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Noise measurements for a block boiler house. How to reduce the noise of a boiler room: at the design stage and with special means

Noise measurements for a block boiler house. How to reduce the noise of a boiler room: at the design stage and with special means

Soundproofing of a boiler room. In this publication we will look at the reasons higher level noise and vibrations from gas boilers and boiler rooms, as well as ways to eliminate them to achieve standard indicators and the level of comfort of residents.

Installation of autonomous modular gas boiler houses on roofs apartment buildings is becoming increasingly popular among developers. The advantages of such a boiler room are obvious. Among them

    There is no need to erect a separate building for boiler room equipment

    Reducing heat loss by 20% due to a small number of heating mains compared to heating from a central heating network

    Savings on installation of communications from the coolant to the consumer

    Absence of necessity forced ventilation

    The ability to fully automate the system with a minimum of maintenance personnel

One of the disadvantages of a rooftop boiler room is vibrations from the boiler and pumps. As a rule, they are the result of shortcomings in the design, construction and installation of boiler room equipment. Therefore, responsibility for eliminating the increased noise level and measures for soundproofing the boiler room lies with the developer or housing management company.

The noise from the boiler room is low-frequency and is transmitted through the structural elements of the building directly from the source and through communications. Its intensity in a room equipped as a boiler room is 85-90 dB. Sound insulation of a roof boiler room is justified if it is done from the source side, and not in the apartment. Soundproofing the ceiling and walls in an apartment with such noise is expensive and ineffective.

Causes of increased noise levels in a roof boiler room.

    Insufficient thickness and massiveness of the base on which the boiler room equipment stands. This leads to penetration airborne noise into apartments through the floor slab and technical floor.

    Lack of proper vibration insulation of the boiler. In this case, vibrations are transmitted to the ceilings and walls, which emit sound into the apartments.

    Rigid fastening of pipelines, communications and their supports is also a source of structural noise. Normally, pipes should pass through enclosing structures in an elastic sleeve, surrounded by a layer of sound-absorbing material.

    Insufficient pipeline thickness as a design error leading to high speed water movement and the creation of an increased level of hydrodynamic noise.

Soundproofing of a roof boiler room. List of events.

    Installation of vibration-isolating supports under boiler room equipment. Calculation of materials for vibration isolation is made taking into account the support area and weight of the equipment;

    Elimination of “rigid connections” in places where pipeline supports are attached using strength meter material, thermal and sound insulation material or installation of vibration fastenings on studs fixing communications;

    In the absence of elastic sleeves, the expansion of the passage of the pipeline through bearing structures, wrapping with an elastic material (k-flex, vibration stack, etc.) and a heat-resistant layer (basalt cardboard);

    Wrapping the pipeline with a material that reduces heat loss and has sound insulation properties: Texaund 2ft AL;

    Additional sound insulation of the enclosing structures of the roof boiler room;

    Installation of rubber compensators to reduce the transmission of vibrations through the pipeline;

    Installation of noise suppressors in the exhaust gas exhaust channel;

    Installation of noise-absorbing materials based on basalt (Stopzvuk BP) or fiberglass (Acoustiline fiber) can reduce background noise in the boiler room by 3-5 dB.

SOUNDPROOFING A BOILER IN A WOODEN HOUSE.

Building code rules and fire safety dictate the installation of the boiler in special room, equipped with a separate entrance. As a rule, it is located in the basement or basement. With this arrangement, complaints about increased noise levels from the boiler are rare.

A boiler installed on the same floor as living rooms, with high noise levels and complete silence in country house may cause inconvenience to residents. Therefore, soundproofing the boiler may be relevant.

The reasons for the increased noise level may be similar to those during the operation of a rooftop boiler room, but on a smaller scale. They are treated the same

    Design features of the outer casing of the boiler. In most boiler models, the burner and fan are closed with a separate damper, which reduces the noise produced by the burner. If the only soundproofing protection is the plastic casing of the boiler, the noise from the burner can be noticeable.

    Noisy fan from the manufacturer.

    Fan imbalance, dirt accumulation due to dust from outside and neglect of maintenance measures.

    Air entering the heating system.

    Incorrect gas burner setting.

    Rigid mounting system for the boiler and outlet pipes.

Boiler soundproofing begins with identifying the causes of increased noise levels and is related to the work of employees gas services servicing it or a company involved in soundproofing premises.

If the boiler and system are working properly, then

    We mount the boiler on a vibration-isolated platform on fastenings with a strength meter

    Install rubber expansion joints where pipes exit from the boiler body

    We purchase a soundproof casing for the boiler

    We make additional sound insulation of the walls of the boiler room

    To reduce background noise in the boiler room

Welcome to the Comfort Zone!

