The PTI (Polygonal Turning Interface) is an innovative tool interface that raises the state of the art to a whole new level and allows for standardisation in turning machine revolvers. The main design feature of the interface is its eight-sided polygonal taper with flush fitting.

With the PTI system, static and driven tools are clamped using OTT-JAKOB’s quick-clamping system. The interface has holes for coolant and sealing air. An interface for data and energy transfer is also provided, so that the PTI can also be integrated in Industry 4.0 environments. The PTI is available in sizes PTI42, PTI54 and PTI65.

The PTI was developed as part of a joint research project in which OTT-JAKOB was a major participant. The ultimate objective is to standardise the shaft, holder and coupling. The steps necessary for this are current ongoing after a successful market launch. For further information visit

OTT-JAKOB Produkte  - PTI

The Difference

Excellent torsional stiffness and repeat accuracy
The polygonal taper allows for form-locking transmission of torsional moment. This design feature also makes precise repeat positioning possible. As a result, manually adjusting the tools is no longer necessary.

Best bending stiffness
Thanks to the flush fitting, the PTI system can withstand higher bending moment. The clamping option using four screws allows for additional bending stiffness.

Faster tool changing
The quick-clamping system from OTT-JAKOB saves significant time during tool changing and effectively reduces equipment costs. Tools are clamped and unclamped via a simple screw actuated with a torque wrench.

High compatibility
The PTI system is compatible with other interface solutions on the market. Existing tool technology can therefore continue to be used.

More flexibility
The standardisation of the PTI aims to reduce complexity by limiting the number of interfaces on the market. At the same time, it meets requirements for implementing flexible production with tool interchangeability across machines.

PTI Clamping Unit

OTT-JAKOB’s quick-clamping system for the PTI interface represents highly durable clamping technology for static and driven tools. Tools are fixed manually via a screw. Very high clamping forces are generated with extremely low actuation forces (80 kN at 40 Nm with PTI65). The resultingly high bending stiffness ensures a highly precise, secure fit and allows for the transmission of high torques. The PTI clamping unit is also suitable for automatic clamping.

The PTI product range from OTT-JAKOB is rounded off with a revolver flange with an eight-sided polygon that ensures energy transmission from the polygonal flange to the revolver disc.

PTI Clamping Unit