BE1030794B1 - METHOD FOR THERMAL GALVANIZING OF A MANY FENCE PANELS AND GALVANIZED FENCE PANEL - Google Patents

Abstract

The invention concerns a method for thermally galvanizing in a zinc bath a plurality of parallel positioned fencing panels, comprising horizontal and vertical wires, wherein the zinc bath has a depth of at least 1.5 times the height of a fencing panel, and the zinc bath has a length of at least 2.5 times the length of a fencing panel, whereby a zinc layer with a thickness between 50 and 200 mu is deposited on the wires of the fencing panels, and the method includes the steps: (i) immersing the fencing panels in the zinc bath with an incoming downward movement at an angle α; (ii) moving the fencing panels horizontally in the zinc bath, whereby the fencing panels are tilted so that an angle change occurs, and so that the fencing panels are placed at an angle β, where the angles α and β are different; and (iii) withdrawing the fencing panels from the zinc bath with an outward upward movement at the angle β.

Description

1 BE2022/5655

METHOD FOR THERMAL GALVANIZING OF A MANY

FENCE PANELS AND GALVANIZED FENCE PANEL

TECHNICAL DOMAIN

The invention relates to a method for thermal galvanizing of a plurality of fencing panels. In a second aspect, the invention concerns a galvanized fencing panel.

STATE OF THE TECHNOLOGY

Hot dip galvanizing is a commonly used method of galvanizing, intended to protect steel or iron against corrosion. Galvanizing provides a protective layer of zinc that protects the metal against corrosion. If this layer is broken, the zinc acts as a sacrificial anode, so that the iron is protected by the zinc. Hot dip galvanizing is often carried out by immersing metal in a zinc bath with liquid zinc.

Good resistance to corrosion and rust is essential for fencing panels, especially when the fencing panels are intended as an outdoor fence.

Fence panels are manufactured in known methods, such as WO2021165058, by galvanizing the wires of a fencing panel before welding. They are then joined in their perpendicular form by welding horizontal wires to vertical wires. However, the welding process destroys the galvanized coating on the steel in the welded area, leaving the areas where the wires are joined vulnerable to corrosion.

Instead of welding the galvanized wires, non-galvanized wires can also be welded and the entire panel can be galvanized after welding. Galvanizing a complete panel is much more laborious and difficult than galvanizing lengths of wires. Moreover, when galvanizing a panel, some parts of the panel will remain in the zinc bath longer than others, meaning that the zinc layer applied during galvanizing is not uniformly distributed over the fencing panel.

The present invention aims to find a solution for at least some of the above-mentioned problems.

2 BE2022/5655

SUMMARY OF THE INVENTION

The invention concerns a method for thermally galvanizing a plurality of fencing panels according to claim 1. Preferred forms of the method are shown in claims 2 to claim 14. In a second aspect, the invention concerns a galvanized fencing panel according to claim 15.

It is an objective of the invention to make the zinc layer on a fencing panel as uniform as possible. Moreover, the invention is aimed at galvanizing fencing panels as quickly as possible. To this end, it is also an object of the invention to maximize and optimize the dripping of the liquid zinc from the fencing panel.

A further object of the invention is to minimize the web or collar formation on the wires of the fencing panel, and to ensure that the webs or collars only occur in the corner points of the fencing panel. The further aim of the invention is to minimize the thickness of the membranes or collars as much as possible.

The method is advantageous because the method ensures the application of a uniform zinc layer over the entire fencing panel. The method avoids the problems related to variations in the thickness of the zinc layer due to temperature differences in the zinc bath. The method ensures that a uniform zinc layer is obtained with minimal variation due to fleece and collar formation. The change in angle from corner A to corner B minimizes web and collar formation on the wires of the fencing panel. Moreover, the change in angle is also advantageous because the membrane and collar formation only occurs at the intersections in the fencing panel.

Angle B, different from angle a, ensures optimal dripping of the liquid zinc from the fencing panels when pulling the fencing panels out of the zinc bath, which reduces the variation in the thickness of the zinc layer on the fencing panels and increases uniformity. The dimensions of the zinc bath allow entire fencing panels to be galvanized and to be tilted during immersion.

