Energy technology is undergoing global transformation. Rapidly expanding renewable energy and other, more volatile power generation plants require significantly higher flexibility of conventional plants. This has resulted in a number of new challenges for ventilation equipment, including:
An increased number of start and stop operations
Fewer full-load hours
Increased partial load operation
Lower exhaust gas temperatures due to residual heat utilization
Smaller gap to acid dew point
These factors cause an increased load on the systems which carries increased risk of corrosion during operation. This favors dew point corrosion, which can lead to total failure of fans and system components.
TLT-Turbo offers you a tailor-made solution for your plant by implementing effective corrosion protection measures to maintain uptime of your fans.
Efficient Protection against Corrosion
TLT-Turbo Corrosion Protection for fans includes two key actions: Preventing corrosion where possible and protecting components where corrosion cannot be prevented.
Avoiding corrosive conditions:
Preventing or reducing leakage of sealing air
Heating of fan components
Optimization of insulation
Use of corrosion resistant materials:
Weather resistant steel
Polymers and polymeric coatings
Ni-based coatings or base materials
In order to select the measures suitable to preventing and addressing corrosion on fans operating at your facility, TLT-Turbo conducts an individual corrosion risk assessment. This assessment is based on your operational and environmental conditions.
TLT-Turbo provides further support by conducting an analysis of your specific operating conditions, e.g. on a dew point measurement based on a plant inspection.
Contact TLT-Turbo to discuss your corrosion protection needs and to find the right service package to suit your on-going requirements.
Optimal Protection against Corrosion for Existing Plants
TLT-Turbo conducts corrosion risk assessments and implements suitable preventative measures when designing and manufacturing new fans. These measures can also be carried out when retrofitting existing plants or as part of preventative maintenance during a scheduled shutdown.
Contact your service representative or the TLT-Turbo Service Department for more information on conducting a tailored risk assessment at your facility.
In TLT-Turbo’s 145-year long history of developing centrifugal and axial fans, every fan has always been carefully evaluated through extensive testing before being deemed fit for application. These tests were greatly enhanced when computational testing became available. More recently, Computational Fluid Dynamics (CFD) simulation has greatly enhanced not only TLT-Turbo’s ability to conduct thorough product testing but has also created opportunities for developing new and improved fan types.
According to Sabine Groh, Product Manager for industry fans at TLT-Turbo in Bad Hersfeld, Germany, every TLT-Turbo fan type once was carefully evaluated and aerodynamically measured in aerodynamic test stands before being released for application in the customer’s operating environment. “The arrival of stronger computer performance has allowed us to utilize CFD simulation which has had a massive effect on our ability to develop new products and to improve existing fan types.”
Groh explains that CFD has numerous advantages, all of which have become integral to TLT-Turbo’s product development. One of the greatest advantages is that CFD has enhanced the understanding of flow phenomena more efficiently than empirical testing. By using CFD it is possible to zoom in and out of any area within the simulated geometry to determine most advantageous or disadvantageous parts or geometries. With examination options such as vectorplot, a detailed analysis of the direction within the flow is possible. Similarly, using streamlineplot or velocityplot provides a detailed view of irregularities or aerodynamic phenomena.
“This analysis helps us understand the parts or geometries that cause flow separations and turbulence which allows us to address these in our product design. We can use the CFD simulations for the development or improvement of different fan types, blade geometries or spiral casing for centrifugal fans,” says Groh.
Additionally, TLT-Turbo uses CFD to understand problems in the flow of a given customer application that might result in a loss of pressure, efficiency or untypical wear of parts exposed to the flow. This equips TLT-Turbo with the knowledge needed to carry out retrofitting and product enhancements to ensure improved future performance (see flow optimization use case below).
Flow Optimization Case Study
At a European power plant, a centrifugal fan was controlled by an inlet vane control. During operation, the blades of the vane were rattling after a while and needed repair. After replacement, the same blades were showing the same failure after some operation time. Figure 1 below shows the blade of the inlet vane control dismounted of the socket.
It was assumed that the flow was not homogeneous before it reached the inlet vane control blade, and the use of air guiding plates was considered to correct the flow. Through the use of CFD, this pattern could be more deeply investigated resulting in a superior solution.
