AU627502B2

AU627502B2 - Improvements in crane towers

Info

Publication number: AU627502B2
Application number: AU42403/89A
Authority: AU
Inventors: Boris Lapcevic
Original assignee: BORMIL CORP Pty Ltd
Current assignee: Lapcevic Boris
Priority date: 1988-09-30
Filing date: 1989-09-28
Publication date: 1992-08-27
Anticipated expiration: 2009-09-28
Also published as: AU4240389A

Description

r ta LII PATF ACT 1952 COMPLETE SPECIFICATION

(ORIGINAL)

FOR OFFICE USE Form Short Title: Int. CI: Application Number: PJ 0732 Lodged: 30th. September 1988 0 CdrilrFete Specification-Lodged: 29th. September 1989 Accepted: I Lapsed: Published: Priority: R.litded Art: 4 t tt I t r TO BE COMPLETED BY APPLICANT Name of Applicant: Bormil Corporation Pty. Limited I ft Address of Applicant: 9 Perry Street, Matraville, New South Wales 2026.

Actual Inventor: Milos Lapcevic of 27 Beaumont Street, Rose Bay, New South Wales.

Address for Service: H.J. Rantzen Co., Patent and Trade Mark Attorneys.

John Street, Woollahra, N.S.W. 2025.

Tel: (02) 328-7560.

Complete Specification for the invention entitled: IMPROVEMENTS IN CRANE TOWERS The following statement is a full description of this invention, including the best method of performing it known to me:- S Note: The description is to be typed ir double spacing, pica type face, in an area not exceeding 250 mm in depth and 160 mm in width, nn tough white paper of good quality and it is to be inserted inside this form.

14166/77-L Printed by C. J. THoMlPsoN, Acting Coimmonwealth Government Printer, Canberra

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i' i -C THIS INVENTION relates to tower cranes used on building sites where multi-storey buildings are being erected. More specifically, it is concerned with a construction of tower used to support the arm or jib of a tower crane.

It is common practice to increase the height of a tower crane during the construction of a multi-storey building. The tower of the crane may be laterally supported by the building while it is being built, and the unsupported length of the tower above the building is restricted to that which is essential, so that the loads carried by the crane l'o. can be relatively large, and the likelihood of the tower toppling is minimised.

The tower is formed by identical tower sections bolted to one another.

0 0 "To increase the height of the tower, it is necessary to add sections.

This is normally done at night when the crane is not in use. Various rooo techniques are used to add a tower section to an existing tower, and jacks are required. The job is both highly-skilled and dangerous.

The sections from which the tower is constructed ar fabricated by welding at a workshop. They are then taken by road to the site of use. Great care is necessary in fabricating the sections and they o U.

often have to be transported long distances to the construction site. Because of the size of the sections, usually not more than three can be transported in one load. Several journeys are therefore necessary to transport a tower crane structure to a site of use.

SThese journeys are repeated to transport the crane from the site when the building erection is finished. This is one of the many cost factors built into the cost of hiring a tower crane and which makes it an expensive although essential item.

An object of this invention is to provide an improved tower crane.

-2- I i In accordance with the present invention a tower for a tower crane comprises a column of box-sections of rectangular or square cross-section g e attached to one another at their ends and Cm- n be!c, A 4 rYe. I first pair of opposite sides I of welded construction and za second pair of opposite sides) constructed from rigid members detachably bolted bolted to the first pair of sides.

9* 9A 9 99/lW 9 r S t* a d9 9 90 9 9O A box-section of a tower crane constructed as set forth in the invention has the advantage that it can be transported to site in a 'knocked-down' and therefore compact condition which enables more box-sections in knocked-down form to be transported to site in a single load than is possible with the all-welded box-sections of the conventional crane tower. A second advantage is that the insertion of a box-section into a tower to raise the height of the crane, can be done with less risk as the maximum load which has to be moved into position at any one time is the weight of one welded side of the box-section. A further advantage is that a footplate provided around a foot of the crane cab can be larger than has hitherto been possible, as it can be placed in position in its box-section as a stage in the assembly of the box-section during its incorporation into the tower of the crane.

