stainless steel diaphragm pressure gauges

Stainless steel diaphragm pressure gauges are used to measure the pressure of media with strong corrosion, high temperature, high viscosity, easy crystallization, easy solidification, and solid floating substances. It is necessary to avoid direct entry of the measuring medium into general-purpose pressure instruments and to prevent sediment accumulation and easy cleaning. A diaphragm gauge consisting of a diaphragm isolator and a general-purpose pressure instrument should be used.

Definition of diaphragm pressure gauge

Due to the fact that the diaphragm pressure gauge system is filled with sealing fluid as the medium for transmitting pressure, the temperature expansion coefficient of the sealing fluid causes the reading of the pressure gauge to increase as the temperature of the pressure part increases. The temperature influence is related to the expansion coefficient of the sealing fluid, the stiffness of the diaphragm, and the temperature of the pressure part, especially for low range pressure instruments, the influence is more significant. The temperature error of the compressed part is generally not greater than 0.1%/℃. Therefore, the total temperature impact of diaphragm pressure instruments is generally the sum of the temperature impact of universal instruments and the temperature impact of the pressure part of the diaphragm device.

Characteristics and uses

The gas density relay is a vibration resistant type with integrated indication and control, high precision, high safety, high reliability, good sealing performance, and strong environmental adaptability. It provides a novel detection and control instrument for the safe operation of high-voltage electrical equipment in the power industry.

Stainless steel diaphragm pressure gauges are mainly used to measure the pressure of fluid media in industrial sectors such as petrochemicals, alkali production, chemical fibers, dyeing, pharmaceuticals, food, and refrigeration.

Structural Principles

When the pressure P of the measuring medium acts on the diaphragm, the diaphragm undergoes deformation and compresses the sealing fluid of the pressure measuring system of the pressure instrument, forming a pressure state of P - △ P. When the rigidity of the diaphragm is small enough, Δ P is also very small, and the pressure formed by the pressure gauge pressure measurement system is close to the pressure of the measuring medium. The controller consists of a density detection system and a contact device.

The pressure measurement method with temperature compensation is adopted to detect and control the pressure value corresponding to a certain density value of SF6 gas in sealed containers, achieving the purpose of gas density monitoring

In a sealed container, the pressure value of SF6 gas at a certain temperature (20 ℃) can be regarded as the gas density value at that temperature (20 ℃). We take the gas pressure value at 20 ℃ as the representative value of its corresponding density and use it as a scale value. When the ambient temperature changes, the temperature compensation element compensates for the gas pressure change caused by temperature changes. Therefore, as long as the SF6 gas density remains unchanged, the indicator value of the relay also remains unchanged

The density detection system consists of sensitive components, transmission mechanisms, temperature compensation components, and indicator devices. When the gas density changes, the displacement of the sensitive element is converted into an indicator value through the transmission mechanism. When the environmental temperature changes affect, compensation and correction are carried out by temperature compensation components.

When the SF6 gas density drops to a certain set value, the contact device immediately sends out an alarm and locking control signal correctly and reliably according to the pre-set value to ensure the normal and safe operation of high-voltage electrical equipment.