A specific preferred form is shown in claim 6. The speed at which the fencing panels are pulled out of the zinc bath increases as the fencing panels are pulled further out of the zinc bath. The variable and increasing speed ensures a thin zinc layer, with minimal variations in thickness over a fencing panel. This means that the layer thickness differences are maximized as much as possible

3 BE2022/5655 eliminated. Increasing the extraction speed also reduces the sinking time.

The galvanized fencing panel is characterized in that it contains a uniform zinc layer that shows no damage or thinning at the welding points where the wires of the fencing panel are welded together, and also has few webs and/or collars.

DETAILED DESCRIPTION

The invention concerns a method for thermal galvanizing of a plurality of fencing panels.

Unless otherwise defined, all terms used in the description of the invention, including technical and scientific terms, have the meanings commonly understood by those skilled in the art of the invention.

For a better appreciation of the description of the invention, the following terms are explicitly explained. “A”, “the” and “it” in this document refer to both the singular and the plural unless the context clearly suggests otherwise. For example, “a segment” means one or more than one segment.

The terms “comprise”, “comprising”, “providing”, “involving”, “involving”, “containing”, “containing” are synonyms and are inclusive or open terms that indicate the presence of what follows, and that the presence does not exclude or preclude other components, features, elements, members, steps known or described in the prior art.

The terms “consist of”, “consisting of”, “containing”, “containing”, are synonyms and are exclusive or closed terms which indicate the presence of what follows and which exclude or preclude the presence of other components, features, elements , members, steps, known from or described in the prior art.

Quoting numerical intervals through the endpoints includes all integers, fractions, and/or real numbers between the endpoints, including these endpoints.

4 BE2022/5655

In a first aspect, the invention concerns a method for thermally galvanizing in a zinc bath a plurality of parallel positioned fencing panels, comprising horizontal and vertical wires, wherein a zinc layer with a thickness between 50 and 200 mu is deposited on the wires of the fencing panels.

In a preferred embodiment, the zinc bath has a depth of at least 1.5 times the height of a fencing panel, and a length of at least 2.5 times the length of a fencing panel.

In a further preferred embodiment, the method comprises the steps of: i. immersing the fencing panels in the zinc bath with an inward downward movement at an angle a; ii. moving the fencing panels horizontally in the zinc bath, whereby the fencing panels are tilted so that an angle change takes place, and so that the fencing panels are placed at an angle B, whereby the angles a and B are different; and iii. pulling out the fencing panels from the zinc bath with an outward upward movement at angle B.

The method is advantageous because the method ensures the application of a uniform zinc layer over the entire fencing panel. The method avoids the problems related to variations in the thickness of the zinc layer due to temperature differences in the zinc bath. The method ensures that a uniform zinc layer is obtained with minimal variation due to fleece and collar formation. The change in angle from corner A to corner B minimizes web and collar formation on the wires of the fencing panel. Moreover, the change in angle is also advantageous because the membrane and collar formation only occurs at the intersections in the fencing panel.

Angle B, different from angle a, ensures optimal dripping of the liquid zinc from the fencing panels when pulling the fencing panels out of the zinc bath, which reduces the variation in the thickness of the zinc layer on the fencing panels and increases uniformity. The dimensions of the zinc bath allow entire fencing panels to be galvanized and to be tilted during immersion.

In one embodiment, hot-dip galvanizing is applied to a multitude of fencing panels. In a preferred form, between 2 and 100 fencing panels are galvanized at the same time, preferably between 10 and 90, more preferably between 20 and 80, even more preferably between 30 and 70, most preferably between 40 and 60.