Ministry of Health of Russia

Moscow

1. Developed by the Research Institute of Occupational Medicine of the Russian Academy of Sciences (Suvorov G.A., Shkarinov L.N., Prokopenko L.V., Kravchenko O.K.), Moscow Research Institute of Hygiene named after. F.F. Erisman (Karagodina I.L., Smirnova T.G.).

2. Approved and put into effect by Resolution of the State Committee for Sanitary and Epidemiological Supervision of Russia dated October 31, 1996 No. 36.

3. Introduced to replace the “Sanitary Standards for Permissible Noise Levels in Workplaces” N 3223-85, “Sanitary Standards permissible noise in the premises of residential and public buildings and in residential areas" N 3077-84, "Hygienic recommendations for establishing noise levels in workplaces, taking into account the intensity and severity of work" N 2411-81.

APPROVED
Resolution of the State Committee for Sanitary and Epidemiological Supervision
Russia dated October 31, 1996 N 36
Date of introduction from date of approval

1. Scope and general provisions

1.1. These sanitary standards establish the classification of noise; standardized parameters and maximum permissible noise levels in workplaces, permissible noise levels in residential and public buildings and in residential areas.

1.2. Sanitary standards are mandatory for all organizations and legal entities in the territory Russian Federation regardless of forms of ownership, subordination and affiliation and individuals regardless of citizenship.

1.3. References and requirements of sanitary standards must be taken into account in State standards and in all regulatory and technical documents regulating planning, design, technological, certification, and operational requirements for production facilities, residential, public buildings, technological, engineering, sanitary equipment and machines, vehicles, household appliances.

1.4. Responsibility for compliance with the requirements of Sanitary Standards is assigned in accordance with the procedure established by law to managers and officials enterprises, institutions and organizations, as well as citizens.

1.5. Control over the implementation of Sanitary Standards is carried out by bodies and institutions of the State Sanitary and Epidemiological Supervision of Russia in accordance with the Law of the RSFSR “On the Sanitary and Epidemiological Welfare of the Population” dated April 19, 1991 and taking into account the requirements of current sanitary rules and norms.

1.6. Measurement and hygienic assessment of noise, as well as preventive measures, must be carried out in accordance with guideline 2.2.4/2.1.8-96 “Hygienic assessment physical factors production and environment"(under approval).

1.7. With the approval of these sanitary standards, “Sanitary standards for permissible noise levels in workplaces” N 3223-85, “Sanitary standards for permissible noise in residential and public buildings and in residential areas” N 3077-84, “Hygienic recommendations for establishing levels noise in workplaces, taking into account the intensity and severity of work" N 2411-81.

2.1. Law of the RSFSR “On the sanitary and epidemiological welfare of the population” dated April 19, 1991.

2.2. Law of the Russian Federation “On Environmental Protection” natural environment"from 12/19/91.

2.3. Law of the Russian Federation “On the Protection of Consumer Rights” dated 02/07/92.

2.4. Law of the Russian Federation “On Certification of Products and Services” dated June 10, 1993.

2.5. “Regulations on the procedure for the development, approval, publication, and enforcement of federal, republican and local sanitary rules, as well as on the procedure for the operation of all-Union sanitary rules on the territory of the RSFSR,” approved by Resolution of the Council of Ministers of the RSFSR dated 01.07.91 N 375.

2.6. Resolution of the State Committee for Sanitary and Epidemiological Supervision of Russia “Regulations on the procedure for issuing hygienic certificates for products” dated 01/05/93 N 1.

3. Terms and definitions

3.1. Sound pressure is a variable component of air or gas pressure resulting from sound vibrations, Pa.

3.2. Equivalent (energy) sound level, LА.eq., dBA, of intermittent noise - the sound level of constant broadband noise, which has the same root-mean-square sound pressure as this intermittent noise over a certain time interval.

3.3. The maximum permissible level (MAL) of noise is the level of a factor that, during daily (except weekends) work, but not more than 40 hours a week during the entire working period, should not cause diseases or deviations in the state of health detected modern methods research in the process of work or in the long term of life of the present and subsequent generations. Compliance with noise limits does not exclude health problems in hypersensitive individuals.

3.4. The permissible noise level is a level that does not cause significant disturbance to a person and does not cause significant changes in the functional state of systems and analyzers that are sensitive to noise.

3.5. Maximum sound level, LA.max., dBA - the sound level corresponding to the maximum indicator of a measuring, direct-indicating device (sound level meter) during visual reading, or the sound level value exceeded during 1% of the measurement time when registered by an automatic device.

4. Classification of noise affecting humans

4.1. Based on the nature of the noise spectrum, the following are distinguished:

  • broadband noise with a continuous spectrum more than 1 octave wide;
  • tonal noise, in the spectrum of which there are pronounced tones. The tonal nature of noise for practical purposes is established by measuring in 1/3 octave frequency bands by the excess of the level in one band over neighboring ones by at least 10 dB.

