CN106276631A - A kind of roofing device for hoisting and crane and the method for dismounting of crane arm - Google Patents

Abstract

The invention discloses a roof hanging device and a method for disassembling a crane and a boom. In order to better fix the roof hanging device, the invention passes the basic steel beam on the roof hanging base through the fastening bolts of the girder plate penetrating the roof Fixed, and a parallel pressure plate is set to clamp and fix the foundation steel beam and the beam plate, so as to reduce the stability when the roof crane is loaded with gravity and make it move more smoothly. A floor pulley is installed at the contact intersection of the roof, and the lifting wire rope installed on the tower crane itself passes through the floor pulley and the boom to keep the boom in balance, and is pulled by the hook on the roof crane. , to disassemble the boom smoothly and quickly. This method is especially suitable for the disassembly of the super-long boom. After the boom is disassembled, the roof crane device can be used to adjust the balance The assembly, jacking frame assembly and standard section are disassembled in sequence, the disassembly process is simple and smooth.

Description

A kind of roof hanging device and dismantling method of crane and boom

technical field

The invention relates to the technical field of tower cranes, in particular to a roof crane device and a method for disassembling a crane and a boom.

Background technique

With the rapid development of modern construction, there are more and more super high-rise buildings, the height of the whole building can reach 600 meters, and the building floor area is relatively small. The tower cranes (referred to as tower cranes) used in the construction of super high-rise buildings are generally of the internal climbing type. The installation of internal climbing tower cranes must be fixed and raised between buildings or core tubes. After the tower crane completes the construction task, the internal climbing tower crane must be disassembled to the ground. Now, the tower crane is disassembled by installing a roof crane (roof crane for short) on the top structural column or beam of the building. When dismantling the tower crane, sometimes due to the limitation of the roof site conditions, the roof crane cannot directly lift the center point of the tower crane boom. When the center point moves backward, the tower crane boom breaks away from the tower body. Finally, the center of gravity of the front end is downward, and the rear end of the boom is tilted upward, so that the roof crane cannot be disassembled normally.

Contents of the invention

Aiming at the deficiencies in the above-mentioned technologies, the present invention provides a method for dismounting a crane and a jib that is easy to operate, stable and fast in disassembly, and a roof hanging device used in the disassembly method.

In order to achieve the above object, a roof hanging device of the present invention includes: a roof hanging base, a rotating mechanism, a swing bracket, a boom, a lifting mechanism, a pull arm mechanism, a diagonal brace and a support rod, and the roof hanging base is fixed on the roof Above, the rotating mechanism is fixed on the roof hanging base, one end of the revolving bracket is fixed on the rotating mechanism, the bottom end of the boom is fixed on the fixed end of the revolving bracket and the rotating mechanism, and is close to the lifting mechanism, so Both the lifting mechanism and the pull arm mechanism are fixed on the revolving support, the support rod is fixedly connected with the pull arm mechanism and is perpendicular to the revolving support, the top of the support rod is provided with a first fixed pulley, and one end of the diagonal brace It is fixed on the fixed seat at the hoisting mechanism, and the other end leans against the top of the support bar and extends out, and the first fixed pulley is arranged on the extension section, and the first steel wire rope goes around the first fixed pulley and the first fixed pulley on the top of the boom. The two fixed pulleys are connected and drive the boom to rise and fall. The lifting mechanism is wound with a second wire rope, and the second wire rope bypasses the third fixed pulley and passes through the fourth fixed pulley at the middle of the boom and the crane. The fifth fixed pulley on the arm is connected with the hook for hoisting the heavy object, and the base steel beam is arranged on the roof suspension base, and the base steel beam is fixed by fastening bolts penetrating the girder plate of the roof.

Wherein, the lower end of the foundation steel beam and the lower end of the beam slab of the roof are respectively provided with a first pressure plate and a second pressure plate, and the two pressure plates are arranged in parallel and fixed by fastening bolts to clamp and fix the foundation steel beam and the roof beam slab.

Wherein, the rotating mechanism includes a rotating main body and a support arm, the rotating main body includes a rotating shaft and a fixed frame, the rotating main body is fixed on the fixed frame, one end of the supporting arm is hinged with the fixed frame, and the other end extends outward to connect with the swing bracket It is fixedly connected, and the fixed frame, the support arm and the swivel bracket form a triangular shape as a whole.

