Rotavator (Tractor PTO)

A rotavator is a PTO-driven secondary-tillage rotary tiller that prepares a seedbed and incorporates surface crop residue in a single pass. It has become the default seedbed-preparation implement in much of Indian agriculture because it replaces the sequential plough-harrow-leveller chain with one operation.

Function

A horizontal cross-shaft, carrying L-, J- or C-type tilling blades, is rotated by the tractor PTO at high tip speed. The blades cut, turn and pulverise the soil and chop surface residue, producing a tilth suitable for sowing with a Seed Drill or Twin Box Seed Drill.

Design and specifications

The rotavator runs at 540 (or 1000) RPM PTO input. L-blades are the default for medium soils and trashy conditions; J-blades are preferred for sticky paddy soils because they resist clogging; C-blades give a helical, low-load cut. Mini units 3-4 feet wide suit 15-30 HP tractors, 5-6 feet units need 35-50 HP, and 7-foot-and-above units need 50+ HP. Working depth is 6-8 inches.

Operation

The implement mounts on the tractor's three-point linkage with a PTO shaft connection. Working depth is set by the rear roller or the top-link, and forward speed is matched to soil moisture (lower speed in wet, sticky soil; higher speed in dry, friable soil). For puddled paddy, the rotavator is often replaced or supplemented by a Roto Puddler working with Cage Wheels Tractor.

Subsidy and adoption

ICAR-CIAE Bhopal coordinates the All India Coordinated Research Project on Farm Implements and Machinery (AICRP-FIM), under which rotary tiller designs are developed and tested. The implement is on the SMAM subsidy list with 40-50% individual-farmer assistance and 80% CHC assistance (Agri Machinery Dealer Ecosystem).

References

Understanding Different Types of Rotavator Blades. Tractorforeveryone.
Tractor Rotavator Price and Features. Tractorkarvan.
Farm Implements and Machinery. ICAR-CIAE Bhopal.