In one embodiment, the fencing panel is made of unalloyed steel, low-alloyed steel or high-alloyed steel. The fencing panel can be manufactured from high or low carbon steel. 5 Unalloyed steel contains a maximum of 1.5% alloying elements (excluding carbon (C)). Unalloyed steel has a carbon percentage of 0.5% to 2%. Low-alloy steel contains between 1.5 and 5% alloying elements (excluding carbon). High-alloy steel contains more than 5% alloying elements. The fencing panel is preferably made of unalloyed steel. The term “alloy elements” refers to the elements that are present in the alloy in addition to iron and carbon. In a preferred form, the fencing panel is made of an alloy comprising iron (Fe), carbon (C) and alloying elements. Preferably the alloy comprises a maximum of 1.5% alloying elements, more preferably a maximum of 1.4%, even more preferably a maximum of 1.3%, even more preferably a maximum of 1.2%, most preferably a maximum of 1.1%. Preferably the alloy comprises at least 0.5% alloying elements, more preferably at least 0.6%, even more preferably at least 0.7%, even more preferably at least 0.8%, even more preferably at least 0.9% , most preferably at least 1%. In another preferred form the alloy comprises between 0.5 and 1.5% alloying elements, preferably between 0.6 and 1.5%, more preferably between 0.7 and 1.4%, even more preferably between 0. 8 and 1.3%, even more preferably between 0.9 and 1.2%, most preferably between 1 and 1.1%.

In one embodiment the alloy comprises a maximum of 0.1% C, more preferably a maximum of 0.09%, even more preferably a maximum of 0.085%, even more preferably a maximum of 0.08%, most preferably a maximum of 0.075%. Preferably the alloy comprises at least 0.025% C, more preferably at least 0.03%, even more preferably at least 0.035%, even more preferably at least 0.04%, most preferably at least 0.045%. In another preferred form the alloy comprises between 0.02 and 0.1% C, preferably between 0.025 and 0.09%, more preferably between 0.035 and 0.085%, even more preferably between 0.04 and 0.08% , most preferably between 0.045 and 0.075%.

In a preferred form, the alloy comprises alloying elements selected from the list of: manganese (Mn), silicon (Si), sulfur (S), phosphorus (P), nitrogen (N), copper (Cu), chromium (Cr), nickel ( Ni), niobium (Nb), tin (Sn), aluminum (Al) or any combination of these. Preferably the alloy comprises manganese (Mn), silicon (Si), sulfur (S), phosphorus (P), nitrogen (N), copper (Cu), and optionally chromium (Cr), nickel (Ni), niobium (Nb). ), tin (Sn), aluminum (Al).

6 BE2022/5655

Preferably the alloy comprises Mn in an amount between 0.3 and 0.5%, more preferably between 0.35 and 0.45%, Si in an amount between 0.05 and 0.25%, more preferably between 0.1 and 0.2%, S in an amount between 0.01 and 0.045%, more preferably between 0.015 and 0.04%, P in an amount between 0.005 and 0.03%, more preferably between 0.005 and 0.025%, Cu in an amount between 0.2 and 0.4%, more preferably between 0.25 and 0.35%, N in an amount between 0.005 and 0.02%, more preferably between 0.005 and 0.015% , and Cr in an amount of up to 0.15%, more preferably up to 0.1%, Ni in an amount of up to 0.15%, more preferably up to 0.1%, and Nb in an amount of up to 0.005 %, more preferably a maximum of 0.002%, Sn in an amount of a maximum of 0.05%, more preferably a maximum of 0.03%, and/or Al in an amount of a maximum of 0.005%, more preferably a maximum of 0.003%.

In a preferred form, the fencing panel is a twin-wire or double wire fencing panel. With double wire fencing panels, parallel vertical bars (wires) are welded to horizontal bars (wires), whereby the vertical bars are welded at the same height between two horizontal bars. The fencing panel preferably has between 50 and 55, preferably 51, vertical bars and between 1 and 20 horizontal bars.

In one embodiment, the fencing panels are pre-treated prior to thermal galvanizing. So that the adhesion, integrity and uniformity of the zinc layer is assured.

Preferably, the pre-treatment includes at least one of the following steps: degreasing, rinsing, pickling, fluxing or drying. An example of a pre-treatment is a degreasing with subsequent rinsing, a subsequent acid pickling with subsequent rinsing and finally a fluxing treatment (i.e. a so-called fluxing) with subsequent drying process. Another example of a pretreatment includes the steps of: pickling, rinsing, fluxing and drying.