4.2. According to the temporal characteristics of noise, the following are distinguished:

  • constant noise, the sound level of which over an 8-hour working day or during measurement in the premises of residential and public buildings, in residential areas, changes over time by no more than 5 dBA when measured on the time characteristic of a sound level meter “slowly”;
  • non-constant noise, the level of which during an 8-hour working day, work shift or during measurements in the premises of residential and public buildings, in residential areas, changes over time by more than 5 dBA when measured on the time characteristic of a sound level meter “slowly”.

4.3. Variable noises are divided into:

  • time-fluctuating noise, the sound level of which continuously changes over time;
  • intermittent noise, the sound level of which changes stepwise (by 5 dBA or more), and the duration of the intervals during which the level remains constant is 1 s or more;
  • impulse noise consisting of one or more sound signals, each lasting less than 1 s, while the sound levels in dBAI and dBA, measured respectively on the “impulse” and “slow” time characteristics, differ by at least 7 dB.

5. Standardized parameters and maximum permissible noise levels in workplaces

5.1. Characteristics of constant noise in workplaces are sound pressure levels in dB in octave bands with geometric mean frequencies of 31.5; 63; 125; 250; 500; 1000; 2000; 4000; 8000 Hz, determined by the formula:

Where P is the root mean square value of sound pressure, Pa;
P0 — original value sound pressure in air equal to 2·10-5Pa.

5.1.1. It is allowed to take the sound level in dBA as a characteristic of constant broadband noise in workplaces, measured on the time characteristic of a “slow” sound level meter, determined by the formula:

Where PA is the root-mean-square value of sound pressure taking into account the correction “A” of the sound level meter, Pa.

5.2. A characteristic of non-constant noise in workplaces is the equivalent (energy) sound level in dBA.

5.3. Maximum permissible sound levels and equivalent sound levels in workplaces, taking into account the intensity and severity of work activity.

Quantitative assessment of the severity and intensity of the labor process should be carried out in accordance with Guideline 2.2.013-94 “Hygienic criteria for assessing working conditions in terms of harmfulness and danger of factors in the working environment, severity, intensity of the labor process.”

6. Standardized parameters and permissible noise levels in residential, public buildings and residential areas

6.1. The normalized parameters of constant noise are sound pressure levels L, dB, in octave bands with geometric mean frequencies: 31.5; 63; 125; 250; 500; 1000; 2000; 4000; 8000 Hz. For an approximate assessment, it is allowed to use sound levels LA, dBA.

6.2. The normalized parameters of non-constant noise are equivalent (in energy) sound levels LAeq., dBA, and maximum sound levels LAmax., dBA.

Assessment of non-constant noise for compliance with permissible levels should be carried out simultaneously based on the equivalent and maximum sound levels. Exceeding one of the indicators should be considered as non-compliance with these sanitary standards.

6.3. Permissible values ​​of sound pressure levels in octave frequency bands, equivalent and maximum sound levels of penetrating noise in residential and public buildings and noise in residential areas.

Bibliography

  • Guideline 2.2.4/2.1.8.000-95 “Hygienic assessment of physical factors of production and the environment.”
  • Guideline 2.2.013-94 “Hygienic criteria for assessing working conditions in terms of harmfulness and danger of factors in the working environment, severity, intensity of the labor process.”
  • Suvorov G. A., Denisov E. I., Shkarinov L. N. Hygienic standardization of industrial noise and vibrations. - M.: Medicine, 1984. - 240 p.
  • Suvorov G. A., Prokopenko L. V., Yakimova L. D. Noise and health (ecological and hygienic problems). - M: Soyuz, 1996. - 150 p.
  • Permissible levels of noise, vibration and sound insulation requirements in residential and public buildings. MGSN 2.04.97 (Moscow city building codes). - M., 1997. - 37 p.

Our site is ours business card. Just like on a business card, we displayed only the most necessary information, in our opinion.

Our website was created so that by visiting here you can call us:

  • boiler rooms, boiler equipment, heating boilers, burners
  • gas limits

And receive qualified answers to your questions within a reasonable time.

Work performed:

  • Obtaining technical specifications (TU) for the following types of work: gasification of the facility, water supply, electricity supply, sewerage. And also - all permitting documentation for boiler installations in the SES, Fire Service and other organizations. Gas limits - documentation preparation, receipt.
  • Boiler house design. It is provided both as a separate service and as part of a complex of works for the construction of turnkey boiler houses. For gas boiler houses, for diesel boiler houses and for wood fuel boiler houses. Design is carried out for the following facilities - gas boiler houses, diesel boiler houses and wood waste boiler houses.
  • Boiler equipment . Supply of imported and Russian equipment - directly through manufacturers. We provide discounts to design and installation organizations that make purchases through our representative offices. Basics boiler equipment: block modules, boilers, burners, heat exchangers, chimneys.