Wherein, the connecting end of the boom and the swing bracket, the diagonal brace, the support rod, the fixed frame, the support arm and the corresponding components are all fixed by hinges, and the tightness of the connection is adjusted by bolts.

Wherein, the fourth fixed pulley is fixed on the boom and is close to the position where the lower end of the boom is connected to the rotating mechanism to increase the moment.

The invention also discloses a method for disassembling the internal climbing crane and the boom, including:

The roof crane device described above is installed, the roof crane device is installed near the tower crane, and the boom is higher than the tower cap position of the tower crane;

A ground pulley is installed at the intersection between the tower crane and the roof, and the ground pulley is fixed on the standard crossbar where the tower crane contacts the roof through fastening bolts and splints, and one end of the lifting wire rope of the tower crane itself is fixed on the balance arm of the tower crane The sixth fixed pulley, the other end is connected to the end of the boom after bypassing the seventh fixed pulley and the ground pulley installed on the tower cap in turn;

The hook on the roof crane device hangs the boom through the wire rope, controls the lifting of the boom through the first wire rope on the roof crane device, and rotates the swing bracket through the rotating mechanism, so that the boom can be disassembled smoothly and placed on the roof ;

Hang the wire rope bound with the balance arm through the hook, and smoothly remove the balance arm and place it on the roof;

The counterweight, tower cap, slewing assembly, jacking frame assembly and standard section are bound by hooks, and the counterweight, tower cap, slewing assembly, jacking frame assembly and standard section are removed respectively;

Separately install a pole crane on the roof, and disassemble the roof crane device by setting the pole crane on the roof;

After manual disassembly of the pole crane, the indoor elevator is used to transport it to the ground.

Among them, the foundation steel beam of the roof suspension base is connected to the floor through fastening bolts, and every two fastening bolts form a group and penetrate the first beam plate of the roof. The first pressure plate and the second pressure plate located at the lower end of the first beam plate of the roof clamp and fix the foundation steel beam and the roof beam plate; the reinforced steel column is sandwiched between the first beam plate and the second beam plate of the roof, so that One end of the reinforced steel column withstands the second pressure plate, the other end withstands the footing steel plate, and the footing steel plate is fixed on the second beam plate.

Among them, before the disassembly of the tower crane, use the internal climbing system of the tower crane to lower the tower crane to the lowest position away from the roof, fix the tower crane firmly at the position of the climbing frame, move the roof crane device to rotate, and use the boom of the roof crane device to lift it away from the counterweight. A counterweight is reserved for balance. When disassembling the counterweight, it is required to hang out the counterweight vertically and smoothly.

Among them, the method of installing a single pole crane on the roof is to fix the four end points and the intersection of the cross steel beam through the embedded bolts on the roof, and each embedded bolt is equipped with a load-bearing plate at the lower end of the cross steel beam. Fix the pole hanging base on the four sides of the beam.

Among them, the removal method of the roof crane device is not only to lower the boom of the roof crane to the roof, but also to manually dismantle it. The boom of the roof crane removes the bulky roof crane device.

The beneficial effects of the present invention are:

Compared with the prior art, the present invention provides a roof hanging device. In order to better fix the roof hanging device, the present invention fixes the basic steel beam on the roof hanging base through fastening bolts penetrating the beam plate of the roof. In addition, a parallel pressure plate is set to clamp and fix the foundation steel beam and the beam slab to reduce the stability when the roof crane is loaded with gravity and make it move more smoothly. Install a ground pulley at the position where the contact crosses, and pass the hoisting wire rope installed on the tower crane itself through the ground pulley and the boom to keep the boom in balance, and under the traction of the hook on the roof crane, the , Quickly disassemble the boom. This method is especially suitable for the disassembly of the super-long boom. The jacking frame assembly and the standard section are disassembled sequentially, and the disassembly process is simple and smooth.

Description of drawings

Fig. 1 is the structural representation of roof hanging device of the present invention;

Fig. 2 is the installation sketch map of roof suspension base and roof of the present invention;

Fig. 3 is a schematic structural view of the roof crane dismounting boom of the present invention;

Figure 4 is a schematic diagram of the installation of the pulley of the present invention;

Fig. 5 is a schematic diagram of the connection between the pulley and the standard section of the present invention;

Fig. 6 is a schematic diagram of the structure of the tower cap dismantled by the roof crane of the present invention;

Fig. 7 is a schematic diagram of the structure of the pole crane for dismantling the roof of the present invention;

Fig. 8 is the fixing sketch map of this method picks up the rod hanger and roof.

detailed description

In order to express the present invention more clearly, the present invention will be further described below in conjunction with the accompanying drawings.

