Ton bags are common transportation packaging in sea, rail and road transportation. With the deepening of reform and opening up and the development of the national economy, the demand for flexible large bags continues to increase. At the same time, in recent years, the inspection tasks for ton bags have also increased year by year, especially the arbitration inspection on the quality of ton bags. The quality inspection agency is required to provide scientific and reliable data for the arbitration agency, which puts forward higher requirements for the inspection work. .
1. The technical requirements for ton bags stipulate that the limit tolerance of ton bag sizes below 1000mm is ±20mm, and above 1000mm is ±30mm. However, the size of some big bags is just 1000mm, and there should be tolerance requirements for this size. It is recommended that when the size of the big bag is ≤1000mm, the limit tolerance of the big bag is ±20mm.
2. The ton bag manufacturer stipulates the physical properties of the ton bag base fabric, among which the tensile strength of the cloth at the inlet and outlet positions is required to be ≥828N5cm. Because the stress on the cloth in this part is relatively small, in the long-term inspection work, it was found that the manufacturer did not use high-strength cloth for this part, and no influence was found in the actual use process, but if you press If the test is performed according to the current standard, the test result is unqualified. We suggest that the tensile strength index of the base fabric of this part should be appropriately reduced.
3. About the test method of ton bag.
1. Regarding the measurement of the diameter of a round ton bag, a method of measuring the folded diameter of the bag and then converting it into a diameter is stipulated. We know that the raw material of some round ton bags is cylindrical cloth. In order to calculate the diameter of the finished bag, it is more convenient to measure the folding diameter during the production process. The raw materials for some round ton bags are not cylindrical fabrics, but flat fabrics. During the production and processing, the circumference needs to be converted into diameters. During the sewing process, errors in the diameter of the finished bags may be caused.
On the other hand, in our actual inspection work, when measuring the folding diameter of the finished bag, because the big bag has been processed, it is difficult to spread the big bag flat when measuring the sample bag. The two ends of the bag (bottom and cover) Part of the Z-large size is the diameter of the bag, while the middle bag body is larger in size, and the size at both ends becomes smaller. In the implementation of specific measurements, certain measurement errors will always be caused. Therefore, from the detection point of view, it is recommended that the method of measuring the diameter of the ton bag sample should not be converted, and the method of directly measuring the diameter of the bottom and lid of the bag should be used, which is simple and accurate.
2. Regarding the measurement of the folding diameter, the standard stipulates the folding diameter of "measure two different parts". Changzhou Ton Bag Editor believes that the specific parts of the measurement should be specified here, so that it can be operability, and the measurement method is more unified and standardized.
3. Because the measuring tool of the ton bag size is set as a steel tape measure, the measuring accuracy should be specified to be accurate to 1mm.
4. Regarding the standard environment for state adjustment and testing of plastic specimens, the tensile strength and elongation test environmental conditions stipulated by the standard are 20±2°C, rh65%±5%. At present, international and domestic testing of plastic packaging materials, unless otherwise specified, should generally be tested under the conditions of 23±1°C (or ±2°C), rh50%±2% (or ±5%). The same applies to the testing of slings, slings and other parts of the sample.
5. For the sampling method of the connection part of the ton bag, the size of the sample is specified in the standard, but the sampling method is not clearly specified. In the test work, the connection part (main body connection, bottom connection, etc.) and the tensile stress part of the sample (width 110mm) should be cut by electric heating to prevent the fiber and suture of the sample from being damaged.