Developed for the VIPER grinding of nickel alloys, wheels and tires have a porous bond system is capable of absorbing high dynamic loads and increase the number of parts ground/wheel by 30%

Austrian abrasives manufacturer, Tyrolit, Rolls-Royce and Raysun engineers invented and then developed the Viper grinding process to machine difficult nickel alloys. Now Tyrolit has launched its Viper Ultra range of wheels and tires, which greatly extend grinding performance on the normally difficult to machine nickel alloys, said the company.

Viper Ultra wheels have a new, patented matrix and are made using a sintering process that closely controls wetting and coating of the grain surface, which in turn improves bonding of the grain.

The highly porous bond system is capable of absorbing high dynamic loads without damaging the bond bridges, resulting in optimum use of the abrasive grain.

* Wheel life extended - benefits include better form holding and profile retention, which reduces the dressing frequency.

Wheel life is therefore extended and there is less wear on the diamond roll dresser.

Lower grinding forces result in reduced stress on the component and workholding system.

Power consumption is less and the lower heat input to the workpiece minimises the risk of burning.

Cool cutting is particularly important when grinding nickel-based aerospace components, such as turbine blades, rotor blades and nozzle guide vanes, which are primary applications for VIPER grinding.

* Productivity improvements - Tyrolit told manufacturingtalk.com that two sets of comparative, non-CD grinding results on nickel aerospace components using Viper Ultra wheels and their predecessors show the dramatic productivity improvements that may be achieved.

A Makino iGrinder G5 was used to grind the dovetail form on a rotor blade in two operations.

The machine was fitted with a Viper Ultra wheel, 220mm diameter by 25mm wide, running at 40m/s.

Table speed was 2m/min and infeed was between 0.1 and 2.0mm, depending on the operation.

A 30% increase in the number of components ground per wheel from 200 to 260 was achieved as well as a 35% increase in productivity.

The result was an annual cost saving of EUR 42,000, based on 35,000 blades/year.

* Blade fir tree roots - in a second application, the fir tree root form of a turbine blade was ground on a Bridgeport FGC 2 in four operations using a 250mm diameter by 25mm wide Viper Ultra wheel running at 40m/s.

Table speed was 1.5m/min and infeed varied from 0.1 to 1.5mm.

Production per wheel jumped from 150 to 250 parts/wheel - a 67% increase - and productivity was 30% higher.

An annual cost saving of EUR 20,000 was achieved, based on 20,000 components/year.

A number of products recently introduced to the UK will also feature on the Tyrolit stand, at the UK's MACH 2008 machine tool exhibition, as follows.

* CSS Ultra - during high performance, external cylindrical grinding processes, there is a build up of heat in the grinding area.

Increasing forces due to wear constantly weaken the grain and bond structure.

With high stock removal volumes, the boundary layer between these component parts of the wheel is heavily eroded.

Tyrolit's CSS Ultra improves grinding performance by restructuring the micro architecture of the grinding wheel.

It has been achieved using high quality materials along with an innovative sintering technology, enabling the abrasive grain to withstand much greater loads when in use, without breaking away prematurely.

The automotive and bearing industries are particular target markets.

* Polaris - the new specification of the Polaris product line allied to the use of new CBN grains promote maximum tool life, traverse speeds and stock removal.

Controlling layer properties during the electroplating process using a strong, laminar nickel matrix allow the CBN layer of the grinding wheel to achieve previously unattainable adhesion strength for high performance, external cylindrical grinding, especially in the automotive industry.

* Genis - in developing Genis, Tyrolit has introduced a new bond system that makes it possible to guarantee optimal wetting of the CBN grain, even with very low levels of bond content.

Through careful choice of composition of the bond components, crystallisation is specifically controlled under selected firing conditions.

Tyrolit told manufacturingtalk that this makes it possible to achieve porous structures with high mechanical strength that exhibit maximum resistance to the effects of cooling lubricants.

The cool grinding specification of the high-performance tools reduces grinding forces and makes efficient use of the CBN grain.

Lower grinding forces, minimum tool wear and maximum profile retention are confirmed in practice, opening up a wide range of application possibilities, again with the automotive sector very much in mind.

Startec-HP - for low cost, high productivity manufacture and resharpening of solid carbide and high speed steel drilling and milling tools and saw blades, a new generation of diamond impregnated wheels and tires has been introduced by Tyrolit.

Called Startec-HP, they combine an improved bond, new abrasive types and a new core.

The easy-cutting bond system results in outstanding cooling characteristics during creep feed grinding of flutes.

The products are easy to dress, which is particularly important for profile wheels.