    You can also order the following boiler equipment separately:

    • gas boilers(small and medium power),
    • heating boilers,
    • burners (gas, diesel and combined),
    • block-modular buildings (made of sandwich panels).
  • Installation of boiler rooms is produced both at the Customer’s site and with the possibility of partial execution at the company’s base, with further delivery to the site and block assembly. Main types: block, modular boiler rooms, roof-mounted, built-in, attached, transportable.
  • Delivery of completed work. Carrying out all work on paperwork and interaction with representatives of supervisory authorities. Interaction with all structures involved in both steam boiler houses and hot water boiler houses.

Advantages:

  1. Deadlines, quality, price- everyone declares. Not everyone complies. We comply.
  2. The management department will deliver you maximum convenience when working with us.

Boiler rooms are designed and installed in accordance with a number of rules, for example:

  • GOST 21.606-95 SPDS "Rules for the implementation of working documentation for thermomechanical solutions for boiler houses"
  • GOST 21563-93 Water heating boilers. Main parameters and technical requirements
  • PU and BE "Rules for the design and safe operation of steam boilers"
  • PB 12-529-03 "Safety rules for gas distribution and gas consumption systems."

If your task is to obtain an active object back to the beginning heating season , we offer you the option "Block-modular boiler house" based standard solutions. Modular boiler houses supplied under this program have the following advantages: a) the use of a standard design reduces the time required for design and project approval, b) it becomes possible to purchase basic equipment in parallel with the development individual parts project.

We also translate steam boiler rooms in hot water mode. With this operation steam boilers lose from the rated power, while solving certain heating problems. These are solutions mainly for Russian boilers. The advantage of this operation is that existing steam boilers do not have to be replaced with new ones, which can have a positive effect in the short term from an economic point of view.

All supplied boiler equipment is certified and has permission for use in the Russian Federation - gas boilers, heating boilers, burners, heat exchangers, shut-off valves etc. The specified documentation is included in the delivery package.

The number of requests from citizens received by the Office of Rospotrebnadzor in the Tyumen Region about the deterioration of living conditions due to exposure to excess noise levels increases every year.

In 2013, 362 complaints were received (in total regarding violations of peace and quiet, accommodation and noise), in 2014 - 416 complaints, and in 2015, 80 complaints were already received.

According to established practice, after residents apply, the Department orders measurements of noise and vibration levels in residential premises. If necessary, measurements are carried out in organizations located near apartments, where, for example, “noisy” equipment is operated - a source of noise (restaurant, cafe, store, etc.). If noise and vibration levels exceed permissible values, in accordance with SN 2.2.4/2.1.8.562-96 “Noise in workplaces, in residential and public buildings and in residential areas”, addressed to the owners of noise sources - legal entities, individual entrepreneurs - the Department issues an order to eliminate identified violations of sanitary legislation.

How can you reduce the noise from the equipment listed above so that during its operation there are no complaints from the residents of the house? Certainly, perfect option-provide necessary measures at the design stage of a residential building, then the development of noise-reducing measures is always possible, and their implementation during construction is tens of times cheaper than in those houses that have already been built.

The situation is completely different if the building has already been built and there are noise sources in it that exceed current standards. Then, most often, noisy units are replaced with less noisy ones and measures are taken to isolate vibration from the units and the communications leading to them. Next, we will look at specific sources of noise and measures for vibration isolation of equipment.

NOISE FROM THE AIR CONDITIONER

The use of three-link vibration isolation, when the air conditioner is installed on the frame through a vibration isolator, and the frame - on a reinforced concrete slab through rubber gaskets (in this case, the reinforced concrete slab is installed on spring vibration isolators on the roof of the building), leads to a reduction in penetrating structural noise to levels acceptable in residential premises.

To reduce noise, it is necessary, in addition to strengthening the noise and vibration insulation of the air duct walls and installing a muffler on the air duct of the ventilation unit (from the premises), to attach the expansion chamber and air ducts to the ceiling through vibration-isolating hangers or gaskets.

NOISE FROM THE BOILER ROOM ON THE ROOF

To protect the boiler room located on the roof of the house from noise, the foundation slab of the roof boiler room is installed on spring vibration isolators or a vibration isolating mat made of a special material. Pumps and boiler units equipped in the boiler room are installed on vibration isolators and soft inserts are used.

Pumps in the boiler room must not be installed with the engine facing down! They must be installed in such a way that the load from the pipelines is not transferred to the pump housing. In addition, the noise level is higher with a higher power pump or if several pumps are installed. To reduce noise, the boiler room foundation slab can also be placed on spring shock absorbers or high-strength multilayer rubber and rubber-metal vibration isolators.

