RU1791340C - Metal crane supporting construction - Google Patents

Abstract

Usage: for the reconstruction and construction of crane structures, mainly heavy duty. SUMMARY OF THE INVENTION: a metal crane structure comprising a wall, supporting stiffeners and a support, and an upper rail made of a closed loop in the form of a horizontal sheet and two bent overlays with mutually perpendicular end sections for fastening respectively to the wall and along the beam and transition section connecting the end. The rail is attached to the upper one by means of double-sided bent shock absorbers. The transition section of the lining is made in a curved S-shape, and the wall is brought into a closed loop of the upper race until it stops in the latter, with the separation of the closed loop into two compartments. The fastening of the end sections to the post and wall is made by high-strength bolts. 1 s.p. f-ly, 4 ill ..

Description

And

Fertility refers to the reconstruction and construction of crane works

niy e eimushestvennogo heavy mode

s (7K-8K).

The famous metal I-beams

sub

there is a movable beam containing a vertical wall and horizontal lines along the line, and between the upper line on the line and the wall there are two broken cross-sections symmetrical with respect to the last lining, forming a closed triangular section with a sheet of the upper line. The supporting ribs are welded to the self, wall and plates. Crane beams should not only be strong, but also hardy. Local concentrated dynamic actions are transmitted to the upper zone of the beam through the rail:

Piojc. - vertical, with eccentricity e; ;

Tioe - horizontal, applied to the rail head © with an eccentricity equal to height 1 of the hp rail;

MiocKp Pioc e + Tioc hp is the torque causing fatigue failure and decommissioning the beam.

The disadvantages of the known solution are as follows.

The endurance of the welded joint of the support rib with the broken-in overlays is low, since the effective stress concentration coefficients reach four units at the upper end of the weld joint in the Pioc, Tioc, and MiocKp heavy impact zones (Kef 4). The simultaneous use of welded and bolted joints is unacceptable, since in welded joints the effective stress concentration factors are higher and the compliance is greater for bolted ones. The endurance of broken linings in the cross section is small, since at small radii of curvature in the bending zones Kef 2–2.5.

. The upper beam from the beam under the rail at each passage of the wheel works on places h | ABOUT

00 4 O

bending and fatigue cracks are possible in this zone.

The purpose of the invention is to increase the endurance and bearing capacity of a crane structure.

The goal is achieved by performing the transition section of the lining in a curved S-shape, with the wall brought into a closed loop of the upper race until it stops in the latter with a divided closed loop into two compartments and is supported by end sections of the overlays bent upwards, and the latter are fastened to the wall and along the wall with high strength friction bolts.

The sheet of the brake beam. It is located between the rail and the upper one on the catfish and is connected to the last with the same bolts.

The bearing capacity and endurance of the tilt structure is also enhanced by the implementation of shock absorbers that attach the rail to the beam, continuous along the entire length of the latter, with a section adjacent to the rail neck and repeating its form by interconnected by bolts passing through the neck of the rail, and with high-strength bolts attached to the horizontal sheet of the upper race,

The supporting ribs of the beam are made of rolling profiles (corners or Tauri), equipped at the ends with flanges, which ensure their connection with the upper and lower soms, and the ribs are bent in a plane perpendicular to the wall, installed with a gap between the plates and the upper part of the wall tightly adjacent and connected to its lower part by means of friction high-strength bolts.

Figure 1 shows a metal crane structure, general view; figure 2 is the same section; in Fig.Z - supporting rib; figure 4 - line regression Weller.

The crane crane structure consists of rail 1, brake beam 2 and crane beam 3. Rail 1 and crane beam 3 are connected by shock absorbers 4 to each other, and brake beam 2 is sandwiched between them, the top with crane crane 5, the beam consists of two bent parts b and sheet 7. The vertical wall 8 is brought to the end with its end in sheet 7 and divides the closed loop into two compartments. The bent part 6 contains a vertical section a and a horizontal section b, interconnected by an S-shaped section S. Symmetric sections a of the plates 6 reinforce the wall on both sides and are connected to it by high-strength bolts or studs 9, and the horizontal sections are tightly adjacent

to the sheet 7 from below and connected to it by high-strength bolts 9. The lower one along with 10 is connected to the wall 8 as in a conventional beam. The shock absorber 4 has a section c, copying the shape of the neck of the rail, and section d is tightly adjacent to the beam from above. Cushioning is provided by corrugation.