Groh unpacks the process and explains how a better solution was found using CFD: “Each CFD requires four process steps. The first step is the creation of the 3D model of the geometry to be analyzed. The second step is discretization. This involves creating a three dimensional computational mesh in the model for the volume in which the medium flows. The third step is defining the boundary conditions for the simulation and as the fourth step, the simulation of the flow can be performed.”
In this specific instance, the ductwork ahead of the malfunctioning inlet vane control, the blades of the closure unit itself and the suction box behind the closure unit were all rendered in 3D models. Figure 2 below shows the geometry that was analyzed in detail in the computer model. The ductwork upstream and downstream was included to ensure the stability of the calculation in the simulation.
After meshing of the 3D model, a simulation was performed to determine the direction of the stream in the ducting ahead the inlet vane control in more detail. Figure 3 below shows the result of the simulation.
The simulation showed that a separation of the stream led to turbulence in the flow ahead of the closure unit. With the validated conclusions of the simulation, TLT-Turbo was able to investigate different proposed solutions to remedy the problem. Figure 4 below shows the streamline plots of these different solutions.
The conclusion was that a combination of two countermeasures in the ducting would be the most advantageous solution. So ahead of the closure unit, TLT-Turbo installed a suction nozzle that helped guide the incoming flow into the duct (see blue colored suction nozzle in Figure 5 below).
Behind the closure unit, TLT-Turbo also welded a split plate (blue colored plate in Figure 5) into the suction box to help guide the stream further into the inlet vane control ahead of the centrifugal fan.
The use of CFD has become an essential tool to TLT-Turbo for the development of new and more efficient fan types and blades. Instead of building numerous test models for each proposed blade or impeller type with subsequent aerodynamic model testing, different geometries can be compared in the CFD simulation directly. However, the value of CFD doesn´t end there. Increasingly, TLT-Turbo is also using CFD for aerodynamic optimization of flow in customer operating environments. That includes solving aerodynamic problems such as the example above, and for reducing wear, pressure loss or in general creating a more homogenous flow of the gas or air in the plant to maximize efficiency. Finally, the success of performance improvements as a result of replacing a fan in an existing casing, can be verified.
TLT-Turbo (GmbH), a leading supplier of ventilation equipment and systems has received a contract to provide longitudinal ventilation and escape route ventilation for the Baregg Tunnel project through a call for tender by the Swiss Federal Roads Office, ASTRA, based in Zofingen, Switzerland.
The scope of TLT-Turbo’s delivery on the project includes 16 stainless steel, dual-speed jet fans. The jet fans will meet the project’s temperature requirement of 250 °C/2 h. The contract also includes the supply of an extensive array of services including project management, documentation of performance and technical specifications, inspections, QA, testing, training of operating personnel and future maintenance. The order is currently being processed with completion of the installation expected by January 2024.
The Baregg tunnel and the Neuenhof covering are part of Switzerland’s N01 route, located between the exits and entrances of Baden-West and Wettingen. This section is known as one of the busiest sections of the Swiss national road network.
TLT-Turbo Head of Tunnel and Metro division, Jürgen Steltmann, said: “We scoped out this project by starting with a dimensional survey and inspection of the existing tunnel structure. This will be followed by planning, fabrication, factory tests and finally delivery and installation. We are confident that our approach will result in a ventilation solution that meets the requirements of the Baregg Tunnel project and ensures and safe environment for commuters.”
TLT-Turbo has over 100 years of experience in ventilation technology and has been developing, manufacturing, and constructing fans and ventilation systems for more than 40 years. This extensive experience has been consistently incorporated into the development of their tunnel ventilation systems.
According to Steltmann, to ensure a safe environment inside tunnels, TLT-Turbo’s foremost consideration is smoke. “In an emergency, smoke is one of the major hazards for people in an underground tunnel. Our ventilation systems provide clear visibility for escape routes. In case of fire, our Metro and Tunnel fans provide smoke free emergency exit routes.”
“Our other key considerations are quality, noise abatement and energy efficiency. Our fans are tested according to EN 12101-3 give tunnel operators peace of mind that they are receiving ventilation equipment that meets their specifications and is of the highest quality. From there, TLT-Turbo combines specially selected materials, highly heat-resistant motors and design precision to blend quality assurance with the highest economic efficiency,” Steltmann explains.
