RU2091549C1 - Method of mounting of tower and mast structures by means of crank mechanism - Google Patents

Abstract

FIELD: mounting of building structures; methods of mounting of tower and mast structures by building-up with large space sections by means of crank mechanism. SUBSTANCE: two tackle blocks 5 with one common rope are secured from outer sides to lower part of structure 4 mounted by one of traditional methods (by crane or mast). Enlarged on ground surface is rigid block consisting of several space sections C1, C2, C3, C4 which are rigidly connected to one another by one face with two flat hinges 6, and by the opposite face, with temporary bolts. Block is lifted in vertical position by means of tackle blocks and guy, and its upper end is secured to upper part of structure 4 mounted before by means of two hinges 7. Lower movable roller of tackle blocks 5 are connected with bottom of hanging vertical blocks. Temporary bolts are removed between two upper sections C1 and C2 with hinges 6 remaining intact. Block is turned in this way into crank mechanism in which upper block C1 is crank and rigid block consisting of sections C2, C3, C4 serves as connecting rod. After switching-on electric hoist of tackle blocks 5 for lifting bottom of section C4 (slider) slides over temporary guides 10 to rise, and section C1 - crank, after turning through 180 deg and fastening, assumes design position, connecting rod hangs on hinges 6, and after removal of temporary bolts between two upper sections of connecting rod turns into a new crank mechanism in initial position for starting next cycle. In this way, all sections of initially suspended block (C1, C2, C3) is successively turned into crank, then, in stem of structure. In this case, the last section (C4) is mounted with the help of false section 8 used as the last connecting rod. Sections of block in mounting are transformed into stem of structure due to the fact that enlarged block consists of sections interconnected for time of mounting by one face with hinges 6. EFFECT: higher efficiency. 3 dwg

Description

 The invention relates to the field of installation of building structures.

 Currently, there are three known methods of mounting tower and mast structures: a) the method of building, when structures are mounted from bottom to top by individual elements of the structure or sections enlarged on the ground; b) the method of growing when mounted from top to bottom, i.e. first they mount the base and the upper part of the structure, lift it to a certain height and connect the underlying part to it from below, then again lift up the entire previously mounted part, etc. c) by the method of rotation around the hinge, when the entire structure is assembled on the ground in a horizontal position and completely raised by turning around the hinges attached to the base of the structure and to the foundation.

When installing structures by building using known methods:
using self-propelled jib cranes or masts;
using special cranes installed on a pre-mounted part of the structure (suspended, self-lifting, creeping)
with the help of masts installed on the mounted part of the structure;
using special portals installed on the installed part of the structure;
using helicopters.

 The installation method of long structures is the closest analogue (prototype) to the invention.

 The essence of this method [1] is as follows. The design of the tower (mast) using an assembly crane is collected on the ground in a horizontal position from two blocks interconnected by hinges along the lower edge. The first spatial block is longer than the second one by hinges connected to the foundation. The second block consists of several spatial sections. The sections are connected at an angle to each other along the lower edge by hinges and rigidly fixed on the opposite side. Thus, the assembled structure has an initial deflection arrow at the joints with hinges. With the help of chain blocks connecting the free end of the second block and the hinges on the foundations, the end of the second block (slides along the ground) is brought together with the hinge of the foundation, while the first block rotates around the hinges of the foundation until the second block, performing a translational-rotational movement, is established in vertical position.

 Then the movable pulley pulleys are fixed to the upper end of the first block, and the fixed pulley pulleys to the anchor outside the foundation (the farther from the foundation the better) and the first block around the hinges on the foundation is pulled to the vertical position with the help of pulley blocks, while the second block hangs on the hinges connecting the first block with the second.

 The second block in the design position is installed sequentially using a crank mechanism with preliminary unlocking.

 The proposed method using the installation of the crank mechanism is as follows.

 The lower part of the structure is mounted using a self-propelled jib crane to a height allowed by the crane's capabilities (lifting height, lifting capacity, reach). To the upper part, from the outer sides, two pulley blocks are fixed 5 whose ends are connected to winches mounted on the ground.

 The rest of the structure is collected on the ground in a rigid block, the length of which is less than or equal to the height of the previously mounted part. The block consists of several spatial enlarged sections C1, C2, C3, C4 (Fig. 1).

 The joints of the sections belts are connected on one side by two flat hinges 6, on the other, on the opposite side (or on the edge if the cross-section is trihedral) with temporary bolts. With the help of pulley 5 and a guy, the block (C1, C2, C3, C4) is lifted up.

 The upper end of the block is fixed with two hinges 7 (Fig. 1) to the top of the mounted part of the structure 4. The block hangs on the hinges 7. Connect the pulley pulleys to the lower end of the hanging block, remove the temporary bolts at the junction of sections C1 and C2 (the hinges remain). The suspended unit turns into a crank mechanism.

Including the hoist winch 5 on the "rise", section C1 is rotated around the hinges 7 by 180 ^o , and the bottom slides along the guides and fixed to the previously mounted part 4. Remove the temporary bolts along the outer edge at the junction of sections C2 and C3 and the cycle repeats again.