Current regulations do not allow the placement of a rooftop boiler room directly on the ceiling of residential premises (the ceiling of a residential premises cannot serve as the basis for the floor of the boiler room), as well as adjacent to residential premises. It is not allowed to design rooftop boiler houses on buildings of preschool and school institutions, medical buildings of clinics and hospitals with 24-hour stay of patients, on dormitory buildings of sanatoriums and recreational facilities. When installing equipment on the roof and ceilings, it is advisable to place it in places farthest from the protected objects.


NOISE FROM INTERNET EQUIPMENT

According to recommendations for the design of communication systems, informatization and dispatching of housing construction projects, antenna amplifiers cellular communication It is recommended to install in a metal cabinet with a locking device on technical floors, attics or staircases on upper floors. If it is necessary to install house amplifiers on different floors multi-storey buildings they should be installed in metal cabinets in close proximity to the riser under the ceiling, usually at a height of at least 2 m from the bottom of the cabinet to the floor.

When installing amplifiers on technical floors and attics, to eliminate the transmission of vibration from a metal cabinet with a locking device, the latter must be installed on vibration isolators.

EXIT - VIBRATION ISOLATORS AND “FLOATING” FLOORS

For ventilation, refrigeration equipment on the upper, lower and intermediate technical floors of residential buildings, hotels, multifunctional complexes or in the vicinity of noise-rated rooms where people are constantly present, the units can be installed on factory-made vibration isolators on a reinforced concrete slab. This slab is mounted on a vibration-isolating layer or springs on a “floating” floor (additional reinforced concrete slab on a vibration-isolating layer) in technical room. It should be noted that fans and external condenser units, which are currently produced, are equipped with vibration isolators only at the request of the customer.

“Floating” floors without special vibration isolators can only be used with equipment having operating frequencies of more than 45-50 Hz. These are, as a rule, small machines, the vibration isolation of which can be ensured in other ways. The effectiveness of floors on an elastic base at such low frequencies is low, so they are used exclusively in combination with other types of vibration isolators, which provides high vibration isolation at low frequencies (due to vibration isolators), as well as at medium and high frequencies (due to vibration isolators and a “floating” floor ).

The floating floor screed must be carefully isolated from the walls and the load-bearing floor slab, since the formation of even small rigid bridges between them can significantly worsen its vibration-isolating properties. Where the “floating” floor adjoins the walls there must be a seam made of non-hardening materials that does not allow water to pass through.

NOISE FROM THE GARBAGE CHIP

To reduce noise, it is necessary to comply with the requirements of the standards and not design the waste chute adjacent to residential premises. The garbage chute should not be adjacent to or located in walls enclosing residential or office premises with regulated noise levels.

The most common measures to reduce noise from garbage chutes are:

  • “floating” floors are provided in waste collection rooms;
  • with the consent of the residents of all apartments at the entrance, the garbage chute is sealed (or eliminated) with the placement of a garbage chamber for wheelchairs, a concierge room, etc. in the premises. (the positive thing is that in addition to noise, odors disappear, the possibility of rats and insects, the likelihood of fires, dirt, etc. is eliminated);
  • ladle loading valve mounted framed with rubber or magnetic seals;
  • decorative heat and noise insulating lining of the garbage chute trunk made of building materials separated from building structures buildings with soundproofing pads.

Today many construction companies offer their services, various designs to increase the sound insulation of walls and promise complete silence. It should be noted that in fact, no structures can remove the structural noise transmitted through the floors, ceilings and walls when disposing of solid household waste into a garbage chute.

NOISE FROM ELEVATORS

In SP 51.13330.2011 “Noise protection. The updated version of SNiP 23-03-2003" states that it is advisable to locate elevator shafts in staircase between flights of stairs (clause 11.8). When making an architectural and planning decision for a residential building, it should be provided that the built-in elevator shaft is adjacent to rooms that do not require increased protection from noise and vibration (halls, corridors, kitchens, sanitary facilities). All elevator shafts, regardless of the planning solution, must be self-supporting and have an independent foundation.

The shafts must be separated from other building structures with an acoustic seam of 40-50 mm or vibration-isolating pads. Acoustic mineral wool slabs on a basalt or fiberglass base and various foamed polymer roll materials are recommended as the material for the elastic layer.

To protect the elevator installation from structural noise, its drive motor with gearbox and winch, usually installed on one common frame, are vibration-isolated from the supporting surface. Modern elevator drive units are equipped with appropriate vibration isolators installed under metal frames on which motors, gearboxes and winches are rigidly mounted, and therefore additional vibration insulation of the drive unit is usually not required. In this case, it is additionally recommended to make a two-stage (two-link) vibration isolation system by installing a support frame through vibration isolators on a reinforced concrete slab, which is also separated from the floor by vibration isolators.

