14. 15. 1 tower crane selection and plane installation position
According to the needs of construction and production, the bottom 15-32 of this project is lower than the bottom 1. Considering the site situation, the location of tower crane is determined according to the general layout.
Different types of tower cranes have different installation, jacking, attachment, various disassembly schemes, debugging contents and safety measures according to the actual situation, which should be carefully considered and handled according to the specific situation.
14. 15.2 tower crane foundation
The soil quality of tower crane foundation should be solid, and the bearing capacity of foundation should be ≥ 1 10kP/m2. The location of the tower foundation and embedded parts shall be constructed according to QTZ63 jack-up tower crane and the foundation details in the appendix of the manual, and the concrete strength grade shall not be lower than C30.
14. 15.3 equipment configuration
According to the installation height of the tower crane and the weight of the heaviest component, install (disassemble) the required machinery.
14. 15.4 construction preparation
1. Laying and leveling roads on the construction site, removing obstacles, etc.
2. The user of tower crane and the person in charge of tower crane installation technology shall accept the concrete foundation of tower crane according to the technical requirements of foundation production, and the smoothness of the foundation surface shall not be greater than 1/500.
3. The tower crane driver shall inspect the tower crane, and the inspection contents are as follows:
(1) Whether the steel structure has cracks and desoldering;
(2) Whether the wire rope is firm and reliable, whether it meets the requirements and whether the rope head is reliable;
(3) Whether all circuits and electrical components are normal;
(4) whether the guide wheel of the climbing mechanism rotates flexibly and whether the clearance with the tower crane meets the requirements.
(5) jack-up hydraulic device is normal;
⑥ Soak the bolts and pins to be dismantled for rust removal, and remove the soil on the embedded parts;
⑦ The rotating tower crane should be carefully overhauled and maintained before installation, the deformed part should be repaired in time, and the whole machine should be painted if necessary.
4. Do a good job in personnel organization.
5. Prepare common tools, rigging and materials.
6. The technical director shall make technical disclosure to all operators.
7. The safety supervisor shall make safety disclosure to all operators.
8. The team should level the tower crane foundation (four corners), and its flatness should be controlled within11000.
14. 15.5 installation process
According to the requirements of the instruction manual of QTZ63 tower crane, the following installation procedures are formulated:
1. Installation of underframe: hang the assembled underframe on the concrete foundation, calibrate the underframe with a level, and tighten the anchor bolts.
2. Install the foundation section or standard section and check the verticality. Its verticality should be controlled within11000.
3. Lift a standard section with a crane, slowly lift it to the foundation section or standard section (pay attention to the steps and ladders on the standard section corresponding to the foundation section when installing), and tighten the connecting bolts around.
4. Install the walking platform and railing of the climbing frame on the ground, install the climbing mechanism and hydraulic pump circuit, add hydraulic oil, lift it outside the basic section and the standard section, adjust the guide roller, so that the gap between the roller and the tower is 2-5mm, and ensure that the climbing claw is placed in the groove of the steps of the tower.
5. Assemble upper and lower bearings, slewing mechanism, slewing bearing, platform, etc. Connect it into a whole on the ground, then lift it and install it on the tower section, and connect the lower bearing with the climbing frame and the standard section of the tower with pin shafts and high-strength bolts.
6. Installation of tower cap: connect a cross-arm pull rod (one on the left and one on the right) at the top of the tower, then lift the top of the tower and fix it on the upper support with four pins. Please note that the hypotenuse of the tower top is on the same side as the boom.
7. Installation of the balance arm: install the platform, railing, lifting mechanism and distribution box of the balance arm on the ground, connect two pull rods and fix them with iron wires according to regulations, connect the wires of all parts, then lift the balance arm and connect it with the upper bracket with a pin shaft, after connection, obliquely lift the balance arm to the installation position of the balance arm pull rod, and then unload the crane.
8. Lift the 2T balance weight to the specified position according to the regulations in the manual. See the professional installation drawing for specific construction.
9. Cab installation: After checking the electrical equipment of the cab on the ground, lift the cab to the upper bracket platform, and then connect the cab with the upper bracket platform with a pin shaft.
10. Assemble the derrick: assemble the derrick with corresponding pins according to the requirements of the manual. After the first section and the second section are connected, install the trolley hanging basket, fix the trolley and the hanging basket at the root of the boom with iron wire, then put the boom on a bracket with a height of about 1 m, so that the trolley and the hanging basket leave the ground, and then assemble other boom sections according to the requirements of the manual.
1 1. Assemble the hanger rod: assemble the hanger rod according to the instructions and fix it on the corresponding bracket of the upper chord.
