(Continued from the previous period)
However, due to the limitation of testing methods, the number of corrugated sheets that are stripped during actual testing is at most n-1, so there are two views and approaches for the value of the number of corrugated sheets, one is to take all the samples contained on the sample ( (Intact) Number of turns; the other is to take only the actual number of peeled turns of the sample, ie at most n-1. According to this recognition, formula (2) becomes P=F/L·(n-1) or in formula (2), n is the actual stripping parameter. Therefore, the same type of bond strength value will vary greatly due to the different values ​​of the number of turns of the tester. This is a problem that needs to be unified in practice.
4. The revised GB 6548-98 stipulates that the bond strength result is expressed as N/m, the calculation formula is P=F/L, (3), where the length of the long side of the L-specimen in the formula, m; is obtained from (3) The value of the adhesive strength substantially means the maximum separation force required for stripping a unit length of corrugated cardboard when the width, that is, the twisting length, is constant (25 mm). The concept of bond strength is more similar to (1), N/m2, and there is a mathematical conversion relationship between them: 1N/m2 = 0.024 N/m.
The new standard expresses new regulations for the results of the adhesive strength of corrugated cardboard and clarifies some of the misconceptions in the old standard. However, since the current revision of the corrugated box product standard is not synchronized with the method standard, the change in the bond strength result in the new standard causes a vacuum in the evaluation criteria for the bonding quality of the corrugated box. At present, there are two main product standards, and the standard value of the bond strength in the “Detailed Rules†is not less than 58800N/m2, but not less than 588N/m•inch in SN/T0262-93. In addition, in the inspection practice, if the same sample is calculated under the same conditions using equations (1) and (2), respectively, and judged according to the above two criteria, two completely different conclusions may be obtained. For type B samples, the maximum peel force (=12 turns) is F=120N. Calculate P=60000N2/m2 according to formula (1); the sample is judged to be acceptable and calculated according to formula (2). P=400 N/m·楞; the sample was judged as unqualified. In view of this, it is imperative that the unity of the corrugated box product standard is revised and the standards are united. Third, the conclusion GB6548-98 is equivalent to the Japanese standard JZS0402-88 "Corrugated board adhesive test method", this method has also been adopted by many international countries. To make this standard practically implemented in China, it requires the joint efforts of people in the industry and related departments.
1. The relevant departments should speed up the revision of the "Detailed Rules" and GB6544-86 "Corrugated Cardboard", GB5034-85, SN/T0262-93 and other product standards, so that the standard value, calculation formula and results of the corrugated board adhesive strength As soon as possible unified to GB6548-98 up.
2. Unified detection methods, which completely eliminate the non-standard tools, ie double-sided comb stripping racks, in the testing practice, using standard unilateral rigid pins and support frames. (such as WZL-3 type produced by Sichuan Changjiang Paper Instrument Factory)
3. Before the relevant standards have been revised, regarding the value of the number of corrugation in formula (2), the author believes that the actual number of corrugated sheets that were not stripped at the end of the test is an indeterminate value, ie, it is irregular. Therefore, in (2), the number of flutes (n-1) is not appropriate. If calculated according to the actual stripping factor, many human factors will be added, resulting in inconsistent data processing and even misjudged. In addition, from the meaning of F, F refers to the maximum separation force required for the sample to be completely separated. During the test, the final display force value of the instrument is the maximum separation force. At this time, even if there are still corrugated samples in the sample, Connected to the paper or core paper, the force value will not increase if the sample is continuously pressed. Therefore, from the viewpoint of the correct understanding of the standard and the harmonization of methods, the first viewpoint and practice are taken for the value of the sample corrugation in (2), that is, the number of all (complete) turns contained on the sample is correct. .