The operation of elevator winches installed on two-stage vibration isolation systems has shown that noise levels from them do not exceed standard values ​​in the nearest residential premises (through 1-2 walls). For practical purposes, care must be taken to ensure that vibration isolation is not compromised by occasional rigid bridges between the metal frame and the supporting surface. Electrical supply cables must have sufficiently long flexible loops. However, the operation of other elements of elevator installations (control panels, transformers, cabin and counterweight shoes, etc.) may be accompanied by noise above standard values.

It is prohibited to design the elevator engine room floor as a continuation of the ceiling slab of the upper floor living room.

NOISE FROM TRANSFORMERSSUBSTATIONSON THE GROUND FLOORS

To protect residential and other premises with regulated noise levels from noise from transformer substations, the following conditions must be observed:

  • premises of built-in transformer substations;
  • should not be adjacent to noise-protected premises;
  • built-in transformer substations should
  • located in basements or on the first floors of buildings;
  • transformers must be installed on vibration isolators designed accordingly;
  • electrical panels, containing electromagnetic communication devices, and separately installed oil switches with electric drive must be mounted on rubber vibration isolators (air disconnectors do not require vibration insulation);
  • ventilation devices premises of built-in transformer substations must be equipped with noise suppressors.

To further reduce noise from the built-in transformer substation, it is advisable to treat its ceilings and interior walls sound-absorbing cladding.

In built-in transformer substations protection against electromagnetic radiation must be provided (a mesh made of a special material with grounding to reduce the level of radiation from the electrical component and a steel sheet for the magnetic one).

NOISE FROM ATTACHED BOILER ROOMS,BASEMENT PUMPS AND PIPES

Boiler room equipment (pumps and pipelines, ventilation units, air ducts, gas boilers, etc.) must be vibration-insulated using vibration foundations and soft inserts. Ventilation units are equipped with silencers.

To vibration-isolate pumps located in basements, elevator units in individual heating units (IHP), ventilation units, refrigeration chambers, and the above equipment are installed on vibration foundations. Pipelines and air ducts are vibration-insulated from the house structures, since the predominant noise in apartments located above may not be the basic noise from equipment in the basement, but that which is transmitted to the enclosing structures through vibration of pipelines and equipment foundations. It is prohibited to install built-in boiler rooms in residential buildings.

In piping systems connected to the pump, it is necessary to use flexible inserts - rubber-fabric hoses or rubber-fabric hoses reinforced with metal spirals, depending on the hydraulic pressure in a network, 700-900 mm long. If there are pipe sections between the pump and the flexible insert, the sections should be attached to the walls and ceilings of the room on vibration-isolating supports, suspensions or through shock-absorbing pads. Flexible inserts should be located as close as possible to the pumping unit, both on the discharge and suction lines.

To reduce noise and vibration levels in residential buildings from the operation of heat and water supply systems, it is necessary to isolate the distribution pipelines of all systems from the building structures in the places where they pass through the load-bearing structures (entry into residential buildings and conclusions from them). The gap between the pipeline and the foundation at the inlet and outlet must be at least 30 mm.


Prepared based on materials from the journal Sanitary-Epidemiological Interlocutor (No. 1(149), 2015

Ph.D. L.V. Rodionov, head of the support department scientific research; Ph.D. S.A. Gafurov, senior Researcher; Ph.D. V.S. Melentyev, senior researcher; Ph.D. A.S. Gvozdev, Samara National Research University named after Academician S.P. Koroleva", Samara

To provide hot water and heating to modern apartment buildings (MCDs), rooftop boiler houses are sometimes included in projects. This decision in some cases it is cost-effective. At the same time, often when installing boilers on foundations, proper vibration insulation is not provided. As a result, residents of the upper floors are subject to constant noise exposure.

According to the sanitary standards in force in Russia, the sound pressure level in residential premises should not exceed 40 dBA during the day and 30 dBA at night (dBA is an acoustic decibel, a unit of measurement of noise level taking into account human perception of sound. - Ed.).

Specialists from the Institute of Machine Acoustics at Samara State Aerospace University (IAM at SSAU) measured the sound pressure level in the living space of an apartment located under the roof boiler room of a residential building. It turned out that the source of the noise was the roof boiler room equipment. Despite the fact that this apartment is separated from the roof boiler room by a technical floor, according to the measurement results, an excess of daily sanitary standards was recorded, both at the equivalent level and at an octave frequency of 63 Hz (Fig. 1).

The measurements were performed during the daytime. At night, the operating mode of the boiler room remains virtually unchanged, and the background noise level may be lower. Since it turned out that the “problem” was already present during the day, it was decided not to carry out measurements at night.

