All Question of elevator shaking

There are various causes of elevator shake and vibration, which may be caused by certain component failure, or it may be caused by changes in the overall performance of the system or even the combined effect of the two.

Shanghai DOBY Smart collected the reasons for the elevator shake and vibration.

一、 The Mechanical parts

1. caused by elevator car guide rail or counterweight guide rail

The installation of the guide rail should meet the requirements: the relative maximum deviation between the measured values of each 5m plumb line of the working surface of each row of guide rails, the car guide rail and the T-type counterweight guide rail with safety gear not greater than 1.2mm, and the T without safety gear Type counterweight guide rail is not more than 2.0mm; if the main and auxiliary guide rails are not vertical when installed or used for a long time, the wear and deformation of the rail surface will cause the rail joints to be misaligned, and the gap will be too large for the two working surfaces. Without adjustment and maintenance, the guide rail face is distorted, and the guide rail is severely worn, which can cause shacking and noise when the car is running.

2. The guide rail bracket is loose or the rail screws are loose.

Each guide rail should have at least 2 guide rail brackets, and the spacing is generally not more than 2.50m (if the spacing is greater than 2.50m, there should be a calculation basis). The number of brackets at the end of the short guide rails should meet the design requirements; Welds meet the design requirements. Anchor bolts (such as expansion bolts) can only be used on the concrete components of the shaft wall; when the guide rail bracket is loose or the pressure rail screws are loose, it will cause the guide rail to intensify wear during the elevator operation. Less than required, resulting in Shaking and noise during elevator operation.

3. The guide rails distance has a large error

The deviation of the distance between the top surfaces of the two rows of guide rails is 0 ～ + 2mm for the car guide rails and 0 ～ + 3mm for the counterweight guide rails. When the distance of the guide rails fails to meet the standard requirements, the horizontal swaying during the elevator operation will be aggravated, which will cause Shaking and noise.

4. Poor vibration reduction of the traction machine base produces

The fixing bolts of the traction machine are loose or the damping ring is loose, the fixing bolts are loose, the car shakes and shakes during the elevator operation, and one damping rubber ring is dropped. The three rubber rings support the host on the same plane. Under the action of machine traction, the elevator generates periodic shaking.

5. The inconsistent gap between brake shoe and brake

The gap between the two sides of the brake car is uneven. When running, it does not rub when it is rubbed, and the worn brake pads are inconsistent in the arc. Friction with brake shoes during unilateral gap-free movement will cause car shake.

6. Traction machine has a problem

In the gearbox, the clearance between the worm gear and the worm is not good or the grinding is not good. The bearings in the traction machine or gearbox are not good. Traction machine is damaged due to the shaft pump or severely worn due to the traction machine. The guide has a larger gap than the bearing. The traction machine or the guide is more imbalanced than the shaft. Periodic vibration excitation generates an elevator running shaking.

7. Car guide shoe wear

The car guide shoes are severely worn, the uneven load on the heavy-duty operation causes friction, and the guide rails cause the car to shake. Or due to improper adjustment of the gap of the guide slider, improper adjustment of the parallelism of the guide slider, too much or too little expansion and contraction of the guide slider, shaking may occur.

8. Uneven tension adjustment or inconsistent spring compression at the fixed end

When the wire rope torque is not released, the wire rope pulling force cannot be adjusted, and the wire rope pulling force is uneven. Exceeding the national standard, it is easy to cause the wear of the traction sheave. The slippage of the wheel increases, and the vibration of the wire rope increases.

9.Compensation chain and compensation rope scratch caused by car shake

The compensation chain and the compensation rope are incorrectly mounted on the counterweight frame, or stretched too long, and scratched to other parts in the hoistway, causing abnormal noise.

10. Traction wheel rope groove wear is deformed and uneven

The traction sheave groove is severely worn, which will cause uneven tension of the wire rope and uneven traction speed, which will cause the elevator to vibrate.

11. The Steel rope has broken strands or the wire rope is severely broken.

When the traction rope has broken strands, friction between the broken stranded wire rope and the baffle plate will generate a huge sound, or it will interfere with other steel ropes, resulting in unstable elevator operation.

12. Bearings of anti sheaves worn

When the bearings on the car top anti sheaves or counterweight anti sheaves are worn, the elevator feels like a meal when running at high speed.

13. Car wall, car bottom, car top screws are loose

When the elevator is running at a high speed, the car must withstand a large force. If a certain part of the car frame or the car wall is not fastened, when the elevator is running at a high speed, the part is likely to cause relative displacement, which will cause the elevator to move. vibration.

14. Traction rope needs to be added with a shock absorption device

The method of eliminating the vibration of the steel wire rope is to clamp several steel wire ropes at a position of 300 to 500 mm above the rope rod rope head to improve the resonance, or use an iron plate with a length of about 1000 mm and a thickness of 10 mm to punch holes according to the arrangement of the wire rope. The upper or lower end of the steel wire rod fixes several steel ropes to the iron plate first and then adjusts the weight of the balanced iron blocks at both ends of the iron plate to obtain the optimal state to eliminate resonance, reduce the vibration amplitude of the rope, and improve comfort.

15. Distortion of counterweight frame

Due to the poor stacking of parts, the counterweight frame is directly installed after being distorted and deformed. If the counterweight plate is not installed properly, the counterweight will not be fixed, and it will cause shaking or abnormal noise.

16. Small safety gear clearance

After the safety gear is activated, the cymbal block is not completely reset, and the track is ground during operation.

17. The Block in the hoistway

During counterweight operation, it collided with another objects in the hoistway and transmitted to the car, causing vibration.

