Coating standard: gb1724-79 determination of fineness of coating

Core tip: this standard is applicable to the determination of coating fineness Using a scraper fineness meter, expressed in microns 1、 General provisions Instruments and equipment: Small paint knife; Scraper fineness meter: (1) The polished plate of the scraper fineness meter is made of tool alloy steel (brand Cr12) There is a long groove (length 155 ± 0.5mm, width 12 ± 0.2mm) on the plate, which is 0-150 μ m (minimum division 5 μ m, groove inclination 1:1000) and 0-100 μ m (minimum division 5 μ m, groove inclination 1:1000) in the length of 150 mm Paint agent, top 10 Chinese wall paint brands Recommended introduction: interior wall paint and exterior wall paint can achieve beautiful, clean and pleasant effects, but the effects in different environments are different, so the color of the paint will be different There are ten brands of Chinese paint, ten brands of global paint, ten brands of Chinese wall paint, and ten brands of Chinese paint, Famous trademark of Chinese paint and coating In private rooms, most of us choose according to our own personality, personal hobbies and living habits The younger generation will choose the interior wall paint with rich colors and bright colors, while the older ones will have some working experience Home of coatings: this standard is applicable to the determination of coating fineness Using a scraper fineness meter, expressed in microns I generally specified instruments and equipment: small adjustment paint knife; scraper fineness meter: (1) the polished plate of scraper fineness meter is made of tools It is made of alloy steel (brand Cr12), on which there is a long groove (length 155 ± 0.5mm, width 12 ± 0.2mm), and 0-150 μ m (minimum division 5 μ m, groove inclination 1:1000), 0-100 μ m (minimum division 5 μ m, groove inclination 1:1500), 0-50 μ M (minimum division 2.5 μ m, groove inclination 1:3000) is engraved in the length of 150 mm to indicate the depth of the groove 。 The allowable straightness difference of the front groove bottom and the back side of the scraper fineness meter is 0.003 mm / full length, the front surface finish shall be △ 10, and the division value error shall be ± 0.001 mm (2) The scraper is made of high-quality tool carbon steel (brand T10A), both edges are polished, 60 ± 0.5mm in length and 42 ± 0.5mm in width, the allowable deviation of blade straightness is 0.002 mm / full length, the surface finish is △ 8, and the grinding finish of blade is △ 10 2 When the fineness of the measurement method is 30 μ m or less, a scraper fineness meter with a measuring range of 50 μ m shall be used; when the fineness is 31-70 μ m, a scraper fineness meter with a measuring range of 100 μ m shall be used; when the fineness is more than 70 μ m, a scraper fineness meter with a measuring range of 150 μ m shall be used The scraper fineness meter must be cleaned and dried carefully with solvent before use, and soft wiping cloth shall be used during scrubbing Mix the sample meeting the viscosity index of the product standard with a small paint mixing knife, and then drop a few drops into the deepest part of the groove of the scraper fineness meter, so as to fill the groove with a little extra Hold the scraper with both hands (as shown in the figure), and place it horizontally on the upper end of the polishing plate (at the edge of the sample), so that the scraper is in vertical contact with the surface of the polishing plate In 3 seconds, pull the scraper from the deep part of the groove to the shallow part, so that the paint sample is filled with the groove and there is no residual paint on the plate After the scraper is pulled, immediately (no more than 5 seconds) make the line of sight form an angle of 15-30 ° with the groove plane, observe the evenly exposed part of particles in the groove with the light, and record the reading (accurate to the minimum graduation value) If individual particles are exposed to other graduation lines, the reading shall not exceed three particles within the range of adjacent graduation lines [see attached figures (1), (2) and (3)] 3 The results and accuracy shall be tested in parallel for three times, and the arithmetic mean of two similar readings shall be taken for the test results The error of two readings shall not be greater than the minimum graduation value of the instrument Note: since the implementation of this standard, the original standard hg2-501-77 is invalid Home of coatings is specialized in coatings, diatom mud, paint coating, coating technology, fire retardant coating news and coating, diatom mud, paint coating, coating technology, fire retardant coating decoration knowledge and decoration renderings,