A desulfurization system outboard pipe hull plate anticorrosion device

Abstract

The utility model relates to ship body anticorrosive technical field especially a kind of desulfurization system outboard pipe ship shell plate anticorrosive device, including ship shell plate, further including super duplex stainless steel outboard pipe, the super duplex stainless steel outboard pipe is fixedly welded on the ship shell plate, for discharging desulfurization washing water;Super duplex stainless steel double plate, the super duplex stainless steel double plate is circular ring plate, it is set in the outer periphery of the super duplex stainless steel outboard pipe and coaxially arranged;The inner ring edge of the super duplex stainless steel double plate is fixedly connected with the outer wall of the super duplex stainless steel outboard pipe, the utility model isolates acidic washing water and carbon steel ship shell plate, solve the problem of the quick corrosion of ship shell plate due to contact scouring, circular ring double plate and outboard pipe coaxial matching, can evenly cover and protect entire high corrosion risk area, effectively prevent corrosion from spreading around, significantly prolong the service life of ship shell plate at outboard pipe.

Description

Technical Field

[0001] This utility model relates to the field of ship hull corrosion protection technology, and in particular to a corrosion protection device for the outer pipe of a desulfurization system on the ship hull plate. Background Technology

[0002] Currently, during the retrofitting of ship desulfurization systems, the hull plates of the desulfurization tower wash water discharge pipes are made of carbon steel plates, which are treated with anti-corrosion paint. However, ship desulfurization involves cleaning diesel engine exhaust gas through the desulfurization device. The wash water after cleaning is a strongly acidic solution with a pH of 1-3, which is highly corrosive. The wash water discharged through the discharge pipes comes into prolonged contact with the hull plates at the outlet of the discharge pipes, causing corrosion and erosion. This results in accelerated corrosion of the hull plates at the desulfurization tower discharge pipes during ship navigation. Consequently, ships have to suspend normal operations and undergo hull plate replacement at the shipyard due to hull corrosion near the discharge pipes, which increases maintenance costs and also raises the ship's operating costs.

[0003] To address these issues, those skilled in the art have proposed an anti-corrosion device for the hull plates of the desulfurization system's outer pipes. Utility Model Content

[0004] The purpose of this section is to outline some aspects of embodiments of the present invention and to briefly describe some preferred embodiments. Simplifications or omissions may be made in this section, as well as in the abstract and title of this application, to avoid obscuring the purpose of these documents; however, such simplifications or omissions should not be construed as limiting the scope of the present invention.

[0005] In view of the problem that accelerated corrosion often occurs on the hull plates at the outer pipe of the desulfurization tower in the above or existing technologies, this utility model is proposed.

[0006] Therefore, the purpose of this utility model is to provide a corrosion protection device for the hull plate of the desulfurization system's outer pipe.

[0007] To solve the above-mentioned technical problems, this utility model provides the following technical solution: a corrosion protection device for the hull plate of a desulfurization system's outer pipe, comprising a hull plate, and further comprising: A super duplex stainless steel outboard tube, which is inserted through and welded to the hull plate, is used to discharge desulfurization washing water. Super duplex stainless steel cladding plate, wherein the super duplex stainless steel cladding plate is a circular ring plate, which is sleeved on the outer periphery of the super duplex stainless steel overboard tube and arranged coaxially. The inner ring edge of the super duplex stainless steel cladding plate is welded to the outer wall of the super duplex stainless steel outboard tube, and its outer ring edge is welded to the surface of the hull plate. Multiple plug weld holes are provided between the inner and outer ring edges of the super duplex stainless steel cladding plate, and the cladding plate is fixed to the hull plate by plug welding through the plug weld holes. The welds between the super duplex stainless steel cladding plate, the hull plate, and the super duplex stainless steel outboard tube form a continuous sealing structure.

[0008] As a preferred embodiment of the anti-corrosion device for the outer pipe of the desulfurization system of this utility model, the material of the super duplex stainless steel cladding plate is any one of SS25073, SS22059 or SMO254.

[0009] As a preferred embodiment of the anti-corrosion device for the outer pipe of the desulfurization system of this utility model, the thickness of the super duplex stainless steel composite plate is 3-5mm, preferably 5mm.

[0010] As a preferred embodiment of the anti-corrosion device for the hull plate of the desulfurization system outboard pipe of this utility model, wherein: the outer diameter of the super duplex stainless steel cladding plate is not less than 3 times the outer diameter of the super duplex stainless steel outboard pipe, and the inner diameter of the super duplex stainless steel cladding plate is equal to the outer diameter of the super duplex stainless steel outboard pipe plus 20mm.

