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Misunderstandings in the management of elevator guide rail noise

Views : 239
Author : Cobain
Update time : 2021-05-06 14:42:01
1.It is a wrong technical judgment to understand the rail noise as the wind pressure piston effect
High-speed elevator running speed is fast, there is a larger wellway pull wind will effect, so it is easy because of sensory error to understand elevator noise as wellway wind pressure causes, and thus lead to elevator noise control measures around how to reduce the wellway wind pressure piston effect (for example, the wellway wind vent or diffusion measures, etc.). Many governance companies and developers will simply understand elevator noise as wind pressure piston effect, and noise reduction measures only stay in the elevator wellway, machine room in and out of the wind improvement. On the contrary, these practical cases, its so-called noise reduction measures can only reduce the wind speed effect of the wellway to a certain extent, but can not be removed from the low rail vibration through the wall to the similar household interior transmission, so there is no obvious noise reduction effect. This reduction measure even costs a lot of manpower and material resources (sound absorption and sound insulation measures are calculated at 150to160 yuan / square,20 floors of well noise reduction costs nearly 100,000 yuan). It can be seen that it is a kind of wrong technical judgment to understand the rail noise as the elevator wind pressure piston effect.
2,simple elevator rail noise understanding wall soundproofing is another common processing error
We have always emphasized that noise management should make scientific analysis of noise sources in order to cure the disease. But many people on this issue will simply understand elevator noise as wall soundproofing, in the owner's complaints urgently need to be resolved when the doctor. Some noise-cancelling governance companies, driven by sales, default and advocate so-called elevator wellway sound insulation systems, and even advocate reducing wall impact sound by 10-20 decibels. Because sound insulation and vibration reduction are two different technical applications, so in fact, the so-called "wellway sound insulation system" is a cow's head is not right horse's mouth, and can not solve the problem of rail vibration. In terms of elevator rail noise source analysis, air sound is below 65 decibels, and the general wellway 200-240 thick concrete wall sound insulation will be more than 50 decibels, in terms of wall sound insulation performance, is fully able to meet the requirements of air sound insulation. We have added a noise source equivalent to the elevator operating noise level (approximately 65-70 decibels) to the inside of several elevator shafts and conducted wall air insulation tests in adjacent households, which showed that the noise source had no significant effect on the interior on the other side of the wall.
3,double concrete well wall design so that developers pay the greatest cost, but the noise is still there
In recent years, we have also seen companies in Shanghai and other places to solve the elevator noise problem proposed double concrete wall design. This design is due to elevator manufacturers based on concerns about the high-speed operation of elevator noise impact on similar households, so the developers put forward the requirements of well wall sound insulation. And developers based on some of the past governance failure experience after taking a breakthrough from the architectural design itself. From acoustic principle analysis, double concrete does have the positive effect of noise reduction: First, the double wall structure makes the sound insulation performance of the wellway wall greatly enhanced; However, economic benefits, double concrete wall design needs to pay a heavier price, in addition to each layer sacrifice nearly 3-5 square sets of inner area, but also to pay more than double the cost of well construction, so double concrete wall design is by no means the most scientific approach.
4,lightweight brick frame well wall structure, elevator rail noise will be more obvious
Based on the consideration of construction cost, some lightweight brick frame wellway wall structure is more commonly used, especially in second- and third-tier cities with relatively low housing prices. Although the construction cost of this elevator shaft structure is cheaper than the concrete wall, it will cause the elevator noise transmission faster, and the rail noise will affect the adjacent households to a greater extent. Based on case data collection, the easy-to-mass wall wellway structure is at least 4-6 decibels larger than the concrete wall structure. The vibration source of the elevator itself is fixed, and the area and mass of the vibration transmitted to the vibrating media (i.e. the wellway frame) is several times smaller. Therefore, the elevator rail vibration in the framework of the transmission will certainly be more obvious. If the lightweight brick of the well wall itself has poor sound insulation or leakage such as construction technology, the noise problem will be more serious. It can be seen that this kind of well wall will take elevator noise as the price while saving construction costs.
5,"unconventional means" (such as elevator speed reduction, etc.) to reduce the elevator rail noise in the end how much impact
What we call "unconventional" means is that governance requires functional sacrifices, such as "elevator downspeed" (i.e., reducing elevator speed). The noise itself comes from the high-speed taxiing vibration of the elevator, which reduces the speed of the elevator and naturally reduces the vibration. However, the elevator is different from the car, its host meshing is based on the elevator rated speed matching, so the speed reduction is not suitable for more than 10%,no side may cause damage to the elevator host, and after the speed reduction, the first to top level running time from the original 25 seconds to 35 seconds, poor handling will also cause residents to the elevator operating efficiency complaints. We came into contact with a 2.5 / elevator case, the elevator from 2.5 m / down to 2   / the owner's indoor noise from 48 decibels to about 42 decibels, noise reduction, but can not meet the needs of households and national standards.