Case IH is launching articulated tracked tractors with continuously variable transmission (CVT). Case say the move is designed to bring the benefits of improved fuel efficiency, ease of operation and reduced operator fatigue to the highest horsepower sector of the tractor market.
New for 2017 is a range of three Case IH Quadtrac CVX models which will complement the existing line of five models with the established standard powershift machines. The new CVXDrive transmission offers stepless travel from standstill up to 40 km/h, and can be operated to work at a desired forward speed or engine speed, with Automatic Productivity Management software then able to adjust engine and transmission management accordingly, explains Hans-Werner Eder, Case IH Quadtrac product marketing manager.
“At 613 peak horsepower, the 540 CVX, which is the flagship in the Quadtrac CVX range, offers the highest available power of any CVT tractor,” points out Mr Sommer.
“The other models in the range are the Quadtrac 500 CVX and Quadtrac 470 CVX, which have respective maximum power outputs of 558hp and 525hp.
“Case IH is a name synonymous with high-output equipment, and with a history in CVT development for mid-power tractors that dates back 17 years, we are now bringing this technology to the top end of the tractor market, so that owners and operators on the largest arable enterprises can benefit from the same fuel efficiency and operational advantages.”
The Quadtrac CVX tractors are powered by electronically-controlled 12.9-litre Cursor 13 six-cylinder engines from sister company FPT Industrial, with a single-stage turbocharger on the two smaller tractors and a two-stage turbocharger in the 540 model. On this tractor, the smaller turbocharger delivers low rpm responsiveness, while the second, larger unit provides maximum boost at high rpm. Each turbocharger has its own cooling system to provide 30 per cent faster response under load.
The engines meet Stage IV emissions legislation through the use of the Case IH Hi-eSCR system, which also ensures that fuel efficiency is optimised. On the largest model in the Quadtrac CVX range, the Quadtrac 540 CVX, rated power (according to ECE R120 2) is 543hp, while Engine Power Management, introduced under load, takes this to 598hp, both measured at 2,100rpm rated engine speed. Maximum power of 613hp is achieved at 1,900rpm, and maximum torque of 2,607Nm at 1,400rpm. The tractor has a diesel capacity of 1,230 litres and a DEF (AdBlue) tank that holds 322 litres.
Continuously-variable transmissions have, until now, never been available in an articulated tracked tractor. The CVXDrive transmission in the Quadtrac 470, 500 and 540 CVX models brings with it a number of benefits, including ease of use particularly for inexperienced operators, faster acceleration to field or road speed, reduced operator fatigue, full power availability at low ground speeds for special applications/implements, and full hydraulic flow availability at low ground speeds, for applications such as drilling/planting. The result is increased productivity with faster cycle times and maximum fuel efficiency.
Providing stepless travel from 0-40km/h, and 0-18km/h in reverse, CVX allows the storing of three adjustable target speeds from 0km/h to 40km/h, adjustable via the thumb-wheel and buttons on the Multicontroller. The transmission incorporates a kick-down feature which ensures maximum acceleration, and 40km/h is achieved at just 1,640rpm. The transmission features four mechanical ranges, for maximum efficiency and operator comfort, with automated range-changing, and the first time 100% mechanical power transfer takes place is below 10 km/h, matching heavy draft application requirements. Four multi-plate wet clutch packs, mounted on the four planetary gear sets, change the ranges without power interruption, with equal clutch speeds guaranteeing smooth shifting without clutch wear.
The tractor can be stopped temporarily – such as at road junctions – using only the brake pedal, with the tractor, before returning to its previous speed once the pedal is released. Fast reduction of forward speed is possible by drawing back on the Multicontroller. Three different response levels for acceleration, deceleration and power shuttle modulation can be set using the Multicontroller armrest.
“CVX can bring a wide range of engine, fuel and work advantages to Quadtrac owners’ businesses,” believes Hans-Werner Eder. “They include reduced engine speed to optimise fuel efficiency, and, for those operating PTO-powered equipment, enhanced operation through the achievement of uninterrupted peak power via stepless speed progression.
“The addition of continuously-variable transmission to the Quadtrac for the first time means these models have the potential to mark a whole new chapter in the contribution of high-hp tracked tractors to arable agriculture.”