Picture 1 . Sound pressure level in the apartment compared to sanitary standards.

Localizing the source of noise and vibration

To more accurately determine the “problem” frequency, measurements of the sound pressure level in the apartment, boiler room and on the technical floor were carried out in different operating modes of the equipment.

The most typical mode of equipment operation, in which a tonal frequency appears in the low-frequency region, is the simultaneous operation of three boilers (Fig. 2). It is known that the frequency of boiler operating processes (combustion inside) is quite low and falls in the range of 30-70 Hz.

Figure 2. Sound pressure level in various rooms when three boilers are operating simultaneously

From Fig. 2 shows that the frequency of 50 Hz prevails in all measured spectra. Thus, the main contribution to the spectra of sound pressure levels in the rooms under study is made by boilers.

The level of background noise in the apartment does not change much when the boiler equipment is turned on (except for the frequency of 50 Hz), so we can conclude that the sound insulation of the two floors separating the boiler room from the living rooms is sufficient to reduce the level of airborne noise produced by the boiler equipment to sanitary standards. Therefore, you should look for other (not direct) ways of spreading noise (vibration). Probably, high level sound pressure at 50 Hz is due to structural noise.

To localize the source of structural noise in residential premises, as well as to identify vibration propagation paths, vibration acceleration measurements were additionally carried out in the boiler room, on the technical floor, as well as in the living space of the apartment on the top floor.

The measurements were carried out at various operating modes of boiler equipment. In Fig. Figure 3 shows the vibration acceleration spectra for the mode in which all three boilers operate.

Based on the results of the measurements, the following conclusions were made:

– in the apartment on the top floor under the boiler room, sanitary standards are not met;

– main source increased noise in residential premises is the working process of combustion in boilers. The prevailing harmonic in the noise and vibration spectra is the frequency of 50 Hz.

– lack of proper vibration isolation of the boiler from the foundation leads to the transfer of structural noise to the floor and walls of the boiler room. Vibration spreads both through the boiler supports and through the pipes with transmission from them to the walls, as well as the floor, i.e. in places where they are rigidly connected.

– measures should be developed to combat noise and vibration along the path of their propagation from the boiler.

A) b)
V)

Figure 3 . Vibration acceleration spectra: a – on the support and foundation of the boiler, on the floor of the boiler room; b – on the support of the boiler exhaust pipe and on the floor near the boiler exhaust pipe; c – on the wall of the boiler room, on the wall of the technical floor and in the living area of ​​the apartment.

Development of a vibration protection system

Based on a preliminary analysis of the mass distribution of the structure gas boiler and equipment, cable vibration isolators VMT-120 and VMT-60 with a rated load on one vibration isolator (VI) of 120 and 60 kg, respectively, were selected for the project. The vibration isolator diagram is shown in Fig. 4.

Figure 4. 3D model of cable vibration isolator model range TDC.


Figure 5. Vibration isolator fastening schemes: a) support; b) suspended; c) lateral.

Three variants of the vibration isolator fastening scheme have been developed: support, suspended and side (Fig. 5).

Calculations have shown that the lateral installation scheme can be implemented using 33 vibration isolators VMT-120 (for each boiler), which is not economically feasible. In addition, very serious welding work is expected.

When implementing a suspended scheme, the entire structure becomes more complicated, since wide and sufficiently long corners must be welded to the boiler frame, which will also be welded from several profiles (to provide the necessary mounting surface).

In addition, the technology for installing the boiler frame on these skids with VIs is complex (it is inconvenient to attach the VIs, it is inconvenient to position and center the boiler, etc.). Another disadvantage of this scheme is the free movement of the boiler in lateral directions (swinging in the transverse plane on the VI). The number of vibration isolators VMT-120 for this scheme is 14.

The frequency of the vibration protection system (VPS) is about 8.2 Hz.

The third, most promising and technologically simpler option is with a standard support circuit. It will require 18 vibration isolators VMT-120.

The calculated frequency of the VZS is 4.3 Hz. In addition, the design of the VIs themselves (part of the cable rings are located at an angle) and their proper placement around the perimeter (Fig. 6) allows such a design to accommodate a lateral load, the value of which will be about 60 kgf for each VI, while the vertical load on each VI is about 160 kgf.


Figure 6. Placement of vibration isolators on the frame with a support diagram.

Design of a vibration protection system

Based on data from static tests and dynamic calculations of VI parameters, a vibration protection system for a boiler room in a residential building was developed (Fig. 7).

The vibration protection facility includes three boilers of the same design 1 installed on concrete foundations with metal ties; piping system 2 for the supply of cold water and the removal of heated water, as well as the removal of combustion products; pipe system 3 for supplying gas to the boiler burners.

