Flexible valve platform for individual tractor concepts

The new SB24/SB34 mobile hydraulic valve family from Rexroth is consistently built according to the modular principle and simplifies integration into the machine

Advertisement

Significantly more compact, simpler installation and even more flexibly adaptable to individual tractor concepts: With the new sandwich valves in the SB24 and SB34 designs, Rexroth makes a consistent modular system for auxiliary directional and hitch control valves available to mid and high-end tractor manufacturers. Independently of the type of actuation (mechanical/electrohydraulic) or flow rate (up to 120 or 170 l/min), all sections are can be freely combined with each other and always result in a compact control block with uniformly aligned ports. The latter ensures optimal integration in the machine. For the new design, Rexroth used the SB23/SB33 family's decades-long application experience in hundreds of thousands of tractors worldwide.

Farmers and foresters expect comprehensive functionality with high work performance for tractors starting from 88 kW (120 hp). With the new SB24/SB34 valve platform, Rexroth expands the scope for tractor OEMs to fulfill requirements with tailor-made, energy-efficient hydraulic solutions. The new platform includes a mechanically operated configuration as well as electrohydraulically actuated valves with a flow rate of up to 120 l/min for the SB24 and 170 l/min for the SB34 respectively. This allows tractor manufacturers to economically implement the trend toward higher oil flows as well as toward the electronification of mobile hydraulics. The hitch valves for the Electrohydraulic Hitch Control EHC from Rexroth are optimally adapted to the new SB24 and SB34 sections. They are seamlessly integrated into the SB control block and cover the whole range of single- and double-acting system solutions with scalable additional functions.

The new SB family's modularity in function and flow allows for a high level of configurability of the working hydraulics. Rexroth strengthens this approach through the standardization of the flange ports and the widths (44 mm). The hydraulic connections are uniformly aligned in all flow sizes and types of actuation. The combination of up to seven valve sections for different flow rates in a modularly built control block enhances the cost effectiveness: It reduces the piping efforts and provides exactly the energy required by each of the consumers. Using the end valve version, the end plates of the control block (which are necessary in other systems) are not needed, which results in a smaller installation space.

The new SB family reduces the energy consumption of the mobile hydraulics using load sensing and supplies the consumer consistently. The newly designed SB24-M, SB24-EHS1 and SB34-EHS1 valves lower internal friction and pressure losses in comparison to previous versions. In this way, the new generation achieves the requirement for a further reduction of diesel consumption and increases the maximum hydraulic power that can be called up. At the same time they support a broadened pilot oil pressure range of 17 to 25 bar. This makes the use of external pilot oil supply easier and therefore lowers the system costs. Furthermore, the new valves make maintenance easier with their exchangeable pilot modules. The electronics are encapsulated and protected from external influences.