The metal crane construction works as follows. When the concentrated Pioc force transmitted from the crane wheel acts on the rail 1, it is perceived by the rail and distributed to the upper beam. Closed loop 5 transfers these local influences in two ways: on the end of the wall and through a bolted connection to the upper part of the wall 8. It is rational to distribute the force transmission equally on one and the other. In this case, the local stresses in the upper part of the wall, with the central position of Pioc., Are halved. Regulation of the transfer of force P | 0s. in one or another way it is carried out by corrugating the wall of the beam, thereby changing its vertical compliance. Since the upper seam is absent, the effective concentration coefficient is reduced to its minimum, i.e. Kef 1. In the beam (prototype) with lack of fusion in the seam Kef 4, i.e. a four-fold decrease in the effective concentration coefficient occurred. Thus, a voltage drop of eight times occurred.

When exposed to the upper with the proposed crane beams concentrated local moment

MiocKp Pioc e + Tioc .hp, where e is the eccentricity of the vertical force, and

hp - rail height.

The upper curve is twisted and local stresses ± 0у1scr appear in the beam wall, which are summed with the Oyioc stresses with a central application

FORCES P | OS.

20yloc 0yloc ± OylocKp.

The magnitude of the stresses Oy | 0scr primarily depends on the moment of inertia of the upper beam beam per torsion 1Pac.

In the proposed design, the upper roof is closed, consisting of two compartments. The moment of inertia of the torsion of such a belt is several tens of times greater than that of a flat sheet, so a proportional decrease in stresses and an increase in endurance occur.

Consequently, a qualitative change in the operation of the crane beam will occur.

Figure 4 shows the Weller regression line, which divides the entire area of dynamic work into three zones: I 1. Fatigue failure.

2. Limited endurance, in which modern crane structures (prototype) work.

3. Unlimited endurance in which railway structures work and in which crane structures should work by analogy.

As a result of the proposed construction of the crane runway, an over-cumulative effect arises, since a conventional crane beam (prototype) works in sohe limited endurance, and is proposed in the unlimited endurance zone CTJI. . .

 The beam is manufactured on traditional equipment of metal construction plants. Sheet metal blanks are cut with a guillotine. Holes are preliminarily pressed in the blanks of the upper strand, holes are drilled to the required diameter in the drill, then bending is performed on a bending machine.

Initially, the lower weld is welded to the beam wall, then in a special mill, the upper weld parts are connected to the beam wall with the brake beam.

When tightening the bolts of the upper bolt joint, the sheet is tightly pressed against the end of the wall 8.

 The rail 1 is initially connected by high-strength bolts 9 to shock absorbers 4, and then the longitudinal axes of the rail and beams are combined and connected to each other by high-strength friction bolts 9.

Thus, the rail 1 and the shock absorbers 4 are combined with the beam 3 in a single unit. The moment of inertia of the entire cross section increases

beams 1X and the moment of resistance Wx and, accordingly, the stresses when the beam is bent decreases.

At the same time, the moments of inertia and the moments of resistance of the upper belt with local bending and torsion increase. Local stresses decrease below the endurance limit and the beam passes from the restricted zone to the unlimited endurance zone, which ensures reliable operation for at least 50 years of intensive use.

Claims (2)

1. A metal crane structure containing a wall, supporting stiffeners, a strut, the upper of which is made of a closed loop in the form of a horizontal sheet and two bent plates, with mutually perpendicular annular sections for fastening to the wall and along the beam and transition sections, respectively . a lump connecting the end, a rail attached to the upper one by means of double-sided bent shock absorbers, which means that, in order to increase the bearing capacity and endurance, the transition section of the lining is made curved S-shaped, the wall is brought into a closed loop the upper race to the end in the latter with the separation of the closed loop into two compartments, and the fastening of the end sections to the wall and wall is made by high-strength bolts. 2. The design according to claim 1, with the fact that the shock absorbers are made continuous along the entire length of the beam with a section adjacent to the neck of the rail and repeating its shape, and are interconnected by bolts, the passage through the neck of the rail, and attached to the horizontal sheet of the upper race with high strength bolts. Zone limited maturity Destruction zone