[0011] As a preferred embodiment of the anti-corrosion device for the outer pipe of the desulfurization system of this utility model, wherein: the plug welding hole is a slotted hole, which is evenly arranged along the circumferential direction of the super duplex stainless steel composite plate.

[0012] As a preferred embodiment of the anti-corrosion device for the outer pipe of the desulfurization system of this utility model, the super duplex stainless steel composite plate is composed of two semi-circular ring plates spliced ​​together.

[0013] As a preferred embodiment of the anti-corrosion device for the outer pipe of the desulfurization system of this utility model, wherein: a corrosion-resistant metal layer is overlaid at the connection between the super duplex stainless steel composite plate and the hull plate and the super duplex stainless steel outer pipe.

[0014] As a preferred embodiment of the anti-corrosion device for the outer pipe of the desulfurization system of this utility model, the end of the super duplex stainless steel outer pipe protrudes 14-20mm from the outer surface of the hull plate, and the super duplex stainless steel cladding plate covers the protrusion and is welded to the protrusion to form a smooth transition flow guiding surface.

[0015] The beneficial effects of this utility model on the anti-corrosion device for the outer pipe of a desulfurization system hull plate: The system incorporates super duplex stainless steel cladding plates and super duplex stainless steel outboard tubes. The inner and outer ring edges of the super duplex stainless steel cladding plates are welded and sealed to the outer wall of the super duplex stainless steel outboard tubes and the hull plates, forming a physical protection against strong acid corrosion. This isolates the acidic washing water from the carbon steel hull plates, solving the problem of rapid corrosion of the hull plates caused by contact erosion. The annular cladding plates are coaxially matched with the outboard tubes, which can evenly cover and protect the entire high-corrosion-risk area, effectively preventing corrosion from spreading to the surrounding areas and significantly extending the service life of the hull plates at the outboard tubes. The plug-welded holes on the annular plate enhance the connection strength and fit with the hull plate, ensuring the long-term stability and reliability of the protective barrier. The smooth flow guiding surface reduces fluid resistance and turbulent erosion, further improving the durability of the device, reducing the need for frequent dry-docking maintenance due to hull plate corrosion, and saving costs. Attached Figure Description

[0016] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. Among them: Figure 1 A front view structural diagram of the super duplex stainless steel composite plate used as an anti-corrosion device for the outer pipe of the desulfurization system.

[0017] Figure 2 This is a side sectional schematic diagram of the anti-corrosion device for the outer pipe of the desulfurization system on the ship's hull.

[0018] Figure 3 for Figure 2 A partially enlarged structural diagram. Detailed Implementation

[0019] To make the above-mentioned objectives, features and advantages of this utility model more apparent and understandable, the specific embodiments of this utility model will be described in detail below with reference to the accompanying drawings.

[0020] Many specific details are set forth in the following description in order to provide a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Those skilled in the art can make similar extensions without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0021] Secondly, the term "an embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in different places in this specification does not necessarily refer to the same embodiment, nor is it a single or selective embodiment that excludes other embodiments.

[0022] Reference Figures 1 to 3 This embodiment provides a corrosion protection device for the hull plate of a desulfurization system's outer pipe, which can achieve the effect of isolating acidic washing water from the carbon steel hull plate. It includes hull plate 2, and further includes: Super duplex stainless steel outboard tube 1, which is inserted through and welded to the hull plate 2, is used to discharge desulfurization washing water. Super duplex stainless steel composite plate 3, which is a circular plate, is fitted around the outer periphery of the super duplex stainless steel overboard tube 1 and arranged coaxially. The inner ring edge of the super duplex stainless steel cladding plate 3 is welded to the outer wall of the super duplex stainless steel overboard tube 1, and its outer ring edge is welded to the surface of the hull plate 2. Multiple plug welding holes are opened between the inner and outer ring edges of the super duplex stainless steel cladding plate 3. The cladding plate 3 is fixed to the hull plate 2 by plug welding through the plug welding holes. The welds between the super duplex stainless steel cladding plate 3, the hull plate 2, and the super duplex stainless steel overboard tube 1 form a continuous sealing structure.

[0023] The hull plate 2 refers to the hull plate in the area where the super duplex stainless steel outboard tube 1 is installed. Its function is to work together with the super duplex stainless steel outboard tube 1 to ensure the watertightness of the hull, so that the ship has the ability to float and carry cargo.

[0024] The excellent corrosion resistance of super duplex stainless steel composite plate 3 is used to prevent corrosion of the hull plate 2 at the outer pipes caused by the discharge of acidic wash water from the ship's desulfurization system.

[0025] The function of the super duplex stainless steel outboard tube 1 is to discharge acidic desulfurization washing water into the sea. It needs to be welded to the hull plate 2 and form a watertight structure with the hull. It is manufactured according to the dimensions specified in the drawings and meets the requirements of Class II pressure pipeline specified in GB / T 31928-2015 Stainless Steel Seamless Pipes for Ships.

