Beefed up with much more power, a tougher transmission and several key design changes, Case's fourth generation 30-tonne ADT, the 330, is now ' nding its way onto the market. Plant testers Geoff Ashcroft and John Woodward took the measuring equipment to Ireland to put it through its paces
THROUGH its Italian partner Astra, Case has been pushing out ADTs for several years now, gaining useful operating experience and feedback across the entire model range.
It is a range that currently includes four models: the 325, 330, 335 and 340, with payloads of 23, 27, 31 and 36 tonnes respectively. The latest round of engineering updates have just been applied to the 27-tonne 330 model, which Case reckons is one of its most popular.
'There's good demand for 30-tonne machines in southern Ireland and this is where we see most sales being made in the first 12 months, ' says Scot t Freeman, business manager for Case construction equipment.
Case has focused heavily on operator comfort with the 330, making changes to the truck's suspension system and enhancing the rubber-mounted structure with a specification that includes climatecontrolled heating and ventilation, windscreen wipers on the side mirrors and a heated seat.
'We're going at the market gradually and feeling our way to ensure that we put enough support in place to look after customers and machines properly, ' says Mr Freeman. 'By work ing with our dealer, Jim Macadam Equipment in Dublin, which has a lot of dump truck experience, we hope to make some solid progress in the sector.' Case has made a series of upgrades to the 330.
Out goes the earlier version's 280 hp engine in favour of a 315 hp Cummins QSM 11, which also dictated the use of a different transmission.
The 10.8 litre Cummins common-rail engine is Tier II-compliant and is both turbocharged and intercooled. The latter has required the front part of the 330's chassis to be lengthened by 200 mm to accommodate the intercooling pack. Variable geometry turbocharging on the six-cylinder engine is designed to combine a high specif ic power output with low fuel consumption. It also delivers 1,600 Nm of torque at just 1,000 rpm.
Case plans to keep push ing up the power. When Tier III emissions standards come into effect from July 2006, the manufacturer intends to give the 330 an extra 45 hp, adding further to the power-to-weight ratio that gives the truck an agile, nimble feel.
'The previous ZF 210 t ransm ission had a power limit of 300 hp, so the switch to ZF's beefier 260 gearbox should help overall reliability and longevity, ' says Mr Freeman.
The six forward, three reverse transmission features manual and automatic modes to simplify operation for those who like different levels of driver interaction. The transmission also comes with a lock-up torque converter that gives characteristics similar to a manual transmission unless it is making gearshifts, becoming an almost solid driveline once engine revs exceed 1,200 rpm.
As an option, the truck can be fitted with an hydraulic retarder, though the engine's standard Jake brake should offer long-term savings on service brake life, particularly as dry disc brakes are the order of the day for this model.
The truck's front suspension system still uses an oil-over-nitrogen suspension system but with larger-diameter cylinders to allow the pressures to be lower, resulting in a softer, more comfortable ride.
Case has also changed the design of the centre pivot bearing from a roller-type to a cone-type spherical bearing. The change gives a greater bearing surface contact, leading to more durability for the oscillation point, says the firm. This has been borne out so far by a series of tests in the USA in which the centre pivot bearing exceeded a 7,000-hour life cycle.
Elsewhere on the truck, the rear bogie has been revised, although cast steel dual rear suspension beams remain and general truck maintenance has been simplified. The one-piece bonnet is opened by the f lick of a switch that powers a hydraulic ram and the cab can be tilted sideways by 51 deg to give access to the engine, transmission compartment and main hydraulic components.
The tipping body's pivot-point is located on halfbearings to reduce friction, while body lowering time has been reduced by around five seconds through the use of an oil bypass line that takes 70 per cent of oil f low directly back to the tank, leaving just 30 per cent to run through the check valves. Drop times are now said to be close to 10 seconds.
Tipping gear is neatly located beneath the body using four-stage rams, rather than externally mounted , single-stage cylinders as favou red by many other manufactu rers. Case says such a design keeps the rams protected from overzealous side loading by wheeled loaders.
