Self-contained linear
Self-contained linear actuator with fail-safe function CONTROL AND MEASUREMENT The new linear actuator from the German specialist, Voith, with safety features for valve control functions, combines the best of hydraulic and electromechanical technologies. The new Voith SelCon proves to be an excellent solution for applications in the gas and steam turbines. The Voith SelCon was primarily designed as a linear actuator with safety function for the valve controls of gas and steam turbines. It combines the advantages of hydraulic and electromechanical solutions. The hydraulics provides high force density and dynamics, the electromechanical side contributes simple, cost-effective system integration. Large effective forces up to 500 kN and ‘ATEX’ certification allow it to be used on turbines under virtually all conceivable ambient conditions. The hydraulic system of the SelCon is self-contained. An external hydraulic power pack with oil tank, control block and pipework is completely unnecessary. This reduces procurement costs by up to 35 % compared to a conventional solution. In addition, the system has a considerably higher operational reliability. External hydraulic disturbances such as pressure fluctuations, mismatched pipe diameters or negative pressure in the tank line are out of the question. The position is controlled by means of a servo pump according to the displacement principle. As a result, the actuator has a high degree of energy efficiency and the level of heat introduced into the integrated hydraulic system is low. The energy costs for operating the actuator are up to 50 % lower than for classic actuators using conventional valves and a hydraulic power pack. The control through the servo pump provides the same or even better dynamics and control response as comparable electromechanical actuators. This achieves stable processes with high product quality. The fail-safe function is implemented using an internal return spring. The trip time for the valve controls is typically less than 300 ms. This reduces the danger of direct and consequential damage considerably. The SelCon design is modular and usually compatible with existing hydraulic, electromechanical and pneumatic actuators. Integration into new systems and the modernization of existing systems can be accomplished in a cost-effective manner with minor planning effort. Various standardized communication interfaces and the use of real-time Ethernet protocols make the SelCon ready for Industry 4.0 (Internet of things) concepts. For example, intelligent process optimization, remote diagnostics and condition monitoring come to mind. Photograph: Voith GmbH www.voith.com About Voith Voith Turbo, a division of Voith GmbH, is a specialist for intelligent drive solutions and systems. Customers from highly diverse industries such as oil and gas, energy, mining and metal processing, mechanical engineering, ship technology, rail and commercial vehicles rely on advanced technologies from Voith Turbo. Voith sets standards in the energy, oil & gas, paper, raw materials and transportation & automotive sector. Founded in 1867, Voith employs more than 20,000 people, generates €4.3 billion in sales, operates in over 60 countries around the world and is one of the biggest family owned companies in Europe. (Excluding the discontinued Group Division Voith Industrial Services.) 44 MDA Technologies 1/2016
Product News Inductive sensors with an extended measurement range The new inductive sensors in the AlphaProx product family from Baumer are available in construction sizes of 6.5, M8 and M12. They offer a 50 % increase in measuring range of 3 mm or 6 mm. In this way the sensors can be installed with a greater safety clearance distance to the object and themselves protected from mechanical damages in critical applications e.g. measuring the bending deflection of a saw blade. The component sizes of 6.5 and M8 are only 30 mm long. Based on their short construction sizes this portfolio offers increased freedom of design in mechanical construction, as the sensors themselves can easily be built into narrow spaces and machine parts which are difficult to access. www.baumer.com Powerlink now runs in STW controls With the transfer of the real-time Powerlink Open Source Protocol to the ESX-3XL and ESX-3XM central controls as well as with their data management and telemetry module CONNEX-TC3G, STW shows a first possible access to the world of the industrial Ethernet. Powerlink is a real-time capability and hardware independent Open Source Protocol. It makes problem-free entry and conversion to the industrial Ethernet possible in construction machines and farm technology. As a solutions provider in these fields, STW’s goal is making new technologies available to its customers. For this reason this Open Source Protocol was transferred to the central controls, which are also configured for applications in safety-driven applications. Both controls distinguish themselves with their modularity and through their support of comfortable development environments for Codesys and the programming language “C“, as well as with their availability of well thought-out tool chains. www.sensor-technik.de/en The two-part brake linings in the KTR-Stop XL hydraulic brakes create a high contact ratio. The passive floating caliper brakes are manufactured completely from steel, weight ca. 1,100 kg and create clamping forces of up to 600 kN. The brake linings are available in the material finishes “organic” or “sinter metal“. In order to simplify changing the brake linings on the side that is often difficult to reach, KTR secured the linings to the fixed yoke side using magnets. To do this only the screws situated on the side were loosened, the Brake lining mounts are removed and the linings are pulled out to the side. The adjustment screws built into the brake pistons make quick settings and adjustments possible in high-pressure situations. www.ktr.com Passive floating caliper brakes with divided linings ATEX certified mechanical hand-held tachometer Rheintacho has received a Class I national technical approval for their ATEX version of mechanical hand-held tachometer. Tachometers are often used in fields in which the atmosphere is explosive due to dust particles or gases in it. The HTM was further developed and certified for this and for use in ATEX Zones 1 and 2, and for use in all groups of gases with temperature class T4. The certification approves use for applications in mining. HTM in both the ATEX model as well as also in the standard model measure the number of revolutions (rpm) and surface speeds with the help of special contact adapters. It fulfills the high demands of maintenance and calibration without battery power. www.rheintacho.de/en MDA Technologies 1/2016 45
