Key points of tower crane safety supervision?

The safety supervision points of tower crane are very important, and each point is formulated to better ensure the construction efficiency and safety, which is very critical. Zhong Da Consulting will explain the main points of safety supervision for tower cranes.

1) The track foundation of walking tower crane shall meet the following requirements:

① Bearing capacity of foundation: light weight (under 30kN) should be 60 ~100kpa; Medium-sized (lifting weight 3 1 ~ 150kn) should be101~ 200kpa; Heavy (lifting weight 150kN or above) should be above 200kPa;

(2) A gauge tie rod shall be set every 6m, and the allowable deviation of gauge shall be 0 ‰ of the nominal value and shall not exceed 3 mm;

③ In vertical and horizontal directions, the inclination of the rail top surface should not be greater than1‰;

(4) the gap between rail joints shall not be greater than 4mm, and it shall be staggered with the rail joint on the other side by a distance of not less than 1.5 m, and the joint shall be placed on the sleeper, with the height difference between the two sides of the rail top not greater than 2 mm;

⑤ A buffer stop must be set at the end of the track 1m, and its height should not be less than the radius of the walking wheel; The limit switch buffer must be set at a distance of 2m from the track terminal;

⑥ The fishplate connecting bolts shall be fastened, and the backing plate shall be fixed firmly.

2) The concrete foundation of fixed tower crane shall meet the following requirements:

(1) The specific position and size of the foundation shall be determined by calculation according to the provisions of the manufacturer's manual and the actual situation of the bearing capacity of the foundation soil, and the construction can only be started after being reviewed and signed by the construction technical director.

(2) The strength grade of concrete shall not be lower than C35.

③ The allowable deviation of foundation surface flatness is1‰;

(4) The position, elevation, verticality and construction technology of embedded parts meet the requirements of the factory manual.

3) The track foundation of the crane shall be accepted before use.

4) Slope and drainage facilities should be built around the rail foundation and concrete foundation of the crane, and a safe distance should be kept from the foundation pit.

5) The metal structure of the crane, the track and the metal shell of all electrical equipment should have reliable grounding devices, and the grounding resistance should not be greater than 4Ω.

6) The disassembly and assembly of the crane shall be carried out during the day. In case of severe weather such as strong wind, dense fog, rain and snow, the operation should be stopped.

7) Dismantlers should wear safety protection articles when entering the work site, and fasten their seat belts when working at height.

8) In the process of disassembly and assembly, if the operation cannot be continued for a short time due to unexpected circumstances such as abrupt weather change, sudden power failure, mechanical failure, etc., the disassembled parts must be stable and firmly fixed, and the operation can only be stopped after inspection and confirmation that there are no hidden dangers.

9) During crane installation, technical inspection must be carried out in stages. After the installation of the whole machine, the technical inspection and adjustment of the whole machine should be carried out, and the actions of each mechanism should be correct, stable, without abnormal sound, reliable braking and sensitive and effective safety devices; Under no-load condition, the allowable deviation of verticality between tower and foundation plane is 4‰. After passing the inspection in stages and the whole machine, the inspection records shall be filled in and delivered only after being reviewed and signed by the technical director.

10) The accessories and anchorage of the crane shall meet the following requirements:

① The mechanical strength of the anchorage point of the building to which the crane is attached shall meet the design requirements of the crane. The arrangement, mutual spacing and connection distance of the connecting rod system shall be implemented in accordance with the provisions of the factory instruction manual. If there is any change, it should be designed separately.

(2) When installing the attached frame and the attached pole, measure the verticality of the tower with theodolite and adjust it with the attached pole. The allowable deviation of verticality below the highest anchorage point is 2‰.

(3) When laying the attachment frame and the attachment bracket, the inclination angle of the attachment rod shall not exceed 10.

(4) Attached frames should be set at the standard joint of the tower to tighten the tower. When there is no diagonal brace, the diagonal of the tower should be reinforced.

⑤ When the tower is jacked up to the specified anchorage spacing, the anchorage device with the building should be increased in time. The height of the tower above the free end of the anchoring device shall conform to the factory regulations.

6. When the crane is running, always check the anchoring device. If looseness or abnormality is found, the operation should be stopped immediately. If the fault is not eliminated, you should not continue the operation.

⑦ When disassembling the crane, the corresponding anchoring device should be disassembled together with the tower descending process. It is strictly forbidden to dismantle the anchoring device before the tower falls.

Today, it is forbidden to install or dismantle the anchoring device when there is a strong wind of magnitude 6 or above.

Pet-name ruby anchorage installation, disassembly, inspection and adjustment, there should be someone who's in charge, work should wear a seat belt and safety helmet, and shall comply with the provisions of the high operation related to safe operation.

Attending attached rail crane, should improve the bearing capacity of rail foundation and cut off the power supply of walking mechanism, and should be set to block the movement of walking wheels.

1 1) After monthly or continuous heavy rain, the track foundation shall be thoroughly inspected in time, including gauge deviation, inclination of rail top surface, elastic settlement of track foundation, rail straightness and track passing performance. For concrete foundation, check whether there is uneven settlement.

12) the distribution box should be set in the middle of the track, and the power supply line should be equipped with phase-shifting and phase-breaking protection devices and emergency power-off switches. Cable reels shall be flexible and effective, and cables shall not be dragged.

13) When there are more than two cranes at the same construction site, the distance between any close parts (including lifting heavy objects) between the two cranes shall be kept at least 2m.

14) Before crane operation, check that the track foundation is straight and free from sinking, fishplate connecting bolts and spikes are not loose, and remove obstacles on the track, loosen the rail clamp and fix it.

15) Cranes with upper and lower control systems shall not be used at the same time.

16) operation, when the power failure or voltage drop, should immediately pull the controller to zero, and cut off the power supply. If there is a heavy object hanging on the hook, you should repeatedly use a slightly looser and tighter brake to make the heavy object slowly descend to a safe place.

17) During the operation, in case of strong wind or gust with magnitude 6 or above, stop the operation immediately, lock the rail clamp, release the brake of the slewing mechanism, and the boom should be able to rotate with the wind.

For light luffing cranes, the boom should be lowered and locked with the tower structure.

18) It is forbidden to overload the crane manned elevator, and its broken rope protection device must be reliable. It is forbidden to start the elevator when the crane is working. When the elevator is out of service, it should descend to the lower part of the tower, and don't hang in the air for a long time.

19) After the operation, stop the crane in the middle of the track, turn the boom to the downwind direction, and release the slewing brake. The trolley and counterweight should be in non-working state, and the hook should be raised to a distance of 2 ~ 3m from the top of the boom.

20) When stopping, reset the controllers to zero, turn off the switch in turn, close the doors and windows of the control room, lock the rail clamp after getting off the bus, fix the crane with the rail, turn off the main power switch and turn on the high-altitude indicator light.

2 1) Cantilever and non-attached jack-up tower cranes are not allowed to hang placards.

For more information about project/service/procurement bidding, and to improve the winning rate, please click on the bottom of official website Customer Service for free consultation:/#/? source=bdzd