The invention will now be described in more detail, by way of example, with reference to the accompanying partly diagrammatic and informal drawings, in which:- FIGURE 1 is a plan view of a box-section of a crane tower located immediately beneath a driving cab (not shown); FIGURE 2 is a cross-section through the box-section of figure 1, taken on the line and in the direction indicated by the arrows A-A in figure 4; FIGURE 3 shows the box-section of figure 1 in side elevation to show a side of the box frame which is constructed from bolted-together, rigid members; -3r

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FIGURE 4 shows, in elevation, the box section of figure 1 as viewed from the back to illustrate one of an opposed pair of side frames fabricated from welded-together beams; and, FIGURE 5 is a plan view of structure providing a reticulated platform mountable inside the box-section during its assemby.

The tower crane is constructed from box sections erected one above the other and bolted together at their ends in conventional manner.

99 9, To increase the height of the tower a team of skilled constructors, °oI operating usually at night, jacks up the crane together with the operator's cabin and the top box section, and inserts a new box a section immediately beneath. The jacked-up parts of the crane are 000then lowered onto the newly-inserted box section which is re-bolted *p into position.

The box section shown in the figures is the top box section which 0.*a is jacked up with the crane when the tower height is to be increased. C. 0 0 0. It is therefore shown with an internal platform giving the crane 0.

operator access to his cabin. The assembly of the top box section is similar to that of the box sections on which it rests, apart from Sthe positioning of the platform within it. The method of assembly of the top box section is described beneath and where there are differences between its assemby and the assembly of the other box sections, only the differences will be explained. The assembly of slightly different box sections located beneath the illustrated box section is not therefore being separately described, to avoid unnecessary repetition of description.

The box section illustrated has two pairs of opposed sides. One pair is constructed as a generally flat welded panel prefabricated in a factory, and the other pair is constructed from beams bolted together in situ on the crane tower whose height is being increased.

As all the components from which the box section is constructed

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are substantially flat, they are readily transported to the site of use. Also, as the individual components are much lighter than the assembled box section, the assembly of the box section in situ on the crane tower from parts lifted into place, can be more easily carried out.

Referring to figure 1 the assembled box section shown in plan has one pair of opposed sides I each formed, as shown in fi gure 4, as a generally flat panel of welded together beams 6,7 and 8. The other pair of opposite sides 2 each has the shape shown in figure 3 and is constructed from members 3 bolted at their ends to plates 17 attached to the sides 1.

0 0 As shown in figure 1, the two horizontal beams 3 of the sides 2 have two divergent legs 10 welded to their centres to give the beams 3 a generally shape. The free ends of the legs 10 are bolted to plates 11 welded to the centres of the horizontal beams 7. Each of the K-beams 3 has a drilled web 18 at the centre of its back.

A ladder 12 is bolted by stays 13 to one pair of adjacent ends Sof the K-beam 3. Except for the uppermost box section of the tower, each of the box sections has its ladder 12 extending the full height of the box section and aligned with the corresponding o ladders 12 of the box sections beneath. The crane operator can therefore climb up the ladders 12 to the crane cab (not shown) supported on the uppermost box section.

Drilled pads 14 at the top and bottom corners of the box sections allow them to be bolted together, one above the other.

The description, thus far, is common to all of the box sections of .the tower. All but the uppermost box section are assembled as follows.

The uppermost box section containing the crane driver's cab (not shown) and supporting the arm or jib of the crane, has its lower I I e pads 14 unbolted from the top of the box section immediately beneath, and is jacked up by means (not shown) sufficiently to enable a new box section to be assembled immediately beneath. This is done by first lifting into position each of the sides 1 shown in figures 1 and 4, one at a time. Their lower pads 14 are bolted to the pads on the top of the box section immediately beneath.

The sides 2 are next assembled. The lower pair of diagonal beams 3, shown in figure 3, are first lifted and bolted at their lower ends to the plates 17. The lower K-beams 3 are next individually lifted into position and are arranged as shown in figure 1 prior to being bolted to the plates 17 and 11. the upper ends of the lower pair 9 4 of diagonal beams 3 are then bolted to the webs 18 at the centres of the backs of the K-beams 3. The upper pair of diagonal beams S3 is next raised and bolted into the positions shown in figure 3.

15 Finally the upper pair of K-beams 3 are individually lifted and bolted 4 to the upper plates 17 and 11. The upper end of the upper diagonal beams 3 are bolted to the webs 18. The ladder 12 can then be bolted to the position shown in figure 1.

