How do tower crane grow?

Answer 1

Truck of 50t is needs when crane is installed. It takes time to hoist with truck if we can coordinate the steps of installation and assembly properly and assign crane-installed personal reasonably and coordinate the relation between aisle and installation spot.

5.1Attention of assembly

a. Installation of crane can be carried out when the wind is below 4 grades.

b. abided by the process of setting up crane.

c. Pay attention to the choice of hanging points; choose handling devices which are of proper length and liability according to the hoisted parts.

d. All dismountable pivots of every crane component bolt for tower and nuts are special parts, clients can not replace them at will.

e. Prepare all protective devices before installation and carry out security examination when necessary.

f. Installation location of standard section can not change at will; otherwise installation can not be carried out.

g. Reference dimension of crane installation site (fig.19)

h. Installation location of crane worksite must ensure the distance of above 5m between max swing section of lifting-jib and hook way from wine.

i. Prepare for the commonly used tools such as lifting devices, crossties, ropes, bights

5.2 Foundation and ballast

This crane adopts holistic concrete foundation or is used together with ballast. Sol of foundation should be massive. Resistant force of foundation should not be less than 200N/M2 ,Intensity grades of concrete is C30(GB50164-92).The resistance force of concrete foundation should not less than 30t/ M2 ,the flatness error of concrete foundation should can not exceed 1/500,Ballast is made of cast iron or concrete. The whole weight of foundation and ballast should not be less than 50t no matter what kind of ballast is used.

5.3Ground device

Ground of crane lighting rod and protective grounding should conform to related regulations, and the material for grounding, installing and maintenance are not supplied by factory.

5.3.1 Connect cable of grounding protective device with bolts of any main rod and clean the paint of bolts and nuts.

5.3.2Underbed on the ground can not be used for lighting rod of grounding.

5.3.3 The resistance of protective lighting device can not exceed 4.

5.3.4Grounding device should be installed by professionals because resistance ratio will vary largely with time and condition. And it needs instrument with light efficiency and precision to measure resistance. Check grounding wire and resistance periodically.

5.4Installation process of crane

5.4.1 Installation of under bed and put it on the platform of concrete foundation. install press plate and screw the foundation bolts, and measure the bracket parallelism of four lips and four bottom plate and foundation to level within 1.6mm.If the error exceed 1.6mm,we should adjust the surface between bottom plate and foundation to level with wedge and iron plate. Keep the wedge fixed firmly .don not allow the wedge to loose and screw grounding bolts again.(double nuts resisting loose)

5.4.2 Installation of reinforcing sections standard sections and climbing frame

Reinforcing section is hoisted to climbing frame. connect it to climbing frame with 8 special bolts and 16 nuts and hoist two reinforcing sections again (the side with pedal of tower section should be parallel to the direction of installing counter-jib)Hoist climbing frame after it is connected by bolts of standard sections to put climbing claws of climbing frame on the pedal of reinforcing section. Before hoisting climbing frame, adjust dimensions of 16 climbing guide wheels max.

Attentions: Put hydraulic climbing pump station on the climbing frame platform near climbing cylinder.

5.4.3Assembly of swing mechanism

Lower bracket, swing bearing and upper bracket (include swing mechanism) are connected into integration with bolts when they are dispatched from the factory. There are four hoisting ears on upper bracket. Hoist this assembly parts on the climbing frame, the rabbet of standard section and four main rods on the tower bracket and connect lower bracket and connect lower section to standard section with 8 standard section bolts of M27.Then install the working platform of upper bracket.

Adjust the gap between sixteen climbing guiding wheels and crane main rod to 2-3mm.

Attentions: gap adjustment of climbing guiding wheel and standard section should be made before installing tower head.

5.4.5 Installation of tower head

Before hoisting install the platform of tower head, guard rail and escalator.(to install counter-jib conveniently, we can also install two pull rods of counter-jib on each sides of tower head.)Then hoist tower head to swing tower and connect swing tower and upper swing platform with four pivots. When hoisting, the vertical side of tower head should face to the orientation of lifting-jib.