Case claims that the 330 has the widest chassis in the industry for a truck of its class, good for both traction and stability.
Only t ime will tell if Case has done enough in its ADT programme to make an impact as a serious contender in the UK's ADT market.
n See page 46 The 330's powerplant has gained 35 hp and a beefier gearbox to cope with the extra power, while a fu r ther 45 hp will ar r ive next year. Torque of 1,600 Nm is available from just 1,000 revs.
Intercooling on the turbocharger and a lock-up feature on the transmission improve fuel economy.
Case 330 Engine: 315 hp Cummins QSM 11-C , s i x- cy l i nd e r t u r b o d i e s e l Transm ission: ZF 6WG260, 6F/3R Payload: 27,000 kg Body capacity: 13 cu m (struck), 16 cu m (heaped) Tip angle: 67 degrees Dimensions: 2.93 m (w) x 3.64 m (h) x 9.79 m (l) Ground clearance: 0.63 m Load-over height: 2.84 m
Producti n testing
AT THE West Park indust r ial site at Shannon Airport, southern Ireland, contractor Brian O'Connell was busy earthmoving using two recently purchased Case 330 ADTs.
With a haul road offering a mix of gradients and descents over a 1,258 m circular route throughout the site, we were able to put the Case 300's transmission to the test hauling fill material from stockpile to construction site.
Our aim was to establish the truck's ability to move material productively and efficiently.
From the loading point, our haul road offered a six degree 30 m descent, before turning almost 180 degrees to continue a descent for a further 90 m before turning hard right, up onto the site's subbase road.
This route offered a level run for over 250 m, before climbing a further 250 m on a two degree incline. A four degree descent for a further 170 m resulted in hard braking to make a 170 degree r ight-hand tu rn before climbing a seven degree slope for 150 m then reversing into the tip area.
The empty return journey was a short, direct route through the middle of the site.
All measuring and recording equipment was supplied and supervised by Construction News.
Construction News would like to thank Darren McAdam of Macadam Equipment, contractor Brian O'Connell, site planner Hugh O'Donnell and operator Des Maxwell for all their help during this test.
Test 1: Auto mode With the transmission set in automatic mode, we ran six full cycles over the 1,258 m route to identify the Case 330's productivity potential.
All gear shifting and retardation on climbs and descents were fully automatic. The soil density was est imated at 1,899 kg /bank cu m , 1,519 kg / loose cu m, and the swell factor was 25 per cent.
Time taken to complete six cycles: 60 mins 34 sec Average cycle time: 7 mins 8 sec Average loading time: 2 mins 58 sec Average payload: 24.3 tonnes/load Total weight of mater ial moved: 145.8 tonnes.
Estimated output potential: 144.44 tonnes/hour Fuel consumpt ion: 18.9 lit res over a six-load cycle.
Hou rly fuel consumpt ion: 18.72 lit res /hou r Fuel consumption per tonne moved: 0.13 litres/tonne Tes t 2 : M a nu a l mo d e With the transmission set in manual mode, we ran six full cycles over the 1,258 m route to identify the Case 330's productivity potential. All gearshift points and retardation on climbs and descents were entirely at the mercy of experienced operator Des Maxwell. The soil density was est imated at 1,899 kg /bank cu m , 1,519 kg / loose cu m, and the swell factor was 25 per cent.
Time taken to complete six cycles: 56 m ins 46 sec Average cycle time: 6 mins 45 sec Average loading time: 2 mins 42 sec Average payload: 24.3 tonnes/load Total weight of mater ial moved: 145.8 tonnes.
Estimated output potential: 154.1 tonnes/hour Fuel consumpt ion: 19.4 lit res over a six-load cycle.
Hou rly fuel consumpt ion: 20.5 lit res /hou r Fuel consumption per tonne moved: 0.13 litres/tonne
The view from the cab
BY JOHN WOODWARD
MOST const ruct ion machines look much the same from a distance, distinguishable largely by the manufacturer's livery. This is particularly true of ADTs. Often an assembly of proprietary parts such as engine, transmission and axles, and with similar chassis and wheel configurations, ADT designs seem have changed little over the years, making it tricky to distinguish one from the other. A glance at the spec-sheet would be needed to give some clues.
