CH714681A2 - Electricity pylon consisting of one or two single masts. - Google Patents

Abstract

A mast made of thin-walled steel tubes with material-optimized cross-sections with respect to usually direction-dependent different forces, which can be used as a single mast or a double mast. The basis is a single mast with a basic geometry, which is composed of arcs or straight lines or arcs and straight lines. The mast cross-section is preferably reinforced on at least one of its outermost sides in the form of steel-concrete composite cross-section, by welded-on rolled sections or by thickened steel sheets. The double mast consists of two identical individual masts (1), which are connected with rigidly connected cross bars (6) to a Vierendeel framework, which has a different load-bearing resistance in the main direction and the secondary direction. The height of the mast consists of several segments that can be joined together on the construction site by means of a flange joint. The single mast as well as the double mast can be equipped with outriggers and suspension insulators, insulated trusses or other equipment. The mast can be used in particular as an overhead line, but also for other purposes.

Description

Description: The present application relates to a freestanding overhead line mast made of steel tube according to the preamble of claim 1.

The supply of electrical energy takes place via power line networks, which are created as underground cables or overhead overhead lines. Light overhead constructions made of wood or concrete with small mast heights are usually used for overhead lines with low transmission voltages.

In the medium voltage range, steel tube masts, reinforced centrifugal concrete masts or steel lattice masts are usually used. The mast heights are usually in the range between approx. 25 to 50 m.

In the highest voltage range from 220 kV to 400 kV, overhead line masts are typically designed as steel lattice masts. Such constructions have been described many times. This traditional type of construction enables relatively light masts. These masts can be fully assembled on site at the construction site or components can be preassembled in the manufacturing plant, which are then assembled on site using a mobile crane or helicopter.

The masts are equipped with cantilevers (cross beams), on which the conductor cables are attached by means of insulating hanging elements (insulator chains).

Steel lattice masts have several disadvantages:

a) You need a wide cable route, because on the one hand the masts have large floor plan dimensions and the hanging insulators require an additional safety zone due to swinging out under the influence of wind.

b) In addition, the maintenance costs of the masts are high due to the slender steel construction.

c) Furthermore, the total assembly effort is high and relativizes the low material costs when considering the total costs.

d) The appearance of these masts is not up to date.

Steel pipelines with circular or a polygonal cross-section approximating a circular shape are used for transmission lines in the highest voltage range (220 kV to 400 kV). Such masts have been described in various ways. Steel tube masts are slimmer than steel lattice masts. However, they are only economically feasible up to limited heights and load capacities. If they are used for greater heights and greater forces, they require very large cross-sectional dimensions and wall thicknesses and can only be manufactured and assembled by specialized companies.

[0008] Ceramic has traditionally been used as the material for the insulators. In this case, the conductor ropes are suspended from insulating "pull chains" and swing out under the influence of wind as mentioned above. Such ceramic insulators have been described in various ways.

Instead of ceramic insulators, glass or plastic insulators (composite insulators) are increasingly being used today, which have already been described in various ways. Insulated suspension systems can be manufactured with plastic insulators, in particular, with which there is no need for crossbeams on the masts. These so-called insulating crossbars each consist of an insulating tension rod and compression rod, which are arranged as a triangle and can be freely rotated about an axis with an inclination of approximately 22 degrees with respect to the vertical mast. The conductor cables are thus fixed in the transverse direction of the overhead line and can move freely in the longitudinal direction. As a result, the space required for an overhead line (line width) can be reduced by the “swing-out dimension” compared to the type of construction with hanging chains. Such systems have already been described, e.g. in patent EP 1 873 331 A2.

The assembly of such Isoliertraversen is structurally difficult to accomplish in steel lattice masts and is better suited for the use of tubular steel masts.

The present invention is therefore based on the object to describe an overhead line mast that does not have the disadvantages mentioned above.

The solution to this problem is based essentially on the knowledge that the force applied to overhead line masts is generally different in size along the overhead line axis and transversely to the overhead line axis.

Analogously, the mast according to the invention is normally not designed like conventional masts with a concentric cross-section, but instead has a material-optimized cross-section in the main direction and the secondary direction, which is at right angles thereto, which is adapted to the normally different loads.

This material optimization of the cross section is achieved with three different means that can be combined with each other.

CH 714 681 A2

a) Formation of the basic geometry of the cross section in elliptical geometry or approximation to an elliptical geometry

b) Reinforcement of the outermost areas of the cross-section of the basic geometry

c) Rigid connection of two masts to a Vierendel framework.

If the action of force in the main direction and the secondary direction - at right angles thereto - is different, an elliptical or an ellipse-approximated basic cross section is proposed as the basic geometry. The optimal choice of this geometry means that the load-bearing resistance of the mast can be adjusted very precisely to the force. This results in a minimization of the material expenditure and the weight for the mast construction.

