High Performance Marine Shafts for Sterngear assemblies

Teignbridge Propellers design and manufacture propeller shafts and couplings in various materials up to a maximum of 400mm diameter to suit customer’s requirements.
We machine the shafts in our custom-designed manufacturing facility using modern CNC lathes to ensure a highly accurate precision product.
All shafts are precision machined and straightened to ensure smooth operation and minimizing the potential for vibration.  Each shaft is individually inspected in accordance with our ISO9001:2015 procedures and issued with a quality control certificate.

The exclusive advantage of Temet 25

Our preferred material for marine shafts is Temet 25. Temet 25 is a high strength duplex stainless steel alloy with excellent corrosion fatigue strength and outstanding corrosion resistance. Temet 25 frequently results in a reduction in shaft diameter which reduces both cost and weight.

Temet 25 was developed by Teignbridge, after extensive research development and testing, when it was found that other high strength stainless steels suffered from corrosion defects and in particular “crevice corrosion”.

After an extensive period of research and development, and prolonged testing, with various materials, Temet 25 was shown to possess the outstanding corrosion fatigue strength and corrosion resistance. Fatigue testing was carried out, for Teignbridge by Exeter University laboratories. It was also carried out by Lloyds Register of shipping.
First introduced into the marine market by Teignbridge in 1990 it has become an industry standard, and the material of choice by the majority of boat builders.

Improved Shaft Design and Production

Teignbridge has recently invested in facilities, equipment and technology to improve shaft production.

The entire south wing of the extensive Newton Abbot facility has been redesigned and refitted to accommodate demand for increasing capacity for shaft production. The refit has also increased the length of shafts that Teignbridge can machine.  As a result we have five high accuracy CNC lathes than can machine shafts from 25mm to 400mm diameter and 12m in length.

In line with increased capacity, Teignbridge have also invested to improve shaft design calculations with the acquisition of state-of-the-art ShaftDesigner software.

An accurate representation of all components of the propulsion train, including engines, gearboxes, bearings and propellers, is created using details about each element. Because of the easy drag and drop function  all the propulsion train components are relatively fast to place, to speed up shaft line modelling. From an engineering point of view ShaftDesigner provides a useful tool to explore offsets to optimize the position of all propulsion train components based on acceptance criteria set by the user. This is done in order to, at an early stage, guarantee a good bearing load distribution and thus safe operation of the shaft line. Because ShaftDesigner can identify this issue in the ship’s design phase, possible time-consuming and costly (re-)alignment problems can be avoided. Also, at this early stage, with the various vibration modules, it is possible to calculate if a certain lay-out has the potential to create harmful vibrations and estimate possible alterations which could be necessary.

The theory and practical findings are continuously cross-validated, guaranteeing accurate and realistic results. In the development of ShaftDesigner there is also a close cooperation with classification societies and leading OEMs of various components of the propulsion train, in order to meet their needs and wishes.

Using this tool, we have the ability to analyse different operating conditions from ballast to laden, cold and warm engine and different states from uncoupled shaft, to fully assembled propulsion trains.

Please ask our Engineering Dept for assistance in undertaking whirling calculations using the ShaftDesigner software to ensure your project goes smoothly !