Discussion on the practical research and analysis of noise control of elevator guide rail
Author: Ma Denghua
With the continuous improvement of people's living conditions and health awareness, people's living environment is no longer only to meet the basic requirements of living and living, but also to meet the comfortable requirements of personal living. Based on the continuous improvement of our living environment requirements and the lack of experience and neglect of some design details under the rapid development of real estate in our country, the problem of elevator guide rail running noise becomes another important topic of elevator noise prevention after "elevator machine room running noise". Although the emergence of the above problems has attracted the attention of most developers and elevator manufacturers, but based on the lack of existing technology and research, the problem of "elevator guide rail prevention" has become a technical problem that plagues the development of elevators and buildings! In order to promote the further development of elevator noise prevention and control technology, the author will combine the research and some practical experience in the field of elevator guide rail noise prevention and control for many years, and make a statement of its causes, treatment methods and common prevention methods and treatment errors one by one, so as to provide technical reference for large elevator manufacturers and construction developers:
1、 The cause of elevator guide noise
From the current case of elevator guide rail noise, at present in China, the main noise of elevator guide rail is high-rise residential buildings, and most of them are high-speed elevators. In order to save cost or realize the largest inner area, the developer generally adopts the structural design that elevator shaft and household are the same public wall in the design, and the fixed bracket of elevator guide rail is directly fixed on the public wall of the same wall with the owner, so the rigid connection between the guide rail and the public wall forms the vibration transmission sound bridge, and the vibration grinding of elevator in high-speed sliding The eraser is transmitted to the adjacent households through the sound bridge connection. As far as the installation and fixing technology and installation method of elevator guide rail in China are concerned, the existing technology basically adopts angle iron bracket or bending steel plate to fix the elevator guide rail directly. In the existing technology, in order to reduce the transmission of the sliding friction vibration of the elevator guide rail and ensure the comfort of the elevator when it is running, most manufacturers currently adopt the roller sliding guide shoes and a single spring as the technical means to solve the high-speed sliding friction vibration of the car and counterweight. Although this method solves the comfortable operation of the elevator car to a large extent, it is very limited in the solid transmission control of the sliding friction vibration of the guide rail through the building structure. In addition, as far as the current elevator design is concerned, the high-speed elevator is based on the consideration of the stress safety of the elevator, and most of the high-speed elevators adopt the steel wire rope rewinding hanging hoisting design. In this design, the reverse rope wheel device is set at the car side and counterweight side of the elevator. The vibration caused by the high-speed operation of the reverse rope wheel and the friction vibration between the reverse rope and the steel wire rope often form the vibration superposition effect. Through the guide rail Connect the sound bridge to the nearby building structure room. From the cases we have contacted for many years, the low frequency vibration of this kind of vibrating structure is more annoying than the "vibration and noise of elevator machine room"! Especially for the high-speed elevator, the obvious vibration can be felt on the indoor wall. The building vibration of the hoistway wall with the frame light wall structure is more intense. In serious cases, the indoor noise when the elevator is running is as high as 50-60 decibels, just like the typhoon, which has a serious impact on the households close to the hoistway. When people are resting indoors in the dead of night, it is easy to affect the normal rest of the residents downstairs of the machine room due to the low-frequency vibration and noise of the elevator (this situation is more obvious when the doors and windows of the households are closed in winter), thus causing complaints. With the increasing awareness of the rule of law and health of Chinese people, more and more complaints and lawsuits about "elevator noise" have become a new social problem in the development of elevators and buildings.
2、 Analysis of the objective conditions hindering the noise prevention and control of domestic elevator guide rail
In terms of the prevention and control of elevator guide rail noise in China, although basically all elevator manufacturers or developers have more or less experienced the problem of "elevator guide rail noise", and also have carried out some corresponding design or prevention research and consideration, but often due to the limitations of existing objective conditions, they failed to make a breakthrough in the prevention and control. From our research on elevator noise control over the years, I personally believe that the objective reasons that hinder the development of elevator guide rail noise control technology in China are as follows:
1. The noise control of elevator guide rail belongs to the edge science of the industry, which is difficult to study!
The noise of elevator guide rail is different from the general noise control and belongs to low-frequency vibration pollution (the general noise is air as the sound transmission medium, while the noise of elevator guide rail is low-frequency vibration, which is mainly manifested as vibration solid sound transmission). The conventional noise reduction measures (such as adding sound insulation board, sound absorption cotton or sound insulation wall) involved in our daily noise reduction can only reduce or block the noise with air as the sound transmission medium, but have no obvious effect on the low-frequency vibration transmission reduction of elevator guide rail transmitted by rigid structure vibration. From the technical level of solving the problem, the noise control of structural vibration transmission should belong to the field of noise and vibration control technology of environmental protection industry. However, as the elevator is a special equipment related to personal safety, the corresponding technical research involves the safety operation factors of the elevator, and there is also the problem of whether the construction qualification and the improvement measures studied meet the National Elevator acceptance standards, leading to the noise control leader