Roughness tester

Principle
Roughness (Sheffield Method): This test is an indirect measure of paper smoothness or roughness. It is a measurement of air flow between the specimen (backed by flat glass on the bottom side) and two pressurized, concentric annular lands that are impressed in to the sample from top.
How to use
Turn on the power switch of the tester
Check and enter the measuring date on the display (of the operation panel)
Warm up the control devices of the tester for 15 minutes(in normal atmosphere) or 45 minutes(in cold atmosphere)
See table 1 to select a suitable backing. using air or methyl alcohol, clean the backing surface(the lower measuring head for air permeability), make sure that the surface is free from dirt, dust, damage, the place the backing in the ID (inner diameter)of lifting cylinder(off white).
Remove the protection cover of the roughness or permeability measuring head, clean with air or methyl alcohol the portion which comes in contact with the specimen. Be sure that the portion is free from dirt, dust, damage, then insert the head into the notch in the head holder, with the head upper flange being horizontal.
Be sure that the compressed air pressure at the sources is 4.5 kg/sq cm or more, and open the sluice valve
Press the manual start key to check the clamp for smooth climbing under the clamping initial pressure.
After calibrating check the data of the measuring head pressure and clamping pressure, check the data on the display to judge whether it is necessary to change the entered data such as

measuring conditions
Insert the specimen under the measuring head with the surface to be tested facing upwards, so that the surface may receive the light of photoelectric switch(Infrared LED)
one second after, the specimen is automatically clamped and the measurement begin
After the time setting, the result of the measurement is display and the clamping is released.
For continuous measurement , move the measuring spot of the specimen immediately.
If the specimen detected continuously by the photoelectric switch, the specimen is clamped again automatically 3 second after the end of the previous measurement, to start the second measurement.
For measurement of compressibility, the roughness is measured with the lower clamping pressure, then with the high pressure
If there is any abnormal state during the measurement, delete by pressing the del key and specifying the measurement No. for the message “quit test”
If the measurement is continued for a long span time, dust or paper powder would stick to the measurement head or backing surface. clean it. Wait 2 to 3 second before restarting the measurement
Check the measurement on the display, if OK, press ‘YES” key to perform statistic processing by computer(average, maximum, minimum, standard deviation, variation coefficient) to show the result on the display
If the specimen detected continuously by the photoelectric switch, the specimen is clamped again automatically 3 second after the end of the previous measurement, to start the second measurement.

ROUGHNESS TESTER
Construction

Operation panel
Main power switch
Display
Printer
Printer power switch
Level adjusting pad
Head holder
Measuring head
Backing
Backing holder
Photoelectric switch