The created vibration protection system includes external vibration protection supports for boilers 4 designed to support pipelines 2 ; internal vibration protection belt of boilers 5 , designed to isolate vibration of boilers from the floor; external anti-vibration mounts 6 For gas pipes 3.


Figure 7. General form boiler room with installed vibration protection system.

Basic design parameters vibration protection systems:

1. The height from the floor to which it is necessary to raise the load-bearing frames of the boilers is 2 cm (installation tolerance minus 5 mm).

2. Number of vibration isolators per boiler: 19 VMT-120 (18 - in the internal belt bearing the weight of the boiler, and 1 - on the external support to dampen vibrations of the water pipeline), as well as 2 vibration isolators VMT-60 on external supports - for vibration protection of the gas pipeline.

3. The “support” type loading scheme works in compression, providing good vibration isolation. The natural frequency of the system is in the range of 5.1-7.9 Hz, which provides effective vibration protection in the region above 10 Hz.

4. The damping coefficient of the vibration protection system is 0.4-0.5, which provides a gain at resonance of no more than 2.6 (oscillation amplitude no more than 1 mm with an input signal amplitude of 0.4 mm).

5. To adjust the horizontality of the boilers, nine U-shaped profiles are provided on the sides of the boiler seats for vibration isolators of a similar type. Only five are nominally installed.

During installation, it is possible to place vibration isolators in any order in any of the nine places provided to achieve alignment of the center of mass of the boiler and the center of rigidity of the vibration protection system.

6. Advantages of the developed vibration protection system: simplicity of design and installation, insignificant rise of boilers above the floor, good damping characteristics of the system, possibility of adjustment.

The effect of using the developed vibration protection system

With the introduction of the developed vibration protection system, the sound pressure level in the residential premises of the upper floor apartments decreased to an acceptable level (Fig. 8). The measurements were also carried out at night.

From the graph in Fig. 8 it can be seen that in the normalized frequency range and at the equivalent sound level, sanitary standards in residential premises are met.

The effectiveness of the developed vibration protection system when measured in a residential area at a frequency of 50 Hz is 26.5 dB, and at an equivalent sound level of 15 dBA (Fig. 9).


Figure 8 . Sound pressure level in the apartment in comparison with sanitary standards, taking into account developed vibration protection system.


Figure 9. Sound pressure level in one-third octave frequency bands in a living room when three boilers are operating simultaneously.

Conclusion

The created vibration protection system makes it possible to protect a residential building equipped with a roof boiler room from vibrations created by the operation of gas boilers, as well as to ensure normal vibration operating conditions for the most gas equipment together with the pipeline system, increasing the service life and reducing the likelihood of accidents.

The main advantages of the developed vibration protection system are simplicity of design and installation, low cost in comparison with other types of vibration isolators, resistance to temperatures and pollution, insignificant rise of boilers above the floor, good damping characteristics of the system, and the possibility of adjustment.

The vibration protection system prevents the propagation of structural noise from the roof boiler room equipment throughout the building structure, thereby reducing the sound pressure level in residential premises to an acceptable level.

Literature

1. Igolkin, A.A. Reducing noise in residential premises through the use of vibration isolators [Text] / A.A. Igolkin, L.V. Rodionov, E.V. Shakhmatov // Security in the technosphere. No. 4. 2008. pp. 40-43.

2. SN 2.2.4/2.1.8.562-96 “Noise in workplaces, in residential and public buildings and in residential areas,” 1996, 8 p.

3. GOST 23337-78 “Noise. Methods for measuring noise in residential areas and in residential and public buildings”, 1978, 18 p.

4. Shakhmatov, E.V. A comprehensive solution to the problems of vibroacoustics of mechanical engineering and aerospace engineering products [Text] / E.V. Shakhmatov // LAP LAMBERT Academic Publishing GmbH&CO.KG. 2012. 81 p.

From the editor. On October 27, 2017, Rospotrebnadzor published information on its official website “On the impact of physical factors, including noise, on public health”, which notes that in the structure of citizens’ complaints about various physical factors, the largest specific gravity(over 60%) are complaints about noise. The main ones are complaints from residents, including acoustic discomfort from ventilation systems and refrigeration equipment, noise and vibration during operation of heating equipment.

The reasons for the increased noise level generated by these sources are the insufficiency of noise protection measures at the design stage, installation of equipment with deviations from design solutions without assessing the generated levels of noise and vibration, unsatisfactory implementation of noise protection measures at the commissioning stage, placement of equipment not provided for by the design, and also unsatisfactory control over the operation of equipment.

The Federal Service for Supervision of Consumer Rights Protection and Human Welfare draws the attention of citizens that in the event of adverse effects of physical factors, incl. noise, you should contact the territorial Office of Rospotrebnadzor for the constituent entity of the Russian Federation.

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