Comparison of chain sling and wire rope sling
Chain Webbing Slings vs. Round Slings slings and steel slings should be used according to actual working conditions. There is no question of who is better than who is better. From a purely safety perspective, chain slings have certain advantages over wire rope slings. The diameter of the bar of the Zhiyuan lifting chain can be 6mm-72mm, and the ultimate working load can reach 1568KN. Under normal circumstances, Zhiyuan chain rigging can achieve a safety factor of 4 times, and can provide products with a safety factor of 6 or 8 times according to the user's working conditions. After long-term use, a good quality chain has an elongation after wear or use. The low-end chain may suddenly break without warning. Strict test data shows that the wear or elongation of Zhiyuan chain rigging exceeds 3%, and the operation is still relatively stable, the frequency of failures is still low, and the wear and elongation can be up to 5%. For more detailed questions, please ask Zhiyuan Chain and Rigging Technical Section 022-58015518. Generally speaking, the elongation of the chain needs to be tested monthly. When the elongation reaches 2.5%, the future service life of the chain should be considered and preparations for replacement should be made.
Most users have compiled a series of hoisting process instructional technical documents according to product categories. They have made more detailed regulations on various hoisting procedures, as shown in the figure, and emphasized the order of various hoisting operations. The correct selection of slings and how to check the contents are obviously insufficient. The author believes that the basic principles and methods of strengthening hoisting operations should be carried out from the following aspects. The selection of suitable slings is the first in China. The sling industry in China has developed rapidly in recent years, but the technical standards are very imperfect. There are only promotion standards and no mandatory standards. Some domestic enterprises produce at will, even lower the safety factor without authorization, OEM, OEM, do routine factory tests that do not comply with the standards, only do wire rope tests, not do tests, or sample finished products. As is common, the actual quality of flexible slings is uneven, and there are certain safety risks.
Therefore, it is obviously necessary to choose a regular flexible belt manufacturer and establish a corresponding account for management. The slings purchased outside must be products produced and inspected by professional manufacturers in accordance with national standards and with certificates of conformity and maintenance and maintenance instructions. Marks such as the rated lifting weight, production number, date of manufacture, and name of the manufacturer that are not easy to wear must be displayed on the product. But these alone are not enough. It is necessary to go to the supplier’s production site for quality supervision and witness whether the production, especially the factory test link, strictly implements the relevant national standards. Mass purchases can be drawn from them for professional measurement in proportion to effectively check whether their nominal load meets the supplier’s qualification certificate.
When necessary, the sheath can even be cut to check whether the number of inner core joints exceeds the standard and whether the material is qualified. When selecting the sling specifications, the size, weight, shape, and hoisting method of the load to be lifted must be considered in the calculation, and the requirements for the ultimate working force must be considered in the calculation. At the same time, the working environment, The type of load must be considered. Choose a sling with sufficient capacity and an appropriate length to meet the usage method. If multiple slings are used for lifting loads at the same time, the same type of sling must be selected; the raw materials of flat slings cannot be affected by the environment or load influences. First, confirm the weight and length of the sling, and use the correct method coefficient. Regardless of whether attachments or soft lifting eyes are needed, careful consideration must be given to matching the end of the sling with auxiliary attachments and lifting equipment.