WARD CNC-SUPPLIED HARTFORD VMC CUTS COSTS AND IMPROVES PRODUCTION AT MACTAGGART SCOTT
The installation of a Hartford vertical machining centre is MacTaggart, Scott & Co’s latest strategic advance in the company’s non-stop quest for continual improvements across all its operations. And the machine – installed by T W Ward CNC Machinery Ltd. (Ward CNC), the exclusive UK and Ireland agent for Hartford – has certainly not let the company down. It has:
 Cut cycle and lead times on existing work through the introduction of new, single set-up machining strategies
 Enabled components to be produced that were formerly impossible to manufacture on existing machines
 Allowed the use of standard tooling in place of form and special tools, thus reducing production costs further.
Replacing an ageing manual planer mill, the new Hartford Diamond DBC 6340W double-column VMC undertakes a range of “normally straightforward” milling tasks on linear-type components up to five metres long by 1.5 metres high and wide, including equipment for submarine periscopes at the Loanhead (near Edinburgh) site.
Such components fall well within the machine’s X, Y and Z axes envelope of 6,050 mm by 3,400 mm by 700 mm – plus its 1,100 mm W axis. With a 4,000 revs/min geared, 30 kW ISO 50 spindle and 40-tool automatic toolchanger, the Hartford also boasts rapid traverse rates of 12 m/min in X and 16 m/min in Y and Z, plus 3 m/min in W, and has a cutting feed rate of up to 6,000 mm/min.
It handles a variety of workpiece materials, including stainless, super duplex and standard steels, as well as nickel alloy bronze. During the machining processes anything from two per cent up to 40 per cent of original billet is removed.
According to Production Engineering Manager Robert Davidson, in addition to the “obvious enormous time savings” being achieved by the higher operational speed of the Hartford compared to the manual planer mill, further gains are being made by the introduction of new ways in which certain components are now being machined.
“In one instance, instead of the use of form and profile tools, we are using standard carbide tooling to take relatively small cuts then, in the same set-up, milling all the required profiles at higher speeds,” says Mr Davidson. “It all contributes to improved efficiencies in our manufacturing regimes.”
The benefits of MacTaggart Scott’s fresh-thinking approach to existing routines mirrors the company’s ongoing success with at least one other Ward CNC-supplied machine at the long established (since 1898) company that focuses on the naval defence and marine industries.
A large-capacity Soraluce travelling column floor-type CNC milling machine with an extensive 16 metre long bed enabled MacTaggart Scott to bring in-house the machining of extra-long workpieces – a move that in itself justified the machine purchase.
But also, after expert engineering from Ward CNC added a second machine column onto the original machine bed, to give a double-column single-bed duplex configuration, MacTaggart Scott was able to embrace a new era of machining parts simultaneously at ‘both sides’ of the machine bed or, using one column, to machine very long components.
It is, in fact, Ward CNC’s consistent prowess at supporting the Soraluce machine (and others - the company has sourced other machines, particularly horizontal borers, from Ward CNC for a number of years, including two Union BFT 130/7s, a Union BFT 130/5 and a Hyundai-Kia SKT 28LB) that played a major role in the selection of the Hartford VMC.
Mr Davidson again: “When looking for a replacement, we surveyed the market and created a shortlist of three machines. The Hartford won the day, based not only on the machine’s capabilities and cost but, importantly, also because of Ward CNC’s ability to service and support the installation most effectively.”