Design of Test Plan for Composite Strength of Film-covered Products (Part Two)

3.3 Test Plan

According to the relevant provisions of the referenced national standards, combined with the performance and characteristics of the selected test equipment, after repeated testing, modification and improvement, the following test scheme was designed to test the composite strength of the covered products.

3.3.1 Provision of Specimen Size

In order to ensure that the effective peeling length is 120 mm, according to the relevant provisions of the reference standards and the actual conditions of the test equipment, the width of the test specimen in the test is specified as 15mm in width and at least 2O5mm in length (the length of the sample may be lengthened to facilitate the experimental operation). .

3.3.2 Preparation and Processing of Specimens

Both ends of the sample in the width direction are removed by 50 mm, and 6 vertical and horizontal samples are uniformly cut along the width of the sample. The direction of the composite film is vertical. The paper base and plastic film were stripped approximately 50 mm along the length of the specimen, requiring no significant damage to the stripped portion. In this way, it is ensured that the sample can meet the effective peel length of 120 mm during peeling (plus 25 mm of initial peeling without data statistics and IO mm before peeling, total peel length or composite length of 155 mm). Claim.

3.3.3 Sample temperature and humidity adjustment and test environment requirements

Treated specimens should be placed in an environment with a temperature of 23 degrees Celsius ± 2 degrees Celsius and a relative humidity of 45% to 55% for more than 4 hours and tested in the above environment as much as possible.

3.3.4 Test Speed ​​Provisions

With reference to the relevant standards, and according to the performance of the test equipment, the test speed is specified as (300 ± 50) mm/min.

3.3.5 Test Procedure

(1) Equipment preparation

The device is placed on a stable work surface, and adjusted to the level; connected to power, the device automatically enters the prompt screen, press the "monitor" button to enter the main display, and then press the "monitor" button to select the experimental project.

(2) Selection of experimental items and setting of parameters

The composite strength test of the film products is performed under the “18° peeling” experimental project. According to the test requirements, various parameters are set, such as: length of 12O mm (length of effective test range), width of 15mm, speed of 25Omm /min, etc.

(3) Adjust the chuck position
Connect the "Experiment" button, the sample number is displayed as "l", enter the standby state. Press the "Drop", "Microlift", and "Stop" keys respectively to adjust the position of the chuck so that the distance between the upper and lower chucks is approximately 90 mm (less than the sample after manual pre-stripping of the paper base and plastic The distance between the two ends of the film is 100 mm to ensure that the sample can be fixed between the two clamps).

(4) Fixed sample
The pre-striped sample paper base end and the plastic film end are respectively fixed between the upper and the lower clamps, and the two are in the same vertical plane, so as to ensure that the pulling force applied during peeling is on the same straight line.

(5) Formal test

Press the “Experiment” button, the device will automatically complete the stripping of the sample. After the stripping is completed, the device will automatically stop. At the same time, the upper chuck will automatically return to the initial position; press the “plus” button to increase the sample number to “2”. The test of the second sample is performed; the test of the third to the sixth sample can also be completed.

(6) Return to the main display for test result display, statistics and printing

Under this test item, choose the sample number, and you can print the test results and the whole tracking curve of each sample (up to 6 samples of the test results can be counted); select the number "7" to print the group statistics Report (given in a list).

4, the significance of the design of the test program

This program is designed for the composite strength test of coated products, with reference to relevant national standards, taking into account the selection of test equipment and some specific problems in the actual operation process. Through repeated tests, revisions, and improvements, the program is realistic, has good operability, and has a certain role in the actual production, testing, and research. The program has the following aspects:

(1) It provides a feasible test method for the testing of the composite strength of film products. At the same time, it provides a quantification of the composite strength (peel strength), which is an important index in the quality inspection and evaluation system of film products. A new idea.

(2) Accurate and reliable data can be obtained through more scientific testing to guide actual production. As mentioned above, the film lamination process is a post-printing surface finishing process. Before the lamination process, printing and other processing processes have already been performed. Therefore, the quality of the laminating products is not only influenced by various parameters of the laminating process, but also Also affected by the pre-order process. With this test scheme, the parameters of the lamination process and the pre-process can be regularly changed, and then the composite strength of the product can be tested to obtain a set of test data. After scientific analysis, the Laws, used to guide actual production.

(3) Construction of relevant national standards. In the existing national standards, the quality inspection method for film-covered products only requires visual inspection based on experience, and in the actual operation process, only the “see”, “fold”, “defective” and other empirical methods are used for quality evaluation. This method is difficult to achieve the consistency of the test standards, and it is also lack of persuasion. Through the design and practical application of the test plan, it can play a role of “discussing the jade” and provide a new idea for relevant personnel. At the same time, it also does some basic work for the construction of related standards.


Source: HC Business Network