Note: After assembly, check the tightness of each pin fit, whether the stop device works and whether the cotter pin is worn.
12. Installation of the boom: find the center of gravity according to the requirements of the manual, put on a lifting rope, tie a traction rope at both ends of the boom, and use a truck crane to stably lift the boom assembly to keep the boom in a horizontal position, so that the boom can be smoothly installed on the boom hinge hole of the upper bracket.
After the suspender is connected with the upper support, continue to lift the suspender, so that the head of the suspender is slightly lifted (use the wire rope of the lifting mechanism to pull up the pull rod through a group of pulleys and suspender pull rods at the top of the tower, so that the short pull connection plate is connected with the pull plate at the top of the tower by pins, and then adjust the height position of the long pull rod, so that the connection plate of the long pull rod can also be connected with the pull plate at the top of the tower by pins. Then slowly lower the suspender so that the pull rod is under tension.
13. Lift the balance weight: place the balance weight according to the instructions.
14, electrical wiring.
15. Thread the hoisting wire rope: lead the wire rope out of the drum, pass through the guide pulley at the top of the tower, bypass the pulley of the hoisting limiter, then lead it to the trolley pulley and the hook pulley, and finally fix the rope end on the arm head.
Remarks: If there are pillars in the foundation, the four pillars on the underframe must be installed before it can work.
Remarks: The disassembly process is the reverse of the installation process.
14. 15.6 debugging after installation
1, debugging work must be carried out under the guidance of professional engineers.
2, debugging content and order:
A torque limit b weight limit c height limit d amplitude limit
E slewing limit
3. The debugging data should be strictly in accordance with the data specified by the manufacturer, and the data of the old tower should be reduced.
4. The weight of the suspended object should be accurate.
5, adjustment method should carefully refer to the machine manual.
14. 15.7 safety precautions during installation (disassembly)
1, all operators must hold valid certificates, and those who have not obtained evidence shall not participate.
2, all homework personnel must obey the unified command of the commander in chief.
3. The commander-in-chief must obey the technical guidance of technicians and accept the safety supervision of safety supervisors.
4, homework personnel must wear safety helmet, high personnel must wear non-slip shoes, work in dangerous parts must fasten your seat belt.
5, all cranes must strictly abide by the safety operation procedures.
6. Drinking is prohibited during disassembly.
7. Concentrate on your work and don't joke and play at will.
8, cross homework up and down, pay attention to the tools and parts must be safe and reliable, to prevent falling cuts.
9, crane commanders should be familiar with the crane lifting performance, lifting weight and parts installation parts.
10, the commander should unify the gesture signal with the crane driver.
1 1. If the lifting height of large articles exceeds two meters, fasten the traction rope.
12, the sling used must comply with the safety regulations, and the center of gravity of the suspended component must be accurate and meet the requirements of the manual.
13. All bolts and pins must be installed on the assembled assembly and accessories in accordance with regulations to ensure safe use.
14. All bare wires in the operation area must be cut off and guarded by special personnel.
15, it is forbidden to disassemble the tower crane in case of heavy rain, heavy snow, fog and strong wind (wind speed reaches 8.3m/s).
16, work at night must have enough lighting.
17. Idle personnel are prohibited from entering and leaving the job site, and temporary protective measures should be taken when working along the street.
14. 15.8 jack-up scheme
After the installation of tower crane, it is necessary to jack up and increase the standard section. Matters needing attention in the whole jacking process:
Attention should be paid to before jack-up:
1, put the standard sections to be added under the boom one by one before jack-up.
2. Adjust the gap between the guide wheel of the climbing frame and the tower, preferably 2-3 mm. ..
3. The length of the slack rope is slightly greater than the total climbing height.
4. Before the cylinder starts to move, it is necessary to check whether the top beam is in the correct position.
5, test run before jacking, normal rear can rise or fall tower.
Attention should be paid to in the process of jack-up:
1, before the oil cylinder starts to move, it is necessary to check whether the jack-up beam is in the correct position and whether the jack-up upper part is in the balanced position, otherwise the front and rear sides of the balance tower body should be adjusted.
(Adjustment method: Adjust the position of the trolley so that the upper center of gravity of the tower crane falls on the position of the top beam. In actual operation, it is observed that the four-corner guide wheels on the climbing frame are basically separated from the standard chord of the tower, which is the ideal position).
2. When climbing, the boom can't rotate, and the oil cylinder is always at the specified pressure.
3, only allowed to act alone, it is forbidden to climb and other actions at the same time.