[0026] Specifically, the material of the super duplex stainless steel composite plate 3 is any one of SS25073, SS22059 or SMO254.

[0027] Super duplex stainless steel plate 3 has superior corrosion resistance. Its high chromium, molybdenum and nitrogen content gives it excellent resistance to pitting corrosion, crevice corrosion and stress corrosion cracking in chloride-containing environments such as seawater and chemical media. Its corrosion resistance is superior to that of ordinary austenitic stainless steel.

[0028] Furthermore, the thickness of the super duplex stainless steel composite plate 3 is 3-5mm.

[0029] The hull plate 2 needs to be welded to the super duplex stainless steel cladding plate 3. Therefore, the hull plate 2 in the welding area needs to be cleaned of surface contaminants such as grease, coatings and oxide films to improve the welding quality.

[0030] Among them, the outer diameter of the super duplex stainless steel cladding plate 3 is not less than 3 times the outer diameter of the super duplex stainless steel outer tube 1, and the inner diameter of the super duplex stainless steel cladding plate 3 is equal to the outer diameter of the super duplex stainless steel outer tube 1 plus 20mm.

[0031] The super duplex stainless steel outboard tube 1 is a tubular component welded onto the hull plate 2 and together with the hull plate 2 forms a watertight structure for the hull. Its function is to discharge acidic desulfurization washing water into the sea. At the same time, the super duplex stainless steel outboard tube 1 needs to be welded to the super duplex stainless steel cladding plate 3. The circumferential joint between the super duplex stainless steel cladding plate 3 and the super duplex stainless steel outboard tube 1 is filled with fillet welds with a weld thickness of 5mm. The weld fills and covers the circumferential joint.

[0032] Among them, the plug welding holes are slotted holes 4, which are evenly arranged along the circumference of the super duplex stainless steel composite plate 3.

[0033] Among them, the super duplex stainless steel composite plate 3 is made up of two semi-circular ring plates spliced ​​together.

[0034] Furthermore, a corrosion-resistant metal layer is welded over the connection between the super duplex stainless steel composite plate 3, the hull plate 2, and the super duplex stainless steel outer tube 1.

[0035] The hull plate 2 at the super duplex stainless steel outer tube 1 is protected from corrosion by a corrosion-resistant metal overlay.

[0036] It should be noted that the end of the super duplex stainless steel outboard tube 1 protrudes 14-20mm beyond the outer surface of the hull plate 2. The super duplex stainless steel cladding plate 3 covers the protrusion and is welded to the protrusion to form a smooth transition flow guide surface.

[0037] The smooth flow guide surface reduces fluid resistance and turbulent erosion, further improving the durability of the device.

[0038] Working Principle: During use, welding is performed according to the dimensions of the outer pipe in the detailed installation drawings of the desulfurization tower system. For ease of explanation, taking a pipe diameter of φ355mm and a material of S32750 for the super duplex stainless steel outer pipe 1 as an example, the specifications of the super duplex stainless steel cladding plate 3 are determined as follows: the outer diameter of the super duplex stainless steel cladding plate 3 is not less than 3 times the outer diameter of the super duplex stainless steel outer pipe 1, and the inner diameter is the outer diameter of the super duplex stainless steel outer pipe 1 + 20mm. That is, the outer diameter of the super duplex stainless steel cladding plate 3 is φ1065mm, the inner diameter is φ375mm, and the thickness is 5mm. The super duplex stainless steel composite plate 3 is prefabricated according to the drawings of the composite plate parts. A slotted hole 4 is required in the center between the inner and outer circles. The size of the slotted hole 4 is 20mm*10mm, and the quantity is 10pcs. The slotted hole 4 needs to be welded to the hull plate 2. All of them are fully welded with welding wire and are at least flush with the surface of the super duplex stainless steel composite plate 3 to ensure the stability of the connection between the super duplex stainless steel composite plate 3 and the hull plate 2, thereby strengthening the reliable connection between the super duplex stainless steel composite plate 3 and the hull plate 2. At the same time, the super duplex stainless steel composite plate 3 needs to be made into a spliced ​​type, that is, two half-circular plates, to facilitate on-site installation and welding operations.

[0039] Based on the detailed installation drawings of the super duplex stainless steel outer pipe 1 and the part drawings of the super duplex stainless steel cladding plate 3 of the desulfurization tower system, the installation node diagram of the super duplex stainless steel cladding plate 3 is drawn. Although the super duplex stainless steel has good weldability, it is necessary to follow strict welding procedures, control heat input and interpass temperature to maintain the balance of austenite and ferrite and avoid the precipitation of harmful intermetallic phases. The welding of the super duplex stainless steel cladding plate 3 and the carbon steel hull plate 2 is a dissimilar steel welding, and the weld is prone to cracking. Before welding, it is necessary to remove grease, coating and oxide film contaminants from the surface of the hull plate 2. Tungsten inert gas welding is used throughout the process. After the welding is completed, the weld needs to be subjected to non-destructive testing. Defects such as cracks, porosity and inclusions are not allowed.

