A pressure transmitter is an instrument that accepts pressure variables, converts them into standard output signals in a certain proportion after sensing and conversion. The output signal of the transmitter is transmitted to the central control room for pressure indication, recording, or control.

So how should we maintain it in our daily use? Below is an explanation for you:

1. Check the size of the installation hole: If the size of the installation hole is not appropriate, the threaded part of the sensor is easily worn during installation. This not only affects the sealing performance of the equipment, but also prevents the pressure sensor from fully functioning, and may even pose safety hazards. Only suitable installation holes can avoid thread wear, and installation hole measuring instruments can usually be used to detect installation holes and make appropriate adjustments.

2. Keeping the installation holes clean: Keeping the installation holes clean and preventing melt blockage is crucial for ensuring the normal operation of the equipment. Before cleaning the extruder, all pressure sensors should be removed from the barrel to avoid damage. When dismantling the sensor, the molten material may flow into the installation hole and harden. If these residual molten materials are not removed, it may cause damage to the top when reinstalling the sensor. The cleaning kit can remove these residual molten materials. However, repeated cleaning processes may deepen the damage caused to the sensor by the mounting holes. If this situation occurs, measures should be taken to raise the position of the sensor in the installation hole.

3. Choosing the appropriate location: When the installation position of the pressure sensor is too close to the upstream of the production line, unmelted material may wear down the top of the sensor; If the sensor is installed too far back, there may be a stagnation zone of molten material between the sensor and the screw stroke, where the molten material may degrade and the pressure signal may be distorted; If the sensor is too deep into the barrel, the screw may touch the top of the sensor during rotation and cause damage. Generally speaking, sensors can be located on the barrel in front of the filter screen, in front and behind the melt pump, or in the mold.

4. Carefully clean; Before cleaning the extruder barrel with a wire brush or special compound, all sensors should be removed. Because both cleaning methods may cause damage to the sensor's diaphragm. When the barrel is heated, the sensor should also be disassembled and the top should be wiped with a soft cloth that will not cause wear. At the same time, the holes of the sensor need to be cleaned with a clean drilling machine and guide sleeve.

5. Keep dry: Although the circuit design of sensors can withstand harsh extrusion processing environments, most sensors are not absolutely waterproof and are not conducive to normal operation in humid environments. Therefore, it is necessary to ensure that the water in the water cooling device of the extruder barrel does not leak, otherwise it will have adverse effects on the sensor. If the sensor has to be exposed to water or humid environments, a special sensor with strong waterproof properties should be selected.

6. Avoid low temperature interference: During the extrusion production process, plastic raw materials should have sufficient "soaking time" from solid to molten state. If the extruder has not reached the operating temperature before starting production, both the sensor and the extruder will be damaged to a certain extent. Additionally, if the sensor is removed from the cold extruder, the material may adhere to the top of the sensor, causing damage to the diaphragm. Therefore, before removing the sensor, it should be confirmed that the temperature of the barrel is high enough and the material inside the barrel is in a softened state.

7. Preventing pressure overload: Even if the overload design of the pressure sensor's measuring range can reach up to 50% (the ratio exceeding the maximum range), from the perspective of equipment operation safety, risks should be avoided as much as possible, and it is best to choose sensors with measured pressure within the range. Under normal circumstances, the optimal range of the selected sensor should be twice the measured pressure, so that even if the extruder operates at high pressures, the pressure sensor can be protected from damage. The pressure transmitter is required to be inspected once a week and once a month, mainly to remove dust from the instrument, carefully check the electrical components, and regularly calibrate the output current value. The pressure transmitter has weak electricity inside and must be isolated from external strong electricity.

The above content is the relevant information about pressure transmitters that we will share with you this time. We hope that after reading it, you can have a better understanding of the product.