An explanation of the lifting of the steel grabber and the correction of the steel column
1. Lift the steel grabber.
According to the shape, end face, length, crane performance and other specific conditions of the steel column, determine the lifting direction and quantity of the steel column equipment. The common methods of steel column lifting include rotation method, delivery method, and sliding method. For heavy steel columns, double-machine lifting can be selected.
Rotation method) The steel column is transported to the site, and the crane is lifted, suspended and rotated to make the column rotate around the column foot, thereby lifting the steel column.
After 1~2 cranes are used to lift the column dead, the sliding method is used to slide the steel column foot into place. In order to reduce the friction between the column foot and the ground, a taxiway can be laid.
(Delivery method) Two or more planes are lifted, and one of them is the auxiliary plane. In order to reduce the friction between the steel column foot and the ground, the auxiliary machine hoisting point is selected under the steel column and hooked with the main engine; with the lifting of the steel grabber main machine, the auxiliary machine hoisting point walks or rotates, and the steel column foot is thrown away. To the column foundation, throw the steel column foot onto the column foundation and remove it.
Ordinary steel columns should be suspended at one point, the earlobes should be placed on the top of the column, and the column body should be vertical, which is convenient for alignment; For steel columns, two or more points can be selected.
If the hoisting of the steel grabber is to bind the steel wire rope directly to the steel column itself, it is necessary to pay attention to the four corners of the steel column to make the included angle to prevent the steel wire rope from being cut off; at the binding place, in order to avoid the partial kneading damage of the steel column, a reinforcing plate can be added. Add support rods.
Before lifting, tidy up the base plate first. The operator lifts the steel column onto the foundation, stands in a good position, stabilizes the column foot and places it on the base plate. When the column drops to the base plate, stop the hook drop. , Use a crowbar to hoist the column above the base. When checking the axis of the column foot and the base plate, stop the hook drop, use a crowbar to pry the column to make it align with the center line of the column foundation, and check the axis of the column foot and the foundation plate. After alignment, spot weld positioning. If the column foot of the connecting plate has been welded, after the crane aligns the steel column connecting plate with the anchor bolts and the connecting plate, the steel column falls to the surface of the foundation plate, and the steel column is fixed with nuts immediately.
The crane of the same type should be selected as far as possible for double or multi-machine lifting, and the load should be distributed to the lifting points according to the crane's ability. The load of each crane should not exceed 80% of its corresponding lifting capacity. To cooperate with each other to prevent the crane from losing weight and overloading the other crane.
2. The steel column correction of the steel grabber.
A piece of steel structure, such as columns, beams, roof trusses, skylight brackets, brackets, etc., should be corrected immediately. Moreover, it must be fixed. Do not correct it after a large piece of equipment. This cannot be corrected, and it will affect the correct orientation of the entire structure, which is not allowed.
Elevation of the bottom plate of the steel machine column: According to the actual length of the steel column, the flatness of the column bottom, and the distance between the top of the column and the bottom of the column, ensure the elevation value of the top of the column, and then determine the adjustment value of the base elevation.
Longitudinal cross: When the bottom of the steel column is processed, punch the steel on one side of the bottom edge of the column, punch out four mutually perpendicular surfaces, one point on each surface, use three points to the cross line of the base surface, and strive to reach the point line The coincidence, if there is an error, you can borrow the line.
The verticality of the steel grabbing machine column: the two theodolites find the column at a vertical angle of 90°, and use the cable wind rope to correct it. The nut under the bottom plate should be adjusted continuously until it meets the requirements, and the double nut above the bottom plate should be screwed on; loosen the cable to make the steel column in a normal state, and then check with the theodolite. If there is a small error, adjust the lower nut and meet the requirements, Tighten the nut; after the correction is completed, the nut can be welded to the threaded rod.