Markus Jennebach
Head of Business Unit Nuclear Industries and member of the board,
Bopp & Reuther Sicherheits- und Regelarmaturen GmbH, Germany
Paul Schaller
Sempell Aktiengesellschaft Sales Manager, nuclear, for Russia,
Ukraine and NIS
What are the major challenges faced for valves in the Nuclear sector?
Markus Jennebach: Valve designs have to be adapted for the new “generation 3” reactor types like AREVAS EPR, KHNP’s AP 1400 or Russian VVR 1200. A close cooperation between the valve manufacturer, design institutes and operators will play an important role in the success of future projects.
Paul Schaller: Safety and reliability first. Valve and pump failure has played a part in several incidents at nuclear power stations, most notably in the Three Mile Island accident. Such failures continue to trigger shutdowns, headlines and enquiries.
The operators desire to improve enables manufacturers like SEMPELL to come up with safer, more reliable valves. SEMPELL is responding to the need for increased safety and reliability. Leak tightness is another absolute must.
How do you see this sector developing in the coming decade?
Markus Jennebach: More then 100 new reactors are planned to be built within the next 20 years worldwide. Russia is one of the biggest markets in this sector. The valve manufacturers operating in this market are increasing their capacity to be able to meet the imminent demand of the nuclear market.
Bopp & Reuther has doubled the orders received and turnover over the last two years.
Paul Schaller: Demand for energy consumption is increasing world-wide, especially in China and the rest of Asia. A number of countries are planning or thinking of building their first nuclear power capacity (Turkey, Thailand, Egypt, Libya, Morocco, Algeria, Tunisia, Australia, Indonesia, Poland), while others are reconsidering or reversing their phase-out policies (the Netherlands, Argentina). All the recent talk about a “nuclear renaissance” applies only to those countries that soft-pedalled nuclear power in recent years. In the Asia Pacific area, however, nuclear power never went away. When nuclear power in the West stagnated, construction of new power stations continued in China, Japan and South Korea. China is planning to double its nuclear capacity from its current 2 per cent of electricity to 4 per cent by 2020. When it comes to reactor type, the Chinese are hedging their bets, ordering designs from Westinghouse, AREVA and Canada’s AECL, while also developing an indigenous form of pebble bed reactor. Next to China, India is Asia’s largest consumer of energy. Russia, which has already built two reactors in India, has agreed to build four more at India’s Kudankulam power plant. These are NPP-92 water-cooled reactors. India also employs PHWRs similar to the CANDU design and is planning three EPRs. Meanwhile Japan and South Korea are each developing their own reactor designs. Toshiba is developing a new BWR to set alongside the well established PWR it inherited with Westinghouse, while South Korea has come up with the APR1400, the first example of which will be commissioned in 2013 or 2014.
Europe and the CIS countries are the two other regions where nuclear power can be expected to grow significantly. France, which is already 75%-reliant on nuclear for its electricity, builds a reactor at Flamanville in Normandy and is also hosting ITER.
In Europe the overall outlook is mixed: In Finland AREVA’s Olkiluoto 3 EPR is under construction. Other countries proposing, planning or building nuclear facilities include the Netherlands, Romania, Slovakia, Slovenia and the Czech Republic. In Germany the moratorium on new construction still holds.
Major changes have been seen in the structure of the Russian nuclear sector together with ambitious plans for reactor construction at home, export plans to other markets and involvement in many international initiatives within the fuel cycle. In 2006 it was decided to create a single vertically-integrated state holding company for Russia’s nuclear power sector. On domestic power generation, it is important to note that Russian demand is rising strongly after more than a decade of stagnation. The most important point, however, is that it is now clearly Russian policy to export gas rather than use it for domestic power generation. In September 2006, a target of nuclear providing 23% of electricity by 2020 was announced. These plans are undoubtedly ambitious. Nevertheless, the problem concerning finance for reactors in Russia, which has constrained plans for much of the period since 1990, would appear to be largely over. Difficulties in the future are likely to be similar to that elsewhere in the world, such as the availability of enough capacity to manufacture the major reactor components in sufficient volume.
Valves play a key role in the day to day operations of NPP’s. What specific solutions do you have for the Russian Nuclear Power Sector?
Markus Jennebach: Bopp & Reuther offers a number of valves ideally suited to the Russian Nuclear Market. Core-products include Safety Valves, Control Valves and Gate Valves for various applications. Bopp & Reuther has extensive experience in engineering and supplying various types of valves to Russian Nuclear Power Plants since 1982. Applications include Main Steam Safety Valves as well as Pressurizer Safety Valves; these installations have provided decades of trouble free service.
