Two international standards govern how an implement connects to a tractor. ISO 500 covers the rear power take-off (PTO), and ISO 730 covers the rear three-point linkage.
Indian implement makers know both, but they build most often for the tractors common in India. You need to check that each machine matches the tractors your customers actually use.
PTO types under ISO 500
ISO 500 defines the PTO shaft size, spline, speed and position. The three main shaft types are:
- Type 1 is a 35 mm shaft with 6 splines, used at 540 rpm.
- Type 2 is a 35 mm shaft with 21 splines, used at 1,000 rpm.
- Type 3 is a 45 mm shaft with 20 splines, used at 1,000 rpm on larger tractors.
What PTO speed means for you
Most rotavators, threshers and small implements from India run at 540 rpm with a Type 1 shaft. Many tractors also offer an economy PTO setting, which reaches the standard shaft speed at lower engine speed.
Running a 540 rpm implement on a 1,000 rpm setting overspeeds the gearbox and can be dangerous. Make the rated PTO speed clear on a label and in the manual.
The implement's PTO drive shaft must have the right spline at the tractor end and a guard along its length. A shear bolt or slip clutch protects the gearbox from shock loads.
Linkage categories under ISO 730
ISO 730 groups three-point linkages into categories by tractor power. Categories 1, 2, 3 and 4 run from small to very large tractors. Narrow versions, marked N, exist for some categories.
Each category sets the hitch pin diameters, the spacing between lower hitch points and the mast height. Category 1 lower pins are roughly 22 mm and Category 2 roughly 28 mm, so a Category 1 implement does not fit Category 2 arms without bushes.
Many Indian implements are built as Category 1 or Category 2, and some carry both pin sizes or reducing bushes. Ask the maker which category each model uses and whether bushes are supplied.
Checking the match
List your common tractor models with their PTO type, speeds and hitch category. Compare that list with each implement before you order. Then check the PTO shaft length, because a shaft that is too long can bottom out when the implement is raised.
If your market uses quick-attach couplers, check the implement's hitch frame against the coupler type. Couplers need the hitch points placed within tight limits, and some Indian frames are not built to them.
For the power side of the match, see what tractor horsepower each rotavator size needs. For guard and safety rules, see what safety rules apply to agri machinery.
Next step
We check hitch, spline and shaft details against your tractor list before production. To make sure your range fits your market, book a free sourcing review.