Sauer-Danfoss Introduces Gear Motor for Off-Road Applications

Sauer-Danfoss, Lincolnshire, Ill., has introduced its new D Series cast iron gear motor, which provides a 4,000 psi solution in a ductile, three-piece housing, complete with an electrohydraulic proportional relief valve. Suited for heavy-duty fan drives and powering work functions, it complements the Sauer-Danfoss D Series cast iron gear pump.

“Many off-road applications are known for extreme performance requirements, like the ability to consistently perform under varying high-load conditions and withstand dust, dirt and high temperatures,” said Jeff Brenner, product portfolio manager. “Enter Tier IV and Stage III B engine emission requirements and you have engines running at even higher temperatures, with greater need for cooling.”

The D Series motor is an excellent choice for variable speed fan drive systems, according to the company. In addition to handling high cooling demand, an EH proportional relief valve maximizes available machine horsepower by providing cooling only as needed. The electronic interface makes the D Series motor fully PLUS+1 Compliant to integrate with PLUS+1 microcontrollers and other compliant products including sensors and graphical displays.

“With D Series motors, our focus is on four key product attributes: increased performance, efficiency, extended life or durability and installation flexibility,” Brenner said.

The D Series motors exceed the capabilities of aluminum motors in applications requiring high pressure, 4,000 psi vs. 3,000 psi, high temperatures and duty cycles. Fan speeds can be controlled to maintain optimum engine and hydraulic system temperatures. Fan reversing capability enables a radiator cleaning cycle. When used in conveyors, the D Series motors offer excellent starting torque to control the conveyor speed while optimizing feed rates and maintaining speed under varying load conditions.

The use of the EH proportional relief valve makes fan drives up to 50 percent more efficient than direct or belt drives. In the possibility of valve failure, fan speed defaults to the highest setting to maintain cooling integrity. The D Series motors also incorporate high temperature seals and a dust-resistant shaft seal, which improve performance under extreme temperature and pressure conditions – and extend operating life. The bronze sleeve bushings in the front flange are lined with Teflon PTFE, and provide increased radial load capability before requiring the use of outrigger bearings.

The D Series compact design is 20 percent smaller than a conventional motor. Shorter length and consequent higher power density help to ease installation in tighter places. The side or rear port options come in a variety of styles, and add to greater machine design flexibility.

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