The aerodynamic features of TLT-Turbo’s Jet Fan range guarantee low power consumption and installation costs. They also help to keep the acoustic noise low. These fans may be used in tunnel sections as jet fans with free inlet and outlet and as axial fans in ducted installations. The success story of these fans started in the early 1970’s in the Alps and several important Alptransit-routes have been equipped with TLT-Turbo tunnel fans since then – including ventilation for the longest railway tunnel worldwide in the Gotthard Base Tunnel.
“Our track record combined with the fact we have well-trained, experienced staff who collaborate with leading international consultants to ensure that we meet expected international standards are what have made TLT-Turbo not just a supplier, but a preferred tunnel and metro ventilation partner renowned for redefining ventilation quality and performance,” Steltmann concludes.
During a short journey through the topics of fan aerodynamics, our TLT-Turbo fan experts pick you up at the aerodynamic basics and show you which improvements are possible through aerodynamic optimizations.
Starting with the basic understanding of volume flow and pressure rise, the journey continues via the origin and definition of the operating points to the various aerodynamic control types of fans in technical systems. You will understand the differences between fan types and the definition of efficiency. The journey ends with the identification of different optimization potentials of axial fans and how TLT-Turbo can support you in optimizing them.
Long lasting equipment is a must have for many industries due to the cost savings that can be derived from a longer lifespan on equipment and components. At their recently upgraded testing facility, TLT-Turbo GmbH are using a new research methodology based on dust particulate samples from steel manufacturing and processing facilities to determine the best solutions for minimizing wear on ventilation equipment based on the unique abrasive factors of this specific operating environment.
TLT Turbo GmbH is one of the world’s leading suppliers of heavy-duty centrifugal fans designed to operate efficiently in the most challenging applications. In the steel industry, these fans are exposed to high dust loads which causes them to prematurely fail due to faster wear. To determine the best solutions for slowing wear and tear, TLT-Turbo researchers procured original samples of the dust present at customer facilities and used these to investigate the reasons for wear and to determine remedies for reducing it.
Factors Affecting Wear on Fans
According to Sabine Groh, Product Manager for industry fans at TLT-Turbo in Bad Hersfeld, Germany, the main contributing factor to wear is the velocity of the abrasive particle. The erosion rate measurement below illustrates the exponential increase in the erosion rate based on velocity.
Groh states that additional factors include hardness, shape, number of particles and the angle between the particle jet and the surface of the fan component. The image below provides an indication of the typical shape of the abrasive particles used for research at TLT-Turbo’s newly upgraded particle jet test stand in Zweibrücken.
Finally, Groh argues that the particle size in comparison to the size and distribution of grain of the coating also plays a role. Figure 3 below shows a micrograph of a hardfacing layer suitable for abrasive dust with small particle sizes using a prototypical particle of 20µm. Figure 4 below shows a micrograph of a common Chrome Carbide hardfacing with a prototypical particle of 20µm as well. “In Figure 3 we can observe that the particle is less able to wash out the matrix because of the more homogenous distribution of the smaller grains. Figure 4 however shows that the large grain size and large distribution allows for easier erosion of the matrix,” Groh explains.
This proves that if the abrasive particles are small enough to impinge between the relatively hard grains of a hardfacing, then the matrix will be washed away and the grains will easily fall out afterwards. If the grains of the hardfacing are small enough with less space between them, matrix erosion will be prevented and the hardfacing will have a higher durability.
Emerging Research Trends
Over the last 10 years, TLT-Turbo performed thousands of particle jet tests to determine the erosion rate of different coatings and materials. To achieve a comparison between these coatings, a standardized test sand with a specific grain size distribution was utilized as abrasive material (as illustrated in Figure 2 above).
“TLT-Turbo has developed an extensive database on the erosion rates of different coatings and materials that have been exposed to the test sand at different angles and velocities. This database allows us to select promising solutions for customer’s abrasive problems,” says Groh.
TLT-Turbo has recently upgraded its test equipment and now has the capability to test using original dust supplied by the customer. Groh explains that this allows for the specific customer application, with all major influencing factors to be reproduced. In addition to the velocity and angle of the abrasive dust, a realistic indication of particle size, shape and hardness can now contribute to more accurate test results. “This means that we can provide a more definitive prediction of how a change in wear protection will affect the service lifespan of the equipment to each customer.”
Wear Test Case
The TLT-Turbo test lab asked a European customer to provide samples of dust from their facility for testing to determine how they could benefit from a coating solution suited to their specific application and environmental challenges.