[0040] For onboard installation, the super duplex stainless steel outboard tube 1 needs to protrude 14-20mm from the end of the hull plate 2. After the super duplex stainless steel outboard tube 1 is welded to the hull plate 2, the super duplex stainless steel cladding plate 3 is installed coaxially with the super duplex stainless steel outboard tube 1 on the outer wall of the hull according to the cladding plate installation node diagram. Fillet welds are added at the circumferential joint between the super duplex stainless steel cladding plate 3 and the super duplex stainless steel outboard tube 1, with a weld thickness of 5mm. The weld fills and covers the circumferential joint, smoothing the connection surface between the super duplex stainless steel outboard tube 1 and the super duplex stainless steel cladding plate 3, reducing the seawater resistance of the protruding part of the super duplex stainless steel outboard tube 1. At the same time, the outer circle is welded to the hull plate 2 to protect the hull plate 2 from corrosion by acidic washing water.

[0041] It should be understood that numerous specific implementation decisions can be made during the development of any practical implementation, such as in any engineering or design project. Such development efforts may be complex and time-consuming, but for those skilled in the art who benefit from this disclosure, the development effort will be a routine work of design, manufacturing, and production without requiring much experimentation.

[0042] It should be noted that the above embodiments are only used to illustrate the technical solution of this utility model and are not intended to limit it. Although this utility model has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solution of this utility model without departing from the spirit and scope of the technical solution of this utility model, and all such modifications or substitutions should be covered within the scope of the claims of this utility model.

Claims

1. A corrosion protection device for the hull plate of an outboard pipe in a desulfurization system, comprising a hull plate (2), characterized in that: Also includes: Super duplex stainless steel outboard tube (1), which is inserted through and welded to the hull plate (2) for discharging desulfurization washing water; Super duplex stainless steel composite plate (3), the super duplex stainless steel composite plate (3) is a circular plate, which is sleeved on the outer periphery of the super duplex stainless steel overboard tube (1) and arranged coaxially. The inner ring edge of the super duplex stainless steel cladding plate (3) is welded to the outer wall of the super duplex stainless steel outer tube (1), and its outer ring edge is welded to the surface of the hull plate (2). Multiple plug welding holes are provided between the inner and outer ring edges of the super duplex stainless steel cladding plate (3). The hull plate (2) is fixed by plug welding through the plug welding holes. The welds between the super duplex stainless steel cladding plate (3), the hull plate (2), and the super duplex stainless steel outer tube (1) form a continuous sealing structure.

2. The anti-corrosion device for the outer pipe of the desulfurization system as described in claim 1, characterized in that: The material of the super duplex stainless steel composite plate (3) is any one of SS25073, SS22059 or SMO254.

3. The anti-corrosion device for the outer pipe of the desulfurization system as described in claim 1, characterized in that: The thickness of the super duplex stainless steel composite plate (3) is 3-5 mm.

4. The anti-corrosion device for the outer pipe of the desulfurization system as described in claim 1, characterized in that: The outer diameter of the super duplex stainless steel composite plate (3) is not less than 3 times the outer diameter of the super duplex stainless steel outer tube (1), and the inner diameter of the super duplex stainless steel composite plate (3) is equal to the outer diameter of the super duplex stainless steel outer tube (1) plus 20mm.

5. The anti-corrosion device for the outer pipe of the desulfurization system as described in claim 1, characterized in that: The plug welding holes are slotted holes (4) and are evenly arranged along the circumference of the super duplex stainless steel composite plate (3).

6. The anti-corrosion device for the outer pipe of the desulfurization system as described in claim 1, characterized in that: The super duplex stainless steel composite plate (3) is made of two semi-circular ring plates spliced ​​together.

7. The anti-corrosion device for the outer pipe of the desulfurization system as described in claim 1, characterized in that: A corrosion-resistant metal layer is overlaid at the connection between the super duplex stainless steel composite plate (3) and the hull plate (2) and the super duplex stainless steel outer tube (1).

8. The anti-corrosion device for the outer pipe of the desulfurization system as described in claim 1, characterized in that: The end of the super duplex stainless steel outboard tube (1) protrudes 14-20 mm beyond the outer surface of the hull plate (2). The super duplex stainless steel cladding plate (3) covers the protrusion and is welded to the protrusion to form a smooth flow guide surface.

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