It was going to be interesting to view at first hand and operate the latest offering from Case, the fou r th generat ion of 30 -tonner, badged 330.
The step up to the first rung on the access ladder is quite high for ground clearance but from then on the climb is easy, thanks to well-placed grab rails.
As you would expect, Case's ROPS cab inter ior is funct ional rather than luxu r ious and offers plenty of room with climate control and generous sound insulation as standard.
Depending on the quality of the haul roads or site conditions, driving an ADT all day long can be a gruelling exper ience, so it is of paramount impor tance to make su re the operator is comfor table.
The impressive air-sprung seat in the 330 is manually adjustable for leg length and all other adjustments for weight, backrest angle, lumbar support and heating are electrically operated from a bank of cont rols just below the seat squab.
It was very easy to find a comfortable driving position with the combination of seat and steering wheel adjustments. Forward vision is excellent down the sloping engine cover with good peripheral vision through the washed and wiped side windows supported with a plethora of heated and adjustable rear view mirrors.
Our test model also came with a rear-view camera that displayed on a small screen in the top right of the cab. The image can be continuously displayed or selected to operate only when reverse is engaged.
The dashboard is packed with easy-to-read instruments and system warning lights, while most ancillary controls are column-mounted on stalks beneath the steering wheel. The gearshift and tipping controls are on the right-hand console together with the park brake and differential lock switches. It is all very logical and easy to use but I found the LCD panel that relays gear selection a touch difficult to read in the bright sunlight.
The Cummins engine spins enthusiastically before f ir ing up and set tling into an uncharacter ist ic f luffy idle. But, when on song, the engine pulls strongly and remains suitably muted in the cab.
You can choose to operate the 330 manually or in fully automatic mode and we wanted to compare the performance and fuel consumption in both. Our operator, Des Maxwell, preferred to use the truck in manual mode given the amount of gradients throughout the haul, to prevent the truck from making excessive gear shifts ? but piloting an ADT can be a tedious task, and we suspected he enjoyed the interaction with the truck, rather than simply using a point-and-shoot approach via the automatic transmission.
The Case 330 is a nimble truck and in automatic mode it is an impressive machine with smooth and rapid up-shifts that are executed much quicker than can be accomplished manually. From rest at the loading point we were in fourth gear in no time, and downshifts were as instantaneous for the short uphill and sharp turn that followed.
There was no need to reach for the brake pedal, as the engine's Jake brake did all that was necessary to swiftly bring the fully laden machine to a controlled halt.
Tipping to 67 degrees is quick, giving a clean discharge of material. The internally mounted hydraulic cylinders look robust and are well protected inside the chassis. The machine's ride is smooth when loaded and only deter iorates slightly when not laden, thanks to the semi-independent front suspension and the high-quality seat.
Extremely dusty site conditions and speed restrictions prevented us from fully exploiting the potential of the 330 and there was no opportunity to operate in poor ground conditions.
But our tests revealed a slight difference in performance between manual and automatic modes using the same operator. Manual gear changes provided a 7 per cent improvement in output over automatic shifts but the automatic mode provided a 9 per cent saving in fuel consumpt ion. What mode you select will depend on you r pr ior it ies.
The 330 comes as standard with auto-lube, so with no regular greasing requirements routine maintenance is simple and amounts only to engine oil level, for which you have to raise the engine cover and pull the dipstick ? an easy task using an electro-hydraulically raised bonnet giving extensive access to the engine and ancillaries.
All remaining levels such as fuel, hydraulic oil and transmission oil can be seen through sight glasses and checked from ground level.
I found the Case 330 to be an impressive truck, despite being conventional in many ways. Good additional features such as the front suspension, rear axle mounting and the location of the tipping cylinders combined with an excellent engine and transmission package that makes it simple to drive mean that in pract ice most operators will probably leave the truck in automatic mode and let the 330 make the decisions, saving some fuel en-route.