Melt pressure sensor in the installation and maintenance of plastic machinery
in the Chinese building materials extrusion production line, high-temperature melt pressure sensors to improve melt quality, improve production safety and the protection of production equipment and other aspects play an important role. Meanwhile, melt pressure transducer is very sensitive element, only the appropriate installation and maintenance in order to make the role into full play. In the extrusion process, the product of some quality standards (such as dimensional accuracy or surface roughness added mineral filler parts, etc.) are required to optimize extrusion pressure control, g melt pressure transducer to achieve this important elements required. By setting the melt pressure sensor and a pressure control device in a mold inlet connection, enabling more stable yields, while reducing material waste. Melt pressure sensors to improve melt quality, improve safety and protect the equipment and extend its service life and other aspects of production plays an important role. In addition, measurement of pressure through the filter and melt pump to ensure production safety and optimize the performance of equipment is also very important. If the melt into the mold is blocked, the following screen prompts sensor will alert the operator. When the sensor upstream of the filter alarm, indicating that the internal extruder pressure is too high, may cause excessive wear of the screw. For the application of the melt pump manufacturers, the need to measure the inlet pressure and outlet pressure of the melt to ensure that the melt can be continuously flow into the mold, since any impediment may cause damage to a melt pump. In the extrusion production line assembly melt pressure sensor can be measured only a single point pressure sensor can also be used to measure a series of the entire production line of sensors. Melt pressure sensor and data logger, voice alarm device connected to the use of process control systems can adjust machining parameters of the extruder. At the same time, the pressure sensor is very sensitive element, if not the correct installation and maintenance, it is very easy to damage. Here are a few simple way to help extend the life of the pressure sensor, and can help users get accurate and reliable measurement results. ● properly installed damage is usually melt pressure sensors are due to improper mounting position caused. If the sensor is installed in the force is too small pores or irregularly shaped holes, it may cause vibration sensor film impact damage. Select the appropriate tooling mounting holes, help control the size of the mounting holes. In addition, proper installation torque is conducive to the formation of a good seal. However, if the installation torque is too high, it is easy to cause slippage melt pressure sensors, in order to prevent this from happening, usually before the sensor is mounted on the threaded portion of the application of its anti-off compound. After the use of this compound, even with high torque, the sensor is difficult to be moved ● Check the size of the mounting hole dimensions of the mounting holes if inappropriate, melt pressure sensor in the installation process, which is very vulnerable to a threaded portion wear. This will not only affect the sealing performance of the device, and the sensor is not functioning well, and may even produce a security risk. Only appropriate mounting holes to be able to avoid wear and tear thread (thread industry standard 1 / 2-20UNF2B), usually using the mounting holes on the mounting holes measuring instrument for testing, in order to make appropriate adjustments. ● Keep the mounting hole clean to keep clean and prevent the mounting hole jam melt ensuring the normal operation of the equipment is very important. Before the extruder to be cleaned, all melt pressure sensor from the barrel should be removed to avoid damage. When removing the sensor, the melt may flow into the mounting holes and hardened, if these residual melt is not removed when the installation again melt pressure transducer may cause damage to the top. Cleaning Kit to make these melt residue removal. However, repeat cleaning process is likely to deepen damage mounting holes for melt pressure sensors caused. If this happens, it should take measures to raise the melt pressure transducer position in the mounting hole. ● Select the appropriate location when the melt pressure transducer mounting position too close to the upper reaches of the production line, the molten material may not be worn on top of the sensor; if the melt pressure sensor is mounted too far back in the position in the high-temperature melting may occur between the pressure sensor and the stroke of the screw body stagnation region of the molten material, where the melt may produce degradation, the pressure signal may be transmitted distortion; if the melt pressure transducer too deep barrel, it is possible during the rotation of the screw touch the top of the high-temperature melt pressure sensor and cause damage. Generally, melt pressure transducer may be located on the screen in front of the barrel, before and after the melt pump or mold. ● Carefully clean before using a wire brush or special compound extruder barrel cleaning, should all melt pressure sensors are removed. Because the two cleaning methods are likely to cause vibration film melt pressure sensor damage. When the barrel is heated, it should be removed melt pressure sensor and use does not produce wear a soft cloth to wipe the top, while the holes melt pressure sensors also require drills and bushings with clean clean. ● Keep dry despite melt pressure transducer circuit design can withstand harsh extrusion processing environment, but most of the high-temperature melt pressure sensor can not be absolutely waterproof, in a wet environment is not conducive to the normal operation. Therefore, the need to ensure that water cooling extruder barrel in the water will not leak, will adversely impact on the sensor. If the sensors have to be exposed to water or moisture in the environment, it is necessary to select a special high-temperature melt pressure sensor has a very strong water repellency. ● Avoid low interference in the extrusion process, in terms of raw materials for plastics, from solid to molten state should have plenty of time to soak. If the extruder before the start of production has not yet reached operating temperature, the high-temperature melt pressure sensor and the extruder will be subject to a certain degree of damage. In addition, if the melt pressure sensor from the cold extruder were removed, the material may be adhered to the top of the melt pressure sensor vibration caused by damage to the membrane.