Determination of inflation coefficient of bronzing plate

Depending on the materials used, the bronzing plate is divided into a copper plate and a zinc plate. However, these two materials will expand when heated. Therefore, in order to ensure the accuracy of the hot stamping, the sizing rate of the plate should be taken into consideration when making the bronzing plate. , and appropriate shrinkage processing. To this end, the author has done a special experiment (bronzing version of the corrosion of copper plate, using a semi-automatic hot stamping machine, heating temperature is 100 ~ 150 °C), the experimental steps are as follows.

1. Make two hot stamping copper plates A and B, in which version A is 21.07cm long and B plate is 18.27cm long.

2. Two copper plates are installed at the same time and hot stamping is performed. The lengths of the electrographic aluminum texts on the paper after stamping are measured to be 21.1 cm (version A) and 18.3 cm (version B), respectively.

3. Calculate the expansion coefficient of the copper plate

A: 21.1 ÷ 21.07 ≈ 1.004

B: 18.3÷18.27≈1.0016

Average: (1.0014+1.0016)÷2=1.0015

That is, the coefficient of expansion of the copper plate under this stamping condition is about 1.0015. On this basis, the plate was again plated. The length of this copper plate was 21.038cm (21.07÷1.0015=21.038). The length of the electrographed aluminum plate on the paper after stamping was about 21.07, and the error was less than 0.01cm. Significantly increased. The same method was used to test the zinc plate and the zinc plate had a coefficient of expansion of about 1.0038.
The above method is only a little experience in practical work and is willing to communicate and share with peers.

Source: Hangzhou Haitian Special Printing Co., Ltd.