Please refer to Fig. 1-Fig. 2, a roof hanging device disclosed by the present invention includes: a roof hanging base 11, a rotating mechanism 12, a swing bracket 13, a boom 14, a lifting mechanism 15, a pulling arm mechanism 16, and a diagonal brace 17 And support bar 18, roof hanging base 11 is fixed on the roof, and rotating mechanism 12 is fixed on the roof hanging base 11, and one end of revolving support 13 is fixed on the rotating mechanism 12, and the bottom end of boom 14 is fixed on revolving support 13 and rotating One end of mechanism 12 is fixed, and close to hoisting mechanism 15, hoisting mechanism 15 and pulling arm mechanism 16 are all fixed on the revolving support 13, and support rod 18 is fixedly connected with pulling arm mechanism 16 and is perpendicular to revolving support 13, and support rod 18 The top is provided with a first fixed pulley 21, one end of the diagonal brace 17 is fixed on the fixed seat at the lifting mechanism 15, and the other end leans against and fixed on the top of the support rod 18, and extends out, and the extension section is provided with a second fixed pulley 22 , the first wire rope 51 bypasses the second fixed pulley 22 and is connected with the third fixed pulley 23 at the top of the boom, and drives the boom 14 to rise and fall. After bypassing the first fixed pulley 21, the fourth fixed pulley 24 at the middle of the boom and the fifth fixed pulley 25 on the boom are connected to the hook 19 for lifting heavy objects. The roof suspension base 11 is provided with The foundation steel beam 111, the foundation steel beam 111 is fixed by fastening bolts 4 penetrating the first beam plate 31 of the roof, every two fastening bolts 4 form a group, and penetrate the first beam plate 31 of the roof, the fastening bolts 4 Clamp and fix the foundation steel beam 111 and the first beam plate 31 of the roof by clamping the first pressure plate 31 on the foundation steel beam 111 and the second pressure plate 1112 located at the lower end of the first beam plate 31 of the roof; A reinforced steel column 33 is sandwiched between the first beam 31 and the second beam 32, one end of the reinforced steel column 33 withstands the second pressure plate 1112, the other end withstands the footing steel plate 34, and the footing steel plate 34 is fixed on the second On the beam slab 32, this structure allows the entire roof crane device to be better fixed to the roof, avoiding shaking when the roof crane device is carrying heavy objects, so that the roof crane device is more stable and safe during use. Sex is higher.

In this embodiment, the rotating mechanism 12 includes a rotating body 121 and a support arm 122, the rotating body 121 includes a rotating shaft 1211 and a fixed frame 1212, the rotating body 121 is fixed on the fixed frame 1212, and one end of the supporting arm 122 is hinged to the fixed frame 1212, The other end extends outwards and is fixedly connected with the swivel bracket 13, and the fixed bracket 1212, the support arm 122 and the swivel bracket 13 form a triangular shape as a whole, so as to better support and fix the swivel bracket 13, and the fixed bracket 1212, the support arm 122 and the revolving bracket 13 are connected to each other in a hinged manner, and each connection assembly is fixedly connected by bolts. Similarly, the lifting mechanism 15, the pull arm mechanism 16, the diagonal brace 17, the support rod 18, the boom 14 and the revolving bracket 13 The connection between them is also fixed by hinge, and when the connecting end of the boom 14 and the swing bracket 13 is hinged, the tightness of the hinge bolt should be adjusted so that the boom 14 can rotate around the hinge bolt to ensure that the entire The boom 14 can move up and down.

In this embodiment, the fourth fixed pulley 24 is fixed on the boom 14 and is close to the position where the lower end of the boom 14 is connected to the rotating mechanism 12 to increase the moment when the second wire rope 52 lifts a heavy object through the hook 19 .