4. When the climbing sleeve is separated from the standard section of the tower, it is forbidden to lift heavy objects.
5. During jack-up, the boom should be kept in the front position (the standard section is introduced as the front).
6, jack-up process, slewing mechanism must be in an effective braking state.
7. If segments are added continuously, after each segment is added, the next standard segment will be lifted by the tower itself, and all the high-strength bolts between the standard segment of the tower and the lower support will be tightened.
8. The added standard section must be aligned with the existing standard section of the tower.
Jack-up procedure:
1. Lift a standard section and put it on the inlet beam. Adjust the position of the trolley so that the center of gravity of the tower crane falls on the position of the jack-up cylinder (the adjustment method is as above).
Item 1 can also be: hoist a standard section on the imported trolley, then hoist a standard section with the lifting trolley and move it to the position specified in the manual (20m away from the tower rotation center).
2. Push the top beam onto the steps of the tower (or put both ends of the top beam into the top block groove of the standard section).
3, start the hydraulic system, make the piston rod fully extended, and then slightly shrink the piston rod, make the crawling claw on the steps of the tower, and then all the oil cylinders are retracted, and the top beam is propped on the steps of the tower (or in the top block groove).
4. Start the hydraulic system again to make the piston extend out of the oil cylinder again. At this time, there is a space on the tower body to hold a standard section.
5. Using the rolling of the imported roller on the outrigger (or imported beam), guide the standard section directly above the tower, retract the oil cylinder until the upper and lower standard sections contact, and firmly connect the upper and lower standard sections with high-strength bolts, that is, complete the process of adding a section.
6. Retract the oil cylinder to contact with the upper and lower standard sections, and connect the upper and lower standard sections of the tower body firmly with high-strength bolts.
7. If you need to add festivals, repeat the process of 1-7.
After jack-up, attention should be paid to:
1, after adding segments, rotate the boom to different angles, and check the fastening of high-strength bolts at each joint of tower section, especially the fastening of connecting bolts between lower support and tower body. (Which main chord of the tower is located directly below the balance arm, tighten the main chord bolt from bottom to top).
2. After the tower crane is assembled, lower the climbing frame to the bottom of the tower and fix it, so as to reduce the center of gravity of the whole tower crane and reduce the windward area.
3. When the tower crane is segmented, set the operating handle to zero and cut off the power supply of the hydraulic system.
Safety precautions:
1, the wind force is greater than level 4. Jack-up is prohibited.
2. All operators must hold valid certificates.
3, strictly abide by the safety operation procedures, process specifications and technical disclosure.
4, all homework personnel must wear safety helmet, wear non-slip shoes, wear a seat belt when necessary.
5, tools and bolts used in the operation should be placed in a safe and reliable position, to prevent falling injury.
14. 15.9 attachment scheme
1. According to the building height and construction height of this project, set up an attachment frame, the first attachment frame is 2 1 m from the ground, and then every12m.
2. The distance between the connection point and the center of the tower crane is 3.5m. ..
3. The arrangement of the upper and lower connecting rods should be staggered.
4, the attachment point to bury iron.
5. Procedure:
(1), wrap the ring beam outside the tower, connect it with bolts, and then lift it to the attachment point.
(2), adjust the bolt, make the top block can top tight tower.
(3), lifting poles, and adjust the adjusting bolt, make it meet the length requirements.
(4) Check the verticality of the tower crane axis with theodolite, and its verticality shall not exceed 2/ 1000 on the overall height.
(5), need to attach for many times, the method is the same as above.
6. Technical requirements: According to the actual situation of tower crane and building location on site, the following technical requirements are put forward:
(1), the strength of the attachment point should meet the load of the tower crane on the building, and if necessary, steel bars should be added or the concrete grade should be improved.
(2) The attached hanging basket should be set at the standard joint of the tower as far as possible, the attached frame should tighten the tower, and the inclination of the attached rod should be controlled within 10.
(3) Make a 30-degree groove at the butt joint of the bar. The weld thickness should be greater than 10mm, and the weld thickness of the bearing should be greater than 12 mm. ..
(4) The included angle between the attachment rod and the wall should be controlled between 45 and 60.
(5) The free height above the anchorage point shall be controlled within the height specified in the manual.
⑥ After attachment, use theodolite to test, and ensure the verticality of the tower by adjusting the length of the attachment guy and the top block (the verticality error between the tower axis and the bearing surface is not more than 4/ 1000, and the verticality of the tower below the highest anchorage point is not more than 2/ 1000), and make records.
14. 15. 10 Remove the connecting frame.
