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Exhaust silencer CHP (Combined heat and power plants)

NovaNox® exhaust silencers are also used in combined heat and power plants to reduce noise emissions. Combined heat and power plants generate heat and electricity by burning fuel. It is usually fired by diesel or gas engines and thus has a higher efficiency than comparable plants. Areas of application for CHP units are, for example, agricultural crops, the food industry or industrial plants.

The NovaNox® exhaust silencers CHP are individually manufactured and directly adapted to your specific requirement profile. They absorb the sound waves of medium and high frequencies and thus effectively attenuate noise emissions. In addition, the installation of resonance chambers filters out the low-frequency humming typical of CHP units.

Absorption silencers and reflection silencers as well as combination silencers can be used for this sound insulation in CHP units. The NovaNox® absorption silencers are particularly useful for reducing the sound level of medium and high frequencies. Furthermore, these silencers generate hardly any pressure loss in the system. The reflective silencers, on the other hand, are particularly effective at low frequencies. They also impress with their durability and unrestricted effect.

The various silencers are installed individually or as a combination silencer, depending on the plant. The NovaNox® team is at your side for individual planning and helps you to develop the perfect exhaust silencer CHP for your requirement profile.

Exhaust silencer CHP (Combined heat and power plants)

Structure of the NovaNox® absorption silencer BHKW

The NovaNox® absorption silencers CHP are custom-made for your specific installation situation. The interior of the silencer consists of porous material. Usually rock wool or glass wool is used as insulation material. This absorbs the sound generated and converts it into heat. A stainless steel sieve tube passes through the insulating material, which is encased in stainless steel mesh and releases the sound.

NovaNox® absorption silencers are installed at medium and high frequencies. In combined heat and power plants, they are mainly installed in combination with reflective silencers to optimally reduce noise emissions.

Structure of the NovaNox® absorption silencer BHKW

Structure of the NovaNox® Reflective Silencers CHP

The NovaNox® reflection silencers CHP, or also called chamber silencers, use a completely different method of sound attenuation than the absorption silencers. The name is derived from the reflection chambers at the rear end of the silencer. However, the general design is similar to that of absorption silencers. A stainless steel sieve tube is also connected to the silencer body, which is wrapped in stainless steel mesh and embedded in insulating material. As the name "chamber silencer" suggests, however, reflective silencers contain several chambers. These chambers serve the principle of sound reflection and sound wave superposition. Here, the sound passes through the interior of the chambers several times, resulting in the sound pressure amplitude and reducing the sound pressure peaks. Baffle walls, cross-sectional expansions and also cross-sectional constrictions enable optimum reflection and the resulting reduction of noise emissions. NovaNox® reflective silencers BHKW are used to reduce noise emissions at low frequencies. They are preferably installed in combined heat and power plants in combination with absorption silencers to ensure an optimal result.

Structure of the NovaNox® Reflective Silencers CHP

Structure of the NovaNox® combination silencers CHP

The NovaNox® combination silencers CHP are used to cover a particularly wide range of frequencies. They are a combination of absorption silencers and reflection silencers. Here, they can be placed separately in the plant as middle and end silencers, or they can be installed in a single silencer.

In order to optimally reduce the noise emissions of your CHP unit, the NovaNox team with its many years of expertise is available to you at any time. Book your non-binding consultation with one of our employees at the bottom of the page today.

Structure of the NovaNox® combination silencers CHP

Customized production

Thanks to our many years of experience in the realization of custom-made silencers, we develop and produce individual exhaust silencers CHP for manufacturers of machinery, equipment and vehicle technology, industrial plants, agricultural crops or industrial plants.
In order to use the given installation space effectively and optimally, we take over the complete planning of the dimensions, the arrangement and also the materials. Through this precise coordination, the performance results of the NovaNox® exhaust silencers CHP are positively influenced and the sound is optimally reduced. Furthermore, by selecting the optimal materials, the performance of your NovaNox® exhaust silencer CHP is maximized.

The NovaNox® exhaust silencers CHP are made of tested and high-quality steel or stainless steel. The insulating material inside consists exclusively of first-class glass fiber wool, stainless steel wool or rock wool.

Furthermore, it is possible to use non-hygroscopic insulation materials in case of high condensate occurrence. This prevents moisture from being trapped, thus avoiding permanent condensation inside the exhaust silencer. The prevention of condensate formation in turn maintains the performance level of the silencer and significantly increases its service life.

If you have any further questions about NovaNox® exhaust silencers CHP, book your personal and non-binding consultation with our staff.

Customized production

Manufacturing process

Manual welding
With the help of our trained personnel and many years of know-how in welding, we manufacture not only in the automated welding process. We also manufacture hand-welded exhaust silencers. The manual welding process allows us to offer you a cost-effective alternative with fast turnaround times. It is mainly used for custom-made products as well as small and medium-sized series. The hand-welded exhaust silencers are manufactured on modern welding tables. Due to our own fixture construction we can guarantee the dimensional accuracy. In addition, repeatability can be guaranteed at all times, even with high tolerances.

Automated welding
We use state-of-the-art welding robots in our automated welding process. Automating these manufacturing processes increases the speed and efficiency of the process. As a result, we ensure consistent quality at all times when manufacturing high demand products. In addition, the automated welding process offers extremely high precision. As a result, even very complex exhaust silencers CHP with high tolerance requirements can be realized.