In one embodiment the vertical wires have a length between 500 and 2500 mm, preferably the vertical wires have a length selected from the list: 606, 608, 630, 806, 808, 830, 1006, 1008, 1030, 1206, 1208, 1230 , 1406, 1408, 1430, 1606, 1608, 1630, 1806, 1808, 1830, 2006, 2008, 2030, 2206, 2208, 2230, 2406, 2408, 2430 mm.

It is clear to the skilled person that the length of the vertical wires corresponds to the height of a fencing panel. In one embodiment the horizontal wires have a length between 2000 and 3000 mm; preferably between 2400 and 2600, even more preferably between 2500 and 2550 mm, most preferably 2508 or 2510 mm. It

7 BE2022/5655 is clear to the professional that the length of the horizontal wires corresponds to the length of a fencing panel.

In a preferred form, the distance between two adjacent vertical wires is 40-60 mm centre-to-centre, more preferably between 45 and 55 mm, even more preferably between 49 and 51, most preferably approximately 50 mm.

In another embodiment, the distance between the adjacent horizontal wires is 100-300 mm centre-to-centre, preferably 150-250 mm, more preferably 180-220 mm, most preferably approximately 200 mm.

The term 'center to center' refers to a distance between the center (the center) of a circular cross-section of a wire and the center (the center) of a circular cross-section of another wire.

In one embodiment, a plurality of parallel positioned fencing panels, comprising horizontal and vertical wires, are thermally galvanized in a zinc bath in the method. The plurality of fencing panels are preferably positioned parallel with a space between them, so that the fencing panels do not touch each other. This avoids contact points that could cause the zinc layer thickness to deviate.

In one embodiment, the fencing panels are positioned parallel and suspended from a suspension device that allows downward and upward movements, so that the fencing panels can be immersed in the suspended condition.

The plurality of fencing panels are immersed (step (i)) in the zinc bath with an inward downward movement at an angle a. The angle a is provided by a tilt in the suspension device. In a preferred form the angle α is at least 5 degrees, preferably at least 10 degrees, more preferably at least 11 degrees, even more preferably at least 12 degrees, most preferably at least 12.5 degrees. In another or further preferred form, the angle α is a maximum of 20 degrees, preferably a maximum of 16 degrees, more preferably a maximum of 15 degrees, even more preferably a maximum of 14 degrees, most preferably a maximum of 13.5 degrees. In another or further preferred form, the angle α is between 5 and 20 degrees, preferably between 10 and 16 degrees, more preferably between 11 and 15 degrees, even more preferably between 12 and 14 degrees, most preferably between 12, 5 and 13.5 degrees.

8 BE2022/5655

Angle a is an angle measured with respect to a horizontal line parallel to the liquid surface.

In a preferred form, the zinc bath has a depth of at least 1.5 times the height of a fencing panel. This depth is necessary so that the fencing panel can be immersed in the zinc bath at an angle a in step (i). In addition, the depth is necessary so that the tilt (angle change) in step (ii) can be carried out without touching the bottom of the zinc bath.

In a preferred form, the depth of the zinc bath is at least 1 m, preferably at least 1.5 m, more preferably at least 2 m, even more preferably at least 2.5 meters, even more preferably at least 3 m, most preferably at least 3.5 m. In another or further preferred form, the depth of the zinc bath is a maximum of 7 m, preferably a maximum of 6.5 m, more preferably a maximum of 6 m, even more preferably a maximum of 5.5 meters, even more preferably maximum 5 m, most preferably maximum 4.5 m. In another or further preferred form, the depth of the zinc bath is 1-7 m, preferably 1.5-6.5 m, more preferably 2-6 m, even more preferably 2.5-5.5 m, even more preferably 3-5 m, most preferably 3.5-4.5 m.

In a preferred form, the zinc bath has a length of at least 2.5 times the length of a fencing panel. This length is necessary so that the fencing panel can be moved horizontally in the zinc bath in step (ii). In addition, the length is necessary so that the tilt (angle change) in step (ii) can be carried out without hitting the sides of the zinc bath.

