US3909863A

US3909863A - Bridge crane girder

Info

Publication number: US3909863A
Application number: US389357A
Authority: US
Inventors: Karl Macrander; Heinrich Kessel
Original assignee: Fried Krupp AG
Current assignee: VULKAN HAFENTECHNIK GmbH
Priority date: 1972-09-11
Filing date: 1973-08-17
Publication date: 1975-10-07
Anticipated expiration: 1992-10-07
Also published as: JPS4964149A; DE2244566A1; DE2244566B2

Abstract

A bridge crane girder of the box structure type, which has an upper cord and a lower cord, and in which at least the lower cord is relieved by preloaded cables.

Description

United States Patent 1 1 1111 3,909,863

Macrander et a1. 1 Get. 7, 1975 [54] BRIDGE CRANE GIRDER 14,314 2/1856 435,155 55/1890 [75] Inventors: Karl Macrander; Heinrich Kessel, 530 425 12/1894 both of Wilhelmshaven, Germany 2 5 4 1 10/195 [73] Assignee: Fried. Krupp Gesellschaft mit 2'936907 5/1960 beschrankter Haftun German 3003217 10/1961 y 3,010,257 11/1961 [22] Filed: Aug. 17, 1973 3,084,909 4/1963 3,202,394 23/1965 [21] Appl. No.: 389,357 3,283,457 11/1966 3,427,773 2/1969 3 8 1 k 52 225 X [30] Foreign Application Priority Data 371 2/ 972 L15 a Sept. 11, 1972 Germany 2244566 Primary Examiner Nile C. y Jr 52 us. c1. 14/17; 52/226; 212/19 Attomey Agem Fm'hwaflter Becker [51] Int. Cl. 1304C 3/02 [58] Field of Search 14/10, 17, 11; 212/10, 57 R C A brlclge crane g1rder of the box structure type, wh1ch [56] References Cited has an upper cord and a lower cord, and in which at UNITED STATES PATENTS least the lower cord 1s rehevecl by preloaded cables.

13,461 8/1855 Hervey et a1. 14/11 8 Claims, 15 Drawing Figures US. Patent Oct. 7,1975 Sheet 1 of5 3,909,863

US. Patent Oct. 7,1975 shw 3 of5 3,909,863

U. atent Oct. 7,1975 Sheet40f5 3,909,863

US. Patent Oct. 7,1975 Sheet 5 of 5 3,909,863

BRIDGE CRANE GIRDER Large ships have for some time be built in such a way that they are assembled of prefabricated sections of several hundred, for instance 1600, megapont. For transporting such sections from the workshop to the shipyard, gantry cranes are employed which have a span width in excess of 150 m and a lifting height of up to 80 m. With travelling cranes built according to the box principle of these gantry cranes, the problem is encountered that the lower cord has, in view of the high pulling forces, to be conveyed thereby, at a given width to be made rather thick whereby the welding of the metal sheets forming the cord becomes rather difficult. For instance, with a bride beam composed of two parallel boxes and having a span width of 174 m, and assuming that the load to be handled by each box amounts to 1100 megapont, and that the lower cord of the box has a width of 2.4 m, a cord thickness of 150 mm is necessary.

It is, therefore, an object of the present invention to provide a bridge beam of great span width, for instance, for a gantry or a loading bridge, in such a way that con siderably smaller cord thicknesses will suffice.

This object and other objects and advantages of the invention will appear more clearly from the following specification in connection with the accompanying drawings, in which:

FIG. 1 diagrammatically illustrates, partly in vertical longitudinal section through the bridge beam and partly in view, a gantry with a bridge beam according to a first embodiment of the invention.

FIG. 2 represents a section taken along the line II II of FIG. 1, but on a larger scale than that of FIG. 1.

FIG. 3 shows partly a vertical longitudinal section through the bridge beam and partly a view of a portion of a second embodiment of a gantry with a bridge beam according to the invention.

FIG. 4 illustrates a vertical longitudinal section through a portion of the bridge beam of FIG. 3, but on a larger scale than the latter. FIG. 4a shows a detail in a different construction.

FIG. 5 is a section taken along the line V V of FIG. 4.

FIG. 6 is a section taken along the line VI VI of FIG. 4.