4. In the current situation, inspectors should be familiar with and master the relevant national standards and industry standards. In particular, they should deeply understand and understand GB6548-98. There should be a good understanding of the differences between standards and test methods. Eliminate the influence of objective factors and human factors on the adhesive strength of corrugated cardboard. This point is particularly important for quality inspection agencies that hold product quality judgments. (Finish)
However, due to the limitation of testing methods, the number of corrugated sheets that are stripped during actual testing is at most n-1, so there are two views and approaches for the value of the number of corrugated sheets, one is to take all the samples contained on the sample ( (Intact) Number of turns; the other is to take only the actual number of peeled turns of the sample, ie at most n-1. According to this recognition, formula (2) becomes P=F/L·(n-1) or in formula (2), n is the actual stripping parameter. Therefore, the same type of bond strength value will vary greatly due to the different values ​​of the number of turns of the tester. This is a problem that needs to be unified in practice.
4. The revised GB 6548-98 stipulates that the bond strength result is expressed as N/m, the calculation formula is P=F/L, (3), where the length of the long side of the L-specimen in the formula, m; is obtained from (3) The value of the adhesive strength substantially means the maximum separation force required for stripping a unit length of corrugated cardboard when the width, that is, the twisting length, is constant (25 mm). The concept of bond strength is more similar to (1), N/m2, and there is a mathematical conversion relationship between them: 1N/m2 = 0.024 N/m.
The new standard expresses new regulations for the results of the adhesive strength of corrugated cardboard and clarifies some of the misconceptions in the old standard. However, since the current revision of the corrugated box product standard is not synchronized with the method standard, the change in the bond strength result in the new standard causes a vacuum in the evaluation criteria for the bonding quality of the corrugated box. At present, there are two main product standards, and the standard value of the bond strength in the “Detailed Rules†is not less than 58800N/m2, but not less than 588N/m•inch in SN/T0262-93. In addition, in the inspection practice, if the same sample is calculated under the same conditions using equations (1) and (2), respectively, and judged according to the above two criteria, two completely different conclusions may be obtained. For type B samples, the maximum peel force (=12 turns) is F=120N. Calculate P=60000N2/m2 according to formula (1); the sample is judged to be acceptable and calculated according to formula (2). P=400 N/m·楞; the sample was judged as unqualified. In view of this, it is imperative that the unity of the corrugated box product standard is revised and the standards are united. Third, the conclusion GB6548-98 is equivalent to the Japanese standard JZS0402-88 "Corrugated board adhesive test method", this method has also been adopted by many international countries. To make this standard practically implemented in China, it requires the joint efforts of people in the industry and related departments.
1. The relevant departments should speed up the revision of the "Detailed Rules" and GB6544-86 "Corrugated Cardboard", GB5034-85, SN/T0262-93 and other product standards, so that the standard value, calculation formula and results of the corrugated board adhesive strength As soon as possible unified to GB6548-98 up.
2. Unified detection methods, which completely eliminate the non-standard tools, ie double-sided comb stripping racks, in the testing practice, using standard unilateral rigid pins and support frames. (such as WZL-3 type produced by Sichuan Changjiang Paper Instrument Factory)
3. Before the relevant standards have been revised, regarding the value of the number of corrugation in formula (2), the author believes that the actual number of corrugated sheets that were not stripped at the end of the test is an indeterminate value, ie, it is irregular. Therefore, in (2), the number of flutes (n-1) is not appropriate. If calculated according to the actual stripping factor, many human factors will be added, resulting in inconsistent data processing and even misjudged. In addition, from the meaning of F, F refers to the maximum separation force required for the sample to be completely separated. During the test, the final display force value of the instrument is the maximum separation force. At this time, even if there are still corrugated samples in the sample, Connected to the paper or core paper, the force value will not increase if the sample is continuously pressed. Therefore, from the viewpoint of the correct understanding of the standard and the harmonization of methods, the first viewpoint and practice are taken for the value of the sample corrugation in (2), that is, the number of all (complete) turns contained on the sample is correct. .
4. In the current situation, inspectors should be familiar with and master the relevant national standards and industry standards. In particular, they should deeply understand and understand GB6548-98. There should be a good understanding of the differences between standards and test methods. Eliminate the influence of objective factors and human factors on the adhesive strength of corrugated cardboard. This point is particularly important for quality inspection agencies that hold product quality judgments. (Finish)