For the reinforcement of the basic geometry of the cross-sections, a concrete cross-section preferably introduced at the installation site or steel profiles welded in the manufacturing plant are proposed, which run from the beginning of the mast over a certain height towards the end of the mast.

One of the basics of the invention is thus to increase the load resistance and minimize the weight by reinforcing the steel cross-section with concrete or a concrete-like material to form a concrete-steel composite cross-section on the diametrically opposite sides. This concrete reinforcement is preferably installed on site at the installation site in predetermined cavities of the mast cross section. Self-compacting concrete is preferably used for this. As a result, the load-bearing capacity of the steel tube cross section can be increased considerably in a very economical way.

Instead of reinforcement with concrete, the cross section can also be reinforced with steel. For this purpose, either rolled sections or folded sheets with a large sheet thickness are welded onto the diametrically opposite sides of the cross section. This method also leads to a significant increase in the load-bearing capacity of the cross-section.

In order to optimally adapt the load-bearing capacity and the deformation behavior of the mast over the entire mast height to the effects, the mast cross section is conical over its height. The largest cross-sectional dimension lies at the foot and tapers towards the top of the overhead line mast.

If the action of force in the main direction and the - at right angles thereto - secondary direction is different, the taper in the main direction is polynomial and linear in the secondary direction. This results in high economic efficiency for the manufacture of the mast.

[0021] Furthermore, the wall thicknesses of the steel tube cross section are normally varied in segments over the mast height. The wall thicknesses are greatest at the foot and smallest at the top.

Instead of a continuous taper, the mast can also be cylindrical in segments and thereby be approximated to a conical geometry.

The height of the mast consists of several segments. The length of the segments depends on the manufacturing options in the factory as well as the transportation options and installation conditions.

The individual segments are typically non-positively connected at the installation site by means of a screw joint, also called a flange joint. Individual manufacturing segments can also be joined together beforehand in the factory, preferably by a welded connection, if the transport options and installation conditions permit.

To further increase the load capacity, two identical single masts are connected to a frame by means of rigid cross bars. This type of support structure is based on a tried and tested structure known as the Vierendeel beam.

The distances between the crossbars of the Vendeel beam decrease upwards in a harmonious ratio. This results in a balanced load on the mast post and an attractive appearance.

The crossbars of the Vierendeel beam are non-positively welded to the mast post and connected in the middle by means of a screw for the assembly of the mast.

The mast segments of the individual mast consist of two identical half-shells which are welded together in a non-positive manner in the manufacturing plant. This enables the crossbars to be correctly connected to the mast as a frame corner.

The single mast or the Vierendeel beam consisting of two masts can be equipped with brackets and hanging insulators or with insulating beams or with other equipment.

The foundation of the mast is realized according to geological criteria with known and proven foundation methods such as block foundation or slab foundation with quiver.

The main advantages of the mast according to the invention compared to conventional overhead line masts are that the construction can be made slimmer than lattice masts. In addition, the installation of Isoliertraver3

CH 714 681 A2 sen easier to do than with lattice masts. The greater slenderness of the mast and the use of insulating cross beams enable the construction of overhead lines with less space in the field.

Compared to conventional single-stemmed, concentric, not reinforced tubular steel masts, the mast according to the invention is lighter and therefore more economical.

Since the mast according to the invention is made of thin-walled steel sheets, it can also be produced by medium-sized manufacturers without capital-intensive special facilities. Even steel construction companies that do not have their own operating facilities for folding or rolling sheet metal can obtain custom-made sheet metal from corresponding specialist companies.

Another advantage over conventional overhead line masts is the attractive appearance, which increases the acceptance of the mast in the landscape.

The mast according to the invention can also be used for other purposes, for example as a radio mast or as a wind mast or as an advertising mast or as a light mast or as a pillar or pylon.

The invention is explained in more detail with reference to drawings. It shows:

1: basic geometries of the mast cross section of a mast segment,

2: top view of an overhead line mast with several mast cross sections,

3: View of the polynomial taper in the main direction of the overhead line mast,

4: View of the linear conicity in the secondary direction of the overhead line mast,

5: representation of the two identical half-shells of a single mast,

6: View of a double mast, consisting of two identical single masts,

7: plan view of FIG. 6,

8: double mast with mast segments and crossbars,

Fig. 9: Floor plan with rigid connection of the crossbars,

Fig. 10: Section A-A of Fig. 9,

Fig. 11: Section B-B to Fig. 9,

Fig. 12: Transmission tower with brackets and hanging chains,

Fig. 13: overhead line mast with insulating crossbars,

Fig. 14: Reinforcements of a cross section with concrete in the floor plan,

Fig. 15: Reinforcement of a cross section with rolled profiles or sheets,

Fig. 16: guy mast, view transverse to the direction of the cable,

Fig. 17: guy boom according to Fig. 16, view in line direction,

Fig. 18: guy mast in the floor plan according to Fig. 16,

Fig. 19: Angled mast, view to bisect the angle,

Fig. 20: Angled mast, view in the bisector according to Fig. 19,

Fig. 21: Angled mast, floor plan for Fig. 19,

Fig. 22: Insulating traverse,

Fig. 23: Transmission tower with a cylindrical design.

