What Is a Temporal Lift?
Construction elevators are often called construction elevators, but construction elevators include a broader definition, and construction platforms also belong to the construction elevator series. The simple construction elevator is composed of a car, a driving mechanism, a standard joint, an attached wall, a chassis, a fence, and an electrical system. It is a frequently used construction machinery for people and goods. It is comfortable and safe to ride. Construction elevators are usually used in conjunction with tower cranes on the construction site. The general load capacity is 0.3-3.6 tons and the running speed is 1-96M / min. The construction hoist produced by our country is becoming more and more mature, and gradually goes international.
- The failures of construction elevators are generally divided into two categories, namely electrical failures and mechanical failures. The two types of failures are handled differently, [5]
- Speed limiter
- A safety device installed to prevent the speeding or falling of the cage of the construction elevator is divided into two types: one-way and two-way. It can act as a speed limit along the up and down directions of the cage. The speed limiter shall be tested for performance within the prescribed period.
- 2.Buffer spring
- The buffer spring is installed on the spring seat connected to the base frame, so as to reduce the impact of the hanging cage when the hanging cage falls, and at the same time ensure that the hanging cage and the counterweight fall into a flexible contact when the hanging cage and the counterweight fall to the ground Shock. There are two kinds of buffer springs: conical coil spring and cylindrical coil spring. Generally, there are two or three conical coil springs or four cylindrical coil springs on the corresponding chassis of each hanging cage.
- 3.Upper and lower limiter
- The device is installed on the cage and the guide rail to prevent accidents caused by the cage from exceeding the required stop position when it is moved up or down, or due to accidental operation by the driver and electrical faults. It is installed on the cage and the guide rail. The block and limit switch are composed of the highest limit device on the top of the cage to prevent the roof from falling; the lowest limit device on the bottom of the cage can accurately stop the floor and belongs to the automatic reset type.
- 4. Upper and lower limit stops
- The upper and lower limit stops are when the upper and lower limit stops are ineffective. When the cage runs beyond the limit switch and overtravel, the power can be cut off in time to stop the cage. The limit position is non-automatic reset type. The cage can only be restarted after manual reset. The limit stop is installed on the hanging cage and the rail frame. (Overtravel refers to the specified safety distance between the limit switch on and the limit switch)
- 5. Safety hook
- The safety hook is to prevent the hanging cage from reaching the preset position. The upper limit stop and the upper limit stop cannot move in time due to various reasons. The hanging cage continues to run upward, which will cause the hanging cage to impact the top surface of the guide rail frame. The hook block is the last safety device. It can make the cage go up to the top of the rail frame safety protection facilities, and it can be safely ditched on the rail frame to prevent the cage from derailing and ensure that the cage does not fall over.
- 6.Emergency stop switch
- When an emergency situation of various reasons occurs during the operation of the cage, the driver can press the emergency stop switch at any time to stop the cage. The emergency stop and quick close must be a non-self-resetting safety device, which is usually installed on the top of the hanging cage.
- 7.Hanging cage door, protective fence door interlocking device
- The elevator door and the protective fence door of the construction elevator are equipped with electrical interlock switches, which can effectively prevent the fall of personnel materials caused by the startup operation of the cage or the protective fence door. Only when the cage door and the protective fence are completely It cannot be started until it is closed.
- 8. Floor access door
- A passage for material transportation and people in and out is provided between the construction elevator and the floor, and a floor access door must be provided at the junction of the passage entrance and the construction elevator. The height of the access door on the floor is not less than 1.8m, and the lower edge of the door should not exceed 50mm from the access surface. This door is normally closed when the cage is running up and down, and can only be opened by the personnel in the cage when the cage is docked. The door on the floor should not be opened to ensure that the entrance of the passage is not dangerous under closed conditions.
- 9. Communication device
- Because the driver's operating room is located in a hanging cage, it is impossible to know the demand situation of each floor and it is unclear which floor sends a signal, so a closed-circuit two-way electrical communication device must be installed. The driver should be able to hear the demand signal on each floor.