In a preferred form, the length of the zinc bath is at least 4 m, preferably at least 4.5 m, more preferably at least 5 m, even more preferably at least 5.5 meters, even more preferably at least 6 m, most preferably at least 6.5 m. In another or further preferred form, the length of the zinc bath is a maximum of 10 m, preferably a maximum of 9.5 m, more preferably a maximum of 9 m, even more preferably a maximum of 8.5 meters, even more preferably maximum 8 m, most preferably maximum 7.5 m. In another or further preferred form, the length of the zinc bath is 4-10 m, preferably 4.5-9.5 m, more preferably 5-9 m, even more preferably 5.5-8.5 m, even more preferably 6-8 m, most preferably 6.5-7.5 m.

The zinc bath contains liquid zinc. The zinc bath preferably further comprises at least one of the following components: lead (Pb), nickel (Ni), aluminum (Al), or a combination of these.

9 BE2022/5655

In one embodiment, the zinc bath comprises a combination of zinc, lead, nickel and aluminum. In a further embodiment, the zinc bath comprises: - zinc, in an amount between 95 and 99 m% of the total zinc bath; - Iodine, in an amount of a maximum of 5 m% of the total zinc bath, preferably a maximum of 2 m% of the total zinc bath, more preferably a maximum of 1 m% of the total zinc bath; - nickel, in an amount of a maximum of 1 M% of the total zinc bath, preferably a maximum of 0.1 m% of the total zinc bath, more preferably a maximum of 0.05 m% of the total zinc bath; - aluminium, in an amount of a maximum of 0.01 m% of the total zinc bath, preferably a maximum of 0.001 m% of the total zinc bath, more preferably a maximum of 0.0007 m% of the total zinc bath.

In step (ii) the plurality of suspended fencing panels are moved horizontally through the zinc bath. The fencing panels are tilted so that an angle change takes place, and so that the fencing panels are placed at an angle B, where the angles a and B are different.

In a preferred form, the plurality of fencing panels are tilted in step (ii), whereby a first angle change takes place, whereby the fencing panels are tilted to a substantially horizontal position. This tilting can take place before or during the horizontal movement through the zinc bath in step (ii), preferably during the horizontal movement. In a further preferred form, the plurality of fencing panels are then tilted again, whereby a second angle change takes place, whereby the fencing panels are tilted to an angle B. This second tilting can take place during or after the horizontal movement through the zinc bath in step (ii), preferably during the horizontal movement.

When the fencing panels are immersed, the zinc in the zinc bath cools locally. This causes non-uniformity in the zinc layer because more zinc is deposited on the fencing panel at a higher temperature than at a lower temperature. The horizontal movement in the zinc bath ensures that the fencing panels are moved to a warmer part of the zinc bath, which improves the uniformity of the zinc layer on the wires of the fencing panel.

In a particularly preferred form, the angle a is adjusted in step (ii) to an angle of approximately 0°C and then to an angle B.

10 BE2022/5655

The plurality of fencing panels are pulled out of the zinc bath in step (iii) with an outward upward movement under an angle B. The angle B is provided by a tilt in the hanging device. The angle B preferably has a sign equal to that of angle a. In a preferred form, the angle B is at least 25 degrees, preferably at least 30 degrees, more preferably at least 31 degrees, even more preferably at least 32 degrees, even more preferably at least 33 degrees, most preferably at least 35.5 degrees. In another or further preferred form, the angle B is a maximum of 45 degrees, preferably a maximum of 40 degrees, more preferably a maximum of 39 degrees, even more preferably a maximum of 38 degrees, even more preferably a maximum of 37 degrees, most preferably a maximum of 36.5 degrees. In another or further preferred form, the angle B is between 25 and 45 degrees, preferably between 30 and 40 degrees, more preferably between 31 and 39 degrees, even more preferably between 32 and 38 degrees, even more preferably between 33 and 37 degrees, most preferably between 35.5 and 36.5 degrees.