Paul Schaller: SEMPELL benefits from more than 135 years of experience and delivers control, safety relief and isolation valves to conventional and nuclear power plants. Since the beginning of the nuclear power industry in the early sixties, SEMPELL has developed and delivered special valves. For this purpose the close and trusting cooperation with the engineering companies and end users has been a mandatory requirement. Till today a large number of standard and special valves have been delivered to all known reactor types. Some examples for the Russian NPP’s are:
» Main-Steam Isolation Valves – In boiling water and pressure water reactors quick-closing valves are installed for quick and safe isolation of the main steam pipe line. Stroke times are between 1–5 sec. The body type is selected according to the pipe layout. The most typical body types are straight and angle type.
» Safety Valves for Main Steam and Pressurizer – Safety valves are installed to avoid inadmissible pressure increase in a system. Depending on the engineering company and the required specifications
– spring loaded safety valves or
– pilot operated safety valves according to the system medium principle are installed. SEMPELL has concentrated with the operated safety valves Type VS99 on a solution with pilot operation according the pressure release principle.
» Gate Valves – In the nuclear industry gate valves are often used instead of globe valves, because of the low pressure loss. The SEMPELL wedge gate valve wedges only in the final position, thus protecting the seat surfaces, as the guidance in the body avoid a permanent contact on the seat surfaces during stroking. At low pressures additional compressing forces on the seat are created by the wedging. If gate valves, mainly with electric actuators, are supposed to fulfill extra tasks, special designs have been developed, optional as wedge gate or parallel slide valves. Such special tasks are the so called malfunction and blow-down ability. In these cases tests and calculations have to prove that the design fulfills the function and tightness after actuation at a complete pipe break and not correct shut down of the actuator. The ability of the SEMPELL-design has been demonstrated by blow-down tests.
Nuclear class valves must control critical flow points often over a long time period; what specific valves do you supply in this area and what average run life do they have?
Markus Jennebach: Bopp & Reuther is specialized in Safety Valves. The first Steam generator Safety Valves were delivered to NPP Novovoronezh 1982. The Valves are in operation today, providing safety to the system and giving trouble free operation and customer satisfaction.
Paul Schaller: Most Generation II reactors were built for a life span of 40 years.
Future reactors will burn at higher temperatures than current ones and will require metals that can withstand temperatures of around 1000 degrees C. Several metals are being researched and tested both for their heat resistance properties and a number of other criteria: tensile creep and creep – fatigue properties, thermal conductivity and expansion. These metals in question will also have to withstand severe corrosion environments and to be able to last for 60 years. SEMPELL is a leading valves manufacturer even in this field, already applying next generation materials like Alloy 617 for supercritical conventional applications.
Many NPP’s in Russia are nearing full maturity and plant managers and engineers will look to companies with a long history in this area when they come to upgrading and replacing parts. Briefly describe your history in this sector and ambitions for the Russian market.
Markus Jennebach: Bopp & Reuther was founded 1872 in Mannheim, Germany. The company has a long tradition and experience in designing and manufacturing various types of valves for a wide range of applications. From the very birth of the nuclear power industry in the 60s, Bopp & Reuther has played an active role in engineering and manufacturing various types of valves accompanied by a close cooperation with design institutes and operators to ensure project success and trouble free operation. The installations are backed up by an extensive service department to ensure trouble free operation, the necessary spares availability is guaranteed for more 30 years after the installation with close engineering consultation and possible upgrades adding to customer satisfaction.
This close relationship and contact with existing customers is often extended with consultation on modernization of existing installations. For this purpose our Moscow branch office and the headquarters staff in Mannheim have been enlarged to meet the market demands and providing the renowned Bopp & Reuther customer service and support.
Paul Schaller: Built for a life span of 40 years for the generation II reactors technological improvements mean that these reactors can be upgraded to be safer and more efficient than they were first built. In Russia a round of license renewals is therefore under way that will extend the life span of generation II reactors.
The complete expertise of SEMPELL AG, as well as all technical documents for the valves previously delivered by Babcock, is available to benefit the customers. Therefore, the SEMPELL Armaturen-Service is predestined to supply its customers not only with the required spare parts, but corresponding technical advice for these products as well.
