Driving things forward

When the need arose to purchase a new gear grinding machine, the company chose a Hofler Helix 400 SK supplied by UK agent Micronz. Solutions reports. 

A public company, quoted on the London Stock Exchange and a constituent of the FTSE tech Mark 100 index, Ricardo's client list includes the many of the world's premier transportation OEMs, supply chain organisations, energy companies, financial institutions and governments.

Since Ricardo was founded nearly a century ago, the company has been renowned for its track record of successful research-led product innovation and development expertise. Ricardo's in-depth technical knowledge and wide experience is particularly apparent in the transportation sectors, ranging from passenger cars and motorcycles to commercial, agricultural and off-highway vehicles, railway locomotive power and marine propulsion systems. Key areas of expertise include: low carbon gasoline, diesel, hybrid and fuel cell powertrain technologies; the latest driveline and transmission systems; control electronics and software development; and vehicle systems integration.

Based in the company's Midlands Technical Centre in Leamington Spa, the Ricardo Driveline and Transmission Systems (RDTS) division has the mechanical, pneumatic, hydraulic, electrical and electronic disciplines required to engineer complete drivelines for a wide range of vehicles.

As an integral part of its operations, RDTS also embrace the company's motorsport activities and ultra-specialist prototype and low volume manufacturing facilities. RDTS' engineers have been responsible for a wide span of products on a global basis – from cost-optimised manual transmissions for developing markets to advanced and high performance systems such as the dual clutch transmission of the Bugatti Veyron.

Reliable quality

The company's impressive Leamington Spa facility has a dedicated machine shop with all of the resources necessary to manufacture either complete transmissions and driveline systems or single components. A recent £3 million + investment in machine tools and people, includes, computerised heat treatment, full form CNC gear grinding, spline and jig grinding and pallet change horizontal machining centres for case machining.

A major aspect of RDTS's recent investment was the purchase of a Hofler Helix 400 SK gear grinding machine. Nigel Walker, manufacturing engineering manager at Ricardo explains: “Having purchased our existing Hofler Promat 400 SK profile gear grinder six years ago, we have been delighted with its reliability and the quality of output. In fact, several of our visitors have been so impressed by the advanced capabilities of our older machine that they have subsequently purchased their own Hofler gear grinding machines.
“Even though our previous Hofler machine had given us sterling service, when the need arose for another gear grinder we were aware that other manufacturers' machines had progressed technically, so we considered several alternative makes.

“Although some of the available machines matched most of our criteria, the Hofler Helix 400 SK ticked all the boxes. In addition, our previous Hofler experience made the decision an easy one. Not only has the service we have received from Hofler been first class – the assistance we have received from Mark Maurice of Hofler's UK agent Micronz, has been of great help.”

He continues: “As the purchase was prompted by increasing demand for our output, I am happy to say that, following a trouble free installation and training period, our new machine is now turning out the anticipated quantity of high quality gears.

“Although our operators had the advantage of using our previous Hofler, despite the new machine's range of newly incorporated functions, they are finding it relatively simple to program and operate. Even though the Helix is used by our highly skilled personnel, the machine/operator interface is so intuitive, I'm sure that machine operators with lesser experience in the manufacture of gears, could quickly become proficient in the machine's operation.”

Many happy returns

Since the Helix 400 was first introduced in 1995, the range has been constantly upgraded, well-proven features have been improved and new modules, advanced functions and enhanced software options have been added. Ideal for the efficient production of both spur and helical gears, more than 400 machines have been shipped to customers around the world.

According to the manufacturer, gear manufacturers in the aviation and commercial vehicle industry, in addition to gear grinding companies hold the Helix in high regard as a virtually indestructible, flexible, and expandable machine for continuous operation – and as an investment that delivers a fast return.

With the grinding and dressing axes mounted directly onto a thermally stable, monolithic mineral cast machine bed, the innovative design of the Helix 400 ensures accuracy and repeatability. Using a powerful 15kW, water-cooled servomotor that is coaxially mounted on a 120mm 17,000rpm grinding spindle, the machine uses a 400mm grinding wheel and high pressure oil feed to provide rapid grinding cycles. In addition, the use of such a large grinding wheel minimises dressing cycles, reduces grinding wheel expenditure and lowers the risk of overheating when grinding and as a result, high stock removal rates are possible.

Due to the design of this machine smaller wheels of 40-100mm and 10-50mm can be used on two additional spindle mounting positions thus enabling the grinding of splines and gears in tight spaces. A large 160mm Dr Kaiser diamond dressing roll, with an 80mm dressing spindle, gives excellent rigidity, high accuracy and long tool life. To help provide high levels of wheel dressing speed, accuracy and repeatability, the 400's universal diamond dressing roll is positioned directly behind its grinding spindle. When undertaking a rapid wheel dressing procedure, the machine's grinding slide moves the wheel into the dressing position and performs the infeed motion, while the dresser slide provides the cross feed.

Valuable asset

The gear, which is mounted on the machine's worktable, performs all of the required indexing and stroking motions. Throughout both the dressing and grinding operations, temperature controlled, high pressure oil coolant is applied to the wheel, gear and dressing roll via specialised nozzles. Helix 400 standard accessories include an advanced grinding oil processing unit and a full machine enclosure incorporating an efficient oil mist collector.

Nigel Walker concludes: “In addition to manufacturing gears for high performance transmission systems, the Helix is proving to be ideal for our gear development work. Even though the machine represented a considerable investment, I'm sure that it will prove to be a significant technical and productive asset to Ricardo for many years to come.”

Ricardo
www.ricardo.com Micronz
www.micronz.co.uk