SP-852H: two-rotor delivery rake with hydraulically adjustable working width
The SP-852H is designed simply and efficiently. Hydraulically folding arms, each carrying a rotor, are mounted on the main frame of the machine. The machine's swathing is designed on a middle row, the width of which can be conveniently set by the machine operator thanks to the hydraulically adjustable rotor pitch. The working width can be up to 8.5 m, which makes it suitable for medium areas.
The SP-852H is a pulled machine that is equipped with a rear steerable axle. A smaller turning radius is thus required when turning or tossing, making the work more efficient. The total weight of the machine is 2180 kg yet tractors with power outputs from 60 hp (45 kW) are sufficient to operate the machine. A category II suspension is required to connect the delivery rake to a tractor.
A 540 rpm PTO shaft and two hydraulic circuits are required to operate the machine. One circuit is for tilting the arms from the transport position to the working position, the other circuit is for extending the rotors to the required working width/row. The technical requirements are easily met even by older tractor types. The rotors are then driven by a simple but effective T-gearbox located under the machine frame.
The working width can be adjusted via a pair of hydraulic cylinders controlled by the operator from the tractor cab. With the maximum working width of the delivery rake set at 8.5 m, rows of 2.1 m wide are formed, with a minimum working width of 7.6 m, rows of 1.2 m wide are formed.
As with all ROZMITAL delivery rakes, the SP-852H rotors have a closed gearbox with a permanent oil fill. This is not grease or liquid lubricant, but real oil that can be drained and changed as with a gearbox. It is the sealed case that ensures continuous and thorough lubrication of the pulleys and the rocker arm and reduces wear on the individual parts of the rocker mechanism.
Another interesting feature is the mounting of the rotor pinion in a roller bearing on a special pin. This solution increases not only the reliability of the pinion, but also the life of its gearing and thus the entire machine. In addition, the closed gear system has a positive impact on the overall noise level of the rotor during operation, which is lower.
The overall diameter of the rotor housing is large, which ensures sufficient bearing distance between the individual arms and thus the strength and operational reliability of the individual rotor arms.
The large SP-852H rotors have a diameter of 3.76 m and are fitted with 10 working arms each. There are four double fingers on each arm. The rake height is adjusted on each rotor individually and mechanically, with the operator using the auxiliary rotary levers above each rotor. By turning to the right or left, the rake is moved away from or closer to the mat.
A benefit of the machine that farmers clearly praise is its excellent ground following. This is due to several aspects. Firstly, the loose attachment of the machine's arms, which means that the rotors are not dependent on the position of the frame, and the tandem four-wheel chassis, which are located under each rotor (standard equipment). The chassis wheels are located just behind the working fingers, so that the rakes can follow the ground well, and also increase the stability of the rake.
On request, the harvester can be equipped with hydraulic circuit locks for better work and stability of the machine, especially in hilly terrain. Generally, in the transport position, the arms together with the protective frame are hydraulically raised to a vertical position. During transport, the rakes must be placed on a beam designed for this purpose. An interesting and practical solution is that the rotors automatically return to the transport position when the arms are folded down.
The SP-852H is a robust helper that can handle both hay and haylage. Find out for yourself, just contact your nearest authorised ROZMITAL dealer and let them demonstrate the machine or otherwise get to know it better.