The correct use of sling (lifting belt, wire rope sling) lifting large workpiece
With the rapid development of the national economy, heavy lifting work with survivors in all fields of economic construction are more frequent and widespread. In view of this situation, some lifting equipment and hanging rigging manufacturing enterprises to seize the market and improve the lifting equipment and lifting rigging performance and technology content, have been developed and the development of different specifications of new hoisting equipment and rigging, which part of the product has formed series of standards and.
Lifting operation commonly used sling and rigging and end fittings, according to the habit of industry, we put for hoisting and lifting operation of rigid fetching device called for a lifting tool, such as: hook, grab, a clamp, a sucker, a special spreader; the binding workpiece flexible tool called for rigging, such as: steel wire rope, chain, Xingsheng synthetic fibre sling; the end parts commonly used have rings, shackle, wire card.
Heavy weights fall, is a major attack damage, including heavy damage caused by the two damage. Caused by the fall of a variety of reasons in a sling used improperly, weight bundle and not in prison, hooking and unhooking, sudden power failure of the sucker, hanging rigging standard application, for improving the safety and reliability of the equipment itself and in the process of operation, improve work efficiency will play great role. At the same time, the process and characteristics of the lifting operation, it has determined that the lifting operation is a kind of special operation with higher degree of danger. Due to the operating personnel in the use of these hanging rigging check of is not standard and use of improper, often lead to accidents, this case also may be too numerous. Therefore said: lifting sling is small, but it is very important, we should not be regard as unimportant.
Of crane accident statistics and analysis show that because of the workpiece hanging location choice is not correct, rigging, improper use and play heavy accidents occupy a considerable proportion, especially some large parts of lifting, due to our cable staff hook technology quality is low and the responsibility heart is not strong, often lead to accidents, and caused significant economic losses. If a unit linked to the staff in using 2 root diameter of 43.5mm steel wire rope double pocket hanging 3 folds put a total of about 72 tons of steel, due to the diameter of the rope and choose small overload hoisting and edges without protective padding, when the plate has risen to about 2.5 meters high, steel wire rope in corners of the fracture, leading to the plate falling. Again, a unit linked to the personnel from flat car hoisting and unloading a weight of 45 tons of workpiece, due to illegal operations (the workpiece itself set four rings, hanging only with the three), after the lifting of the workpiece is inclined to fall, the impact will be wire breakage, resulting in the falling of workpiece. Therefore, in the use and management of the rigging, not negligence and let down. So how to safely use the sling?
First, determine the operating program
Lifting operation is a strong technical and dangerous, the need for more people to cooperate with each other, coordination, unified command of the special types of work. So the operating personnel must be trained and certified. Before work must also for field operation environment, weight lifting the weight and the gravity center of the line, the workpiece, rigging, with play equipment whether to meet the needs of, calculation and analysis, the correct formulation of play scheme.
Two, the correct use of sling:
1、 the user should be familiar with all kinds of rigging and end fitting itself performance, precautions, scrapped.
2、 the selection of slings should be hanging the shape characteristics of the workpiece and the specific requirements of fit, in does not have the conditions of use cannot deal with.
3、before the operation, with sling and accessories for examination, confirm intact, can be used.
4、 before the suspension, should be the right choice of cable; before ascension, should confirm whether firmly tied.
More than the rated lifting weight 5, sling and accessories, sling shall not exceed the corresponding hanging under the condition of maximum working load.
To prevent damage to the rigging and accessories, 6 operations, should be added at the edges in the corner door when necessary.
7、 rigging in the use of internal insist on regular inspections, conditional, of large tonnage and important product sling and end fittings should be testing.
Three, grasp the essentials of large pieces of lifting
For large workpiece lifting or assembly in place, due to the large tonnage parts, complicated, expensive, many people cooperate, to further improve the operation difficulty and risk coefficient. Therefore, when large workpiece slings should be grasp and the following Essentials:
1、before the operation to observe the shape of the workpiece, grasp the center of gravity of the workpiece, and confirm the weight of the workpiece according to the drawings.
2、 the correct choice of ropes, shackles, hooks and other rigging. Selection of wire rope, single rope bearing force, according to S (Newton) =100 - D2 calculation formula. Where: D is the diameter of the wire rope, the unit is mm.
3、 of the workpiece itself is designed for hoisting and design of the ring, or a hanging ear, before the operation should check carefully, and should be in all the rings on the Caucasus.
4、the workpiece itself does not ring, should be the right choice of cable point. And the hook head of the crane is aligned to the center position of the workpiece.
5、 pay attention to the angle between the rope should generally be less than 90 degrees.
6、 corners, rope passes through the angle of protection must be added.
7、 lifting before trial lifting process, confirm and then continue to the next step of work.