From this specific dust particle sample, the grain size distribution was determined by performing a sieve analysis. Particle jet experiments were then performed on two preselected coatings. These experiments are in accordance with the norm DIN 50332 and were executed for three angles: 20°, 45° and 90°.
Figure 6 below illustrates the test results. The TLT W-104 coating was determined to be the best alternative for all impact angles, however the superiority of W-104 is best illustrated when used for the 90° impact angle.
In extremely abrasive applications, the choice of wear protection determines the service life of the fan. The upgraded test lab and particle jet test stand has afforded TLT-Turbo engineers a deeper understanding of the mechanisms behind wear and the effects of specialized solutions. This has led to new approaches in product advancement and development that are grounded in providing solutions that meet market requirements.
“The ability to use the original dust from the customer’s facility and duplicate the conditions such as velocity and the impingement angle on the coating, allows us to determine how all these factors including the shape, size and hardness of the abrasive particles affect erosion rates. TLT-Turbo has taken another great step forward in being able to reliably calculate the effect that changing in coatings to prevent wear will have on extending the service life of ventilation equipment. Establishing the best solution for wear related challenges now becomes a collaboration between TLT-Turbo and the customer.” Groh concludes.
We are excited to announce that an order has been secured for the supply of TLT-Turbo MVR fans from a globally renowned manufacturer for installation at an instant coffee production facility in Colombia.
Securing of this order comes after extensive engagement with this client over the past 4 years. The commitment and perseverance of the sales representatives involved, and the MVR team is highly commendable. Having a relationship with this client already in place means that this order may be the first step in a long-term strategic partnership.
The MVR fan that will be supplied is from the new Low Flow MVR Series. Having been in development for the past 18 months, this new addition to the MVR range is characterized by having a significantly smaller and more compact size while still delivering higher efficiencies. The development of this range is an exceptional achievement of our R&D department and product management team. Their delivery of this new range has allowed us to enter the small mass flows market which makes us more competitive.
The scope of work for the delivery, includes the supply of a 120kW drive power, approx. 4,500 kg/h mass flow, >83% efficiency high-speed MVR fan. The final installation site is an instant coffee production facility located in Medellin, Colombia.
The securing of this contract has already caught the attention of other global coffee producers and bodes well for the continued growth of our MVR department.
For more information on the TLT-Turbo MVR Range, click here.
Global ventilation fans and systems manufacturer, TLT-Turbo GmbH, has announced the launch of their new Low Flow MVR Fan Series. As a more compact alternative to TLT-Turbo’s existing larger-capacity MVR range, the new low flow series promises the same uncompromising efficiency that clients have come to expect from TLT-Turbo ventilation equipment.
Having been in development for the past 18 months, this new addition to the MVR (Mechanical Vapor Recompression) range is characterized by having a significantly smaller and more compact size while still delivering higher efficiencies.
In comparison to the existing MVR range, these fans are designed for lower mass flows at medium inlet temperatures. “The maximum speed is 6500 rpm. This limitation is mainly due to the fact that there are no faster rotating motors available in this range and for this application,” explains Mario Schmidt, Head of Business Segment Vapor Fans, TLT-Turbo. He adds that this range is ideally suited to industrial applications focused on the concentration of liquids.
The new Low Flow MVR series elegantly combines all the advantages and features of all other TLT-Turbo MVR series, including maintenance-free, long wear hybrid ceramic bearings and high efficiencies as well as speed-, temperature- and vibration monitoring. The fans are designed to achieve temperature increases up to 11°C while maintaining efficiencies of up to 83%.
“The development of this range is an exceptional achievement of our R&D department and product management team. The expansion of our current MVR offering has allowed us to enter the small mass flows market which makes us more competitive.”
The design of the new series was carefully considered, ensuring that all major customer and application requirements are met. Schmidt explains that these fans are made to deliver on performance. “The fans are available 24/7 with a wide range of operating points and high efficiencies of up to 83% depending on inlet temperatures and specified temperature increases. In addition to this, the fans are VFD controlled.”