In this embodiment, the disassembly process of the supernormal jib of the internal climbing tower crane and the entire tower crane through the above-mentioned roof crane device is as follows:

Install the roof crane device described above, the roof crane device is installed near the tower crane 6, and the boom 14 is higher than the tower cap 61 position of the tower crane 6;

Please refer to Fig. 3-Fig. 6, a ground pulley 7 is installed at the position where the tower crane 6 is in contact with the roof, and the ground pulley 7 is fixed on the cross bar 651 of the standard section 65 where the tower crane 6 contacts with the roof through fastening bolts 4 and splints 8 One end of the hoisting wire rope 66 of the tower crane 6 itself is fixed to the sixth fixed pulley 26 on the balance arm 63 of the tower crane 6, and the other end goes around the seventh fixed pulley 27 and the ground pulley 7 installed on the tower cap 61 successively. connected to the end of the boom 62;

The hook 19 on the roof hanging device 1 hangs the boom 62 through the steel wire rope, controls the lifting of the boom 14 through the first steel wire rope 51 on the roof hanging device 1, and rotates the swing bracket 13 through the rotating mechanism 12, thereby lifting the crane The arm 63 is smoothly disassembled and placed on the roof;

Hang the wire rope bound with the balance arm 63 through the hook 19, and smoothly disassemble the balance arm 63 and place it on the roof;

The counterweight 64, the tower cap 61, the rotary assembly 67, the jacking sleeve assembly 68 and the standard section 65 are bound by the hook 19, and the counterweight 64, the tower cap 61, the rotary assembly 67, the jacking Dismantling of sleeve frame assembly 68 and standard section 65;

Separately install a pole crane on the roof, and disassemble the roof crane device by setting the pole crane on the roof;

After manual disassembly of the pole crane, the indoor elevator is used to transport it to the ground.

In this embodiment, before the disassembly of the tower crane 6, use the internal climbing system of the tower crane 6 to lower the tower crane 6 to the lowest position away from the roof, fix the tower crane firmly at the position of the climbing frame, move the roof crane 1 to rotate, and use the boom of the roof crane 1 14 Hoist 4 pieces of counterweight, and leave a piece of counterweight for balance. Install two "herringbone"-shaped poles on the lower pole of the second section of the front section of lifting 62 (not shown in the figure), and use a 5T chain block to control the handle. The overturning of pole hanger is to reach the effect of controlling suspension hook 19 central points. Use the tower crane 6 to lift the steel wire rope 66 as the traction power to lift the 7th boom 62 to be stressed, then knock off the connecting pin of the boom 62, and loosen the 5T chain hoist slightly to make the 7th boom There is a distance between the boom and the boom section 6, and then start the main lifting mechanism (not shown in the figure) to hoist the boom 62 to the ground. Use this method to remove the boom section 5 in sequence and use the roof crane device 1 The 50-meter boom 62 front end of the tower crane 6 is hoisted at an angle of 15 degrees to make the front tie rod bend, and the roof crane device uses the hook 19 to lift the 40-meter boom 62 to the roof at one time.

In this embodiment, the steps for removing the balance arm 63 are:

a. Use the roof hanging device 1 to hang the remaining balance weight;

b. Through the installation lugs (not shown) on the balance arm 63, use the roof crane device 1 to lift the balance arm 63, so that the balance arm 63 pull rod is in a state of no force, and remove the connecting pin in the middle of the balance arm 63 pull rod;

c. Balance arm 63 is hoisted, put on the support that the ground is cushioned with sleepers.

In this embodiment, the steps for disassembling the balance arm 63 are:

a. Fix the rope on the lug at the top of the tower cap, and slowly tighten the rope;

b. Disassemble the connecting pin with the

c. Lift the tower cap and put it on the support with sleepers on the ground.

Check whether there is a cable connection between the adjacent parts. There is a safety piece on the tower cap. Pay attention to protection during the hoisting process. When placing it on the ground, be careful not to press the safety piece. During the hoisting process, be careful not to let the tower cap swing during the movement. The amplitude is too large to avoid collision with other components.

In this embodiment, the way to disassemble the slewing assembly is as follows: the slewing assembly includes an upper support, a lower support, a slewing support and a cab;

a. Remove the eight M30×360-10.9 high-strength bolts connecting the lower support to the standard section;

b. Fix the rope on the upper support, slowly tighten the rope, and remove the 4 connecting pins between the lower support and the climbing frame;

c. The slewing assembly 67 is hoisted and placed on the support on which the ground is cushioned with sleepers.

Therefore, in the present embodiment, the removal of the rotary assembly 67 is to pay attention to destroying the tower crane 6 parts. There are many electrical components on the rotary assembly 67, and attention should be paid to protection. During the disassembly process, attention should be paid to protecting vulnerable parts such as the driver's cab.

