RU2196099C2 - DEVICE FOR REINFORCEMENT OF CRANE RUNWAY h-BEAM - Google Patents

Abstract

FIELD: mechanical engineering. SUBSTANCE: invention relates to metal structures of heavy-duty cranes. proposed device for reinforcement of crane runway beam has reinforcement channels and four-head cross rail. Beam to be reinforced has upper chord, wall and lower chord interconnected by welding and also support and intermediate stiffening ribs. Channels are installed symmetrically relative to rail on upper chord of crane runway beam, with their flanges pointed outwards. Four-head rail is connected by horizontal walls with flanges of said channels. Lower head of rail is in contact with upper chord of beam to be reinforced over its wall. Vertical load from main wheels of crane is taken by upper head of rail, and horizontal load from guide rolls of crane, by side heads. EFFECT: increased service life and improved load-bearing capacity of crane runway beam. 3 dwg

Description

 The invention relates to metal structures, mainly crane with heavy duty cranes (8K, 7K).

 The amplification given in the textbook [1, p. 374], we take for the prototype. The prototype has significant disadvantages. Difficult ceiling welds are used. In this case, the stress concentration reaches four units. The possibility of the appearance of fatigue cracks at the attachment points of transverse stiffeners is not eliminated. At the upper ends of the welds, the effective stress concentration coefficient also reaches four units.

 For the prototype we take the connection of the rail with a crane beam using channels [2]. It is known that the rail is made with four-headed cruciform cross-section [3]. Install this rail on the crane beam.

 The technical result of the invention is to increase the durability and bearing capacity of the crane beam.

 It is achieved by the fact that the crane beam contains channels, symmetrically mounted relative to the rail on the upper belt of the crane beam with the orientation of their shelves outward. Channel bars are connected to this beam with studs with guaranteed interference fit.

 The rail is made of four-headed cross-shaped in cross section and is connected by horizontal walls to the shelves of said channels with the contact of its lower head with the upper belt of the reinforced beam above its wall. At the same time, the vertical load from the main wheels of the crane is absorbed by the upper head of the rail, and horizontal from the guide rollers of the crane by the lateral heads.

When reinforcing, the old crane rail and its fasteners are dismantled. Then, holes are drilled in the shelves of the reinforcing channels, corresponding to the holes in the upper belt of the beam. The channels are mounted on the upper belt symmetrically relative to the vertical plane of the beam wall with the shelves outward and connected to the belt with studs with guaranteed interference fit. The studs are similar to friction bolts and provide a connection without slipping. Then, from the end of the beam, the four-headed cross-shaped rail in cross section is progressively pushed until the holes in its horizontal walls and channel shelves are aligned. In this case, the joints of the rails are placed in 1/3 ... 1/4 of the span of the beam. Connect the rail with the channels with studs in a single unit and operate the rail until the upper head is worn. In this case, the vertical load P from the main wheels of the crane perceives the upper head of the rail, and the horizontal T from the guide rollers of the crane - the side heads. The lower head of the rail is in contact with the belt of the reinforced beam above its wall. When the upper head is worn, the rail is turned 180 ^o and continue to operate until the rail is completely worn.

 Comparison of the developed device with the prototype shows its significant difference, namely: the four-headed cross-shaped rail in cross section is connected by horizontal walls to the channel shelves with studs with guaranteed interference fit and forms a single unit with the beam. The four-headed cross-shaped rail in the section and the channels connected to it without slipping are reinforcing elements that work as part of the section of the entire structure.

 Thus, the claimed device is significantly different from the prototype.

 Figure 1 shows a device for reinforcing a crane beam; figure 2 - fragments of reinforced crane beams and their conjugation with each other (column not shown); in FIG. 3 shows the reinforcement of the crane beam with a four-headed rail and channels.

 The crane beam 1 is reinforced with channels 2 and a four-headed rail 3. These elements are connected to each other and to the reinforced beam by means of friction pins 4. The retractable crane beam 1 contains an upper belt 5, a wall 6 and a lower belt 7. These elements are connected to each other by welds . It is also equipped with supporting 8 and intermediate 9 stiffeners.

 Amplification is as follows. In accordance with the holes in the belt 5, drill holes in the shelves of the channels 2. Remove the fastenings of the old rail and mount the channels 2 on the upper belt 5 symmetrically with respect to the rail, orienting the shelves outward. At one end of the workshop, a new four-headed cruciform rail 3 is connected to the old rail and the connected rails are steadily moved [4, 5] along the workshop in a known manner, pushing the new rail to replace the old one. Rail joints are placed in 1/3 ... 1/4 of the beam span.

 The movement is made to match the holes in the shelves of the channels 2 and in the necks of the four-headed cross-shaped rail 3 and connect it to the channels 2 with friction pins. The rails also join together (not shown). Four-headed cruciform rails overlap the joints of split crane reinforced beams. In the lower part of the beams 1 between the supporting ribs 8 install spacers 10, ensuring continuity of the path. The crane runway has been converted from a cut to a continuous cut and therefore its load-bearing capacity is significantly increased. An even greater increase in bearing capacity was due to an increase in section height.

 The economic effect arose due to the increased durability of the crane beam.

 Fatigue cracks are excluded in the reinforced crane beam, since the reinforcing channels 2 and the four-headed rail 3 increased the moments of inertia of the upper belt during bending by 7 ... 8 times, and during torsion by 1.5 ... 2 times and this ensured the construction in the zone of unlimited durability [6]. The service life of the rail to its full wear has doubled. At the same time, the bearing capacity of the entire structure increased by 20 ... 30%.

LITERATURE
1. Belena E.I. Metal constructions. M .: Stroyizdat, 1986.

 2. Nezhdanov K. K., Nezhdanov A.K. Nezhdanov device for reinforcing the crane structure. Patent of Russia 2067646. Valid from 10.10.1996.

 3. Nezhdanov K. K., Nezhdanov A. K. Crane rail. Patent of Russia 2089698. The priority of the invention from 5.12.1994.//Byul. 25, 1997.

 4. Nezhdanov K.K. etc. A method for replacing a crane rail: a.s. 358248, M. Cl. B 66 C 7/08 // B.I. 33, 1972.

 5. Nezhdanov K.K. etc. A method for replacing a rail track: 1146353, M. Cl. B 66 C 7/08 // B.I. 11, 1985.

 6. Nezhdanov K.K. Perfection of crane structures and methods of their calculation: The dissertation for the degree of Doctor of Technical Sciences, Penza, 1992.

Claims (1)

 A device for reinforcing a crane beam containing channels that are symmetrically mounted relative to the rail on the upper belt of the crane beam with the shelves oriented outward and connected to this beam by pins, characterized in that the rail is made four-headed crosswise in cross section and is connected by horizontal walls to the shelves of said channels with contact of its lower head with the upper belt of the reinforced beam above its wall, while the vertical load of the crane’s main wheels is perceived by the upper head of the rail, and burn Zonal from the guide rollers of the crane - side chapters.

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