prevent the sudden incident in the operation of tower crane correctly
A tower was suspended at the shaft installation site to perform the lifting and unloading task. When it lifted a connecting arm weighing about 6 T Derrick, it caused the aircraft to dump to the right during the rotation of the main arm.
The main arm touches the ground slightly, the front and rear leg support pads are broken, the piston rod of the leg cylinder is severely bent and deformed, and the front and rear leg expansion arms are deformed and broken; Left front and rear leg cylinder off the ground; Frame engine support hoist fracture; Battery's broken. Fortunately, the driver jumped out of the cab in time. How to prevent the sudden incident in the operation of tower crane correctly?
(1) The correct prevention of Tower lifting should strengthen the education of the driver's safety operating rules so that he can master the relevant tower lifting technology skillfully.
(2) The correct prevention of Tower lifting should strictly comply with the requirements of the "Regulations on the Safety Supervision of Special Equipment" and other laws and regulations. Drivers must be certified for duty, and regular inspection and supervision of vehicles should be carried out.
(3) For the correct prevention of Tower lifting, it is necessary for the lifting unit to carry out detailed inspection and demonstration of the operation items on the special site, and to formulate a detailed operation plan. It is also necessary to arrange full-time personnel to conduct on-site command.
(4) Install torque limiters on vehicles to fundamentally eliminate the potential for irregular safety hazards due to overload.
(5) When the tower crane is properly prevented from choosing a hanging site, it must choose an open area that is not soft, collapsed, and has a drain cover and other flat and solid areas.
(6) Maintain and maintain the vehicle to ensure that the vehicle is in a sound technical state. In particular, it is necessary to constantly check the main arm, leg cylinder, support pad, variable width cylinder and other parts for cracks and oil leaks.
(7) Before lifting, the driver must estimate the weight of each and other hanging objects, and it is forbidden to lift them blindly.
The Origin and Development History of the Flat Head Tower
The flat-headed tower crane originated in Europe, and its name is derived from the translation of the flat-top power crane Crane, and it is also called the topless tower crane crane. The design idea and prototype of the flat head tower crane can be traced back to the 1960s.
At that time, the shape of the tower crane developed by the French Richer company was close to that of the current flat head tower crane. For example, its X1290 and GT series tower crane tower head is shorter, usually No more than 4m, Only slightly higher than the boom and balance arm.
However, strictly speaking, these tower hangers are different from the current flat tower hangers. Although the tower heads are relatively short, they can still distinguish tower heads, balance arms, and pull rods.
The real flat head tower crane was born in 1975. The Swedish Linden company first proposed the concept of a flat head tower crane, and took the lead in introducing the Linden 8000 flat head tower suspension mode system. The cranes of different models of flat head towers can be interchanged. The Linden flat head tower crane does not have a tower head in the traditional sense, and the pull rod is cancelled.
The upper structure is horizontal and rigid in shape. There is no hinge connection between the tower head, balance arm, boom and pull rod of the traditional tower crane. way. It can be said that the appearance of Linden's flat head tower has opened the prelude to the development of the flat head tower.
The development of flat head towers in foreign countries has not been generally accepted by users for a long period of time since the introduction of flat head towers, because people have been used to tower cranes with tower heads in their hearts, and they think that tower suspension towers are natural things. Some even think that there is no tower head or pull rod on the tower, and the structure is unreasonable and unsafe.
The structural characteristics and unique advantages and disadvantages of flat head tower crane
Structural characteristics of flat head tower hanging:
The most prominent structural features of the flat head tower hanging: there is no tower head and pull rod, which is also the origin of the flat head tower. Because of this special structural form, the flat head tower is qualitatively different from the tower with a tower head, which also determines the unique advantages and disadvantages of the flat head tower.
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Advantages and disadvantages of flat head tower hanging:
Compared with the horizontal arm with the tower head and the pull rod, the stress and connection mode of the flat head tower crane are different. After the tower is erected, whether it is working or not, the stress state of the upper and lower main strings of the flat tower boom and the balance arm remains unchanged.
The upper strut is mainly pulled, the lower strut is mainly pressed, and there is no influence of the alternating stress. The mechanical model is single and concise.
It is based on this point that the connection design of the flat head tower crane arm is more simple, and it is very convenient for the rapid disassembly between the arms. Most of the modern flat head tower crane arms use the space truss structure with a regular triangular section. This force condition is also considered.
The upper string is connected by a pin shaft to withstand the tension, and the lower string is subjected to pressure by the end surface of the junction. In this way, the connection of the lower string is very simple, relying only on two positioning pins and locking bolts.
At the time of installation, the upper pin shaft is connected first, and then the lower arm joint is lowered. The two locking pins are automatically in place and the bolts can be put on. The arm joints are mainly connected by a large pin shaft of the upper string, which saves both effort and time. This is the flat head. One of the characteristics of the tower crane.
Analysis and Solution of Common Fault of Engineering Machinery in Winter
In winter, the weather is cold, and the diesel engine is often subjected to "three resistance" events, namely, air resistance, water resistance, and material resistance. The "three resistance" incident is also a common failure of the engineering machinery in winter. Then, how to eliminate this failure one by one? Please see the usual fault analysis and solution for engineering machinery in winter.
Air resistance:
When air resistance occurs, exhaust can be used to start the diesel engine. If the pipeline is intact, the air can be discharged. If there is always gas discharge, the pipeline leaks.
According to the direction of the oil road, check the joint of the pipeline one by one, find the leak site, seal it well. If high temperature air resistance occurs, attention should be paid to check whether the exhaust valve on the oil tank cover is working properly.
Water resistance:
When water resistance occurs, the exhaust pipe continues to smoke, and a total of water droplets can be received from the exhaust pipe. This phenomenon shows that there is water in the fuel tank, and there may be a lot of water in the bottom layer.
At this point, the bottom of the fuel tank should be released and the diesel engine should be continuously started. If the water resistance failure is eliminated, the judgment is correct; If it can not be ruled out, the cylinder pad should be searched for leakage failure.
Material resistance:
When biological resistance is issued, the method of pushing and pulling the handle of the oil pump can be used to continue the inspection. When the handle of the pull oil pump feels a lot of resistance, it can focus on checking the oil supply line between the fuel tank and the oil pump. The blocking site may be the oil supply pipe inlet or the fuel filter: If the pump is pushed, the resistance is greater.,
Can focus on the almond hand oil pump to the fuel supply line of the injection pump, the blockage site may occur in the fuel filter. After removing the material resistance, the fuel supply system(including fuel tank) should be thoroughly cleaned.
In the cold winter, ice resistance occurs in pipelines and pipe joints. Warm pipelines and melt ice can be used without finding the exact part of the ice.