The assembly of the uppermost box section is slightly different from that just described, as it incorporates a platform to enable the crane driver to transfer safely from the ladder 12 to the crane cab. The platform, referenced 30 and shown in detail in figure spans across the centre of the box section which is provided with a handrail 31 extending around its interior about a metre above -25. the platform 30. A second ladder 33 extends t:pwards from the platform 30 to the top of the box section, on its side opposite to the ladder 12 which is foreshortened so as to terminate at its i upper end slightly above the level of the handrail 31, as shown in figure 3. The lower end-portion of the ladder 12 is secured by being bolted between the ends of opposed stays 35 respectively welded to the lower pair of diagonal beams 8 of the side 1, as shown in figure 4.

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The platform 30 comprises a steel mesh grid shown in figure It has four tabs 36 and a rebate 37 which allows the crane operator to ascend through it when climbing up the ladder 12 to get onto the platform The platform 30 is prefabricated at a factory and integrally formed with two K-beams 3 as shown in figure 5. It is transported to the site of crane erection with the other parts of the box section. The metal mesh of the platofrm 30 is welded to the undersides of the K-beams 3 so that a rigid plat form structure results. At the site of crane assembly, the platform structure is lifted into position as a single unit during assembly of the uppermost box section, after the sides 1 and the lower pair of diagonal beams 3 have been bolted into position. The K-beams supporting the platform 30 are bolted o, O. into position and the remaining parts of the sides 2 are bolted into place as has previously been described. Finally the short ladder 33 is bolted into place to complete the assembly of the uppermost box section.

As the uppermost box section is raised with the crane during increase in height of the supporting tower, it never has to be disassembled S"020 until the crane is no longer required.

0 a 0 *From the above description it will be understood that the box sections of the crane tower can be transported in a knocked-down flat condition 0 so that fewer journeys are necessary to transport the crane tower to its site of use. Also, during assembly, the maximum weight 5 which has to be hauled to the top of the tower to increase its height, is the weight of one side 1 only. This is a much lighter weight than the weight of an entire box section which, formerly, had to be hauled up the tower when its height was to be increased.

-7i 7 !i It will be understood from the above description that the invention in its broadest form covers not only a tower for a tower crane, but also a box section for a tower of a crane and provided from substantially two-dimensional components of which two respectively provide panels which form the first pair of opposite sides of the section, and the remaining components comprise beams for bolting between the first pair of sides to form the second pair of sides.

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Claims

1. A tower for a tower crane ar. comprising a column of box sections of rectangular or square cross-sections attached to c7rs-k; c-c wcA pSecnd pc(5 ok oose Sic2e'S^-te- one another at their ends, and c aving 1a first pair of opposite sidesAof welded construction, and a second pair of opposite sidesA constructed from rigid members detachably bolted to the first pair of sides. 0o 0

2. A tower as claimed in Claim 1, in which each of the second pair of opposite sides includes two K-beams arranged .i ht and having the end-portions of the divergent limbs of the extending towards one another and bolted to ,o central zones of the first pair of opposite sides.

3. A tower crane as claimed in Claim 2, provided with a ladder composed of a line vertical sections each of which is located in a box section of the tower and is provided at the central zone of one side of the first pair of opposite sides. 0@ 0 I

4. A tower as claimed in Claim 2 or Claim 3, in which a platform is integrally assembled with one pair of opposed K- .e beams in the uppermost box section of the tower. o 00 A tower as claimed in Claim 4, in which the platform comprises a grating attached to the underside of the two opposed K-beams, and a rebate in the platform is arranged around the upper end of a lower ladder section in the uppermost box-section, and an upper ladder section is provided above the level of the platform in the upper portion of the uppermost box-section at a position opposite the rebate.

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6. A box section for a tower as claimed in any one of the preceding claims, provided from substantially two- dimensional components of which two respectively provide panels which form the first pair of opposite sides of the section, and the remaining components comprise beams for bolting between the first pair of sides to form the second pair of sides.

7. A box section as claimed in Claim 6, in which two of the beams comprise opposed, co-planer K-beams to which is attached a platform having a rebate disposed adjacent the junction of two divergent limbs of respective K-beams. o

8. A tower for a tower crane as claimed in Claim 1, and 94 formed from box-sections each constructed substantially as S described with reference to the accompanying drawings.

9. A box section as claimed in Claim 6, formed from components substantially as described with reference to the accompanying drawings. o a o 0 DATED THIS A 5 DAY OF SEPTEMBER 1989. BORMIL CORPORATION PTY LTD Applicants Patent Attorney