Therefore, in this embodiment, the way to disassemble the jacking sleeve assembly is:

Fix the ropes on the four chords at the top of the jacking frame, use the roof crane device 1 to lift it out from the standard section of the tower crane, place it on the support with sleepers on the ground, and lift it out completely when the jacking frame is fully lifted. When erecting the tower body, the jacking frame cannot be pulled obliquely.

The way to remove the remaining standard sections is: fix the steel wire rope on the standard section, remove the remaining standard sections with the hook 19, and disassemble the foundation section and ground pulley 7 and other components.

Figures 7-8, the last is the disassembly of the roof hanging device 1. The removal method of the roof hanging device 1 is to lower the boom 14 of the roof hanging device to the roof and disassemble it manually. When the roof hanging device 1 used is large , by installing a small-volume roof-hanging device near the roof-hanging device, use the arm of the small-volume roofing crane to remove the large-volume roof-hanging device[K1].

When the roof hanger 1 is manually disassembled, a pole crane 90 is usually required as an auxiliary mechanism for disassembly. The pole crane 90 is usually installed near the roof hanger 1. The specific installation method is as shown in the figure. The four ends of the beam 91 and the crossing parts are fixed by the embedded bolts 92 on the roof, and the lower end of each embedded bolt 92 is provided with a load-bearing plate 93, and it is enough to fix the pole hanging base 90 on the four sides of the cross steel beam 91 The roof crane 1 is disassembled by connecting the fixed pulley on the pole crane with the steel wire rope and the luffing trolley. After the roof crane 1 is disassembled, the pole crane 90 is manually disassembled and transported to the ground by an indoor elevator.

The advantages of the present invention are:

1) In the present invention, the foundation steel beam on the roof suspension base is fixed by fastening bolts penetrating the beam plate of the roof, and a parallel pressure plate is provided to clamp and fix the foundation steel beam and the beam plate, so as to reduce the load on the roof suspension The stability when there is gravity makes it move more smoothly;

2) And using this roof crane device, install a ground pulley at the contact crossing position between the tower crane and the roof, pass the hoisting wire rope installed on the tower crane itself through the ground pulley and the boom to keep the boom Balanced, and under the traction of the hook on the roof crane, the boom can be dismantled smoothly and quickly. This method is especially suitable for the disassembly of super long booms;

3) After the lifting arm is disassembled, use the roof crane device to disassemble the balance arm, counterweight, tower cap, slewing assembly, jacking frame assembly and standard section of the tower crane in sequence. The disassembly process is simple and smooth .

The above disclosures are only a few specific embodiments of the present invention, but the present invention is not limited thereto, and any changes conceivable by those skilled in the art shall fall within the protection scope of the present invention.

Claims (10)

1. a roofing device for hoisting, it is characterised in that including: roofing hangs base, rotating mechanism, convolution support, arm, lifting machine Structure, torque arm mechanism, diagonal brace and support bar, described roofing hangs base and is fixed on roof, and described rotating mechanism is fixed on roofing and hangs On base, one end of described convolution support is fixed on rotating mechanism, and the bottom of described arm is fixed on convolution support and rotation One end that mechanism is fixing, and near lifting mechanism, described lifting mechanism and torque arm mechanism are each attached to circle round on support, described Strut is fixing with torque arm mechanism to be connected and is perpendicular to described convolution support, and described supporting bar top is provided with the first fixed pulley, institute Stating diagonal brace one end to be fixed on the fixing seat at lifting mechanism, the other end leans on the top being fixed on support bar, and extends, and Its extension arranges the first fixed pulley, and the first steel wire rope is walked around the first fixed pulley and is connected with second fixed pulley on arm top, and Driving arm rise and fall, described lifting mechanism is wound with the second steel wire rope, it is fixed sliding that described second steel wire rope walks around again the 3rd After wheel by after the 5th fixed pulley on the 4th fixed pulley of arm medium position and arm with the suspension hook for weight of slinging even Connecing, described roofing hangs and is provided with basis girder steel on base, and described basis girder steel is solid by the fastening bolt penetrating the beam slab on roof Fixed.

Roofing device for hoisting the most according to claim 1, it is characterised in that described girder steel lower end, basis and the beam slab on roof Lower end is respectively arranged with the first pressing plate and the second pressing plate, and two block pressur plates are be arranged in parallel and fixed by fastening bolt and by basis steel Beam grips with the beam slab on roof.