- 10. Protective shed at the ground entrance
- When the construction elevator is completed, a protective shed at the ground entrance should be erected in time. The material used for the protective shed should be ordinary scaffolding steel pipes, and the length of the protective shed should not be less than 5m. It can be connected with the protective shed of the ground passage if possible. The width should not be less than the outermost dimension of the elevator bottom cage. The top material can be 50mm thick wooden boards or two-layer bamboo fences, and the spacing between the upper and lower bamboo fences should be not less than 600mm.
- 11. Broken rope protection device
- When the ropes of the suspension cage and the counterweight are broken, the broken rope protection switch cuts off the control circuit and the brake is stopped. [2]
- Construction elevator is a kind of dangerous equipment, which can easily lead to serious casualties.
- 1. Installation and disassembly of construction elevator:
- Contract the assembly and disassembly of the construction elevator to teams or individuals without corresponding qualifications for assembly and disassembly;
- Do not construct according to the construction elevator installation and disassembly plan or no installation and disassembly plan at all, even if there is a plan, it is not targeted, and it lacks the necessary approval procedures, and there is no unified command by the person during the disassembly process;
- The construction elevator is put into use immediately after the installation is completed. It does not perform the relevant acceptance procedures and necessary test procedures, and does not even report to the professional testing agency designated by the local construction administrative department for testing, resulting in mechanical, electrical failures and various accidents;
- Assembly and dismantling personnel are on the job without professional training;
- The detailed and targeted safety technology has not been delivered before the assembly and disassembly operation, and the necessary monitoring measures are lacking during the operation. Violation operations on the site can be seen everywhere, and major accidents such as falling from height and hurting people are extremely easy to occur.
- 2. The safety device is improperly installed or not installed, which makes the safety device fail when the hanging cage fails during operation.
- 3. The floor door is not in compliance with the requirements, and the net height of the floor door is low, so that some materials carriers stick their heads out of the door to observe the operation of the hanging cage. Some floor doors can be opened from inside the floor, making the entrance of the entrance a dangerous front door, causing accidents due to personnel fall or material fall.
- 4. The driver of the construction elevator does not have a license to work or the driver has not turned off the power when leaving the cab, so that undocumented personnel have the opportunity to start the elevator without authorization. If you are at a loss when you encounter an unexpected situation, it will lead to an accident.
- 5. Do not control the number of personnel and material weight according to the rated load of the elevator, which will cause the elevator to be overloaded for a long time, which will cause deformation of the hanging cage and other stressed components, which brings serious hidden dangers to the safe operation of the elevator.
- 6. Do not configure the counterweight in time according to the design requirements, and do not halve the rated load, which is extremely detrimental to the safe operation of the elevator.
- 7. The speed limiter fails to perform a drop test every 3 months as required. Once a stall stall occurs, a failure of the speed limiter will have serious consequences.
- In addition, metal structures and electrical metal enclosures that are not grounded or grounded do not meet safety requirements, the safety factor of steel wire ropes for hanging weights is less than 8 times, and phase sequence and power-off protectors are not provided for electrical installations. Accidents are common. [5]
- Construction elevators are common construction equipment. They vertically lift and move people or materials in a large area. They are construction machinery with a high probability of accidents. With the continuous and rapid growth of China's economy and the continuous expansion of urban construction, the production and sales of construction elevators have grown rapidly. The increase in construction sites and the increase in the difficulty and complexity of construction have led to more and more serious safety issues. Although our country spends a lot of manpower and material resources to carry out supervision every year, due to the wide location, complicated situation and insufficient comprehensive detection, the effectiveness of manual supervision is reduced. Therefore, how to comprehensively and efficiently manage the safety of the construction elevator equipment and ensure its safe operation is an urgent problem to be solved. [5]
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
|
|
| |
|
|
|
- [4]
- The content of Baidu Encyclopedia is edited by netizens. If you find your entry is inaccurate or incomplete, you are welcome to use my entry editing service (free of charge) to participate in the correction. Go Now >>