Angle B is an angle measured with respect to a horizontal line parallel to the liquid surface.

In a preferred form, the extraction speed at which the plurality of fencing panels are pulled out of the zinc bath in step (iii) is between 0.1 and 5 m/min, preferably between 0.1 and 2 m/min, more preferably between 0. 4 and 1.55 m/min. In another or further preferred form, the extraction speed at which the plurality of fencing panels are pulled out of the zinc bath in step (iii) is constant or increasing, preferably the extraction speed is increasing during extraction. This means that the speed increases the further the fencing panel is pulled out of the zinc bath. Preferably, the extraction speed increases in steps.

In a preferred form, the extraction speed at which the plurality of fencing panels are withdrawn from the zinc bath in step (iii) is increasing in the range of 0.1 to 5 m/min, preferably in the range of 0.1 to 2 m/min , more preferably in the range of 0.4 to 1.55 m/min.

The speed at which the fencing panels are pulled out of the zinc bath increases as the fencing panels are pulled further out of the zinc bath. The variable and increasing speed ensures a thin zinc layer, with minimal variations in thickness over a fencing panel.

11 BE2022/5655

When the fencing panels are pulled out of the zinc bath, the air mass above the zinc bath becomes warmer. The warm air mass also has an influence on the zinc layer. It has been found that increasing the extraction speed minimizes this influence.

In a preferred form, the method further comprises the step (iv) of moving air lances between the wires of the fencing panels, wherein the air lances blow air under increased pressure between the wires of the plurality of fencing panels.

The air lances blow air under pressure through the openings of the fencing panels.

Openings are intended to be the grids formed by the horizontal and vertical wires in a fencing panel. As a result, the extraction speed in step (iii) may be higher because so-called 'fleeces' of liquid zinc that are formed in the openings when pulling out the fencing panels from the zinc bath and the dripping of the liquid zinc from the fencing panels during extraction are blown away or be blown to pieces.

The air lances move through the openings of the multitude of fencing panels during blowing, so that any membranes formed on each fencing panel can be blown apart. In one embodiment, the air lances are movable so that they can move through the plurality of fencing panels during blowing. In one embodiment, air lances are moved through all openings simultaneously. In another preferred form, the air lances are moved simultaneously through the openings at the same horizontal height, after which the air lances are then moved simultaneously through the openings at a next equal horizontal height.

In a preferred form, the air lances move at a speed between 5 and 40 m/min, preferably between 10 and 35 m/min.

In a preferred form, the air blown from the air lances has a pressure between 2 and 10 bar, preferably between 3 and 7 bar, more preferably between 4 and 6 bar.

In a preferred form, the air is blown from the air lances at a flow rate between 500 and 1500 m3/hour, preferably between 750 and 1250 m3/hour, more preferably between 850 and 1150 m3/hour, even more preferably between 950 and 1050 m3/hour.

12 BE2022/5655

In a preferred form, the air lances move in a first direction perpendicular to the wires of the fencing panels in the plurality of fencing panels, preferably at a speed between 5 and 25 m/min, and then back out of the fencing in a second direction opposite to the first direction. multiple fencing panels move, preferably at a speed between 20 and 40 m/min.

In a further preferred form, the speed in the first direction is between 10 and 20 m/min, preferably between 11 and 18 m/min, more preferably between 12 and 17 m/min, even more preferably between 13 and 15 m /min.

In another further preferred form, the speed in the second direction is between 25 and 35 m/min, preferably between 26 and 34 m/min, more preferably between 27 and 33 m/min, even more preferably between 28 and 32 m/min, most preferably between 29 and 31 m/min.

In one embodiment, the zinc layer deposited on the wires of the fencing panels has a thickness between 50 and 200 mu.

The average layer thickness on the fencing panel preferably complies with the ISO 1461 standard.

In a preferred form, the average zinc layer on the wires of the fencing panels is between 40 and 120 mu. In a further preferred form, the average thickness of the zinc layer on the wires of the fencing panels is between 60 and 80 mu.

