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Job report Static image taken with a 10x zoom lens. Answer the following questions in the report
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Job report
Static image taken with a 10x zoom lens. Answer the following questions in the report 1. Describe the anisotropy property of paper. 2. The importance of determining the direction of the paper machine axis. 3. Make a conclusion based on the observed results. Control questions: 1. How can the direction of the machine axis be determined? 2. How do you understand "anisotropy"? 3. Why the strength of the paper is higher along the axis of the machine. 4. Which direction is called the axis of the car? 2-LABORATORY WORK EVALUATION OF PAPER SMOOTHNESS The purpose of the work: to get acquainted with the methods of determining the smoothness of paper. Tools: YT-ABST automatic smoothness tester Theoretical part Method and sequence of work. Smoothness is one of the main indicators of paper quality. In this work, the YT- ABST automatic smoothness tester devices available in the NamMTI printing laboratory are used for smoothness determination (photo). Students prepare three samples from the provided paper using a template: the smoothness is assessed separately on the right and four sides of the paper. As a conditional indicator of paper smoothness, the rate (duration) of vacuum suction of 10 cm3 of air between the surface of the glass disk and the paper sample was taken (sec) The more uneven the paper, the more time spent will be less. Papers finished with a flat surface and passed through a supercalender have a high level of smoothness. The figure shows the structure of the YT-ABST automatic smoothness tester pneumatic device. The main parts of the device: a paper sample is mounted on the surface of a glass disk 1 on a metal base, a rubber pad 4 is placed on it, and the metal cover 2 on top is screwed and strengthened with a fixing screw 2. 10 - a vacuum is created with the help of a pump. The air tank 9 is connected to the glass disc channel by means of a three-way tap 8. The pressure (at the level of 380 mm) is controlled by the mercury vacuum gauge 11. The time when the pressure drops from 380 to 360 mm is measured in seconds using a stopwatch. These pressure indicators correspond to the passage of 10 ml of air volume. In the report, the arithmetic mean value of the parameters measured on both sides of the paper is given and the level of paper finishing is given. Download 0.83 Mb. Do'stlaringiz bilan baham: |
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