FIG. 7 shows an axial section on a larger scale than that of FIG. 6 through a device for tensioning and anchoring a cable bundle.

FIG. 8 is a section taken along the line VIII VIII of FIG. 7, but on a larger scale than the latter.

FIG. 9 is a section taken along the line IX IX of FIG. 4, but likewise on a larger scale than the latter.

FIG. 10 represents a section taken along the line X X of FIG. 7.

FIG. 11 shows a side view of a portion of a gantry with a bridge beam according to a third embodiment of the invention.

FIG. 12 is a section taken along the line XII XII of FIG. 11.

FIG. 13 illustrates, partly in a vertical longitudinal section through the bridge beam and partly in view, a gantry with a bridge beam according to the second embodiment of the invention, but with a modified cable guiding arrangement.

FIG. 14 is a section taken along the line XIV XIV of FIG. 13.

The bridge beam according to the present invention is characterized primarily in that at least the lower cord is relieved by preloaded cables.-

This arrangement brings about the advantage that the lower cord has, for instance, to be only one third as thick as has been necessary with the above referred examples of a heretofore known bridge beam. This thickness can be realized by means of the conventional welding method in a reliable manner in a relatively short time.

Referring now to the drawings in detail, the bridge beam of the embodiment shown in FIGS. 1 and 2 comprises a sheet metal box 1 which at one end merges with a fixed support 2 and at the other end rests on a link support 3. Within the sheet metal box 1 closely above the lower cord plate 4 there are provided cables 5 which extend nearly over the entire length of the bridge beam and are uniformly distributed over the width of the lower cord. The cables 5 are under a preload which is generated by hydraulic presses 6. The presses 6 engage the ends of the cables and rest on bearings 7 on the bridge beam. The cables 5 are covered by a sheet metal plate 8.

The preload acting upon the cables 5 may be so selected that the pulling stresses caused by the weight itself of the bridge beam are relieved in the lower cord and that in addition thereto a pressure preload is obtained in the lower cord plate 4. When the bridge beam is under load, the pressure preload is reduced by carriages and suspended loads so that when the life load corresponds to the admissible load capacity, a pulling stress will occur in the lower cord which amounts, for instance, only to one third of the pulling force as it occurs under the same condition in the lower cord of customary design. Consequently, the lower cord plate 4 can be made relatively thin so that it can be welded in a reliable manner.

With the embodiment according to FIGS. 3-10, the bridge beam of a gantry crane consists of a plurality of sheet metal boxes 10 which are spaced from each other and are connected at their ends. The fixed support is again designated with the reference numeral 2 whereas the link support is again designated with the reference numeral 3. In each of the sheet metal boxes 10 there are guided two bundles 9 of preloaded cables in such a way that only in an intermediate or central section A they extend closely above the lower cord 11 and from there extend at an incline in upward direction. The deviation of the cable bundles at the ends of section A is effected by means of saddle bearings 12. These bear- Zngs 12 comprise segments 13 which below girders 14 are journalled in joints 15 with their axes extending transverse to the bridge beam. The cable bundles 9 rest from below against the segments 13 and are received by circular grooves of the segments 13. The centers of curvature of the grooves are located in the axes of the joints 15.

The cable bundles 9 are in the vicinity of the ends of the boxes 10 anchored closely below the upper cord plate 16. To this end, the individual cables are out of one holding clamp 18 at each end of a cable bundle 9 extended outwardly while spreading in a fan-like manner. The individual cables, for instance nineteen individual cables, have a hexagonal cross section and extend parallel to each other while being combined to a cable bundle 9 as shown in FIG. 9. As counter bearing for all individual cables 17 of one bundle 9 there is employed a segmental support 19 which is so curved that the center lines of the spread-out individual cables are perpendicular thereto. Each of the individual cables is passed with play through a bore 20 of the segmental support. Therebehind the ends of the individual cables 17 are connected to a sleeve 21. To this end, the individual wires 22, for instance thirtyseven wires, of the individual cables 17 are spread out in a conical opening which widens in the direction away from the support 19, and are held fast by a cast-in mass. The wires 22 extend parallel to each other in the cables 17, which means they are not twisted.

