Replacing a long-serving Bell 25-tonne truck at the Guggenberger gravel works in Mintraching, a Bell B30E 4x4 has been working as a dump truck in production, material handling and moving overburden since the end of October 2017. The decision was taken to buy the 4x4 two-axle truck rather than the conventional 6x6 technology on the strength of its specific advantages.
With just under 500 employees, Guggenberger GmbH founded in 1949 and based in Mintraching near Regensburg is a construction company operating not just in its own region, with focuses on building construction, civil engineering and road construction. Back in the 1950s, the family company opened a gravel pit in the Danube flood plains – with gravel works and capacities for asphalt and ready-mixed concrete, the production of construction materials there was expanded in the 1960s and since then modernized at different times. Today, around 20 employees are working in extraction and the production of construction materials, predominantly to meet the demand at the company‘s own construction sites in the region.
A good 200 000 t river gravel is extracted by Guggenberger per year on around a hectare of open area in Mintraching. The suction dredger works down to a depth of 6 m, the material then being sent on an overland belt to the processing plant around 900 m away. In peripheral areas, during stripping of the around 60 to 70-cm-thick bed of humus and in the filling of exhausted pit areas, conventional loading and transport equipment is used with heavy excavators, 6-m³ wheel loaders and dump trucks, which parallel to that also guarantee production and reloading at the plant.
Advantages in sight
Up to mid-2017, a Bell B25D was operated for twelve years and around 13 500 operating hours in the pit and removing overburden as well as between silo discharge and bins. When it came to deciding on a replacement, Guggenberger again selected Bell Equipment – following detailed evaluation with the regionally responsible distributor Beutlhauser Baumaschinen, the company opted for the current two-axle Bell B30E 4x4 truck, which under the specific circumstances promises better long-term cost efficiency.
In actual fact, the up to 1500 m-long transport circuits in Mintraching have well-constructed roadways that do not require 6x6 traction. While the 4x4 two-axle truck scores points here with relatively low tyre wear, it is able to really show off its strengths in the often narrow plant traffic network with relatively short total length and small turning radius: in direct comparison with the three-axle Bell B30E, the 4x4 boasts an around 1.5-m-smaller turning radius (14.6 m), thanks to much shorter rear end with redesigned dump body, it makes manoeuvring much easier. Without centre axle rubbing against the ground, the roadways between the stockpiles are spared, which is good for the fast handling of the company‘s own or other trailers.
Identical to the conventional B30E apart from the swivel/
articulated joint, the 4x4 two-axle truck comes with reliable large-series technology for drive and steering. The 246 kW Mercedes-Benz-turbodiesel with Allison sixspeed automatic transmission effects propulsion, the preselectable gearbox retarder and large-dimensioned oil bath multi-disk brakes on all wheels ensure safety. The extensive series package of driving and loading assistants guarantees on the basis of real-time measured data (on-board weigher, pitch and roll sensors, etc.) safe and comfortable working.
With nominal 28 000 kg, the two-axle truck has the same payload as the 6x6-30-tonne truck – correspondingly high are the reserves of the solidly munted 36-t rear axle with 29.5R25 tyres (front: 23.5R25). Especially as the redesigned dump body with flat bottom with 18.5 m³ (SAE 2:1) offers one cubic metre more volume than the V-shaped 6x6 dump body. In Mintraching, the B30E 4x4 with automatic tailgate loads around a cubic metre more, the short dump geometry accelerating especially the silo loading of easy-flowing sands and gravels. During unloading, the shorter hydraulic cylinders bring faster dump cycles – more important for specific applications (enclosures, underground use) is, however, the lower tipping height that the B30E 4x4 needs with identical, freely configured 70 °-tipping angle compared to the conventional 6x6 dump truck.