No matter what kind of instruments and equipment, under some working conditions such as low temperature, high temperature, high pressure and low pressure, it is generally necessary to protect the components from damage. So what can be done in winter to protect the dynamic pressure sensor, make it operate normally and achieve good measurement results? Please note the following:
Dynamic pressure sensor is easy to freeze at low temperature in winter. The periphery of the dynamic pressure sensor may freeze, which may cause the housing or display to freeze. Secondly, if the air temperature is too low to a certain extent, the liquid at the pressure inlet may freeze. Once frozen, the volume will expand and squeeze the sensor, causing damage and affecting the measurement. So how to prevent freezing? Generally, the common measure for antifreeze of dynamic pressure sensor is heat tracing, including steam tracing or electric tracing. In fact, if the factor of low temperature in winter is considered in the field working conditions, the enclosure structure of thermal insulation device shall be considered in the selection.
1. Steam tracing, i.e. binding pipes, introducing steam or heating to achieve thermal insulation effect. Therefore, if there is steam tracing insulation pipe, check whether the steam or heating pipe is unblocked before insulation. When thermal insulation is required in winter, it is basically opened 24 hours, and the temperature of steam or heating is set according to the on-site ambient temperature.
2. The insulation device box is a box body wrapped with a dynamic pressure sensor, and the main insulation element is a heater. A socket will be installed on the side of the insulation box to facilitate the connection of power supply. However, a temperature controller needs to be added here. When the temperature in the box rises to the set temperature range, the temperature controller controls the power off. When the temperature drops to a certain value, control it to turn on the power and continue to rise. Generally, the electric heating pipe material of this heater can be divided into copper pipe, carbon steel pipe and stainless steel pipe. Stainless steel pipe is commonly used. Explosion proof heater is also required in some occasions.
3. New thermal insulation measures: the electric heating cable is actually a cable wound in contact with the instrument shell. When the power is turned on, the generated electric energy can be converted into heat energy, and then the heat energy is transmitted to the instrument shell through contact, so as to raise the temperature. Or stick the heating cable in the dynamic pressure sensor box.
In addition, if the anti freezing measures of the above dynamic pressure sensor are carried out manually, it is necessary to send someone to observe and adhere to the condition of the thermal insulation device or material every day. In case of damage, leakage or blockage, it shall be repaired or replaced in time to avoid greater loss. If there is no manpower and material resources, audible and visual alarm can be installed. For example, some gas detection and alarm devices can detect abnormal parameters and alarm if the insulation effect fails and the equipment is damaged. They can also alarm in time and repair or replace them immediately, so as to reduce losses.