When developing the new CT630HD road-train triple model Cat Trucks engineers says they expanded on the foundations proven by the CT630LS model to develop a unit to operate efficiently and reliably at gross weights up to 131 tonnes.
Powered by the Cat C15 engine which satisfies Australia’s emissions regulations without the need for complex SCR or EGR emissions technologies, several key areas were identified to bring the CT630HD to Cat’s desired level for triples work.
The most obvious changes are a deeper, blackened grille and a higher cab stance which along with giving the CT630HD a boldly unique identity, delivers the mutual benefits of optimised airflow and reduced engine fan engagement in high duty cycles.
Specific enhancements included a raised, heavier duty frame for bull bar and tow-pin fittings, a high-flow twin cylinder air compressor to facilitate greater air delivery in multiple trailer applications and critically, increased air cleaner capacity with the introduction of a centrifugal pre-cleaner into the existing air cleaner assembly.
Meantime, front axle rating was boosted to 7.3 tonnes with the optional Meritor MFS73 beam which runs a narrower track width to accommodate the wide profile 385/65R22.5 steer tyres preferred by many road train operators. With standard 295/80R22.5 steer tyres, the CT630HD employs the wide-track version of Meritor’s MFS front axle rated at 6.5 tonnes.
Front suspension is a tapered three-leaf parabolic spring package rated at 7.3 tonnes.
Cat Trucks engineers also saw the need for an upgraded steering system. Consequently, a Sheppard ‘slave’ gear is now available for fitting to the left-hand side frame rail, effectively creating a dual gear steering system which not only maintains high standards of road handling but also distributes the steering load across both chassis rails rather than imparting full load on a single steering gear on a single rail.
Similarly, chassis rails of the CT630HD have been strengthened with the introduction of long L-shaped inserts extending from a position forward of the fuel tanks through to the tapered rear of the chassis.
The rear axle assembly has been upgraded to Meritor’s RT50-160GP drive tandem rated at 22.7 tonnes (50,000 lb) and offering rear axle ratios from 3.9 to 4.1, 4.3 and 4.56:1. In standard form, the Meritor layout features steel hubs, a power divider lock and cross diff lock on the rearmost drive axle. Optionally available are alloy hubs, an additional cross-lock on the forward drive axle and a lube pump for the rear axle assembly.
Rear suspension is Hendrickson’s Primaax EX air suspension which has been bolstered with the fitment of heavy-duty transverse torque rods.
On the inside, drivers are comfortably accommodated in the fully integrated 56 inch (1422 mm) sleeper cab.
Yet while the CT630HD has been developed essentially to answer the call for a triples-rated Cat truck, maintaining operational versatility was a critical factor according to Cat Trucks chief engineer Adrian Wright.
“Our primary goal was to create a truck for road train work up to 131 tonnes, but not at the expense of putting so much weight into the truck that it would lose the viability to also operate effectively as a B-double or B-triple.”
