Design for Industry Hydraulic rotators let harvesters revolve eely

Forest machine manufacturer Ponsse is launching the new HH360 rotator, which lets the harvester head freely rotate 360° without limitations. The harvester head speeds up wood processing, makes the operator’s job easier, and reduces hose failures.

The product was developed in close cooperation with hydraulic motor and rotator manufacturer Black Bruin, and Ponsse has exclusive rights to the product for forest machine use.

“The HH360 is a combination of the well-known and durable radial piston technology of Black Bruin’s harvester rotators and Ponsse’s innovation,” said Tero Ylä-Mononen, Black Bruin’s R&D manager. “Thanks to the structure, the torquetransmitting components are wear-proof, and the rotator maintains a firm grip throughout the machine’s service life. The rotator is extremely accurate in use and responds precisely and consistently to the user’s actions.”

Due to the radial piston rotator’s high e ciency, just 20 lpm of oil flow su ces to operate. Operating costs are low, and the rotator is easy to service if needed. This means that service life can be extended far into the future.

The powerful and exceptionally energy-e cient HH360 rotator is available for multiple Ponsse harvester heads when mounted as a loose-head installation.

The most important factor in choosing a rotator product is the application’s load capacity requirements. Black Bruin’s harvester rotator design is made for heavy-duty use and is based on its radial piston motor, giving the same highly e cient power as the motors. Black Bruin harvester rotators are rotary housing, which means the rotator shaft (cylinder block) remains in place while the rotator is running.

The rotation of the motor is achieved by feeding pressurized hydraulic fluid through the rotator distribution head to the distribution valve. The distribution valve directs the flow through the cylinder block to the pistons, which are on a power stroke. The pressure pushes the pistons, and the cams roll outwards against the cam ring on the housing (distribution head). The waveform of the cam ring transforms the force into torque. When the pistons reach the end of the power stroke, the distribution valve closes the flow to the pistons and switches the pistons to a return stroke. The cam ring pushes the pistons back into the cylinder block, preparing them for the next outward power stroke.

Harvester rotators are used for cut-tolength and full-tree wheeled and tracked harvesters, while grapple rotators are for forwarders, timber trucks, and bulk material handling. Unlike harvester rotators, the radial piston grapple rotator housing remains in place, and the shaft (cylinder block) rotates.

A rotator connects to a boom or crane tip with a link and pin kit, and brakes can be installed to dampen the harvester head or grapple swinging. In harvester rotators, links enable the use of up to four brake kits, while links in grapple rotators enable up to two brake kits. Both rotators can also be used without brakes. DW

Off-highway