18. Closed well without ventilation

Generally, the elevator shaft of the machine room is completely closed, and the ventilation airflow is all in series from the door seam and the wire rope hole in the machine room. It is recommended to set a vent on the top of the elevator shaft for the high-speed elevator shaft. Because if the net area of the hoistway is small, the hoistway is well closed, and the door gap of the elevator installation hall is small, there will be a large airflow when the elevator runs, which will easily cause the elevator to vibrate or shake.

19. Car balance problem

The car's dynamic balance and static balance are not well prepared. Static balance is to stop the elevator on the bottom floor, remove the car bottom guide shoes, and see if the car is tilted. Dynamic balance causes the guide shoes to tightly guide the guide rail surface when the elevator is running. There will be shaking or vibration. Large differences in balance coefficients can also cause poor comfort or shaking during elevator operation.

二、 The Electric Parts

First: The brake circuit can not be opened or cannot be opened completely due to poor contact of the upper and lower running contacts of the brake circuit or loose wiring.

Second: The traction torque of the traction machine fluctuates, and the torque is poorly adjusted at start-up. If the torque is too small, reverse pulling occurs. If the torque is too large, the car will shake.

Third: The impedance of the main drag circuit is not adjusted well, and the shaking is abnormal when running at a slow speed.

Fourth: The speed-measuring generator is faulty and the feedback is unstable.

Fifth: The feedback adjustment of the DC elevator magnetic cabinet is unstable, and there is a zero floating phenomenon.

三、 The quality of Elevator

1. Poor bearings of the host traction sheave and guide sheave cause shaking

The bearing clearance of the main engine traction wheel and guide wheel is large; the dynamic balance between the traction wheel and the guide wheel itself is poor; the bearing in the traction machine or gear box is bad; when the concentricity between the worm and the motor shaft of the traction machine is too poor Periodic vibration excitation may occur, causing elevator operation shaking. Therefore, firstly, the product quality and assembly quality of the traction sheave and the guide wheel should be improved, and the bad bearings should be replaced in time to eliminate the periodic excitation source.

2. The vibration of the base rubber of the host base is bad, causing shaking.

The base of the host is generally supported by 4 pieces of vibration-damping rubber. Due to the difference in steel and resistance, it is easy to form 3 pieces of rubber to support the host on the same plane. Periodic shaking occurs under the traction force of the traction machine. At this time, the deformed vibration-damping rubber should be replaced, so that 4 pieces of rubber support the host together on the same plane, so as to achieve a good vibration-damping effect.

3. The stiffness of the strong head spring causes shaking

The different stiffness of the rope head spring is manifested in the different elasticity of the spring under the same compression amount. The rigidity of the rope head rod spring must be moderate and match its load capacity. The vibration damping effect of too large or too small stiffness is not good.

四、The elevator installation is not good

1. Shake caused by poor installation of elevator guide rails

The poor installation of the elevator guide rails mainly includes the verticality, spacing of the guide rails, the joints of the guide rails, and the steps of the joints that exceed the national standard. The fixed expansion screw on the guide rail bracket and the screw of the pressure guide plate of the guide rail are loose; the connection gap between the guide rail bracket and the guide rail base is too large or the two working surfaces are seriously out of parallel. Poor product protection during installation caused partial distortion of the guide rails, pits on the working surfaces of the guide rails, or welding scars, which can generate vibration and noise when the car is running up and down.

2. caused by poor car assembly

The bad assembly of the car mainly includes the poor level of the car bottom, which causes the car's center of gravity to shift and the static balance to be poor. The center of the traction sheave groove and the center of the car are not on the same straight line, and the deviation is large, causing the swing vibration of the car. To improve the shaking caused by poor car assembly, the distortion of the car frame should be confirmed after removing the upper guide and the car is in a free state. The error should be adjusted to within 5mm, and then the level of the car bottom should be confirmed. 2. The verticality of the car and careful static balance of the car can better eliminate the impact of the guide shoe on the guide rail.

3. Shake the distortion of the heavy frame

Due to the poor stacking of parts, the counterweight frame is directly installed after being distorted and deformed. If a single compensation chain or a compensation chain is incorrectly mounted on the counterweight frame, it will cause shaking or abnormal noise.

五、 The Elevator Commission not ready

1. caused by improper adjustment of the elevator guide gap

Improper adjustment of the guide slider gap, improper adjustment of the parallelism of the guide slider, and too much or too little expansion and contraction of the guide slider cause shaking. The amount of expansion and contraction of the guide shoe is generally 3mm on each side to better absorb the shock excitation from the guide rail.

2.caused by uneven torsion and tension of wire rope

When the wire rope torque is not released, the wire rope pulling force cannot be adjusted, and the wire rope pulling force is uneven. Exceeding the national standard, it is easy to cause the wear of the traction sheave. The slippage of the wheel increases, and the vibration of the wire rope increases. The method of eliminating the vibration of the steel wire rope is to clamp several steel wire ropes at a position of 300 to 500 mm above the rope rod rope head to improve the resonance, or use an iron plate with a length of about 1000 mm and a thickness of 10 mm to punch holes according to the arrangement of the wire rope. The upper or lower end of the steel wire rod fixes several steel ropes to the iron plate first, and then adjusts the weight of the balanced iron blocks at both ends of the iron plate to obtain the optimal state to eliminate resonance, reduce the vibration amplitude of the rope, and improve comfort.

3. Poor electrical adjustment

The fluctuation of the main engine traction torque is the excitation source of the elevator vibration. The torque is improperly adjusted at startup, the reverse tension occurs when the torque is too small, and the advance occurs when the torque is too large. When you stop, you adjust too quickly, as if you are sitting in a car and experience a sudden brake. Improper feedback adjustment can also generate self-excited oscillations. By adjusting the torque or acceleration curve at the moment of starting, can be reduced and starting comfort is improved.

Shanghai DOBY Smart Equipment Co., Ltd