A method for zinc-coating a welded joint of a zinc-coated steel material

Abstract

This invention discloses a method for zinc-clad steel welded joints, belonging to the field of welding technology. To address the problems of poor adhesion, easy aging, incomplete protection, and low durability associated with traditional methods such as applying anti-corrosion coatings, wrapping with heat-shrink tubing, or using tape for corrosion protection of welded joints, this invention provides a method for zinc-clad steel welded joints. The method comprises the following steps: S1, Mold installation: Pre-fabricate a mold according to the shape and size of the zinc-clad steel welded joint, and then fit the pre-fabricated mold onto the welded joint; S2, Melting zinc granules: Place an appropriate amount of zinc granules into a crucible and heat it to a temperature controlled between 419.5℃ and 500℃ until it melts; S3, Casting and coating: Pour the molten zinc into the pre-fabricated mold, ensuring the zinc fully coats the welded joint and the main material. After cooling, a closed zinc layer is formed, seamlessly bonded to the original zinc-clad steel layer. By coating the welded joint with a zinc layer, the entire zinc-clad steel system forms a closed zinc layer protection, thereby extending its service life.

Description

Technical Field

[0001] This invention belongs to the field of welding technology, and specifically relates to a method for zinc cladding of welded joints of zinc-clad steel materials. Background Technology

[0002] In grounding and cathodic protection engineering, zinc-clad steel is commonly used as the primary material for sacrificial anodes and corrosion-resistant grounding. Zinc-clad steel connections are typically made using electric welding or exothermic welding. However, during welding, the zinc layer at the joint is damaged, exposing the steel substrate to direct contact with corrosive media in the environment (such as moisture, oxygen, and salt), leading to accelerated localized corrosion and making the welded joint a weak point in the entire system. This not only shortens the system's service life but may also cause electrical faults, grounding failures, and other safety accidents. Current technologies for corrosion protection of welded joints often employ methods such as applying anti-corrosion coatings, wrapping with heat-shrink tubing, or using adhesive tape. However, these methods suffer from poor adhesion, easy aging, incomplete protection, and low durability. Summary of the Invention

[0003] The purpose of this invention is to solve the problems of poor adhesion, easy aging, incomplete protection, and low durability of corrosion protection methods such as coating anti-corrosion paint, wrapping heat shrink tubing, or using tape for welded joints. This invention provides a zinc-coating method for welded joints of zinc-clad steel materials. By coating the welded joint with a zinc layer, the entire zinc-clad steel system forms a closed zinc layer protection, thereby extending its service life and preventing accidents.

[0004] To achieve the above objectives, the present invention employs the following technical solution:

[0005] A zinc-clad steel welded joint zinc coating method, the method relying on a zinc-clad steel welded joint mold, the mold comprising two symmetrically arranged mold bodies connected by snap-fit, the upper part of the mold body being provided with a pouring port and an venting port;

[0006] The method steps are as follows:

[0007] S1. Install mold: Pre-fabricate molds according to the shape and size of the zinc-clad steel welding joint, and fit the pre-fabricated molds onto the welding joint so that the molds can completely cover the welding joint and the adjacent main material parts;

[0008] S2. Molten zinc granules: Place an appropriate amount of zinc granules into a crucible and heat the crucible at a temperature between 419.5℃ and 500℃ until it melts.

[0009] S3. Casting Coating: Molten zinc liquid is poured into a precast mold to fully coat the welded joint and main material. After cooling, a closed zinc layer is formed, which is seamlessly bonded to the original zinc-clad steel layer.

[0010] Furthermore, the mold is made of high-temperature resistant materials such as graphite, steel, or ceramic.

[0011] Furthermore, the purity of the zinc granules is greater than 99.9%.

[0012] The beneficial effects of this invention are:

[0013] 1. This invention achieves full coverage of the welded joint through prefabrication and casting methods, forming a continuous and closed zinc layer to avoid localized corrosion.

[0014] 2. The zinc layer of the present invention is firmly bonded to the substrate, has good durability, and is suitable for harsh environments.

[0015] 3. The method of the present invention is simple, low in cost, easy to carry out on-site construction, and improves project efficiency. Attached Figure Description

[0016] Figure 1 This is a flowchart of a method for zinc-clad steel welded joints. Detailed Implementation

[0017] To make the objectives, technical solutions, and advantages of this invention clearer, the invention is described below with reference to specific embodiments shown in the accompanying drawings. However, it should be understood that these descriptions are merely exemplary and not intended to limit the scope of the invention. Furthermore, descriptions of well-known structures and technologies are omitted in the following description to avoid unnecessarily obscuring the concept of the invention.

[0018] Example 1:

[0019] A zinc-clad steel welded joint zinc coating method, the method relying on a zinc-clad steel welded joint mold, the mold comprising two symmetrically arranged mold bodies connected by snap-fit, the upper part of the mold body being provided with a pouring port and an venting port;

[0020] The method steps are as follows:

[0021] S1. Install mold: Pre-fabricate molds according to the shape and size of the zinc-clad steel welding joint, and fit the pre-fabricated molds onto the welding joint so that the molds can completely cover the welding joint and the adjacent main material parts;

[0022] S2. Molten zinc granules: Place an appropriate amount of zinc granules into a crucible and heat it to 419.5℃ to melt it;

[0023] S3. Casting Coating: Molten zinc liquid is poured into a precast mold to fully coat the welded joint and main material. After cooling, a closed zinc layer is formed, which is seamlessly bonded to the original zinc-clad steel layer.

[0024] Specifically, the mold is made of high-temperature resistant materials such as graphite, steel, or ceramic.

[0025] Specifically, the purity of the zinc granules is greater than 99.9%.

[0026] Specifically, after the coating is completed, the zinc layer surface can be lightly polished to remove burrs or uneven areas.

[0027] Example 2:

[0028] The steps are the same as in Example 1, except that in step S2, melting zinc granules: take an appropriate amount of zinc granules and put them into a crucible, and heat them to 450°C to melt them.

[0029] Example 3:

[0030] The steps are the same as in Example 1, wherein step S2, melting zinc granules: take an appropriate amount of zinc granules and put them into a crucible, and heat them to 500°C to melt them.

[0031] The present invention has been described in detail above. However, modifications or improvements can be made to it, which will be obvious to those skilled in the art. Therefore, any modifications or improvements that do not depart from the spirit of the present invention are within the scope of protection of the present invention.

Claims

1. A method for zinc cladding of a zinc-clad steel welded joint, the method relying on a mold for a zinc-clad steel welded joint, the mold comprising two symmetrically arranged mold bodies connected by snap-fit, the upper part of the mold body being provided with a pouring port and an venting port; Its features are: The method steps are as follows: S1. Install mold: Pre-fabricate molds according to the shape and size of the zinc-clad steel welding joint, and fit the pre-fabricated molds onto the welding joint so that the molds can completely cover the welding joint and the adjacent main material parts; S2. Molten zinc granules: Place an appropriate amount of zinc granules into a crucible and heat the crucible at a temperature between 419.5℃ and 500℃ until it melts. S3. Casting Coating: Molten zinc liquid is poured into a precast mold to fully coat the welded joint and main material. After cooling, a closed zinc layer is formed, which is seamlessly bonded to the original zinc-clad steel layer.

2. The method for zinc cladding of welded joints of zinc-clad steel materials according to claim 1, characterized in that: The mold is made of high-temperature resistant materials such as graphite, steel, or ceramic.

3. The method for zinc cladding of welded joints of zinc-clad steel materials according to claim 2, characterized in that: The zinc granules have a purity greater than 99.9%.

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