Reliable remote-control of valves

The ends of the shaft feature robust stainless-steel pins that are permanently connected to the shaft and mounted in connecting sleeves so that they can rotate. One end is equipped with a grease nipple for lubrication if required, while the other end has an external thread that enables secure connection to brackets or bushings. This design facilitates installation and ensures high adaptability of the system. 

A wide range of adapters and components are available for connecting the flexible shaft to fittings and control elements, for mounting along the route, for torque transmission, and for wall or partition feed-throughs – including watertight versions. Some of these are available from stock as standard, while others can be customized to the specific requirements of the application in question. 

Advantages over alternative remote-control systems 

Compared to rigid shafts and hydraulic systems, the flexible shaft offers decisive advantages. It is maintenance-free and extremely durable: While rigid rods and joints are susceptible to dirt, corrosion, and malfunctions due to thermal expansion and contraction, the flexible shaft is reliably protected from external influences thanks on its closed design and continues to function perfectly even under extreme conditions. 

It is also highly resistant to thermal influences. While rigid systems can develop problems due to expansion or contraction when exposed to extreme temperature fluctuations, the flexible shaft remains fully functional even at extreme temperatures. Another advantage is that it does not require an external energy source. This makes it particularly suitable for locations without available auxiliary power, such as remote regions or emergency systems. 

Thanks to its mechanical mode of operation and robust design, the Flexible Shaft can also be used in potentially explosive atmospheres (ATEX). Since it uses neither electrical nor hydraulic components, there is no risk of sparking or leakage, which significantly increases safety in these environments. 

The installation of the flexible shaft is also particularly easy and flexible. While rigid rods often must be laboriously routed around obstacles, the flexible shaft can be easily bent and laid around corners, which significantly reduces installation effort and costs. Finally, thanks to high-quality, rust-free materials, it is highly resistant to corrosion and weathering, even in particularly aggressive environments such as salt water, chemicals, or extreme weather conditions. 

Areas of application 

The flexible shaft is used in numerous applications, especially where traditional systems reach their limits due to difficult environmental conditions or complex installation requirements. It is particularly suitable for offshore installations and shipbuilding, as it is corrosion-resistant and works reliably even under extreme conditions at sea. 

In the chemical and petrochemical industries, the flexible shaft impresses with its resistance to aggressive chemicals and its robust construction, making it ideal for remote actuation of valves in production plants. It also demonstrates its strengths in water and wastewater management: in damp and heavily polluted environments, such as sewage treatment plants or wastewater treatment plants, it guarantees long-term reliable operation and resistance to corrosion. 

The flexible shaft is also suitable for outdoor use or for underground installation. It can be easily laid in the ground, withstands weather conditions such as rain, snow, or heat, and works perfectly even in water or underwater. It can also be used safely in potentially explosive areas, such as ATEX-certified environments, as it does not generate sparks or other sources of danger. 

In addition, the flexible shaft offers an ideal solution for locations without available auxiliary power. In remote or self-sufficient applications, it operates completely manually, independently, and reliably, enabling safe remote operation of valves even where other systems reach their limits. 

Emergency manual operation of automated valves 

Another key application for flexible shafts is the emergency manual operation of automated valves. In systems that are normally controlled electrically, hydraulically, or pneumatically, it may be necessary to operate the valves manually in the event of a power failure. If the valve is installed in a hard-to-reach or potentially hazardous area, the flexible shaft enables safe remote control from a distance. This can be done from an adjacent room, behind a protective barrier, or from another safe location. This allows the system to be secured in a controlled manner without exposing the operating personnel to direct danger. Especially in safety-critical applications, the flexible shaft provides an additional level of safety to maintain operation even in the event of a power failure or to bring the plant into a controlled safety state. 

Functionality and variants 

The flexible shaft transmits the operator's rotational movement directly to the valve. Various operating units such as handwheels, cranks, or levers can be used and flexibly adapted to the conditions of the plant. For applications that require particularly high torques, a version with forged steel elements is available. This version enables the transmission of even higher torques and offers additional robustness for demanding operating conditions. 

Planning and application 

Planning the use of a flexible shaft requires careful adaptation to the specific application conditions. Factors such as minimum bending radii, the type of bushings, the mounting bracket, and the requirements for the transmissible torque must be considered. 

The required length of the shaft is determined based on the installation from the control station to the valve, considering possible obstacles and bends in the layout. The minimum radii for bends must not be exceeded to ensure optimum torque transmission. Depending on the distance of the remote control, the number and type of bends, and the type of valve, it may be necessary to use a gearbox to reduce the required torque. For particularly high torque transmission requirements, the reinforced version of the flexible shaft with forged steel elements is used. 

Special penetration sleeves are available for installations where the shaft must pass through walls or decks. These are also available in a watertight version and can be used in areas with special safety levels to ensure safe and reliable operation of the shaft. 

An online configurator at www.tramistec-configuration.net provides support during planning and enables the precise selection of the required components as well as coordination with the manufacturer or sales partner to achieve the optimum technical design for a particular arrangement. At the heart of the tool is a graphical representation for the manual remote operation of valves based on the flexible shaft. 

The components can be selected either against a blank background or on an uploaded image or drawing and inserted into the configuration using drag and drop. Available variants can be selected for the individual components, specific comments can be added, and components can be grouped together in user-defined groups. View drawings of the components with the most important main dimensions facilitate the visual coordination of the design with individual requirements. 

The configuration created can be saved locally as a project file for later editing or sending by email. This also makes it possible to create several alternative solutions for a single case by saving separate project files for each one. In addition, the configurations can be reviewed by ARMATUREN-WOLFF or the responsible sales partner to assess the consistency of the design and suggest alternative options if necessary. 

The online configurator also offers the option of generating documentation in PDF format, which contains an overview, a list of components with their properties, and drawings of individual parts. This means that the technical solution can also be reviewed and coordinated retrospectively without using the configurator. 

Maintenance and operation of the flexible shaft 

Thanks to its enclosed design, the flexible shaft is virtually maintenance-free. A hermetically sealed version can also be provided for special requirements. It is recommended that a functional test be carried out at regular intervals, whereby lubrication is easily performed via an integrated grease nipple, which ensures long-term functionality. Seals only need to be replaced if leaks occur at the penetration sleeves. 

Conclusion 

Compared to rigid rods and hydraulic systems, flexible shafts offer a significantly superior solution for remote actuation of valves. They combine flexibility, low maintenance, and resistance to dirt, moisture, and extreme temperatures. It is particularly advantageous for use in potentially explosive atmospheres, in locations without auxiliary power, and for emergency manual operation of automated valves. Thanks to its high adaptability, the ability to transmit high torques, and the support provided by the online configurator, it offers a customized and reliable solution for almost any application.