ISSN 0934-934 X K 30285 F VULKAN-VERLAG ESSEN / GERMANY Issue 2012/2013 http://www.industriearmaturen.de Simplify your actuators HOERBIGER Automatisierungstechnik GmbH Südliche Römerstraße 15 86972 Altenstadt, Deutschland Phone +49 (0)8861 221-0 / Fax +49 (0)8861 221-1305 E-Mail: info-haut@hoerbiger.com / www.hoerbiger.com
Compact, autonomous electrohydraulic valve actuators Hydraulic valve actuators have an ambivalent image on the market. On the one hand, system planners and valve manufacturers welcome their power density, high rigidity and easy integration of safety functions. On the other hand, users see considerable disadvantages in their installation size, the necessary piping and attendant problems in terms of reliability and maintenance. The new electrohydraulic compact power pack developed by HOERBIGER is a valve actuator that requires no piping or additional installation effort. This family of actuators blends the strengths of electric and hydraulic actuator technologies: high power density, easy integration of safety functions as well as high rigidity and intelligent functions MARCUS GRÖDL, BABAK FARROKHZAD THE TECHNOLOGY GAP Valve automation is used in systems to open and close pipelines as well as to control the flow rate of pressurized gases and liquids [1, 2]. Being the "muscle" in the control loop of industrial processes, automated valves are considered to be the most vital part [1, 2]. The use of hydraulic actuators is recommended for applications that require high forces or high torque, combined with an easy implementation of safety requirements and high control precision. While these actuators are valued for their high power density, robust design and easy implementation of failsafe functions, the literature and end users criticize the high installation costs, high power consumption, greater maintenance costs and leakage problems at the pipe connections. Moreover, these final control elements may be installed in areas that are prone to explosions only if each individual component is explosion-proof. This considerably increases the system and certification costs and poses another obstacle for the use of these actuators, in particular in the chemical, oil and gas industries as well as in power plants. Fig. 1: Electrohydraulic power unit for potentially explosive atmospheres 2
Fig. 2: A compact, self-contained valve actuator, which has an electric look and feel, drastically simplifies the construction, improves the reliability, and lowers the maintenance expense in the system Fig. 3: Electrohydraulic valve drive with steep thread actuator THE SOLUTION: COMPACT ELECTROHY- DRAULIC VALVE ACTUATORS THAT HAVE AN ELECTRIC LOOK AND FEEL A new generation overcomes these disadvantages of conventional hydraulic actuators and additionally has a compact, piping-free and modular design (Figure 1). The HOERBIGER concept is based on a hermetically sealed valve actuator, which allows for easy installation of an electric actuator and also exhibits the strengths of hydraulic control technology, such as high torque, easy-to-implement failsafe functions and more. It combines the advantages of electric and hydraulic actuator technologies. The result is a compact electrohydraulic actuator (Figure 2), which is <compact, < easy to install, <maintenance-free, < piping-free and reliable and has, < configurable failsafe functions. DESIGN AND COUPLING TO THE ACTUATOR In the design shown in Figure 3, the core component of the valve actuator is an electrohydraulic, explosionproof compact power unit that has the distinguishing features described above over classic hydraulic actuators. The compact power pack is mounted without any piping on a hydraulic steep thread actuator. To complete the system, the electronic controller can be mounted directly on the system or it can be integrated externally in an existing control cabinet. The electrohydraulic unit can be combined with the majority of commercially available hydraulic actuators. As a result, customers can continue to use their standard actuators without the need for the installation of new types of actuators. COMPACT DESIGN The valve actuator is designed for applications with torque up to 64 knm or 200 kn of force for linear drives. Measuring approximately 500 mm x 300 mm x 300 mm, the compact power pack is approximately four to five times smaller than an electrical final control element designed for similar torque (Figure 4). EASY INSTALLATION By reducing the interfaces to a mechanical interface to the valve and an electrical interface to the process control system, installation is easy and comparable to electric valve actuators, requiring no central hydraulic power unit with large tanks and accumulator elements and related piping. Given the easy installation, which requires only the supply of electrical power, the electrohydraulic compact power packs are particularly well-suited for the automation of remotely located valves. NO PIPING: HIGH RELIABILITY AND MAINTENANCE-FREE The piping-free design of the valve actuator (the modules of the hermetically sealed power unit are mounted directly on each other) assures that no leaks occur into the cover or outside the cover. The compact power pack is mounted to the actuator in the same manner 3