For tensioning each individual cable 17, a hydraulic press is arranged at each end of the cable. The cylinder 24 of the press is mounted on a supporting pipe 25 which with play extends around the sleeve 21 and engages the segmental support 19. The piston rod 26 which extends out of the cylinder 24 through a stuffing box carries a coupling head 27 which by means of a thread is screwed onto the front end of sleeve 21. Connected to the cylinder 24 is a conduit 28 for conveying liquid under pressure. When through this conduit 28 liquid under pressure is introduced into the cylinder 24, sleeve 21 is pulled toward the left (FIG. 7) so that the individual cable will be tensioned. After the required preload has been reached, lining pieces in the form of divided annular discs 30 are inserted between the rear end face of sleeve 21 and the segmental support 19 through openings 29 in sleeve 25 in such a way that the sleeve 21 will rest by means of the discs 30 against the segmental support 19. In this way, the individual cable 17 is anchored at the obtained preload so that the hydraulic presses at the ends of the cable are relieved.

In view of the preload to which the cables 17 are subjected, upwardly directed forces are through the bearings l2 conveyed to the boxes of the bridge beam. Accordingly, the weight itself of those portions of the boxes 10 which are located within the regions A is supported by the cable bundles 9. Moreover, by means of the cable bundles 9, pulling forces are conveyed into the upper cord plates 16 which are slightly bent upwardly in the centers thereof. When the bridge beam receives a life load, the latter is in the lower cord absorbed to a major portion by the cable bundles, and the pulling forces conveyed by the cable bundles into the upper cord plate 16 are reduced so that at these places lower pressure forces will occur than would be the case if the bridge beam were not equipped with the preloaded cable bundles. Therefore, a considerable saving in material is realized not only in the lower cord but also in the upper cord. Also in this instance smaller thicknesses of the cord plates will suffice so that the welding operations will be facilitated.

The preload of the cable bundles may be realized, instead of using the

hydraulic presses

24, 26, by pressing the segments 13 of the bearings 12 downwardly by correspondingly arranged hydraulic presses 50, one of which is shown in FIG. 4a, and by fixing the segments 13 in their postion after the desired preload has been obtained, *In this instance, the individual cables are anchored at their ends without the employment of hydraulic presses.

*for example by means of a female screw 51 on the lower end of the piston 52 of the hydraulic press 50 abutting upon the lower end of the cylinder 53 of this press.

section A they extend closely to each other but diverge toward the segmental supports 19. This brings about that the boxes 10 will, in conformity with the preload of the cable bundles 9, have an increased resistance capability against forces acting in the driving direction of the gantry. Such an effect is realized to an increased extent when, in conformity with FIGS. 13 and 14, the cable bundles 9 in the intermediate or central section A extend closely to the side walls of the box which forms the bridge beam and from the bearing 12 are passed to the respective oppositely located side walls so that they cross each other in those sections of the bridge beam which are adjacent to the central section A.

According to the embodiment of FIGS. 11 and 12, the preloaded cable bundles 31 are guided outside of and below the bridge beam. The bridge beam consists of two relatively low sheet metal boxes 32 which are arranged in spaced relationship to each other and on which there are arranged two trolleys or

carriages

33, 34. From the two ends of each box 32 there extends a cable bundle 31 at an incline in downward direction to the supports 35 which extend downwardly from the box 32. The cable bundle 31 extends horizontally in the intermediate section A of the bridge beam between the supports 35. Hydraulic presses 36 for tensioning the cable bundles are arranged at the ends of the cable bundles. However, instead the cable bundles 31 may also be tensioned by pressing the supports 35 downwardly by means of hydraulic presses and then anchoring the same. Also by this arrangement of the cables the bridge beam is considerably relieved so that a saving in sheet metal will be realized and the welding operations will be facilitated. by means of the preloaded cable bundles, a camber of the bridge beam can be realized if desired.

It is, of course, to be understood that the present invention is, by no means, limited to the specific showing in the drawings and the employment of bridge beams built in the form of boxes, but also comprises any modifications within the scope of the appended claims and is also applicable advantageously in connection with bridge crane beams of the latticework type.