Fig. 24: View of a double mast consisting of two identical single masts with concrete reinforcement, shown in cross section AA. Fig. 1 shows different basic geometries G1, G2, G3, G4, G5, G6, G7, G8 of the mast cross section of a Mast segments, which are composed of arches or straight lines or arches and straight lines. These basic geometries can be used for all of the following descriptions.

CH 714 681 A2 The overhead line mast shown in FIG. 6 is designed as a double mast and is composed of two identical individual masts 1, which can also be used as a single mast. The two individual masts 1 consist of several mast segments 2. The mast segments 2 are thin-walled tubular steel cross sections with basic geometries, as the examples in FIG. 1 show. The individual mast segments 2 are non-positively connected to one another. The two identical individual masts 1 are connected to one another by means of rigid cross bars 6, which are joined together in the middle of the axis of the two individual masts by means of a screwed tab joint.

In this type of mast construction with the two identical individual masts 1, the greatest stress acts transversely to the direction of the overhead line 34, as can be seen from FIG. 7.

Fig. 8 illustrates in a view the individual components of the mast construction according to the embodiment in Fig. 6. The length of the individual mast segments 2 is determined based on the manufacturing options and the installation conditions. The distances between the crossbars 6 of the overhead line mast decrease upwards in a harmonic relationship so that the distance a2 is a1 times the factor f, the distance a3 = a2 times the factor f and so on. The factor f is determined depending on static considerations and aesthetic aspects and is usually in the range between 0.65 and 0.85. The individual mast 1 consists of a steel tube, the basic geometries of which are constructed as shown in FIG. 1.

Fig. 2 shows a plan view of a single mast with the top mast cross section Q1 and the bottom mast cross section Q5 and three mast cross sections Q2, Q3, Q4 in between. The mast geometry is preferably conical over the entire height in the main direction (HR) and in the secondary direction (NR) of the cross section. The wall thickness 3 decreases in segments upwards.

Fig. 3 shows the taper of a mast with the mast beginning 7 and the mast end 8 in the main direction (HR) of the cross section, which has a polynomial course.

4 shows the course of the taper in the secondary direction (NR) of the cross section, which runs linearly if the basic geometry does not have a circular shape or a polygonal shape approximating a circle.

Instead of a conical course, the mast can also be cylindrical over its entire height with stepped, upwardly tapered cross sections as shown in FIG. 23.

Fig. 5 shows in plan a mast segment 2, which is made of two identical half-shells 13a, 13b, which are welded together at the joints 14a, 14b by means of longitudinal welds. The dividing line of the two identical half-shells 13a, 13b lies on the diagonal 12, which is not on one of the four intersection points S1, S2, S3, S4 of the main axis HA and - at right angles thereto - the secondary axis NA of the cross-sectional geometry, so that the chambers 15 for a possible concrete reinforcement 26 or the reinforcements with steel profiles 16 or folding plates are not affected, which can be seen in FIGS. 14 and 15.

In Fig. 9 an embodiment with rigid connection of the cross bar 6 is shown in plan. 10 shows the section A-A to FIG. 9 and in FIG. 11 the section B-B to FIG. 9 is shown. The cross bar 6 consists of two U-profiles which are welded over their entire surface to the outer shell 13a of a mast segment 2. To form a load-bearing frame corner, a first flange reinforcement 19 made of sheet steel is welded onto the upper and lower flange of the U-profiles 18. The identical inner shell 13a of the mast segment provided with a cutout 20 for the two U-profiles 18 can then be attached and welded to the outer, identical shell 13b at the connection points 14a and 14b. A second flange reinforcement 21 made of sheet steel is welded onto the upper and lower flange of the U-profiles.

In Fig. 12 an overhead line mast with brackets 22 (cross members) and suspended insulators 23 is shown. When equipped with hanging insulators, in addition to the normal space requirement, the overhead line requires a safety zone for the swing-out dimension 24 of the hanging insulators when the insulators are exposed to wind.

Fig. 13 shows an overhead line mast, which is equipped with insulating cross members 25.

Fig. 14 shows various examples of mast cross sections, which are designed by means of a reinforcement made of concrete 26 to a steel-concrete composite cross section.

15 shows two further variants of the cross-sectional reinforcement with steel profiles 16 welded to the diametrically opposite, outermost regions, or with welded thick-walled, bent steel sheets 17.