Fig. 4: The modular compact power pack can be easily connected to all common actuators and configured for all failsafe functions (Figure 5). This guarantees leakage-free and reliable operation. In addition, the encapsulated construction protects the components inside the valve actuator from harsh environmental factors such as corrosion. The problem of internal and external leakage typical of hydraulic control elements does not arise, and additionally the energy stored in the hydraulic accumulator is not lost over time. This guarantees a consistent position of the valve during operation Because of the decentralized concept, hydraulic energy is generated only on demand, which considerably lowers operating times and degrades the hydraulic fluid significantly less. This lower degradation allows for maintenance-free operation. HOERBIGER has successfully equipped more than 50,000 valves of ship manufacturers with compact electrohydraulic actuators, who are already benefitting from these advantages. Fig. 5: The piping-free design allows for maintenance-free operation 4
Fig. 6: Reduced installation costs of valves with safety functions in power plants for fossil fuels REFERENCE EXAMPLE: SIMPLIFIED INSTALLATION IN POWER PLANTS Conventionally designed electrohydraulic valve actuators often cannot be certified according to ATEX, or only with added expense. The users of such actuators therefore install these outside the explosion-prone area. This requires the installation of extensive piping, because the medium has to be conducted to the valve out of the explosionprone atmosphere and from the valve back into the hazardous explosive area. This problem is avoided with the explosion-proof compact HOERBIGER valve actuator. Because of the ATEX equipment and certification, the actuator can be installed directly in the environment that has the explosive atmosphere with the required safety functions (Figure 6). This has the advantage that the process of the customer's system can be optimally efficiently designed and no additional design solutions are required for the available valve actuators. Fig. 7: Reliable operation of valves in HCl pipeline: The considerably higher torque than that which is possible with electricity allows actuation of the valve even if it is stuck because of fouling. The hermetically sealed housing offers protection from corrosion due to salt mist. REFERENCE EXAMPLE: GREATER TORQUE RESERVE IN CHEMICAL PLANTS An encapsulated solution was developed for the HOERBIGER valve actuator, which is also available in an IP68 configuration. The power unit can therefore be employed in the chemical industry on production lines operating with corrosive substances. A typical example is the production of hydrochloric acid (Figure 7). During the production process, the valve becomes encrusted, requiring high breakaway torque to actuate it. This is where the force/ 5
torque performance of the compact electromechanical valve drives reaches its limits. While conventional hydraulic actuator systems would solve this problem, the corrosive environment to which the hydraulic components are exposed pose a serious threat to the reliability of the valves in the medium term. The encapsulated design of the HOERBIGER valve actuator, which protects the components and the power unit, makes it possible to use the valve actuator in corrosive environments and achieve high torque. As a result, sufficient power reserves are available for the breakaway torque. Other applications in which the HOERBIGER valve actuator can be employed include: < Pipelines for oil and gas: emission-free and simpler implementation of failsafe functions in on/off valves as compared to electric final control elements < Discharge and accumulator applications: greater rigidity than pneumatic final control elements, and therefore higher positioning precision allowing better control of the quantities to be accumulated or discharged < Pumping stations: on/off valves with greater force or higher torque < Power plants: control valves for the supply of steam to turbines for installation in atmospheres prone to explosions LITERATURE [1] Baumann, H.-D.: Control Valve Primer: A User s Guide, 4 th edition., Instrumentation, Systems, and Automation Society, Research Triangle Park, NC, USA, 2009 [2] Ignatowitz, E.: Chemietechnik, 9th edition., Verlag Europa Lehrmittel, Haan, Germany, 2009 THE AUTHORS MARCUS GRÖDL HOERBIGER Automatisierungstechnik GmbH 86972 Altenstadt Germany +49 8861 221 1622 marcus.groedl@hoerbiger.com DR.-ING. BABAK FARROKHZAD HOERBIGER Automatisierungstechnik Holding GmbH, Tech Gate Stuttgart 70563 Stuttgart Germany +49 711 128505125 babak.farrokhzad@hoerbiger.com 6