The goal for valve manufacturers is to maximize power production while ensuring zero exposure to radiation. How do your valves guarantee these two important targets?
Markus Jennebach: The key words are; reliability, extended operation between maintenance, low maintenance costs, excellent sealing properties and high quality standards.
To ensure profitable operation and while reducing the effects of exposure to radiation, strict manufacturing standards must be applied and adhered to.
Bopp&Reuther products have long maintenance intervals and the down time required for maintenance is very low.
The sealing properties are excellent and extend over the entire life of the valves providing trouble free efficient performance while retaining pressure setting accuracy.
Paul Schaller: No comment.
Safety and reliability are paramount in this sector. What are the current test standards that are required, and is independent testing needed or can testing be performed by the manufacturer?
Markus Jennebach: No comment.
Paul Schaller: The flow behavior of gas and liquid properties are analytically and experimentally investigated.
A highly capable software package is available at SEMPELL for flow analysis, which may also be used for static and dynamic FEM-analyses. A laboratory with various capable air and water test equipment exists for experimental flow investigations.
A specialty at SEMPELL is a steam test facility, which can operate at steam conditions of a primary circuit of a pressurizer water reactor at 175 bar and 350°C. The electrically heated steam generator produces 1 t of steam / h under the above mentioned conditions. Located behind the steam generator is a pressure vessel with 3 test rigs. Tests within the laboratory could eliminate a part of the hot commissioning on site.
The qualification of safety related valves for NPPs is hardly impossible without experiments especially under consideration of anticipated accidents. One anticipated accident is the break of a big pipeline, e.g. the main steam line. Only out-of-pile but full scale experiments can provide certainty that the Main Steam Isolation Valve will reliable close under pipe break conditions. Such a verification test must model system parameters such as decreasing steam generator pressure, flashing of the steam generator water inventory, increase back pressure and the flow rate. These kind of tests are carried out at special valve testing facilities in the, e.g. at the AREVA Large Valve Test Facility GAP, Technical Center Karlstein. Moreover, such qualifications, although expensive, have the advantage that the valve malfunction risks are taken out of the start-up phase of the power plant and transferred to the pre-operational laboratory tests.
The most common regulations in this field are ASME QME-1 and IEEE-382.
Are there any specific requirements or adaptations needed for the Russian Market place?
Markus Jennebach: Test standards depend on the design requirements specified by the customer and the safety class of the product.
In general it has to be distinguished between a general design approval and production tests.
Test and quality standards depend on the nuclear code which is applied and design requirements specified by the customer. In addition to this, the individual safety and quality classification of the valve further defines the test procedure which has to be adhered to.
The designs of Bopp &Reuther products are certified according several international standards (for. eg. National Board Capacity Certification for Nuclear valves according ASME Sec. III or German TÜV type approval). So the design of our products are proven and tested by independent organizations based on national and international requirements. Also some of our products are tested according special customer requirements i.e. QME-1 qualification for Main Steam Safety Valve or IEEE qualification of limit switches and electric motors.
The majority of the required production tests can be carried out at Bopp&Reuther’s manufacturing facility using certified internal test rigs.
An adaptation to the Russian nuclear norms and regulations (eg. PNAEG, OTT…) is required for the Russian Market.
Paul Schaller: SEMPELL is aware of the standards and regulations applicable for nuclear valves in the Russian Federation. The Russian norms and standards are sometimes inconsistent and out of date. Nevertheless SEMPELL successful participated in projects for NPP-modernization and new construction sites acting based on the highest safety standards and requirements.
The more challenging issue in the latest times for our company in the Russian market is the unreasonable low budget policy of the design institutes responsible for the turn-key construction of the NPPs in Russia and where the price seem to be the only relevant indicators. On our point of view this is undermining priorities like safety
and reliability.
Markus Jennebach graduated as an engineer from the Giessen University of applied Sciences in 1988 with a degree dissertation in Atomic Research and Development and joined Bopp & Reuther SR GmbH last year. Over the years he has held various domestic and international positions in sales, operations and marketing focused on enviromental technologies. For the last ten years he has been focused solely on Valves for nuclear applications.
Paul Schaller graduated with a degree in International management and business law before joining Burgmann Ukraine to be trained on behalf of the German Federal Ministry for Education and Research. After working with Burgmann Ukraine, Energodar, for 2 years and being appointed director, he joined Sempell Aktiengesellschaft in his current position of Sales Manager, nuclear, for Russia, Ukraine and NIS.
