Tower crane fall prevention solution?

Tower crane installation and dismantling

1. Determination of the plane position of the tower crane

When selecting the QT80 tower crane, you must strictly follow the crane operating instructions and instructions during the installation process. All current construction and design specifications shall be implemented. In accordance with the principles of selecting a tower crane to meet construction requirements and facilitate installation and disassembly, and taking into account the actual conditions of the project, the tower crane is arranged outside the foundation pit (see the attached picture for detailed positions). At the same time, the following points should be noted:

1 , perpendicular to the direction of the tower crane unloading arm, the center line of the tower crane foundation should be no less than 2.8m away from the decorative outline of the building (the width of the scaffolding is 1.2m).

2. Along the direction of the tower crane unloading arm, the distance between the center line of the tower crane foundation and the side line of the building shall not be less than the arm length.

2. Tower crane installation

The installation of tower crane must strictly comply with the relevant safety operating procedures.

1. The tower crane assembly sequence is: install the standard section → hoisting set → install the slewing bearing assembly → install the slewing tower body assembly → install the tower top → install the balance arm tie rod → install the driver’s cab → install Lifting arm assembly → Install the lifting arm rod → Equip the counterweight.

2. When installing the tower crane, a 25T truck crane can be used directly for assembly on the ground.

3. Before pouring the tower crane foundation concrete, embed the standard sections of the tower crane foundation.

4. Before installing the lifting arm, a 2.32t balance weight must be installed on the balance arm before the arm is broken, but it is strictly prohibited to exceed this amount.

5. The installation position of the tower crane at the construction site must ensure that the maximum rotating part of the tower crane, such as the boom, hook, etc., is at a safe distance of more than 5m from the transmission line.

6. Embedded parts for supporting rods in buildings can be embedded in pillars or cast-in-place concrete wall panels. The embedded steel plates should be close to the floor slabs, and the distance between them should be no more than 20cm. should.

7. When installing and fixing the attachment rods, the verticality of the tower structure must be checked with a theodolite. The vertical deviation shall not be greater than 3‰. If the tower body is found to be deflected, the length of the attachment rods should be adjusted. , for straightening, the attachment rod must be installed securely.

8. During the use of the tower crane, all parts and connections of the anchoring device should be carefully inspected frequently.

3. Tower ceiling lifting section

First preparation:

1. Check the performance of the hydraulic pump and refuel the fuel tank as required.

2. Preparation before jacking: ⑴ Clean each standard section, apply butter on the joints of the standard sections, and line up the lifting arms when the standard sections are in the jacking position. ⑵ Loosen the cable length slightly greater than the total jacking height, and tighten the cable. ⑶ Rotate the boom to the front of the jacking frame. ⑷ Prepare the introduction roller on the introduction platform.

3. Trimming of the tower crane

⑴ First, move the tower crane to the trimming reference position and lift a standard section at four times. ⑵ Remove the four legs of the support and the connecting bolts of the standard section. ⑶ Push the control lever of the hydraulic jacking system to the jacking direction to lift the frame to the position where the lower support leg has just separated from the main chord of the tower body. ⑷Slightly adjust the trim position of the trolley so that the lower support legs and the main chord of the tower are in a vertical line. At the same time, the clearance between the eight guide wheels of the frame and the main chord of the tower is basically the same. ⑸ Operate the hydraulic system to lower the frame, and connect the connecting bolts between the lower support and the standard section. ⑹Make a clear mark on the trim position of the load-carrying trolley.

Second lifting operation

1. Lift a standard section to the square of the introduction beam of the frame, install four introduction rollers on the lower end of the standard section, and slowly lower the hook. Make the introduction roller installed on the standard section just fall on the introduction beam, and then take off the hook.

2. Lift another standard section and drive the load-carrying trolley to the lifting balance position.

3. Use the slewing brake to brake the upper part of the tower crane.

4. Remove the 8 high-strength bolts connecting the top of the tower to the lower support.

5. Jack up the upper structure of the tower crane in two steps until it is just enough to introduce a standard section above the tower body. Guide the standard section on the beam of the frame into the tower directly above the tower body. Slightly retract the oil cylinder, place the newly introduced standard section on the top of the tower, remove the introduction roller, and use 8 pieces of M36 high-strength bolts to securely connect the upper and lower standard section connectors with a pretightening torque of 2400KN.m.

6. Retract the oil cylinder again, place the lower support on the top of the new tower body, and use 8 pieces of M36 high-strength bolts to securely connect the lower support to the tower body.

