8-fold polygonal tool interface for

turning machines


An eight-fold polygon is the centerpiece of the polygonal turning interface (PTI) – a design element for high performance and accuracy.


The standardized contour of shaft and receiver is open to everyone and creates the conditions for a comprehensive supplier platform.


The new PTI interface is an upgrade for your lathe. Highest technological performance guarantees economic production.


A turret lathe is only as good as its tool interface. Discover the possibilities of the new PTI interface for your flexible production. Improve the quality of your workpieces and increase the productivity of your production.

The interface between turret disk and toolholder is a crucial factor – the pti-working-group supports you.


EMO Hannover 2023

At EMO Hannover 2023, the companies Heimatec, Mimatic und Ott-Jakob will present the standardized turret interface PTI (ISO/CD 5686-1, -2, -3). Get important information from our specialists on a development that will make your lathe even more powerful. We will show PTI toolholders and driven tools as well as a PTI clamping system for manual quick change. For the automation of turret lathes, concepts and solutions will be presented that enable automatic tool supply with automatic clamping and handling and thus low-manpower operation.


The companies of the pti working group have submitted the PTI standard proposal to DIN in May 2019 after finishing of various successfully completed research projects. The proposal includes the three parts: shank (1), receiver (2) and coupling (3). The proposal was adopted in 2019 by the national working committees NA 121-02-05 AA “Tool holders and machine/tool interface” (DIN) and NA 122-59-01 AA “Machine-side interface for tool holders” (VDW) in Germany. The DIN and VDW committees then forwarded the DIN proposal to international ISO standardization and prepared an international draft standard. The PTI draft ISO/CD 5686-1, -2, -3 was adopted by the international committee ISO/TC29/SC9 with the participation of countries important in the industry, such as Sweden, France, Germany and Japan, in August 2022. International standardization will be completed with the publication of the PTI standard in summer 2024.

PTI in own series production

OTT-JAKOB not only offers manual clamping systems and polygon flanges for the PTI interface, but has also equipped a lathe (GMX 400) in its own production with a PTI turret disk. With tool holders from WTO and Heimatec, the machine runs in series production and guarantees the highest manufacturing quality thanks to the highly accurate PTI interface. With the PTI clamping system from OTT-JAKOB, the PTI tool holders are changed easily and quickly in continuous operation, helping to reduce non-productive time.

Measurement-based vibration tests of the machine with the previous VDI interface compared to the new PTI interface have shown that the entire machine is up to 10x stiffer dynamically. The lower compliance of the machine with PTI toolholders leads to remarkable tool life improvements.


Automotive Parts Manufacturing

Precision Parts Manufacturing

Medical Technology

Aerospace Industry

Watch Industry

Railway Industry



holds tight precisely and rotates

WTO has developed toolholders with the new PTI interface and introduces a program for static tool holders and driven tools in the PTI-sizes. Based on the design of the interface polygon, the PTI shank and holder body form a precise unit with all the necessary elements for mechanical power transmission and media supply. The tool receivers of the precision toolholders are matched to the PTI sizes and make the outstanding performance of the PTI interface technologically feasible at the cutting edge.

Features of the driven PTI toolholders are the large drive shaft and the wedge-shaped coupling, transmitting 85 Nm torque (PTI65).


clamps powerful and accurate

The simply constructed, compact PTI clamping system from OTT-JAKOB clamps the tool shaft centrically with high precision over a 25° clamping shoulder. The high pull-in forces (75 kN with 35 Nm actuation torque at PTI65) give the PTI system a high bending load capacity and the polygon a tight fit for high torque transmission. The quick change system with manual operation on a screw can also be used for automatic clamping.

OTT-JAKOB completes the range of PTI products with the manufacturing of the polygon flanges. They are fitted with a friction-enhancing coating technology that provides power transfer from the polygon flange to the turret disk.


receives and drives

Sauter has designed the PTI radial turret with a front cover which allows easy mounting of the PTI clamping system. The compact design results in a width across flats of only 340 mm for PTI65 with a 12-fold turret disc.
The turret construction allows both the use of Speed-Drive® and Torque-Drive® technology. Despite the installation of the components in a confined space, a stable turret design has been created, realizing the performance of the PTI interface to 100%. All pathways required for the media supply are integrated as well. A strong drive for DTH (85 Nm) gives the PTI65 turret a unique milling performance.

In addition to the tool turret, the Sauter product range also includes toolholders and driven tools with a PTI interface.


turns faster and out-of-round

Weisser completes the team of the pti-working-group and is the first manufacturer to integrate a PTI turret in a turning centre. With a power of up to 80 kW and a torque of 1,250 Nm the vertical turning center Univertor AM-1 is a basis for a solid realization of the performance of the PTI65 interface. As a pioneer of out-of-round turning technology, Weisser is a manufacturer of PTI parts and a partner to the toolholder industry. Tool blanks with PTI shank as well as PTI receivers are produced on Weisser out-of-round turning centers.