1. Set up the operating platform under the attached hanging basket with steel pipes and springboard, and support the platform during erection.
2. Set walkways or other auxiliary lifting devices according to buildings.
3. When the walkway is demolished, the wall-attached support can be directly transferred to the building and then to the ground.
4. When using other auxiliary lifting equipment for disassembly, the stay rod near the floor end should be fixed with a lifting rope first, and then the stay rod pin near the floor end should be reset; Fix the stay bar at the tower end with rope, slowly lower the support bar after removing the pin, let the auxiliary lifting device bear the force, and lift the support bar to the ground with the auxiliary lifting device. Remove the support rods in turn in the same way.
Step 5 fold the attached basket
Remove the accessory basket.
Cooperate with the hydraulic jacking mechanism to lower the climbing frame to its connected position.
Fix the attachment basket at the lower end of the climbing basket with 8# lead wire and wooden wedge.
Note: When fixing the accessory basket, do not affect the tower descending work.
After multiple disassembly, the next attachment basket can be fixed on the last attachment basket. As the tower descends, the attachment basket will descend to the height where the tower is removed, and finally the attachment basket will descend to the ground by the crane.
14.15.11Problems needing attention in tower crane operation
Due to the requirements of construction and use, there will be unsafe factors in the construction process of tower crane boom, so the construction requirements are as follows:
(1) Always check the appearance of tower crane and record the wear and tear of structural parts, electrical devices, transmission mechanism and wire rope. If there is any potential safety hazard, it should be reported in time or repaired and replaced in time.
⑵ Do daily maintenance and check the fastening (tightening) of standard section connecting screws once a week. Always check the appearance of tower crane and record the wear and tear of structural parts, electrical devices, transmission mechanisms and wire ropes. If there is any potential safety hazard, it should be reported in time or repaired and replaced in time.
(3) The Tower Company must obey the unified command at the site, obey the signal and not go its own way.
(4) tower crane operation must abide by the following principles:
1. Before lifting, check the hoisting, slewing, walking and other mechanisms, as well as brakes, limiters and protective devices. Normal construction (lifting objects) can only be started after it is confirmed to be normal.
2, the driver should know the weight of the lifting object, shall not be overloaded.
3. Drivers and commanders should cooperate closely and communicate in time to prevent misoperation.
4, the driver should be in the process of lifting sound signal.
5. When the tower crane is running, no one can be under the crane. When lifting the crane, the driver should try to avoid the crowd, and the crane should not pass above the crowd.
6. No one is allowed to rise or fall with the hanging object.
7. When lifting large formwork and steel formwork, the formwork must be completely separated from the concrete wall, and all kinds of connections must be completely lifted. The side of the suspended formwork shall not be stuck by other formwork or objects. Otherwise, lifting is not allowed. In the process of lifting, the tower crane driver should keep in touch with the following operators or tower crane commanders at any time. If the hoisted object is stuck by steel bars, shelves or other objects, it is forbidden to continue lifting, and it must be stopped immediately before lifting.
8, tower crane all kinds of limit it is forbidden to dismantle or change.
9, night construction should have enough lighting.
10, special type of work, must hold relevant certificates to operate the corresponding work. Non-professional mechanical operators are not allowed to use or operate machinery at will. Tower crane, construction elevator, concrete mixer, electric saw (circular saw), electric welding machine, vibrator, external climbing electric hoist, various distribution boxes (panels and cabinets), hand-held power tools, gas cutting (welding), etc. It must be operated and used by professionals and special personnel with corresponding certificates.
In the process of operation and use, written disclosure and corresponding operating procedures and specifications must be strictly observed. All consequences of illegal operation and use shall be borne by yourself.
1 1. wall attachment measures: attach a layer of wall in advance as required.
12, all kinds of limit devices shall not be changed at will, and shall be implemented in strict accordance with the specified requirements. Lightning protection and grounding must be tested frequently.
13, hook workers should strictly implement the principle of "ten don't lift". Understand the weight of the hoisted object, and the hoisted object shall not exceed the weight specified by the tower crane, grasp the center of gravity of the hoisted object, and bind the hoisted object according to the regulations, which must be firm. When the hoisted object has a large span, it must be safe and reliable.
14. In case of strong wind (above level 5), lightning and rainstorm, the tower company, bell man and hook man are not allowed to lift objects again. After the storm, it is necessary to strengthen inspections and eliminate hidden dangers in time.
15. The trolley for lifting heavy objects shall not exceed the west fence and the south fence, and a protective shed shall be erected on the sidewalk with steel pipes and wooden boards.