Manufacturing process

Surface treatments

The NovaNox® surface treatments increase both the service life and safety as well as the appearance of the exhaust silencers CHP. Through the surface treatment we can offer you a durable corrosion-free, safe and solid surface of your exhaust silencers. With the help of our own powder coating and painting facility, the surfaces can be presented in all RAL colors quickly and with high quality. In addition, we offer heat-resistant painting, galvanizing and powder coating as well as pickling and passivation to ensure optimum corrosion protection.

Surface treatments

Custom exhaust silencers

Frequency range

Silencer solutions for all frequency ranges


Manual and automated manufacturing


With the help of FEM calculations, we determine the structural strength, fatigue strength and material efficiency of your concept, among other things, in the early development phases. This gives you peace of mind during the test phases and after commissioning of your exhaust silencer CHP.

As part of the service, we digitally illustrate the effects of various mechanical, thermal and electrical loads on your product. To do this, we use a variety of linear and non-linear structural mechanical calculations. This allows us to examine the effects of various influences on the entire product or component before the prototype is built. There are no geometric limits, so that even very complex components can be investigated.

The results of our calculations can be used as evidence for technical approvals as well as for product liability and production releases. The FEM calculations of NovaNox® analytically follow the general and international standards. Thus we can guarantee you the reliability and comparability of the results.

We perform the following calculations and analyses for you:

  • linear and non-linear structural mechanics calculations
  • Analysis of deformations, stiffnesses and stability
  • consideration of natural vibrations
  • transient structural analyses
  • preparation of collision analyses
  • Realization of temperature field calculations (thermal-stationary or thermal-transient)
  • CAE-supported calculation of fatigue strength with nCode

We carry out sound level measurements of LAFmax, LAFmin and LCpeak for you on site. In order to determine the required power and the suitable design for your exhaust silencer, we carry out various measurements. These measurements are to give conclusion about the sound level distribution in the frequency range from 20 to 20,000 Hz.

We then calculate the insertion loss based on the planned design. This enables us to optimize the component, if necessary, so that your exhaust silencers achieve maximum sound attenuation in later use.

We already work closely with you during the development, planning and design of the construction. In doing so, we jointly plan the design of the material and the manufacturing process. This enables us to achieve a result that is very close to series production already in the prototype phase. This enables you to achieve the best results and also keep to your time and cost planning.

With the help of the FAI results, the manufacturing process is optimized for the highest efficiency and profitability. At the same time, we support you in shortening the time to market, so that a successful start to series production can be achieved on schedule. This saves your project budget and offers the highest reliability.

We carry out the entire process for you, from demand planning to logistics. In addition, we provide you with a total of 1,200 square meters of storage space as a consignment warehouse. This ensures uninterrupted production processes. This saves you costs compared to using your own warehouse space and allows you to produce larger batch sizes more cost-effectively.

The consignment warehouse ensures an optimum supply of components for your series production at all times. Your exhaust silencers for CHP units can also be delivered from the consignment warehouse on schedule and flexibly on demand. Your existing logistics processes are fully integrated. This ensures the optimal supply of components for your NovaNox® exhaust silencer CHP throughout the year.

If you have any further questions or would like to learn even more about our comprehensive services, book your free, no-obligation consultation with our experts here.

Quality management

Through welding process planning, we determine the optimal welding process for the particular criteria that your custom welded exhaust silencer needs to meet. At the same time, the safety and stability of your exhaust silencer CHP are increased. Furthermore, the ideal welding sequence is determined. The optimal sequence influences the efficiency of the manufacturing process and increases the service life of the welded exhaust silencer CHP. It also ensures that the exhaust silencer will reliably seal in your application area.

The type identification of the NovaNox® exhaust silencers CHP allows easy traceability back to their starting point. Thereby, the complete product life from manufacturing to the last use can be traced in detail. This proof gives you additional security. The type designation depends on the material and the stress on the exhaust silencer CHP. We offer the following variants:

  • Laser engraving
  • Welded metal plates with laser engraving
  • Self-adhesive metal signs with laser engraving
  • Self-adhesive plastic plates with specific imprint and silicone coating for external protection

These integrated personal identifiers (symbols, numbers, letters) simplify effective route and process tracking.

The leak test gives you the certainty that your exhaust silencers will remain absolutely leak-proof in continuous operation in your combined heat and power plants. We will be pleased to provide you with the result of this quality management process for each reference batch and as a written certificate of conformity. This NovaNox® test certificate can easily be integrated into your overall documentation. We perform the following leak tests for you:

  • 100% test with air under water in our own test basin (e.g. according to ECE R34 or 70/21EWG regulation)
  • Pressure test
  • Leak test by means of red or fluorescent dyes
  • Ultrasonic testing

We can guarantee the high standards of our products through reliable quality assurance in production. Here, precise documentation of the production processes is essential. Complete documentation enables errors and quality deviations to be detected in good time and then corrected immediately. This process brings enormous cost savings, especially for larger projects. Detailed documented and repeatable processes realize time savings. We offer the following verifications as part of our quality management:

  • Initial sample inspection report according to VDA 2, EN 9102
  • Factory certificates 3.1 and 2.2 according to EN 10204
  • Dimensional report by 3D measuring technique (Faro measuring arm)
  • Declaration of conformity for pressure tests

All mentioned documentations can be quickly and easily integrated into the overall documentation on your request. For an individual as well as free and non-binding initial consultation on the NovaNox® exhaust silencers CHP click here.