Hydraulic static level settlement monitoring sensor-Global supplier

5-6F, Building 8, No. 115, Lane 1276, Nanle Road, Songjiang District, Shanghai (Chuangyi International Enterprise Park)

Static levelParameter characteristics

Rated range: 0-1500-2500-4000mmHg

Accuracy: 0.2mm~0.3mm

Model: SD-226

Static levelApplication principle

In use, the pressure measuring chambers of multiple static level gauges are connected in series to the liquid level container through liquid pipes, measured by high-precision silicon crystal core sensors, transmitted to the signal acquisition system through RS485 signals, and transmitted to the signal acquisition system through signal changes in the pressure monitoring process. Through analysis and calculation, they synchronously change with the changes in pressure measurement, thereby measuring the pressure changes at each measuring point and analyzing the relative settlement height of the ground surface.

Static levelProduct description

The SD-226 crystalline silicon liquid level transmitter consists of a reservoir, an imported high-precision core, a specially customized circuit module, a protective cover, and other components. Suitable for liquid level measurement with small measurement range and high accuracy. Mainly used for measuring the settlement of subway tunnels, building foundations, and dams.

Static levelProduct Usage

Static level is a high-precision liquid level measuring instrument used to measure the relative settlement of various measuring points in foundations and buildings. Application sites include large buildings such as hydroelectric power plants, dams, high-rise buildings, nuclear power plants, water conservancy hub projects, and the measurement of uneven settlement at various measuring points such as railways, subways, and high-speed railways

Static levelOverall Dimension Drawing

The application impact of static level:

Possible impacts of this product in application (briefly introduce railway dynamic examples):

Due to their own weight, rail transit trains generally generate instantaneous airflow and vibration during operation, resulting in significant measurement errors in the product during or after a period of time. The following examples illustrate:

a. The variation of air pressure inside the instrument

For example, the operation of the subway causes air flow inside the tunnel, leading to a decreasing trend in air pressure inside the static level container and an upward trend in liquid level. This results in a small amount of air appearing inside the testing instrument after a long period of time, affecting measurement accuracy (this product is equipped with an exhaust valve, which can perfectly solve this problem).

b. The impact of train vibration

When the train carriage is located near the monitoring point, the monitoring point sinks, causing the liquid level in the static level container to rise; After the train moved away from the monitoring point, the monitoring point lifted up, causing the liquid level in the static level container to drop. The instantaneous passing of the train will cause the liquid level of the container to vibrate up and down, resulting in fluctuations in the pressure inside the pressure measuring chamber of the monitoring product (this product has a fast recovery speed).

c. The influence of benchmark points

When the train passes through the reference point, it will cause two effects, a and b, on the reference point, which will be transmitted to the monitoring point with opposite effects

Introduction to the Development of Settlement Monitoring Equipment on Railways

Main purpose of railway settlement monitoring

1. Obtain observation data on the load and natural settlement of the newly built 200-350km/h ballastless track subgrade.

2. By monitoring, obtain the true situation and deformation trend of settlement and deformation of different structures in the project.

3. By monitoring and understanding the dynamic changes in settlement during the compaction process of the roadbed, timely and reliable information can be provided for the later settlement assessment, in order to evaluate the safety of the foundation of the ballastless track under load and natural settlement.

4. Provide forecasts for potential safety hazards in engineering, in order to take effective measures and prevent accidents from occurring.

Precautions before installation

1. The requirement for the selection of base points before installation is that the distance between the base point principle measuring points should be as stable as possible, with a distance of more than 1m and no interference from vibration sources. The drop shall not exceed 1.5m. The spacing between measuring points shall be arranged according to the design requirements.

2. Before installation, confirm the ID address of the sensors and record it in the PC software. Test all the sensors to be installed online for 10 minutes. During installation, determine the sensors according to the order of ID numbers and measurement point positions.

Connection method of connecting pipes

3. The measuring point sensor is fixed and installed with expansion bolts, and it is required to be firmly fixed. Then, the liquid connecting pipe is connected in series to each measuring point sensor. The base point and the liquid storage tank are connected and closed, and the screw at the liquid interface is locked and fixed without leakage.

4. The pressure balance pipe is connected in series using the same connection method as the liquid connection pipe, and then connected to the base point and the liquid storage tank.

Connection method of sensor signal line:

5. The connection of communication cables adopts twisted pair shielded PU4 * 0.4 anti slip cables, with colors divided into white signal blue signal+black 12v - red 12v+connected to the junction box according to the color of the cable. The connection method adopts the series connection of blue measuring point base for communication, and then connected to the acquisition instrument.

6. The requirements for liquid addition vary depending on the monitoring environment. Two types of liquids are recommended. The first type is tap water or distilled water. Generally, when using this type of liquid, it is necessary to ensure that the ambient temperature change is not greater than 10 degrees and that the expansion coefficient of the liquid is within the control range to prevent freezing.

7. Antifreeze+tap water, 1:1 ratio. This liquid is generally used in cold northern regions with a temperature range of -20 ° -30 ° C. The main purpose is to prevent liquids from freezing up.

8. The addition of liquid is done through a storage tank. When adding liquid, the valve of the rear measuring point sensor should be opened to ensure that air can be discharged. When adding liquid, it should be ensured that there are no bubbles in the connecting pipe and sensor as much as possible. The diameter of the bubble should not exceed 2mm. This ensures a more stable phase for the sensor. The method of expelling bubbles can be achieved by pressing down the valve.