Fig. 16 shows an example of a guy mast in the analog design. Since with this type of mast construction the greatest stress acts in the longitudinal direction of the overhead line 34, the guy mast is rotated by 90 degrees compared to the example of FIG. 6, as can be seen from FIG. 18. 17 shows the view of this embodiment.

Fig. 19 shows an example of an angle mast in the analog design. In this type of mast construction, the greatest stress is normally in the direction of the bisector 35 of the overhead line 34. The main direction of support of the mast is therefore also in the bisector 35 of the overhead line, which is shown in FIG. 21. Since one of the electrical cable strands is passed between the two mast posts 36, the minimum distance between the two individual masts must be selected on the basis of electrotechnical criteria. The view of this embodiment is shown in Fig. 20.

CH 714 681 A2 Fig. 22 shows the principle of the insulating cross member. The horizontal pressure rod 27 and the oblique tension rod 28 of the crossmember are connected to one another at a common node 29, to which the electrical line or a bundle of lines 30 is attached. The insulating crossmember is attached to the mast by means of the lower attachment 31 and the upper attachment. The insulating crossmember can swing freely around an axis inclined by approx. 22 degrees compared to the vertical mast.

Fig. 24 shows a view of a double mast made of two identical single masts 1 with concrete reinforcement 26 and the crossbars 6. In section A-A the two single masts 1 and the crossbars 6 and the concrete reinforcements 26 are shown.

Claims (11)

claims 1. overhead line mast consisting of one or two individual masts (1), each consisting of at least one mast segment (2) and cross-sections (Q1, Q2, Q3, Q4, Q5) with basic geometries (G1, G2, G3, G4 , G5, G6, G7, G8), which are composed of arcs or straight lines or arcs and straight lines, characterized in that the basic geometries (G1, G2, G3, G4, G5, G6, G7, G8) of the mast cross sections ( Q1, Q2, Q3, Q4, Q5) are elliptical or circular or approximately elliptical or approximately circular and local reinforcements (16, 17, 26) are provided. 2. overhead line mast according to claim 1, characterized in that the wall thickness (3) of the mast segments (2) from the mast start (7) up towards the mast end (8) tapers preferably from mast segment to mast segment and that the mast cross-sections (Q1 , Q2, Q3, Q4, Q5) from the mast start (7) towards the mast end (8) either continuously or in steps. 3. overhead line mast according to claims 1 and 2, characterized in that in the main direction (HR) of the cross section, the reduction of the mast cross-sections (Q1, Q2, Q3, Q4, Q5) from the mast start (7) up towards the mast end ( 8) preferably approximates a polynomial curve of the first degree and in the secondary direction (NR) of the cross section the reduction of the mast cross sections (Q1, Q2, Q3, Q4, Q5) from the mast start (7) upwards towards the mast end (8) is preferably constant runs. 4. overhead line mast according to claims 1 to 3, characterized in that the mast cross-section (Q1, Q2, Q3, Q4, Q5) consists of at least two preferably identical half-shells (13a, 13b), the connection points (14a, 14b) of which are not lie on one of the four intersection points (S1, S2, S3, S4) of the main axis (HA) and - at right angles to it - the minor axis (NA) of the cross-sectional geometry. 5. overhead line mast according to claims 1 to 4, characterized in that two individual masts (1) by means of at least one cross bar (6) are rigidly connected to a frame structure. 6. overhead line mast according to claim 5, characterized in that the distances (a1, a2, a3, a4, a5, a6, a7) between each two adjacent crossbars (6) from the mast start (7) up towards the mast end (8) reduce in harmonic ratio with a factor of preferably between 0.65 and 0.85. 7. overhead line mast according to claims 1 to 6, characterized in that the overhead line mast can be equipped either with brackets (22) for receiving hanging insulators (23) or with directly attached to the overhead line insulator traverses (25). 8. overhead line mast according to claims 1 to 7, characterized in that the wall thickness (3) of the mast cross-sections (Q1, Q2, Q3, Q4, Q5) within a mast segment (2) are constant. 9. overhead line mast according to claims 1 to 8, characterized in that the wall thickness (3) of the individual mast cross-sections (Q1, Q2, Q3, Q4, Q5) locally at least at one point by means of concrete or a concrete-like material (26) a steel-concrete composite cross-section is reinforced. 10. overhead line mast according to claims 1 to 8, characterized in that the wall thickness (3) of the individual mast cross-sections (Q1, Q2, Q3, Q4, Q5) locally at at least one point of the mast cross-section through welded steel profiles (16) or is reinforced by folding profiles (17). 11. Use of the overhead line mast according to at least one of claims 1 to 10 as a radio mast or as a wind mast or advertising mast or as a light mast or as a pillar or as a pylon.