Earthmoving Report: Automated System Keeps Tracks Tight

Aug. 3, 2011

Gehl has engineered an automatic track-tensioning system that automatically keeps the tracks on its RT Series compact track loaders at the correct tension as the machine operates. The feature has been introduced on the company’s RT175 and RT210 CTLs.

Gehl has engineered an automatic track-tensioning system that automatically keeps the tracks on its RT Series compact track loaders at the correct tension as the machine operates. The feature has been introduced on the company’s RT175 and RT210 CTLs.

The patented HydraTrac system elimates the need for manually tensioning the tracks before operation and keeps the tracks tight during operation, says Bob Claas, track loader design engineering manager.

“According to track and undercarriage manufacturers, one of the biggest causes of premature track and undercarriage component failures is improper track tensioning,” Claas says. The system keeps the tension adjusted when the machine is running and also adjusts it to the proper loading, he says. The system is tied into an existing hydraulic circuit that automatically pressurizes a load device to maintain proper tension. It then relieves the tension when the machine is shut off.

“Over-tensioned tracks not only increase wear, but also require more horsepower to drive and turn the loader,” says Brian Rabe, track loader product manager. “HydraTrac ensures that all hydraulic horsepower is efficiently utilized resulting in high performance with reduced owning and operating costs.”

The system also provides “virtually tool-free” track service access, the company says. With the flip of a switch and removal of a lock-plate, the tracks de-tension and can be removed without the use of a pry bar or to allow access to the undercarriage track system.

Operators can choose from five “drivability” settings offered by the standard Electro-Hydraulic 5x5 Drive Control System on the RT Series. Joystick sensitivity, position reaction, engine response, anti-stall, and pump swash plate position can be changed to match application and operator preference. “It gives the ability to tailor drivability to the unit,” Rabe says.

Optional speed control allows the operator to set up the machine to run at full engine rpm and vary the speed down to within 2 percent of the actual low speed maximum. “For example, if you’re running a trencher when you only want the machine to run so fast, you can tailor the system to match the application,” Rabe says.

Torque has been increased on the RT Series. Model RT175 now produces 11,840 pounds of tractive effort; model RT210 produces 12,359 pounds. Yanmar diesels power the two models: 68.4 net horsepower to the RT175 and 70.7 horsepower to the RT210.

The RT175 has an operating capacity (at 35 percent tipping load) of 1,750 pounds; the RT120 is 2,100 pounds. Bucket breakout measured at the tilt cylinder is 5,189 pounds and 5,492 pounds, respectively, for the two CTLs.

A large rear hood and swing-out door provides access to the engine service points. The ROPS/FOPS tilts back on gas-spring assist cylinders to access hydraulic components and electronics. Additionally, the patented foot pod tilts forward out of the way for cleanout and access to the fuel tank and hydraulic components.

Gehl positions the extra-large operator’s station for comfort and productivity. The joystick controls are mounted directly to the suspension seat frame, allowing them to move with the operator as the machine travels. This reduces operator fatigue, enhances comfort in adverse conditions, and allows precise control for performing delicate tasks, according to Gehl. Controls, armrests, restraint bar and foot pod depth are adjustable to accommodate any size operator.