they use. The TNC 320, of course, provides clear overviews of all information – including program blocks, comments and error messages.” Also important is the CNC’s graphic support during program entry, test run and actual machining. Bob Scrivens again:
“The selectable split-screen display shows both part-program blocks and status display and, as the program progresses, there is instant information on tool position, current program, active cycles and co-ordinate transformations.”
Today, thanks to modern mechanics and electrics - not to mention the Heidenhain TNC 320 CNC - the new-look machine is consistently handling workpieces weighing up to eight tonnes. It is proving an indispensable aid to production and, in Bob Scriven's opinion, a "cost-effective alternative to buying a new machine”.
Contact Details and Archive...