Extendable quill for deep internal features

A 150 mm diameter quill that extends up to 750 mm from the Heckert HEC 1800 machining centre’s Z-axis spindle enables the use of ‘conventional’ rigid tooling for deep internal machining tasks without fear of compromising the accuracy or quality of workpiece finishes, says Starrag UK.

The extendable spindle is just one of the technology options on the multi-axis HEC 1800 which, with its 1.8 x 1.25 m table capable of accommodating 13-tonne workpieces up to 2700 mm tall, is the largest in Heckert’s HEC range of four-/five-axis horizontal machining centres. In fact, the quill option is available on machines from 800 mm table size upwards.

As well as several standard horizontal spindle options, a range of horizontal and vertical four- and five-axis heads, for example, can also be specified to suit user needs, as well as chain or tower tool storage for up to 450 tools. In addition, a 400 rpm NC rotary table is an option for in-process turning on the larger machines.

The Heckert HEC 1800 has X, Y and Z-axis travel of 3400 x 2800 x 2335 mm, while the 84 kW spindle produces up to 12,500 rpm and 1500 Nm torque.

One of eight Starrag machines installed progressively since 2003 at the University of Sheffield’s Advanced Manufacturing Research Centre (AMRC) and at sister centre Nuclear AMRC by Starrag as part of its membership of both facilities, a Heckert HEC 1800 P150 is available at the Nuclear AMRC to help UK manufacturers optimise their machining.

For further information
www.starrag.com

Boxing clever with double-column machines

The Engineering Technology Group (ETG) has released its Vulcan series of double-column machining centres for large components. Vulcan double-column machining centres allow for the production of parts up to 10 m in length, and are available in box-way or linear configuration.

Box-way models come with a multitude of variants that include the DC 16/20B series and the 23/26B. Within these two variants are several dimensional alternatives. The smallest model in the new 16/20B line-up is the DC2216/20B double-column machining centre. In terms of specification, the DC 16/20B series has an X axis of 2.2 to 4.2 m, a Z axis of 800 to 1000 mm and a Y axis of 1.6 to 2 m depending upon the variant selected. The more compact of the new line-up, the DC2216/20B, has an X axis of 2.2 m with a distance between the columns of 1.7 m.

DC2216/20B models have a 2 x 1.4 m (1.7 m optional) table dimension with a maximum table load of 8000 kg, providing the end user with a spacious work envelope that offers the capacity for large or heavy components. Spindle motor power ratings include 18.5, 22, 26, 30 and 37 kW, with speeds ranging from 6000 to 20,000 rpm.

Regardless of whether the end user opts for a high-speed or high-torque spindle variant, there is a choice of BT50, ISO50 or CAT50 taper to meet the needs of the customer. Working in tandem with the spindle taper is a tooling carousel that can feature 24, 32, 40 or even 60 tool positions.

For further information
www.engtechgroup.com

Heckert X40 enters Factory of the Future

A Starrag Heckert five-axis horizontal machining centre has joined a series of other multi-axis machines in a Starrag-dedicated machining area at the University of Sheffield’s Advanced Manufacturing Research Centre (AMRC) Factory of the Future. Previously applied to a dedicated machining project in another AMRC building in Rotherham, the Heckert X40 now complements Starrag STC 1250 and Ecospeed machining centres, as well as a multi-axis Bumotec s191 turn-mill/machining centre and an NB251 high-speed blisk machining centre in the Factory of the Future, ready to tackle various machining and manufacturing projects.

Established in 2008, the Factory of the Future houses an array of manufacturing equipment that enables partner companies and project sponsors to develop and trial new technologies and processes. The AMRC works closely with its customers and project sponsors to select the ideal machines and manufacturing technologies required to fulfil each project’s individual demands.

“The X40 will undoubtedly prove just as successful alongside the STC and Ecospeed,” says Phil Kirkland, head of the machining group at the AMRC. “And that will likely include extending its initial project work, which embraced the machining of aluminium housings.”

Kirkland adds: “Our partnership with Starrag has been built over a number of years and this addition to the Factory of the Future portfolio further cements our co-operation; we expect the strengths of the Heckert X40 to be fully utilised. Forthcoming projects for the machine will no doubt illustrate how a wide range of components can be produced effectively and efficiently, while the X40 technology will also enable our operators and engineers to upskill on a continuous basis.”

For further information
www.starrag.com

Collaboration between Chiron and NSK

NSK says that its ball screws with nut cooling are setting new standards in the precision of machine tools with mechanical drive components. Confirmation comes not only from NSK’s own testing, but from machine tests conducted with machining centre manufacturer Chiron Group.

As a result of axial forces, acceleration and speed, the ball screw in a machine tool generates frictional heat that can cause the length of the screw to increase and lead to very slight but often critical positioning inaccuracies that may impair machining quality. To help avert this outcome, many machining centres use ball screws with hollow shafts. Coolant passes through the shaft to remove heat from the system. This method is quite costly however, because rotating screws require a rotary union in addition to the hollow bore.

A new approach is to cool the nut, which means there is no need for an expensive hollow bore and rotary union as cooling takes place directly at the point where heat generates. Another key benefit is that the heat generated in the ball screw no longer dissipates directly in the machine. This thermal decoupling between the machine and ball screw is important because any heat can impair dimensional stability.

NSK engineers designed the nut body so that changes to the ball screw caused by cooling have no negative influence on its performance profile, as confirmed by endurance tests at NSK’s Technology Centre.
Many years of co-operation with Chiron Group have also confirmed these results in practice. The use of NSK ball screws with cooled nuts means that machining centres of the Chiron 16 and 22 series operate with high precision, which not only applies to ease of positioning, but to machining accuracy and surface quality.

For further information
www.nskeurope.com

New horizontal five-axis HMC

Japanese machine tool manufacturer Makino has introduced a new five-axis horizontal machining centre (HMC), which made its debut at the EMO exhibition in Milan last October. Productivity on a five-axis machine is sometimes lower than on a four-axis model, but not with the a800Z, according to sole UK and Ireland agent NCMT.

The jacket-cooled spindles provide the same power as on a Makino a81nx four-axis HMC. In addition, the standard 10,000 rpm BT50 (HSK-A100 optional) spindle takes just 2.7 seconds to reach maximum speed and is rated at 55 kW (25% DC), 27 kW (continuous), while torque is 721 Nm (10% DC), 305 Nm (continuous). An optional 8000 rpm spindle provides uprated power at 75/37 kW and higher torque at 1199/552 Nm.

By raising the rear X-axis guideway above the one at the front, the column travels over a slanted plane. This capability allows the efficient transfer of high cutting forces during heavy-duty machining, and maximises the rigidity of the machine structure. Furthermore, the design reduces the weight of the moving column, minimising jerk during acceleration and deceleration. The machining envelope is defined by axis travels of 1,280 × 1,200 × 1,325 mm, actuation being by cooled, large-diameter ballscrews.

Productivity and short idle times are ensured by up to 50 m/min cutting feed rate and 60 m/min rapids. Maximum weight of the fixtured workpiece on the 630 x 630 mm pallet is 1 tonne, excluding the weight of the pallet.

Makino’s a800Z has a high-capacity chip management system. The interior, near-vertical walls in the working area are stainless steel to minimise chip adherence and promote swarf evacuation via three channels in the machine base.

For further information
www.ncmt.co.uk