The highest quality and safety standards are met by using only high quality and proven components. The fans’ monitoring devices are included with the installation, and all models are rigorously tested, and FEM calculated. Like their larger counterparts, the Low Flow MVR Series is manufactured using hybrid ceramic bearings that are lifetime greased and can be operated for up to 10 years without requiring maintenance. To enhance this benefit for clients, TLT-Turbo introduced an additional device to the fan’s design that allows for the bearing to be re-greased from the outside in order to further simplify maintenance and to increase the fans’ service life. “Maintenance is made even easier for our customers with the option for them to make use of our remote performance and maintenance checks.”
The new Low Flow MVR Series is manufactured at TLT-Turbo’s dedicated facility based in Germany and is available globally. An order has already been secured for the supply of TLT-Turbo Low Flow MVR fans from a globally renowned manufacturer for installation at an instant coffee production facility in Colombia. “The securing of this contract has already caught the attention of other global coffee producers and bodes well for the continued growth of our MVR division,” says Schmidt.
“TLT-Turbo is known for redefining ventilation, and this means we constantly strive to set new standards. With respect to all previous MVR series, TLT-Turbo is the first manufacturer to use hybrid ceramic bearings. In addition, all TLT-Turbo MVR fans are aerodynamically optimized and offer high efficiency. For further developments, new materials and manufacturing methods are also continually investigated to ensure that our customers benefit from the latest innovations. Our MVR range has been trusted for use in applications with stringent hygienic requirements such as highly polished impellers and housings. This, and all the other innovations showcased in the new series is the result of an almost 150-year track record in the design and production of industrial fans,” Schmidt concludes.
In 2020, TLT-Turbo GmbH in Zweibrücken has again donated EUR 2,500 for good causes. Part of the donation was handed over at Christmas, as we decided to abstain from gifts for business partners and instead donate this amount to various institutions.
A donation of EUR 350 is used to support the Diakonie Pfalz for their health retreat “Jugenddorf” (youth village). Every year, Diakonie Pfalz enables children and young people to take time out during the summer vacations. Unfortunately, in 2020 the camp could not take place due to the Corona pandemic.
The “Kinderschutzbund” (child protection agency) in Zweibrücken was supported with the purchase of a logo placement on their vehicle worth EUR 300. Their vehicle is used, for example, to distribute food to socially disadvantaged families.
A large part of the donation, EUR 600, went to “Sternenkinder” in Homburg. “Sternenkinder” is a self-help group for families who have lost one or more children before, during or after birth. The donation is used to buy fabrics and sew clothes and wrapping blankets for the deceased children.
The Diakonie Zweibrücken was supported with a donation of EUR 600 for the project “poverty due to Corona”. The Diakonie has set up a Corona relief fund to support people during the Corona crisis. However, this relief fund is very dependent on donations, which is why we wanted to make a special contribution here.
The remaining part of the donation, namely EUR 650 went to the Heinrich Kimmle Foundation Zweibrücken. It is an independent church foundation and supports people with impairments in the areas of work, living and pre-school as well as school education. There, the contribution is used as a transitional allowance to employment for people with disabilities, but also as financial support for obtaining a driver’s license.
No business has been left untouched by COVID-19. The global pandemic has created an unprecedented uncertainty for business operations as numerous federal and state governments instituted travel bans and national lockdowns to mitigate the spread of the virus. TLT-Turbo has taken numerous steps to ensure operational continuity for our clients’ ventilation equipment and have launched several new platforms for the delivery of field services. These new platforms will be showcases in an upcoming webinar available by invitation to TLT-Turbo clients in Germany.
Many of our clients run the world’s most essential businesses – mines, manufacturing plants, power generation plants and processing plants. Some are facing the challenges of operating a business through unprecedented shutdowns or feeling the effects of the COVID-19 pandemic. None of us could have foreseen the scenarios we are now facing – but at TLT-Turbo we have taken steps to ensure that we are facing them together. And whatever scenario your business finds itself in today, TLT-Turbo is here to help you keep your operations running.
As TLT-Turbo continues to navigate the changing tides posed by this pandemic, our priorities remain the same – to provide excellent, swift, and expert services.
We invite you to join us for a webinar session in which we present how TLT-Turbo is using innovation, creative thinking, and new tools to evolve and address customers’ critical needs now and in the future as we move towards the post-COVID-19 era.
Key discussion points will include:
TLT-Turbo Remote Service Support: Expert support to beat downtime is just one click away
TLT-Turbo’s Service Centre of Excellence: Bringing together our experts to help our customers succeed
TLT-Turbo Field Service Continuity Program: Maintain field service team availability under travel restrictions