Hytec & Bosch Rexroth Germany develop world-first hydraulic solution for tracked carriers
Bell Equipment in the U.S. needed to ensure that its new range of tracked carriers (TC 7 & TC 11) performed optimally in soft underfoot conditions without negatively impacting the ground. The equipment also had to be able to operate in environmentally sensitive areas where ground compaction is unacceptable. The combined efforts of Hytec South Africa and Bosch Rexroth Germany resulted in a hydraulic solution that exceeded these requirements.
Bosch Rexroth Germany assisted with the required system calculations and made effective recommendations for the selection of components for the hydrostatic drive system used. Components included the prototype tandem drive pumps, motors and planetary reduction drives. Hytec ensured that the hydraulic drive component installation by Bell Equipment engineers was in accordance with the Rexroth specifications.
Data from Bosch Rexroth Germany enabled Bell Equipment’s engineers to conduct installation checks and commission the hydraulic system. Subsequent to prototype completion, extensive durability and performance tests (simulated normal operating procedures) were conducted at Bell Equipment’s Richards Bay factory. As the request for this specified equipment originated in America, extensive testing was also carried out on customer sites in the United States.
Bosch Rexroth products and components used in Bell Equipment’s TC range include tandem closed loop pumps for oil flow and drive pressure; variable displacement piston motors to drive the tracks; and planetary reduction drives. These drives, when placed between the piston motor and track, multiply the delivered torque.
A combined effort
“Fine tuning and optimisation were done by Bell Equipment engineers, in collaboration with Bosch Rexroth Germany’s engineers,” explains Berndt Wichmann, Hytec South Africa Regional Technical Manager, KZN Region. “This teamwork helped to achieve optimal vehicle control and performance.”
“Feedback from the intensive U.S. test programme was encouraging,” adds Ryan Lombard, Product Designer for Bell Equipment. “It surpassed our expectations, with all features designed into the machine having proved themselves in the various applications.”
Demand for this type of vehicle in the construction and mining industries stems from Bell Equipment’s U.S. customers requiring a niche solution for soft underfoot conditions. This initiated extensive market research and, after a stringent design process, the development of the TC7 and TC11 tracked carriers. Each meets the needs for short haul tasks in mining, construction, oil & gas and the pipe-laying industries for work in soft underfoot conditions.
“We are now an official production partner to the Bell TC range, offering continuous support to machine production and the aftermarket, as well as technical and future product development support,” Berndt enthuses.
Hytec and Bosch Rexroth have previous experience with Bell Equipment. They have supplied various componentry and helped develop hydraulic systems for a range of mining, construction and agriculture machinery, as well as equipment for other industries.
The range of tracked carriers perform optimally in soft underfoot conditions and environmentally sensitive areas without negatively impacting the ground.