Roofing device for hoisting the most according to claim 1, it is characterised in that described rotating mechanism includes rotating main body and support Arm, described rotation main body includes that rotating shaft and fixed mount, described rotation main body are fixed on fixed mount, and one end of support arm is with fixing Frame is hinged, and the other end stretches out be connected fixing with convolution support, and fixed mount, support arm enclose one with convolution support entirety Individual triangular shaped.

4. according to the roofing device for hoisting described in claim 1 or 3 any one, it is characterised in that described arm and convolution support The connection connecting end, diagonal brace, support bar and fixed mount and support arm and each corresponding this part of assembly be all by hinged Mode is fixed, the elasticity connected by bolt regulation.

Roofing device for hoisting the most according to claim 1, it is characterised in that described 4th fixed pulley is fixed on arm, and The position being connected with rotating mechanism near arm lower end is to increase moment.

6. an inner climbing type crane and the method for dismounting of crane arm, it is characterised in that including:

Being provided with the roofing device for hoisting described in the claims 1-5 any one, it is attached that described roofing device for hoisting is arranged on tower crane Closely, and arm is higher than the tower cap position of tower crane；

Tower crane contacts the position intersected and is provided with a lower sheave with roof, and described lower sheave passes through fastening bolt and Boards wall On the standard knot cross bar that tower crane contacts with roof, one end of the hoist rope of tower crane self is fixed on tower crane counter-jib 6th fixed pulley, the end that the other end is walked around the 7th fixed pulley being arranged on tower cap successively, is connected to crane arm after lower sheave End；

Suspension hook on roofing device for hoisting tangles crane arm by steel wire rope, controls to hang by the first steel wire rope on roofing device for hoisting The lifting of arm, by rotating mechanism, rotates back to circumflex branch frame, thus is steadily dismantled by crane arm and be placed on roof；

Tangled the steel wire rope being bundled with counter-jib by suspension hook, smoothly counter-jib dismantled and be placed on roof；

Tangled by suspension hook and be bundled with counterweight, tower cap, rotating assembly, jacking stock assembly and standard knot, respectively by counterweight, tower Cap, rotating assembly, jacking stock assembly and standard knot dismounting；

One gin-pole truck is set on roof the most again, by arranging gin-pole truck dismounting roofing device for hoisting device on roof；

Indoor elevator is utilized to be transported to ground after gin-pole truck artificial unloading.

A kind of inner climbing type crane the most according to claim 6 and the method for dismounting of crane arm, it is characterised in that roofing hangs The basic girder steel of base is connected with flooring by fastening bolt, and each two fastening bolt becomes one group, and penetrates first beam on roof Plate, the first pressing plate that fastening bolt group is positioned on the girder steel of basis by clamping is pressed with the second of the first beam slab lower end being positioned at roof The beam slab of basis girder steel with roof is gripped by plate；It is clamped with reinforcing steel column between first beam slab and second beam slab on roof, The second pressing plate is withstood in one end of described reinforcing steel column, and the other end withstands feet steel plate, and by feet Interal fixation at the second beam slab On.

A kind of inner climbing type crane the most according to claim 6 and the method for dismounting of crane arm, it is characterised in that tower crane is torn open First with system of climbing in tower crane itself, tower crane is down to from roofing extreme lower position, in frame position of climbing by tower crane fix tightly before unloading Leaning on, mobile roof device for hoisting turns round, and utilizes the arm of roofing device for hoisting to hang counterweight, but one piece of counterweight need to be stayed to make balanced action, During dismounting counterweight, it is desirable to vertically smoothly hang out counterweight.

A kind of inner climbing type crane the most according to claim 6 and the method for dismounting of crane arm, it is characterised in that on roof The mode of a separately installed gin-pole truck is, four end points and the crossover sites of cross girder steel are passed through the pre-buried spiral shell on roof Bolt is fixed, and each pre-embedded bolt lower end is both provided with bearing plate, fixes gin-pole truck base on four limits of cross girder steel.

A kind of inner climbing type crane the most according to claim 6 and the method for dismounting of crane arm, it is characterised in that roofing The method for dismounting of device for hoisting is lowered into roof except the arm hung by roofing, outside artificial unloading, when the roofing used hangs bigger Time, hanging by installing the roofing of a small size at roofing near hanging again, the arm hung with small size roofing removes large volume Roofing device for hoisting.