What we claim is:

1. A bridge crane girder of steel with great span width, especially of the box type construction, which has an upper cord and a lower cord, and pre-loaded cable means combined with said girder at least in part for reinforcement against force in horizontal direction and relieving at least said lower cord, said pre-loaded cable means being arranged completely within the profile of said girder, said pre-loaded cable means having a central section extending closely along a central section of said lower cord and having end sections respectively ascending from the ends of said central section of said pre-loaded cable means at least approximately toward the ends of said upper cord, said pre-loaded cable means being combined to form cable bundles, and saddle means rotatably mounted at the ends of said central section of said lower cord and deviating said cable bundles upwardly.

2. A girder according to claim 1, which includes means operatively connected to said saddle means for adjusting the same to tension said cable means.

3. A girder according to claim 1, in which at least two cable bundles in said girder have their ends offset rela- I said girder and from the ends of said last mentioned central section extend in the end portions of said girder at an incline to the respective oppositely located side walls of said girder.

5. A girder according to claim 4, in which said cable bundles cross each other within the end sections of said girder.

6. A bridge crane girder of steel, especially of the box type construction, which has an upper cord and a lower cord, and pre-loaded cable means associated with said girder and relieving at least said lower cord, said cable means being combined into cable bundles having the cable means thereof at one end of said bundles fan out, and which includes sleeve means having said fanned out portions of said cable means connected thereto, hydraulic power operable means operatively connected to said sleeve means for exerting a pulling force upon said sleeve means and thereby upon said cable means to pre-load the same, and holding means operable independently of said power operable means to maintain said cable means preloaded, a tubular body, abutment means located at one end of said tubular body and arranged stationarily relative thereto, said holding means being detachably arranged between said sleeve means and said abutment means, said tubular body having that end portion which is adjacent said abutment means provided with a window for passing said holding means therethrough, said hydraulic power operable means being mounted on the other end of said tubular body.

7. A girder according to claim 6, which includes supports connected to said lower cord and extending downwardly therefrom, and in which said pre-loaded cables extend from the girder ends in downwardly inclined direction to the lower end portions of said supports.

8. A bridge crane girder of steel with great span width, especially of the box type construction, which has an upper cord and a lower cord, and pre-loaded cable means combined with said girder at least in part for reinforcement against force in horizontal direction and relieving at least said lower cord, said cable means being combined into cable bundles having the cable means thereof at one end of said bundles fan out, sleeve means having said fanned out portions of said cable means connected thereto, hydraulic power operable means operatively connected to said sleeve means for exerting a pulling force upon said sleeve means and thereby upon said cable means to pre-load the same, and holding means operable independently of said power operable means to maintain said cable means pre-loaded.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent 3,909,863 Dated October 7, 1975 Inventor) Karl Macrande'r et a1 It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

- [73] Assignee: Fried. KTupp Gesellschaft mit bGSChTHIIktflI Haftung, Essen, Germany Signed and Scaled this sixth D y of January 1976 [SEAL] A ttest:

RUTH C. MASON C. MARSHALL DANN Arresting Officer (mnmissiuner ufPaIenis and Trademarks

Claims

3. A girder according to claim 1, in which at least two cable bundles in said girder have their ends offset relative to their central portions in a direction transverse to said girder.

4. A girder according to claim 3, in which said two cable bundles extend closely along a central section of said girder and from the ends of said last mentioned central section extend in the end portions of said girder at an incline to the respective oppositely located side walls of said girder.

6. A bridge crane girder of steel, especially of the box type construction, which has an upper cord and a lower cord, and pre-loaded cable means associated with said girder and relieving at least said lower cord, said cable means being combined into cable bundles having the cable means thereof at one end of said bundles fan out, and which includes sleeve means having said fanned out portions of said cable means connected thereto, hydraulic power operable means operatively connected to said sleeve means for exerting a pulling force upon said sleeve means and thereby upon said cable means to pre-load the same, and holding means operable independently of said power operable means to maintain said cable means pre-loaded, a tubular body, abutment means located at one end of said tubular body and arranged stationarily relative thereto, said holding means being detachably arranged between said sleeve means and said abutment means, said tubular body having that end portion which is adjacent said abutment means provided with a window for passing said holding means therethrough, said hydraulic power operable means being mounted on the other end of said tubular body.