 The initial deflection arrow between the connecting rod and crank is created by the positive difference between the ratios of the torques relative to the joints from the dead weight of the connecting rod and crank to their lengths. If the difference is negative, then to create the initial arrow of deflection along the outer edge at the joints of the sections, the mass of the next section (block) C5 pivotally suspended along the outer edge is used as an additional load. The last section is raised using a false section.

If the force in the tackle Q _{floor is} sufficient, i.e.

кривошип и шатун будут совершать поступательно-вращательное движение под действием только усилия в полиспастах и моментов от собственного веса относительно шарниров по концам шатуна и кривошипа.Q _floor > P ₁ + P ₂ + P ₃ + P ₄ + N _w f _tr + P ₅ (Fig. 2)
where f _{Tr the} coefficient of friction of sliding the lower part along the guide

the crank and connecting rod will perform translational-rotational movement under the action of only efforts in the chain hoists and moments of its own weight relative to the hinges at the ends of the connecting rod and crank.

The prototype and the proposed method have common features:
part of the structure is mounted using a crank mechanism;
the enlargement of blocks (sections) is carried out using an assembly jib crane.

Features:
1. According to the prototype, the structure is assembled on the ground entirely from two blocks connected by a hinge and raised from a horizontal position by pulling together the ends of the blocks with the help of chain hoists. In our opinion, high towers and masts are so impractical to raise. It is known that towers and masts are up to 400 m or more high.

 For example, TV towers with a height of H 200 m have a mass of 250 to 500 tons. The force in the pulley block depends on the initial arrow of the deflection.

When the arrow deflection f _article 0 the force in the chain hoist will be equal to ∞ infinity.

with an arrow f _st 3 m, the force in the chain hoist will be more than 1000 tf.

with an arrow f _st 10 m, the force in the chain hoist will be more than 300 tf.

 To create such an arrow, powerful cranes are needed, or an entire overpass on which the structure will be assembled (Fig. 3).

При таких усилиях таким способом можно поднять башню (мачту) больших размеров, но традиционными способами проще и дешевле. Подъем сооружений таких размеров и такой массы требуют предварительного усиления элементов, так сечения мачт очень малы по сравнению с высотой (длиной).

With such efforts, in this way you can raise a tower (mast) of large size, but traditional methods are simpler and cheaper. The rise of structures of such sizes and such masses requires preliminary reinforcement of the elements, so the mast sections are very small compared to the height (length).

 The proposed method, the installation does not depend on the size of the structure and the total mass, since the first block is mounted using a jib crane, and the rest are separate blocks of several sections each.

 2. To assemble the structure on the ground according to the prototype, significant areas are required (towers and masts reach a height of 400 m or more), which is not always possible in the conditions of development in the mountains, and the proposed method requires a minimum area.

 3. According to the prototype for installation by a crank method, there are no guides so as not to cling to the lattice of the mounted part, therefore, additional measures are necessary (pulley bevel, etc.) which are not reported in the description.

4. prototype penultimate section when mounting the latter section should be longer than the amount of minimum length pulley otherwise tighten on 180 ^o.

 5. The proposed method expands the possibility of application for the installation of structures of any height and any mass at minimal cost.

 The proposed method is illustrated in FIG. 1 and 2.

In FIG. 1 are shown:
1 crank section C-1;
2 connecting rod, consists of section C2, C3, C4;
3 slider;
4 rack, previously mounted part of the structure;
5 mounting pulley;
6 movable hinges;
7 fixed hinges;
8 false section;
9 tap-off unit;
10 temporary guide;
In FIG. 2 scheme of efforts in the elements of the crank mechanism.

P ₁ crank weight (sections C1);
P ₂ weight of the upper section of the connecting rod C2;
P ₃ weight of the middle section of the connecting rod C3;
P ₄ weight of the lower section of the connecting rod C4;
l _cr shoulder of the moment of force P ₁ relative to the hinge connecting the crank and connecting rod;
l ₁ , l ₂ , l ₃ shoulders of moments, respectively, from forces P ₁ , P ₂ , P ₃ relative to the slider;
N _{w the} force in the hinge (reaction) and the slider from the moment of own weight of the connecting rod relative to the slider;
N _{cr the} force in the hinges (reaction) of the crank from the moment of its own weight relative to the movable hinge;
L _cr , L _{W the} height of the crank and connecting rod, respectively;
Q _n force in the chain hoists.

Claims (1)

The method of mounting tower mast structures by building reinforced spatial sections using a crank mechanism, in which the previously mounted part of the structure is used as a rack, the mounted sections are used as a crank, rotated 180 ^o and attached to the previously mounted part of the structure, and as a connecting rod use a block pivotally connected to the stand and consisting of several sections pivotally connected to each other with the possibility of fixing and unlocking characterized in that the initial installation of the rack is carried out using an assembly jib crane, and as the slider, the lower part of the block is used, sliding along temporary guides under the action of pulley blocks, the movable rollers of which are attached to the lower part of the block, the last section being installed using a connecting rod of a false section, the length and mass of which is greater than the length and mass of the last section.

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