Multi-turn gearboxes Spur gearboxes GSTI 25.1 – GSTI 40.1 for use in nuclear power plants Outside and Inside Containment Torques up to 16,000 Nm Product description

Applications AUMA GSTI multi-turn gearboxes are used in nuclear power plants for the automation of gate valves and globe valves with high torque requirements. For this purpose they are combined with an AUMA SAN or SAI actuator or with any other multi-turn actuator which has been qualified accordingly. The gearboxes are certified according to IEEE 382-1996. They are qualified for use in outside and inside containment applications. The GSTI gearbox range is ideally adapted to AUMA SAN and SAI multi-turn actuators. By combining the multi-turn actuators with a GSTI gearbox, the maximum torque range...

Quality is not just a matter of trust 14 Solutions for a world in motion This brochure will provide both the beginner and the expert with an overview of the functions and applications of AUMA GSTI multi-turn gearboxes. It can be used as the basis to determine whether a device is suitable for the chosen application. For detailed product selection refer to the separate data sheets and price lists. On request, AUMA engineers within field service and within our subsidiaries can help you find the correct device for the application. Since the mid-1970s, AUMA has been producing devices for the use in...

Modular design/versions Modular concept – different applications Valves in nuclear power plants are used in areas with different safety relevance (outside containment and inside containment) but also in conventional areas. They are available in many designs and different sizes. Gate valves and globe valves with diameters ranging from a few centimetres to several metres are to be opened and closed electrically. AUMA meets the various requirements with their modular product range. GST and GSTI multi-turn gearboxes are central elements of this product range. The GST range is suitable for use in...

[1] [2] [3] [4] [1] GSTI spur gearboxes The designation spur gearbox refers to the gearbox design principle. [2] Multi-turn actuator/spur gearbox combinations SAN/GSTI Torques up to 16,000 Nm Multi-turn actuators SAN 07.1 – SAN 25.1 are approved for outside containment use. The combination of SAN multi-turn actuators and GSTI gearboxes are therefore suitable for use outside containment. The multi-turn actuator is mounted with a screw connection to the flange for actuator of the gearbox which can easily be removed for maintenance purposes. The flange connection between multi-turn actuator and...

Summary of applications, functions, and equipment Standard ● Option ■ GSTI 25.1 – GSTI 40.1 Page Applications/duty types Open-close duty ● 4 Positioning duty ● 4 Enclosure protection IP 68-6 ● 8 Corrosion protection KI ● 9 Resistant to DBE temperature ● 9 Vibration resistance ● 9 Radiation resistance ● 8 ● 10 Output drive types B, B1 ● 11 A, B2, B3, B4, E ■ 11 Special output drives ■ 11 Service conditions Functions Reduction of input torques Valve attachment according to EN ISO 5210/DIN 3210 6 |

Design principle [5] [6] [1] [2] [1] Housing The housing is made of spheroidal cast iron GJS-400-15. This material is resistant to extreme vibrations caused e.g. by an earthquake or an airplane crash. [2] Free shaft end In case of unfavourable space conditions where direct mounting of the multi-turn actuator is not possible, the input torque may also be supplied via a shaft with universal joint at the free shaft end. [3] [3] Spur gear This gear type is easy to install and of robust and cost-effective design. The reduction ratio extends the torque range of the multi-turn actuator. You have to...

Service conditions Devices for use in nuclear power plants have to remain fully operable, not only under normal operation, but also under DBE conditions. During comprehensive testing the devices have to withstand the most extreme loads and conditions. Qualification of the gearboxes in accordance with IEEE 382-1996 The following test was performed and passed. Functional tests are performed between the individual test stages. Test steps Thermal ageing 700 h at 100 °C Mechanical ageing OPEN-CLOSE duty 2,000 cycles with a load profile in accordance with KTA 3504-9/88 Normal radiation ageing test...

Enclosure protection Ambient temperatures IP 68-6 The specified values are also valid for high humidity (> 95 %). According to EN 60 529, the conditions to fulfil enclosure protection IP 68 are not defined. In the basic version the GSTI gearboxes are supplied in enclosure protection IP 68-6. IP 68-6 means protection against ingress of water during submersion up 6 m head of water. Normal operation ■ – 25 °C to + 80 °C DBE conditions ■ up to + 185 °C for a short period Corrosion protection/Colour Corrosion protection KI This corrosion protection was specially developed for AUMA devices used in...

Functions The basic function of the GSTI multi-turn gearboxes is described as follows: Decrease of the input torque required at the valve by means of a reduction ratio. Reduction of input torques The demands on the device are high and clearly stipulated in the corresponding standards, e.g. IEEE 382. The gearboxes have to operate reliably over the entire planned operation time of the power plant and even under DBE conditions. The maximum torque of the SAN multi-turn actuator range is 1,600 Nm and of the SAI range, 1,000 Nm. However, this is not sufficient for some valves. In these cases, the actuators...

Valve attachment The gearboxes are mounted to the valve using a mounting flange standardised according to EN ISO 5210 or DIN 3210. [1] The output drive types are also manufactured according to these standards. They establish the mechanical connection between the output drive of the gearbox and the valve stem or the valve shaft. The torque is transmitted from the gearbox to the valve using this connection. There are various output drive types available for different valve types. [2] [3] [4] [1] Output drive types B1, B2 (EN ISO 5210), or B (DIN 3210) This output drive is integrated into the hollow...