7. Repeat the above steps until all required standard sections have been added.

8. After the tower crane reaches the required working height, rotate the boom to different angles. When the main chord rod is located directly below the balance arm, move the rod from bottom to top. All nuts are tightened.

IV. Tower crane trial operation and test

After the complete machine is installed according to the steps, check the lateral verticality of the tower axis to the supporting surface in a windless state , the allowable deviation is 4/1000, then turn on the power of all circuits according to the requirements of the circuit diagram, try to start each mechanism for operation, check whether each mechanism operates correctly, and check whether the wire ropes everywhere are in normal working condition and whether they are in contact with the structural parts. Friction and all abnormalities should be eliminated.

After the tower crane is assembled, the following tests should be carried out in sequence

1. No-load test

Each mechanism should be run several times separately, and then comprehensively done three times. Action operation, no abnormality should occur during the operation, otherwise the fault should be eliminated in time.

2. Load test

Lift 25, 75 and 100 of the corresponding rated lifting weight at the maximum amplitude and the maximum amplitude corresponding to the maximum lifting weight, respectively, according to the requirements of Article 1 test.

If the tower crane is to be used after installation, the safety devices must be adjusted according to relevant requirements. Tower crane safety devices mainly include: stroke limiter and load limiter. The stroke limiters include: launch height limiter, rotation limiter and amplitude limiter; the load limiters include: lifting moment limiter, lifting weight limiter, and anemometer.

5. Inspection items after tower erection

Inspection items

Inspection content

Underframe

Inspection location Tightening of the foot bolts

Check the safe distance between the transmission line and the maximum rotating part of the tower crane and check the cable passing condition to prevent damage

Tower body

Check the tightening condition of the connecting bolts of the standard section

Sleeve

Check the connection condition of the support pin in contact with the standard section during jacking to see if it is flexible and reliable

Check the fastening of walkways and railings

Upper support

Lower support

Driver's cab

Check the connection with the slewing bearing The bolt tightening condition

Check the cable passage

Check the tightening condition of the platform and railings

Check the connection with the driver's cab

It is strictly prohibited to store lubricating oil, oily cotton yarn and other flammable items in the cab

Top of the tower

Check the installation status of the lifting arm and balance arm pull rod

Check the installation of escalators, platforms, and guardrails

Ensure that the lifting wire rope is correctly wound

The lifting arm

Check the connecting pins, washers, and The correctness of the opening installation

Check the installation and operation of the load-carrying trolley and the fastening of the loading rail

Check the winding and fastening of the lifting and luffing wire ropes

Balance arm

Check the fixation of the balance arm

Check the installation of the balance arm guardrail and walkway to ensure that there is no debris on the walkway

Hand Tools

Check whether the automatic magnification change device and the hook's rope-off prevention device are safe and reliable

Check whether the hook set has any defects that may affect its use

Start the inspection The specifications and models of lifting and luffing wire ropes should meet the requirements

Check the wear and tear of the wire ropes and the fixation of the rope ends

Mechanisms

Check the installation and installation of each mechanism. Operation status

The brake clearance of each mechanism is adjusted appropriately

Check the traction mechanism. When the trolley runs at the minimum and maximum amplitude, there should be at least 3 safety rings on the drum wire rope

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Check whether the tightness of the wire rope head is loose

Safety devices

Check whether each safety protection device is adjusted according to the requirements of the instruction manual

Check the installation and tightening conditions of all escalators, railings, and rest platforms on the tower crane

Lubrication

Check the lubrication conditions according to the instruction manual and perform lubrication work

6. Tower Crane Disassembly

1. The order of tower crane disassembly and tower crane assembly is reverse.

2. When dismantling the tower crane on the ground, you can directly use a 20-ton crane to gradually dismantle each component in the order of disassembly.

4. When dismantling, be sure to synchronize the landing tower body and the removal of the attachment rod.

7. Safety measures

1. The wind speed should be lower than 8m/s when installing and dismantling the tower crane.

2. Workers at the construction site must wear safety helmets and safety belts when working at heights. Dual commands are provided on the ground and in the foundation pit.

3. During the hoisting test, observe the settlement of the tower crane foundation, whether it is tilted, and whether the tower is vertical. If there are any problems, deal with them in a timely manner.

4. The relevant provisions of the "Tower Crane Operation and Use Regulations" must be strictly implemented, and drivers and crane workers must hold certificates to work.

5. It is strictly prohibited for drivers to operate the aircraft after drinking.

6. For night operations, the construction site must be equipped with adequate lighting facilities.

7. When abnormal phenomena are found in the tower crane, the machine should be shut down and the power supply should be cut off. The fault should be clarified and eliminated before use.