The zinc layer and the average zinc layer on the fencing panel can be measured using a gravimetric measurement in accordance with EN ISO 1460 or a magnetic method in accordance with EN ISO 2178.

In a second aspect, the invention concerns a galvanized fencing panel comprising vertical and horizontal wires.

The galvanized fencing panel is advantageous because it contains a thin zinc layer that shows no damage or thinning at the welding points where the wires of the fencing panel are welded together.

13 BE2022/5655

In a preferred embodiment, a zinc layer with a thickness between 50 and 200 mu is attached to the wires of the fencing panel.

In a preferred form, the average zinc layer on the wires of the fencing panels is between 40 and 120 mu. In a further preferred form, the average thickness of the zinc layer on the wires of the fencing panels is between 60 and 80 mu.

In a preferred form, the galvanized fencing panel is obtained according to a method according to the first aspect of the invention.

In what follows, the invention is described by means of: non-limiting examples and figures illustrating the invention, and which are not intended or should be construed to limit the scope of the invention.

EXAMPLES AND FIGURE DESCRIPTION

Figure 1 shows step (i) of a method according to the first aspect.

In step (i) of the method, a plurality of fencing panels (5), comprising vertical (1) and horizontal (2), wires are immersed (i) in a zinc bath. The plurality of fencing panels are suspended from a suspension device (4) that engages in a suspension point (7) at an angle a. The angle a is an angle measured with respect to a horizontal line (6) through the suspension point (7) parallel to the liquid surface. (3) in the zinc bath.

Figure 2 shows step (iii) of a method according to the first aspect.

In step (iii) of the method, a plurality of fencing panels (5), comprising vertical (1) and horizontal (2), wires are pulled from the zinc bath (iii). The plurality of fencing panels are suspended from a suspension device (4) that engages in a suspension point (7) at an angle B. The angle B is an angle measured with respect to a horizontal line (6) through the suspension point (7) parallel to the liquid surface (3) in the zinc bath.

Figure 3 shows a schematic representation of a method according to the first aspect.

The plurality of fencing panels are immersed in the zinc bath at an angle a of 13 degrees. Once the fencing panels have been immersed in the zinc bath, the fencing panels are tilted during a horizontal movement in the zinc bath to an angle of approximately 0 degrees, after which the fencing panels are lowered using a second

14 BE2022/5655 angle change can be tilted to an angle B of 36 degrees. The fencing panels are then pulled back out of the zinc bath at an angle B of 36 degrees.

Figure 4 shows the gradually increasing extraction speeds (201) in m/min as a function of the position relative to the liquid surface (202) for examples 1, 2 and 3, where 5550 is the starting position of the extraction at the liquid surface.

Examples 1, 2 and 3 concern gradually increasing extraction speeds in meters per minute (m/min) for three different fencing panels.

Example 1 concerns the extraction of a multitude of twin-wire fencing panels with a height between 1430 and 2430 mm. The vertical and horizontal wires have a diameter of 6 and 8 mm respectively. Example 2 concerns the extraction of a multitude of twin-wire fencing panels with a height between 600 and 1230 mm. The vertical and horizontal wires have a diameter of 6 and 8 mm respectively.

Example 3 concerns the extraction of a multitude of twin-wire fencing panels with a height between 600 and 2430 mm. The vertical and horizontal wires have a diameter of 5 and 6 mm respectively. The pull-out speeds are shown in Table 1 and Figure 4.

TABLE 1 position | speed (m/min) | Position | speed (m/min) | Position | speed (m/min) 2300 os [mo [EE ai a CE [EE mie [9 [E&

Figure 5 and figure 6 show a double wire fencing panel that can be galvanized according to the method of the first aspect. Figure 5 shows a perspective

15 BE2022/5655 view of a double-wire fencing panel. Figure 6 shows an enlarged perspective view of a double wire fencing panel (section A in Figure 5).

A double wire fencing panel (108) consists of parallel vertical wires (104) welded to horizontal wires (101, 102) with the vertical wires welded at each height between two horizontal wires (101, 102), which together form a double pair (103) . The distance between two adjacent vertical wires (106) is approximately 50 mm center to center. The distance between the adjacent horizontal wires (105) is approximately 200 mm center to center.

