Application of the hottest paper moisture meter in

Application of paper moisture meter in the packaging industry

I. significance of paper moisture content test

paper packaging materials play an important role in packaging materials, accounting for more than 40% of the whole packaging materials. From the perspective of development trend, it is an important packaging material now and in the future, and plays an irreplaceable role. However, paper packaging also has many shortcomings, especially its strong water absorption, and its performance changes greatly with the increase of water content, which will even affect the use performance and safety, especially in high temperature environment. Taking corrugated boxes as an example, the research on wiping all parts of the equipment and the amount of molds with clean gauze shows that the mechanical properties of paper packaging decrease significantly with the increase of moisture content. Therefore, it is of great significance to master the moisture content of paper anytime and anywhere in the process of producing and using paper. However, the traditional gravimetric method not only has low accuracy, but also takes a long time to test the moisture content of paper, so it is difficult to effectively master the performance of paper. Based on this, Jinan Drake instrument food and beverage packaging will be the largest major utilization field of biodegradable plastics. Many accessories originally made of steel materials (such as aluminum wheel hubs) have been popularized in automobiles. The company uses its own advantages to cooperate with colleges and universities, introduces foreign advanced high-frequency technology, and introduces high-performance digital moisture measuring instruments suitable for the packaging industry. Since its launch, it has been favored by many packaging enterprises that produce and use paper, cardboard, corrugated boxes and so on. In order to better understand the high-frequency paper moisture meter, the author gives a more detailed introduction from principle to use combined with work practice

II. Test principle

a natural frequency is set in the high cycle paper moisture meter. The moisture of the tested object is different, and the frequency transmitted into the machine through the sensor is different. The difference between the two frequencies after comparison is converted into current through the frequency current converter, and into digital display through the analog-to-digital converter. As shown in the figure:

III. performance introduction

wide measurable range: 0% - 40%; Wide application environment: -5 ℃ - +60 ℃

IV. usage

1. First, select the gear according to the different paper tested. (Grade 8: carton and corrugated board; grade 7: pulp board; grade 5: paper below 50g; grade 4: corrugated paper, writing paper, kraft paper, carton board; grade 2: paper, whiteboard, coated board; grade 0: copper board, copy paper, fax paper) due to different paper structures and different dielectric coefficients, the above gears are the recommended gears. If there is any error, it can be compared and verified. For example, measure a paper with a known moisture of 8%, When the rotary dial is in gear 6, the number is displayed as 8.0. In the future, when measuring the same kind of paper, turn the dial to gear 6

2. Hand held instrument (the probe should not contact with the measured object), turn on the switch (turn the switch to on) and the digital display is within ± 0.5. If not, 3. The model of the equipment can be divided into digital display and microcomputer control. Within its range, slowly adjust the zero knob to make the digital display within ± 0.5

3. Measurement: press the probe against the paper surface (the paper thickness should be more than LCM), and the round head of the sensor contacts the paper surface in a straight line, that is, the instrument remains parallel to the paper, turn on the switch (turn the switch to on), and after the number is stable, the displayed number is the moisture value of the measured object. The whole test process only takes a few seconds

4. Precautions in the test process: due to the strong penetrability of high-frequency waves, there should be no iron plates or magnets at the bottom and around the tested object during measurement

to sum up, due to its wide measurement range, high accuracy, small volume and light weight, the high frequency paper moisture meter can be carried on site for rapid detection, so the instrument will become the most powerful assistant for packaging workers to know the moisture content of paper at any time