Install swing tower and upper bracket first on the ground if permits.

5.4.6 Installation of counter-jib (shown in fig 21)

Assemble counter jib on the ground and install lifting mechanism, electrical control case, resistance box and pull rod of counter-jib to counter-jib and connect them formally and hoist counter-jib (four lifting ears for installation on counter-jib)

Connect counter-jib to swing tower with pivots and install opening pivots, then hoist counter-jib gradually until pull rods of counter-jib are articulated with pivots and install split cotters. then put counter-jib down slowing ,hoist a piece of counter-weight of 1.5t again and install it at the end of counter-jib .sketch map of pull rods of counter-jib is shown. Sketch map of counter weight is shown .

5.4.7Installation of hoisting box

Hoist hoisting box to the front of right platform of upper bracket after the electrical equipments in hoisting box are installed completely. Aim at the position of upper hole of ear-plate and then connect it with three pivots and install split cotter.

5.4.8 Installation of lifting-jib (shown in fig.22)

Assemble lifting-jib on the level crossties near tower crane. Stop lifting-jib and put it on the crossties with the height of 0.6m.Put derricking trolley device to the min range of lifting-jib root and tighten it firmly with iron wine and frap rope of derricking trolley. Assemble pull rods of lifting-jib as shown and connect the pull rods to hanging points with pivots.(The hanging points of rigid pull rod of lifting -jib should be at the third and seventh jib from the root of lifting -jib)install split cotter, put it in fixed bracket of upper pull rods of lighting-jib and tighten it with iron wine check whether electrical circuit of lifting-jib is in good condition or not.

5.4.9 Install counter-weight

The total-weight is 9 t,6 pieces, each pieces are 1.5t. After hoisting, according to requirement, wind lifting rope. The rope comes out winding drum of lifting mechanism .firstly, wind over the upper guide pulley of tower head .Secondly, pass the root pulley of cargo boom, then to the derricking trolley and hook pulley block. Finally, then end of rope is fixed on device of cargo boom top.

5.4.10Electrical installation and debugging

5.4.10.1eletrical installation

a. after installation completely ,electric can be installed, referring to principle figures. External wiring diagrams, controlling wiring diagrams. Join up the circuits of controlling and power cable, brake cable and safety device, grounding device, obstacle light, searching light anemoscope etc.

b. before supplying electricity, check electrical system and conform to the requirements.

c. all circuit must be correct. Cable needs to be fixed, should be mounted reliably to avoid destroying cable when crane is moving.

d. before electricity, insulated check should be done. The main circuit and controlling circuit's dielectric resistance to ground is more than 0.50hm.ground resistance for tower should be below 4OHM.

e. main cable(ground and hoisting box's cable)should be through guard ring before interring hoisting box and reserve appropriately length to prevent cable when crane slews one and half circle and crane is climbing.

f. put all operating mechanism of hoisting box on safety position and put main switch on power failure position;' finally connect power cable of ground.

5.4.10.2

a. turn on the power supply the electricity for hoisting box to be sure that three-phase power is three-phase balance and the voltage is 380±10％（ground electrical not supply enough capacity to make sure motor's normally）

b. loosen height limiter and derricking limiter ,coordinate machine installation ,wind rope of lifting trolley.

c. debugging of lifting mechanism

Firstly operate lifting handle, then observe the conditions. When derricking handle pulled inward the hook moves upward. Otherwise the hook moves downward if not adjust the phase order of power for lifting motor.

d. after lifting debugging completed operate swing handle, and derricking handle respectively. Swing handle pull award trolley goes inward otherwise go outward. if not adjust, the phase order of each power should.

4.4.10.3attentions

a. after supplying electricity to hoisting box,(before turn on the air switch)obstacle lamp and lighting of hoisting box can be supplied electricity by switch on platform. The fan can get power from socket.

b. when start upon button, each hardly must zero adjust. The total contactor 2cjust gets electric self-protection.

c. when cargo boom swing right,(or left), it can't swing left(or right) at once 8s internal required. After swing handles zero adjustment, it can't brake immediately 8s internal also required.

