When we choose the sling, we need to consider the following principles:
1. Selection of sling specifications and types: In general, we suggest that the load, size, shape, weight and hoisting scheme of the object to be lifted should be considered in the selection of specifications, and then the specifications of the sling should be designed according to calculation of relevant sling design and mechanical principle. Whether accessories or soft lifting lugs are needed, the end of the sling must be carefully considered to match the auxiliary accessories and lifting equipment.
2. Limited use Angle of sling: When flat sling with soft lug is used, the minimum length of lug used shall not be less than 3.5 times the maximum thickness of the hook in contact with the lug, and the included Angle of the lug movement shall not exceed 20°. When connecting a sling with a lifting appliance with a soft lug, the sling must be in constant contact with the lifting appliance unless the axial width of the sling does not exceed 75mm and the bending radius of the lifting appliance must be at least 0.75 times the axial width of the sling. Example: the sling has a radius of at least 0.75 times the axial width of the sling on the cargo hook. The fabric width may be affected by the radius of the inner part of the cargo hook, and the effect of the curvature of the cargo hook may prevent the effect of strength on the balance of the width of the fabric. Overloading of slings is strictly prohibited and the correct mode coefficient must be used. Part of the mode of ultimate working force may be given on the label. Multiple combination slings must not exceed the maximum Angle in the vertical direction.
3. Follow good hoisting experience. Plan hoisting and light operation plan before starting hoisting.
4. When hoisting, correctly use the connection mode of the sling and the sling should be correctly placed and connected with the load in a safe manner. The sling must be placed on the load so that the load can balance the width of the sling; Never tie or twist the sling stitch should not be placed on the hook or lifting equipment and should always be placed on the upright part of the sling to prevent damage to the label by staying away from the load, hook and locking Angle.
5. Precautions for the use of multiple combination slings: The evaluation of the ultimate working force of multiple combination slings depends on the symmetry of the combined slings’ load, that is, when hoisted, the branches of the slings are evenly distributed according to the design with the same vertical Angle. 3 Combined slings, if the branches cannot be uniformly stressed by the design, the maximum strength on a branch will be the sum of the maximum bearing capacity of the branches adjacent to the design Angle. The same result will be included in the 4 combined slings if the load is not rigid. Note: for rigid loads, most of the gravity may be carried by 3, or even 2, with the remaining balanced rotating rings that only protect the load
6. When hoisting, the sling protection shall be kept away from sharp edges, friction and wear, whether away from load or lifting appliance, and the proper part of the sling shall be strengthened and protected from damage of sharp edges and wear, and the necessary additional reinforcement of protection is necessary.
7, ensure lifting, load balance in the lifting process, must use the sling in a safe way, can not let the load tilt or slip from the sling; The sling must be arranged directly above the center of gravity of the load and the lifting point, so that the load is balanced and stable. If the center of gravity of the load is not under the lifting point, the sling in motion may cross the key, leading to danger.
Post time: Aug-05-2020