Industrial noise is a combination of various noises that occur during the production process and adversely affect the human body system.
The modern concepts of labor protection consider noise as a threat for safety and labor health in many professions for several reasons. Noise can lead not only to hearing impairment (in case of constant presence at a noise of more than 80 decibels) but also can be a stress factor and a reason to increase the blood pressure which can lead to heart problems.
Noise isolation of pipelines and equipment determines the technical feasibility and economic efficiency of carrying out most technological operations.
Standard of noise isolation in projects and the permissible noise level are regulated by SNiP 23.103.2003, sanitary and environmental requirements are mandatory. This means that failure to comply the requirements is a reason for refusing to issue a permit to operate the facility until violations are eliminated.
Impact noise occurs when equipment receives a shock, noise vibrations are transmitted to all structural elements. Noise vibrations can spread far enough over structures, since they are transmitted to all adjacent communication elements.
Structure-noise occurs when vibrations are transmitted by pipes, ventilation shafts and other communication elements. Some elements of communication can transmit sounds over long distances.
Acoustic noise most often occurs in large rooms and manifests itself as an echo
Noise propagation paths
Airborne noise penetrating through non-densities (slots, holes) QRNI
At very low frequencies, QRNI provides significant noise absorption at high frequencies, when the dimensions of the casing are small in comparison with the sound wavelength and when there is little or no sound absorption of the inner shell of the QRNI, the inner volume of the QRNI and the edges of the holes form a resonator.
Noise penetrating through the sides of the QRNI
At the same time, the QRNI seal well and ensure the absence of side noise arising from vibration. At low frequencies, the air volume between the isolated object and the nearest side of the QRNI can resonate at the frequency of the side oscillations, which minimizes insertion loss. At medium and high frequencies, the losses at the QRNI are significant.
Radiation at natural bending vibrations of the QRNI sides
Usually the shell of the QRNI is tough. Therefore, emissivity is low and is mainly caused by vibrations of the clamped edges or areas adjacent to the attachment points.
Side noise with performance, caused by vibration and airborne noise from sources outside the control of the QRNI

1. Sound isolating layer – MAXFORT-SOUNDPRO mats

2. End perforated protective coating QRNI

3. Noise reduction fiber inserts

4. Bottom end perforated protective coating QRNI

5. Internal perforated safety closure QRNI

6. Distance springs

1. External protective coating QRHNI is made of stainless steel 12X18H10T

2. The handles are fixed on the outer cover of the QRNI with pull-out vents. Designed for ease of movement, assembly and disassembly

3. Adjustable lock - stretching L = 150-180 - is a universal fixing element, the peculiarity of which allows you to reliably adjust the degree of bonding of two surfaces. The lock possibility of adjusting the vent in length, and with the correct selection of the required compression ratio, the lock becomes highly resistant to vibration

4. The protective curtain is made of stainless steel 12X18H10T. Serves to reduce losses through "sound bridges", as well as to increase noise immunity

“Sound Bridges” as named are formed at the compound areas of the blocks. Additional inserts made of noise-reducing material used to reduce noise penetration. Working temperature of noise-reducing material from -30 to +80 ° С

1. Made of stainless steel 12X18H10T 0.8 mm thick

2. Provides a sufficiently large noise absorption in any frequency range

3. Mounted on the inner and side surfaces of the unit

4.Provides additional block strength

5.Sound absorption is regulated by the size and shape of the port and percentage of perforation
Noise-Reducing Layer
MAXFORT-SOUNDPRO is a new generation material that not only effectively isolates from noise, but is also easy to install.
  • 100% ECO-safe
  • Contains no adhesives ، phenol ، slags and other chemicals
  • Absolutely non-flammable
  • Material complies with GOST 2729687
  • Excellent performance in noise absorption in various premises
  • There is no unpleasant smell
  • Excellently isolates against impact and airborne noise


1. Reduction of the amplitude of vibrations coming from equipment and pipelines

2. Reduction of noise and vibration levels up to 85%

3. Vibration uptake - the vibration energy does not return to the source, but goes into heat

Remote Elements

To reduce the noise conductivity and reduce the mass of the QRNI, multilayer fences are used, for which the space between the layers is filled with porous-fibrous materials and an air gap with a width of 40-60 mm is left.
When sound energy meets the fence, part of it passes through the fence, part of it is reflected, part is converted into thermal energy, part is emitted by an oscillating obstacle, and part is converted into body sound, which spreads and gilded inside the QRNI.
The amount of the radiated sound energy is much less than the sound energy acting on the QRNI from the side of the noise source, where part of the acoustic energy is reflected.
To ensure the thickness of the air gap, the QRNI unit is designed in such a way that there is no direct contact between the QRNI and the isolated object, which provides excellent noise insulation

1. Madeof 65g springsteel

2. Made in the form of a flat spring of a specially calculated and designed shape for full absorption of thermal expansion

3. Attached to the inner protection of the casing with stainless steel blind rivets

4. The number of springs on the inner cover depends on the weight and length of the block

When installing distance springs on the internal protection of the QRTI, thermal conductivity bridges are created.

2. Air gap
3. Isolated Equipment
4. Spring
5. CeramicFiber

To eliminate this effect on the distance springs, heat – absorbing protective elements made of ceramic material ALSIFLEX are installed.

ALSIFLEX fibers are light weight and flexible insulation material with high temperature resistance, low thermal conductivity and high chemical stability.

Uniform structure free of long fiber bonding material ensures high performance. ALSIFLEX complies with CT 1260 c and density of 130 kg/m3.

Protective curtains made of stainless steel 12X18H10T as an additional element in the QRTI design to reduce losses through "thermal bridges", as well as to increase the thermal protection at the end of the blocks.

The protective canopies also protect the entire QRNI structure assembled around the perimeter of the pipeline or other equipment from moisture and exposure to corrosive environments.

The protective curtain is mounted on the QRNI unit using stainless steel rivets.

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ОГРН 1063332013293

ИНН 3305056645
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