The principle, advantages and disadvantages of several liquid level gauges
First, the steel belt level gauge
Measuring principle: buoyancy principle. The floating plate moves up and down with the liquid level, and the length and the short pointer outside the can are rotated on the dial to indicate the liquid level.
Features: Measured pressure capacity, more accurate.
Disadvantages: The material and installation requirements of the steel strip are very high; in the case of frequent fluctuations in the liquid surface, the steel belt is broken by the guide wire ear hole, so that the steel strip is twisted once a year.
Safety: It is not safe to measure pressure, flammable, toxic, corrosive liquid.
Second, differential pressure level gauge
Measuring principle: The difference between the bottom of the liquid and the gas pressure above is measured. The pressure difference is equal to the weight of the liquid column, and the liquid level is calculated accordingly.
Features: High popularity.
1. The vapor phase capillary is easy to block;
2. The density value of the liquid should be measured in a timely manner so that the calculated liquid level accuracy is low.
3. The ratio of the pressure difference to the base pressure on the pressure vessel is small, and the pressure variation is a large error.
Safety: It is not safe to measure pressure, corrosion, toxic, and flammable liquids.
Price: low (high damage rate on pressure vessel)
Third, the glass plate level gauge
Measuring principle: Using the principle of the connected device, the liquid level is directly observed on the spot.
Features: The most original level gauge.
1. Labor frequently climbs high ladder to record figures, which is a waste of labor;
2, no remote transmission can not be connected with the automatic control system;
3. After using for a period of time, the glass plate becomes dirty and cannot be observed;
4. The glass plate may rupture and cause a major accident.
Safety: It is very dangerous to measure pressure, toxic, corrosive or flammable liquids.
Price: high (instrument, connected pipe valve, escalator, maintenance, labor, total cost of accident)
This article is from Allicdata Electronics Limited. Reprinted need to indicate the source.