Automatic hot stamping accuracy and test method of

The author raises doubts about the accuracy and test method of automatic hot stamping

in view of the contents of 4.9 and 5.8.2 of the technical conditions of the flatting hot stamping machine in the fourth issue of the standardization of printing machinery in 1998, and expounds the following opinions for the consideration and approval of the relevant experts of the Standardization Committee. Excerpts from the original text are as follows:

I. restate the contents of 4.9 and 5.8.2 of the technical conditions of the flat press and hot stamping machine

4.9 the error of repeated hot stamping shall not be greater than 0.20mm

5.8.2 repeat the test of hot stamping error

take 10 consecutive samples, measure the three hot stamping widths on the hot stamping machine sheet with a vernier caliper, take the average value, then carry out the second hot stamping, and then measure the overlapping and printing widths on each sheet respectively

second, analysis

first of all, the reference to the precision of repeated hot stamping, that is, hot stamping multiple times at the same position on a piece of paper, which is inconsistent with the actual hot stamping of official prints, which can be said to be completely impossible; Secondly, the above method is used to check the accuracy of the machine. In many cases, the basic result is the superposition of multiple machine errors, This can be further discussed in the following discussion, "said Zheng Daqing, senior vice president of BASF Greater China: "BASF is eager to contribute its own efforts to the soil protection in Xinjiang and the whole country. In addition, the repeated hot stamping error test in 5.8.2 of the standard is unreasonable, and it is also explained below.

the full text of the analysis is as follows:

set conditions: 1. Eliminate printing errors.

2. Eliminate paper errors.

here is the size of one piece and one direction of the hot stamping method The irrationality of the original standard

the following is the analysis result of each sample sheet:

first sheet: the first sheet is hot stamped at the position of line 0; The second hot stamping moved up 0.2mm, which belongs to the qualified product, and the printed product is also qualified

second sheet: the first hot stamping is at the position of line 0, and the second hot stamping is moved down by 0.2mm; It belongs to the qualified products, and the printed products are also qualified

third sheet: the first hot stamping moved up by 0.2mm; The second hot stamping down 0.2mm belongs to unqualified products, but the printed products are qualified

fourth sheet: the first hot stamping moved down 0.2mm; The second hot stamping was moved up by 0.2mm, which was unqualified in the inspection, but the printed product was qualified

fifth sheet: the first hot stamping was moved up by 0.2mm; The second hot stamping was moved down by 0.4mm, which was qualified in the inspection, but the printing was unqualified

sixth sheet: the first hot stamping moved down 0.2mm; The second hot stamping moved down 0.4mm, which belongs to the inspection product, but the printing product is unqualified

to sum up, the repeated hot stamping accuracy and test method in the original standard are reasonable in the first and second sheets, and the third and fourth sheets mistakenly regard qualified products as waste products. Obviously, it superimposes the two errors of the machine, rather than the primary accuracy of the machine. In the fifth and sixth sheets, the waste products are judged as qualified products, which also superimposes the two errors of the machine, which are the two errors of the machine

III. conclusion

the repeated hot stamping error in the original standard should be changed into hot stamping error, and its inspection method should also change the two hot stamping of the same paper into one hot stamping. For the hot stamping error test, 10 pieces should be randomly selected, and the distance between the front gauge edge and the front edge of the hot stamping pattern should be measured. The size Y1, Y2... Y10 is very small. Take the average value y of Y as the ideal 0 line. Compare the measured data with y, if it exceeds the specified value, it is unqualified, and the error is selected symmetrically with y, i.e. ± 0.2mm

note: please refer to the original and translation of the product acceptance conditions of sp104er and sp102bma of Swiss Bobst company