HOERBIGER Automation Technology Company name/location: Management: History: Group: Cooperation: HOERBIGER Automatisierungstechnik GmbH, 86972 Altenstadt, Germany Norbert Gauß The catalyst that triggered the success story of HOERBIGER was the patent in 1894 for the steel plate valve invented by Hanns Hörbiger. Since 1972, Automation Technology has laid the technological foundation for piezo technology for smart positioners and compact hydraulic power packs for use in valve actuation. Proceeding from this technological basis, in 2009 the innovative electrohydraulic, ATEX-approved valve actuator for use in the process and power plant industries was unveiled. The HOERBIGER Group has approximately 6,700 employees and 1 billion in sales and is a global leader in the fields of compression technology, automation technology, and drive technology. The focal points of its business activities include key components and services for compressors, gas-powered engines, and turbomachinery, hydraulic systems and piezo technology for manufacturing and process automation, as well as components and systems for shift and clutch operations in drive trains. The HOERBIGER Research Institute for Smart Actuators at Johannes Kepler University in Linz, Austria, explores new technologies for smart actuators. In addition, HOERBIGER maintains cooperative relationships with leading universities in the fields of fluidics and metal forming technology. Employees: 309 (December 2010) Export share: approx. 75% Product spectrum: Production: Competitive advantages: Certification: Service options: Web address: Contact: HOERBIGER Automation Technology is a leading provider of smart actuators in demanding niche markets: Smart actuators for valves: electrohydraulic and piezo-pneumatic Smart actuators for machine tools Hydraulic systems for specialty applications, e.g. mobile operating tables HOERBIGER manufactures all essential components and systems in-house. These include components that constitute the actuators unique selling propositions: piezo-pneumatic pilot valves and ATEX pneumatic valves, compact electrohydraulic power packs, proportional and control valves. In addition, HOERBIGER produces hydraulic control blocks, power units and cylinders. In Automation Technology, HOERBIGER focuses on customer-oriented solutions based on reliable, performance-defining, simple, and energy-efficient actuators. These actuators offer clear unique selling propositions and blend the benefits of fluidic actuators with those of electrical systems. The simple design increases reliability. Fewer interfaces allow easy installation. High technical performance results in high energy efficiency. ISO 9001/2008, ATEX certification in accordance with directive 94/9/EC, pressure equipment certified according to directive 97/23/EC. As a partner to the oil, gas, and process industries, HOERBIGER has been internationally represented for years with a total of 180 production plants and service companies. www.hoerbiger.com David Penny, Head of Global Sales, Strategic Business Unit Automation Technology, +49 162 277 7551, david.penny@hoerbiger.com 7
HOERBIGER - We set standards Wherever we operate, we set standards with performance-defining components, system solutions, and services - and thereby increase the efficiency of the capital investment in premium capital goods. HOERBIGER Automation Technology is a business unit of HOERBIGER Holding AG, Zug / Switzerland. HOERBIGER is active throughout the world as a leading player in the fields of compression technology, automation technology and drive technology. In 2010, its 6,700 employees achieved sales of 950 million Euro. The focal points of its business activities include key components and services for compressors, gas engines and turbomachines, hydraulic systems and piezo technology for vehicles and machine tools, as well as components and systems for shift and clutch operations in vehicle drive trains of all kinds. Through innovations in attractive technological niche markets, the HOERBIGER Group sets standards and delivers cutting-edge solutions for the benefit of its customers. HOERBIGER AUTOMATISIERUNGSTECHNIK GmbH Südliche Römerstraße 15 86972 Altenstadt, Deutschland Phone: +49 (0)8861 221-0 Fax: +49 (0)8861 221-1305 E-Mail: info-haut@hoerbiger.com www.hoerbiger.com