5.4.11 after lifting two standard sections, install bevel brace rod.

Lifting process should be operated below four wind scale. Before climbing upper mechanism should be in braked condition and not allowed to swing.

In climbing process, crane can't do hoisting except for installation itself. If hydraulic climbing system is out of order, stop climbing at once. Withdraw oil cylinder, check obstacles and breakdown of oil circuit system.

5.4.11.1 Preparation before climbing

a. fill hydraulic pump with oil in regular pump station

b. clean each of standard section , seat butter on upper standard section .line up the standard sections that are going to be added to tower in a row under cargo boom lying on climbing position. Firstly, install strengthen section in order, then install standard section unrevised. It can save time in the whole progress of adding section without swing mechanism.

c. swing cargo boom to front of climbing frame and counter-jib lies back of frame (climbing oil cylinder lies rear of frame).

5.4.11.2 Climbing operation

a. hoist the standard section and put it on external jib

b. disassemble high strength bolts of M27 between lower pedestal and standard section. put two axial heads of climbing beam in grooves of pedals precisely and hold it uprightly. Let climbing beam as near tower as possible. keep it possible in a level with longitudinal axis of oil cylinder, start up hydraulic system and let piston rod stretch out 20-30mm.seperate barely the surface of lower bracket and the standard section, then hook moves outwards from root of arm at the same time. when the gap between 16 guide wheels around climbing frame and tower is basically symmetrical, stop the derricking trolley (driver must remember the balance position precisely)

c. continue to start the hydraulic system to stretch out piston rod. withdraw piston rod slightly and put guide claw on the pedal of standard section ,then piston of oil cylinder withdraw completely .emplace the axial ends of climbing beam renewably and accurately in groove of the previous group of pedals of standard section and hold it uprightly again. Stretch piston rod of oil cylinder again until there is space for a standard section at the top of tower. Standard section can be pulled to the right top of tower by rolling wheel. Locate dummy club of standard section and withdraw oil cylinder dummy clubs of upper and lower standard section are connected rightly. At this time, conjunct upper and lower standard sections firmly with 8 reinforcing bolts of M27.

Demount rolling wheel and adjust the stretching length of oil cylinder. Connect lower bracket with standard sections firmly to complete the work of adding a standard section. if several standard sections need to be added continuously, repeat the process several times according to above steps.

Attentions:

Swing mechanism brake is needed in the process of climbing. Brake lifting-jib and prevent lifting-jib from swing to make it sure that the lifting-jib and pulled standard section come in the same direction.

If several standard sections need to be added continuously, each main rod of tower and lower bracket must be connected with bolts of M27 after adding a section and before hoisting the next section, if section are not continued to added, the 8 bolts with high strength between lower brake and standard section must be connected well.

Pedals of added standard sections must be adjusted well to the existing standard sections.

Professional personnel need to hold climbing beam upright and make it sure that axle ends in pedal grooves are in its precise position in climbing process for safety.

5.4.11.3 Install 4 inching supporting robs

After adding the standard sections, tighten 8 bolts between lower bracket and standard sections. Install upper ear bracket of four motive supporting rods of the second section. Then connect 4 inclining supporting rods separately to the direction of diagonal line between under bed and tower pivots.

5.4.11.4

After adding section, slew jib frame to different angle to examine the tightening state of each connection point of tower, under bed, reinforcing section and ground bolts. (Tighten the nut when the main rod lies under the counter-jib and in this way, tighten all nuts down to up, and use double nuts to prevent loosing for connection)

At this time, the whole installation of crane is completed. But perpendicular for tower should be checked and the allowable error is 2/1000. And then crane gets into normal working state after debugging. Sections can be added in the above mentioned way if necessary. Put climbing frame down to the bottom of tower or attaching frame and tighten it after the climbing work is accomplished.