How to prevent freezing of pressure transmitters in winter

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People say that it’s necessary to take care of level gauges in winter – but do pressure transmitters also need protection in winter? Of course, answers are needed. For any type of instrumentation or equipment, under special operating conditions such as low temperatures, high temperatures, high pressures, or low pressures, it is generally necessary to take care to prevent damage to the key components. So, what can be done in winter to protect pressure transmitters and ensure they operate properly for accurate measurements? Please note the following points: In winter, low temperatures can lead to freezing. Firstly, ice may form around the pressure transmitter, which can damage its casing or display screen ； Secondly, if the temperature drops low enough, the liquid inside the pressure tapping may freeze; once it freezes, its volume expands, which can press on the sensor and cause damage, thereby affecting the measurements. So how do you prevent freezing? The common measure used to prevent freezing of instruments is heating, either with steam or electric heating. In fact, if the operating conditions on site take into account the low temperatures in winter, then insulation enclosures should be considered when selecting the appropriate equipment. 1. What is steam tracing? It refers to the use of pipes, with steam or heat being supplied to them in order to achieve insulation effects. Therefore, if steam insulation pipes are used, it is necessary to first check whether the steam or heating pipelines are unobstructed before applying insulation. During winter, when insulation is required, these pipelines are usually kept operational 24 hours a day, and the temperature of the steam or heat is set according to the ambient temperature at the site. 2. What is a thermal insulation device box? It is a box that encloses the pressure transmitter; the main thermal insulation element is a heater. A socket will be installed on the side of the insulation unit box to facilitate power connection. However, a temperature controller needs to be added here; when the temperature inside the box rises to the set range, the temperature controller controls the power to be cut off ； When the temperature drops to a certain value, it controls the power to be turned on to continue raising the temperature. Under normal circumstances, the material of the electric heating element in this heater can be copper tube, carbon steel tube, or stainless steel tube; stainless steel tube is commonly used. In some cases, an explosion-proof heater is required. 3. Insulation measures for Type 3: An electric heating cable essentially consists of a cable that is wrapped around the instrument housing; when power is supplied, the electrical energy generated is converted into heat energy, which is then transferred to the instrument housing through contact, thereby raising its temperature. It is also possible to attach the heating cable inside the instrument panel. Friendly reminder: For the above anti-freezing measures, if manpower permits, it is necessary to assign someone to regularly check the condition of the insulation devices or materials on a daily basis. Any damage, leakage, or blockage should be repaired or replaced promptly to avoid greater losses. If there is no manpower but physical resources are available, an audio-visual alarm can be installed. For example, in some gas detection alarms, if the insulation function fails and the device is damaged, resulting in gas or liquid leaks, it can detect when the parameters exceed the normal range and issue an alarm. This allows for timely alerts, enabling immediate repairs or replacements in order to minimize losses.