Claims (15)

16 BE2022/5655 CONCLUSIONS 1. A method for thermally galvanizing in a zinc bath a plurality of parallel positioned fencing panels, comprising horizontal and vertical wires, wherein the zinc bath has a depth of at least 1.5 times the height of a fencing panel, and wherein the zinc bath has a length of at least 2.5 times the length of a fencing panel, whereby a zinc layer with a thickness between 50 and 200 mu is deposited on the wires of the fencing panels, and where the method comprises the steps of: i. immersing the fencing panels in the zinc bath with an inward downward movement at an angle a, where angle a is measured with respect to a horizontal line parallel to the liquid surface; il. the horizontal movement of the fencing panels in the zinc bath, whereby the fencing panels are tilted so that an angle change takes place, and so that the fencing panels are placed at an angle ß, where the angles a and ß are different, and where angle B is measured with respect to a horizontal line parallel to the liquid surface; and iii. pulling out the fencing panels from the zinc bath with an outward upward movement at angle B. 2. Method according to claim 1, wherein the plurality of fencing panels are tilted in step (ii), wherein a first and a second angle change takes place, wherein the fencing panels are tilted in a first angle change from an angle α to a substantially horizontal position, and wherein the fencing panels are tilted in a second angle change from a mainly horizontal position to an angle B. Method according to claim 1 or 2, wherein the angle a is between 5 and 20 degrees, preferably between 10 and 16 degrees. Method according to any of the preceding claims, wherein the angle B is between 25 and 45 degrees, preferably between 30 and 40 degrees. 5. Method according to any of the preceding claims, wherein the extraction speed at which the plurality of fencing panels are pulled out of the zinc bath is in step 17 BE2022/5655 (iii), is between 0.1 and 5 m/min, preferably between 0.1 and 2 m/min, more preferably between 0.4 and 1.55 m/min. 6. Method according to any of the preceding claims, wherein the extraction speed at which the plurality of fencing panels are pulled out of the zinc bath in step (iii) is constant or increasing, preferably the extraction speed is increasing during extraction. Method according to any one of the preceding claims, wherein the extraction speed at which the plurality of fencing panels are pulled out of the zinc bath in step (iii) is increasing in the range of 0.1 to 5 m/min, preferably in the range of 0 .1 to 2 m/min, more preferably in the range of 0.4 to 1.55 m/min. 8. Method according to any of the preceding claims, wherein the extraction speed at which the plurality of fencing panels are pulled out of the zinc bath in step (iii) increases gradually. A method according to any one of the preceding claims, wherein the method further comprises the step (iv) of moving air lances between the wires of the fencing panels, wherein the air lances blow air under increased pressure between the wires of the plurality of fencing panels. Method according to claim 9, wherein the air lances move at a speed between 5 and 40 m/min, preferably between 10 and 35 m/min. Method according to any one of claims 9-10, wherein the air blown from the air lances has a pressure between 2 and 10 bar, preferably between 3 and 7 bar, more preferably between 4 and 6 bar. A method according to any one of claims 9-11, wherein the air is blown from the air lances at a flow rate between 500 and 1500 m3/hour, preferably between 750 and 1250 m3/hour. A method according to any one of claims 9-12, wherein the air lances move in a first direction perpendicular to the wires of the fencing panels in the plurality of fencing panels, preferably at a speed between 5 and 25 m/min, and then in a second direction opposite to the first 18 BE2022/5655 back from the multitude of fencing panels, preferably at a speed between 20 and 40 m/min. 14. Method according to any of the preceding claims, wherein the average zinc layer on the wires of the fencing panels is between 60 and 80 mu, measured according to a gravimetric measurement in accordance with EN ISO 1460. 15. A galvanized fencing panel comprising vertical and horizontal wires, characterized in that a zinc layer with a thickness between 50 and 200 mu is attached to the wires of the fencing panel, measured according to a gravimetric measurement in accordance with EN ISO 1460.