Will the wire rope that pulls the elevator suddenly break? Will the elevator suddenly fall and hit the ground? Trapped in the elevator, do you want to open the door and come out as soon as possible? ... In recent years, elevator safety incidents have caused panic among citizens and attracted considerable attention. Liu Yuejin, director of the inspection department of Wuhan Special Equipment Supervision and Inspection Institute, revealed some cold knowledge about elevator safety.
Elevator falls are not so scary
Many people worry that the elevator will suddenly fall during operation and finally hit the ground. But in fact, although "elevator falling" is a kind of failure often encountered, but the elevator does not really fall.
"Elevator falling" may be caused by the disconnection of the safety circuit or the door lock circuit during the elevator operation, resulting in an emergency stop of the elevator. It may also be that the elevator fails during operation and automatically returns to the base station to reset.
"Without the normal opening and closing of doors, these small faults have accumulated. The elevator restarts itself like a computer, and automatically returns to the bottom base station to reset. At this time, the buttons inside the elevator are invalid and cannot be opened, and the elevator falls slowly at a slower speed than normal. However, because there is no stopping floor, people inside the elevator mistakenly believe that the elevator is trapped, and the fault falls directly. In fact, this is the elevator's safe response to the fault." Liu Yuejin said.
Freight Elevator are not as fragile as you think
In fact, elevators have many safety devices, which are guaranteed by multiple levels of control. The first is the professional traction wire rope with very good toughness, followed by the emergency stop switch on the top of the machine room and the car, as well as the mechanical and electrical interlocks on the doors of each floor. In addition, the top and bottom of the hoistway have limited position, limit and speed limit. A switch that prevents the car from continuing to move when the elevator reaches the top or squats to the bottom. When the elevator speed is abnormal, the speed limiter will trigger the safety gear to clamp the guide rail to prevent it from falling. Finally, an oil pressure buffer is also installed in the elevator pit to ensure that it will not directly hit the ground when falling.
Therefore, the elevator accident fatality rate is only 0.11 per 10,000 units, far less than the traffic safety accident fatality rate. Moreover, most elevator accidents are caused by human factors. For example, during installation and maintenance, there is no safety warning, and they fall into the well without paying attention.
Beware of these actions causing elevator accidents
Summer is approaching, and comfortable and breathable sneakers and slippers are standard for many people. Liu Yuejin reminded that the frictional resistance between these shoes and the pedals of the escalator is very large, which may cause the foot to be unable to lift the foot in time and cause a safety accident.
When renovating new houses, many owners will directly transport materials such as slabs, sand and gravel by passenger elevators, causing the elevators to be overweight. There are also people blocking the elevator door with things to facilitate the carrying of things. If the elevator is used incorrectly in this way, it is easy to cause elevator failure and reduce the service life of the elevator.
In the event of an elevator failure, Liu Yuejin reminded him to wait for professionals to come to rescue, and wait for the elevator car to be stabilized before getting out. Do not force the door to open the door, which will cause a second accident.