Fire R & D: How to correctly develop high-rise fire escape products

First, the status quo

When people's work and life develop more and more toward high altitudes, people's means of escape become more and more difficult as the number of buildings increases. In some fire emergencies, the passages that could have enabled people to escape quickly were filled with toxic fumes and blocked by high temperature, which became the most dangerous place. Because of the constraints of the existing rescue equipment itself and traffic congestion, the rescuers were very Difficult to get to the scene for the first time.

Outside the building through the window, balcony, etc. use the escape descent equipment to escape into an effective self-help method. In the face of sudden high-rise fires, existing fire-fighting and rescue equipment can not keep up with the development of high-rise buildings, and the natural expression of fire rescue is not satisfactory. Therefore, we are far from the fire drill scene we saw on TV, even if we face a height only. In a building fire within a hundred meters, the public could not see a very effective rescue means to show, nor could they see the use of high-rise fire escape products. Although firefighting is publicized year after year, many times when high-rise fires are still unstoppable and firefighting cannot be resolved, it is necessary to find ways to develop new types of fire escape and self-rescue products on rescue equipment and escape products, which is easier to achieve than the development of rescue equipment. Less investment. It is also convenient for the promotion of safe and reliable escape products, and at the same time, publicizing the public is an urgent task, so that the public can understand and master the use of such products as soon as possible so as to make preparations as early as possible.

Second, the special environment and people used for escape descending

A fire escape product is a life-saving product closely related to life. It must not be false and careless. When you decide to develop such a product, you need to have a clear understanding of the environment in which the product is used to descend and the people who use it. Does the escape product need escape control? Still need to manipulate? It is also necessary to make a correct assessment and not make mistakes in R&D and promotion. Because in a high-rise building fire, toxic smoke thickens, it will stimulate the eyes of the evacuees. It will cause breathing difficulties, and the instantaneous heat of killing will threaten the life of the user at any time, so all this will affect the user’s actions. In this kind of environment, escape products must be able to operate quickly, and the operation must be simple and fast! is very important. Escape products in use will be affected by high temperatures, spray water, smoke and dust, must be able to work properly. Therefore, the metal materials used in the escape products and the processing technology must also be carefully selected and designed.

Escape products face the use of the population including men, women, old, young, sick, weak, disabled, and most of these people have not received fire escape training. Does the escape product need to be controlled by the escapee during its use? Obviously, for products over 6 meters in height, products that escapers need to control must not be developed and used. Rope ladders, for example, are extremely unsafe to use in a fire building. Accidents occur, and the company’s promotion department cannot escape legal disputes. .

Fire escape products are different from poisonous products such as tainted milk powder, waste oil, and genetically modified products. The damage to the body after eating wrong can't be seen for a moment. If there is a safety hazard in a high-rise fire escape product, the product is not reliable during use or training. The accidents caused by the damage caused to the user are heavy, ranging from disability! Although the fire escape product is just a civilian product, the practical standards for the environment it uses and the people who use it have surpassed military products. With the above knowledge, you will reasonably determine the product's strength coefficient, reliability index and product technical standards. You will have a clear understanding of the rationality of the product in the use of the need to manipulate or not to manipulate the way. knowledge. In this way, it is possible to develop and promote truly safe and safe high-rise fire escape products.

Third, the selected institutions and determine the technical indicators

What scheme is used to achieve a uniform decrease of the object? In physics, when an object is high, it has gravitational potential energy, and the higher the potential energy is, the greater it will be.

There are several ways to consume this potential energy: electromagnetic damping, hydraulic damping, mechanical friction damping, mechanical transmission efficiency damping, fan damping, escapement mechanism, roller collision mechanism, compression spring mechanism, crank transmission mechanism, and so on.

In all of these methods, the conversion of potential energy occurs as a result of heat generation. Only the escapement mechanism and the roller collision mechanism perform in a thermal and acoustic manner. The problem is that the control of a 100- kilogram human body (with an upper limit) falls at a uniform rate. How much is your best weight?

Obviously, if the controller's own weight is more than ten kilograms, its weight-to-weight ratio is: 100/10=10 . The descending device used by a single person uses such a weight, has low mechanical utilization efficiency, is inconvenient to use, and the production cost is also increased. .

The greater the control weight ratio, the more convenient the use of the operation, the lower the cost, but to ensure sufficient strength. Usually 40 to take control weight index - 60, more than 60 necessary efforts in the metal material. Fire escape products are expressed in the words “fast and live”. The installation and operation are fast, and the fixing method needs to be live, and the control weight ratio is low. Obviously, such requirements cannot be met.

At present, engineers all over the world have chosen to use centrifugal friction mechanisms to control the rate of human body descent. Obviously, they lack knowledge of military products scientific research theory, and they do not understand the reliability of professional knowledge before choosing this coefficient of friction and centrifugal force are changing. Institutions. That is, the heat energy generated by the friction damping of the speed increaser balances the gravitational potential energy. When this type of descent device works, most of the gravitational potential energy becomes frictional heat energy, and a small part is consumed in the mechanical transmission efficiency, although the descent control weight is lower than the general descent. In the 40-60 or so to meet the requirements, but the biggest problem with the centrifugal friction type descending device is the reliability of instability (non-metallic friction plate is easy to aging, humidity, chemical vapors have an impact on them), not easy to store, new products in a row After a few uses, the rate of descent will appear vibrating, that is, intermittent out of control, and finally completely out of control, the world has used this kind of slow down products caused by loss of control and casualties accidentally heard, another drawback of the organization is water, oil, Into the dust, will use the friction coefficient change to cause the mechanism to fail, especially the dust into the difficult to control (non-metallic friction plate and metal materials generate static electricity, dust is easy to be adsorbed), so the emergence of new products after a few times and then release time The easy-to-use accidents, such as the use of non-metallic friction materials, are sensitive to temperature, and their friction coefficient changes with increasing temperature. The descending device is difficult to use. Working distance, over 30 meters prone out of control, using a centrifugal mechanism posture is also required to be hung vertically, or change in centrifugal friction pad gravity direction, an abnormal operation occurs, cause accidents, but also to flexibly and mounting strap Inconvenience. The advantage of this kind of descending device is that the processing cost is low. It can be manufactured by powder metallurgy. It can also be made of zinc-aluminum alloy, which is convenient for mass production. These metal materials have the disadvantages of low strength and high temperature.

Fourth, successful design case

CCTV ten, "I love the invention" 99 "Escape", "invention DreamWorks' September 19, 2013," I love the invention "January 19, 2018, shows several lifesaving developed by the Chinese military aviation engineer The constant-velocity descending device and the chain-typed community escape descending device are all adopting a new type of public institutions for slow-down control. The escape device parts are all made of alloy steel, with no fear of water, no fear of oil soaking, and no fear of dust pollution. With high temperature characteristics, it becomes a safe and reliable fire escape product. The constant speed descent device has no fixed installation posture and is quick and easy to use. Because it is made entirely of alloy steel, its safe storage period can be as long as 30 years. Therefore, when you plan to enter the field of development and production of high-rise fire escape products, you should not first calculate the economic benefits, but must evaluate your own professional knowledge, have the ability to produce and promote, and more importantly, must also have Responsibility for respecting the lives of others !

Author: from company commander to commander.