KR-20260063127-A - DOSING VALVE

Abstract

An invention relating to a dosing valve for a diesel engine of a ship is disclosed. The disclosed dosing valve for a diesel engine of a ship is characterized by comprising: a body forming an inlet opening to one side and an outlet opening to the other side, and forming an installation hole portion that is open to the outside while connecting the inlet and the outlet; a seat portion that is seated on a stepped portion formed at a set position of the installation hole portion and forms a through hole portion corresponding to the installation hole portion; a stem that is axially inserted into the installation hole portion and moves axially by an external force to control the flow of fluid from the inlet to the outlet by opening and closing the through hole portion; and a coupling portion that detachably connects the seat portion to the body.

Inventors

• 김재규
• 여종현
• 변선영

Assignees

• 엠티에이치콘트롤밸브(주)

Dates

Publication Date

20260507

Application Date

20241030

Claims (4)

1. A body forming an inlet opening to one side and an outlet opening to the other side, and forming an installation hole portion that is open to the outside while connecting the inlet and the outlet; A sheet portion that is seated on a stepped portion formed at a set position of the above-mentioned installation hole portion and forms a through hole portion corresponding to the above-mentioned installation hole portion; A stem that is axially inserted into the above-mentioned installation hole, moves in the axial direction by an external force, and controls the fluid flowing from the inlet to the outlet by opening and closing the above-mentioned through hole; and A dosing valve for a diesel engine of a ship, characterized by including a coupling portion that detachably connects the above-mentioned seat portion to the above-mentioned body.
2. In Article 1, A dosing valve for a ship's diesel engine, characterized by including an eccentricity prevention member provided on the inner side of the body, which prevents eccentricity of the central axis of the stem relative to the central axis of the installation hole portion due to the fluid flow pressure.
3. In claim 1, the above-mentioned coupling part is, An expanded space portion formed by expanding in the corresponding area of the installation hole portion of the body to mount the above-mentioned seat portion; and A dosing valve for a ship's diesel engine, characterized by including a plug that is fixedly installed in the expansion space while stacked on the seat portion, forms a communication hole portion that guides the axial insertion and axial movement of the stem, and forms a channel corresponding to the outlet to be connected to the communication hole portion.
4. In Paragraph 2, The above body forms openings on both sides that are aligned with the above installation hole, thereby detachably connecting a bonnet into which the above stem is inserted, and A dosing valve for a ship's diesel engine, characterized by including a guide sleeve provided on the inner side of the above-mentioned eccentricity prevention part and the above-mentioned opening hole part, which guides the stem to reciprocate in the axial direction while maintaining a central axis.

Description

Dosing valve for marine diesel engines The present invention relates to a dosing valve for a marine diesel engine, and more specifically, to a dosing valve for precise control injection of a reducing agent and urea in an SCR system for reducing NOx in a marine diesel engine. To achieve precise fine sealing, the seat portion is positioned correctly on the body and then firmly fixed to the body using a plug. The invention enhances maintainability of the seat portion and plug through a structure that allows the seat portion and plug to be separated from the body. Furthermore, by applying a guide sleeve to the bonnet coupled to the upper side of the body to guide the reciprocating axial movement of the stem, the invention aims to prevent eccentricity of the stem's center axis, which interferes with the transfer of urea solution, by positioning the guide sleeve on the upper side of the seat portion. Recently, international environmental pollution regulations have been significantly strengthened, and new conventions regulating the emission of air pollutants from ships are being enacted and adopted. At the 62nd Marine Environment Protection Committee (MEPC) in July 2011, the International Maritime Organization (IMO) amended Annex IV of the Convention on the Prevention of Marine Pollution (MARPOL IV) to introduce stringent Tier III regulations on nitrogen oxide (NOx) emissions, which entered into force on January 1, 2016. Consequently, newly constructed ships are now required to be equipped with flue gas denitrification systems in their engines to operate within Emission Control Areas (ECAs). Therefore, flue gas denitrification systems are becoming indispensable for ships. In particular, since diesel engines operate under very lean fuel conditions with a high air-to-fuel ratio, they emit very little gaseous hydrocarbons and carbon monoxide. On the other hand, diesel engines emit relatively large amounts of nitrogen oxides (NOx) and particulate matter. The emitted particulates are multiphase substances consisting of solid insoluble carbon soot particles, liquid hydrocarbons in the form of lubricating oil and non-combustion fuel, soluble organic fractions (SOF), or so-called "sulfates" in the form of SO₃ + H₂O = H₂SO₄ . Both NOx and particulate matter are difficult-to-reduce diesel exhaust components, and recently, emission standards in the United States and Europe (EURO V regulations) have been set requiring a reduction of at least 50%, preferably 70-90%. Currently, many technologies such as DPF, SCR, LNT, and LNC are being developed to purify exhaust gases harmful to the human body. Among these, SCR (Selective Catalytic Reduction) technology has proven to be highly successful in reducing NOx under lean exhaust conditions. A conventional reducing agent dosing system comprises a reducing agent tank module filled with a reducing agent, a dosing valve that guides the precise control injection of urea solution, a dosing unit that mixes the reducing agent and air supplied through the tank module and the dosing valve, a nozzle that injects the reducing agent and air mixed through the dosing unit into a catalytic converter, and a controller that controls the ratio and injection amount of the reducing agent and air mixed through the dosing unit. Related technologies include Korean registered patent No. 10-1195148 (Title of invention: System for reducing harmful substances in exhaust gas and a ship including the same, Registration date: 2012.10.29.) and Korean registered patent No. 10-1345118 (Title of invention: Method for manufacturing titanium oxide nanotubes by anodic oxidation in an aqueous electrolyte, Registration date: 2013.12.26.). The technical configuration described above is provided as background technology to aid in understanding the present invention and does not constitute prior art widely known in the technical field to which the present invention belongs. FIG. 1 is a cross-sectional view showing the closed state of a dosing valve for a diesel engine of a ship according to one embodiment of the present invention. FIG. 2 is a cross-sectional view showing the open state of a dosing valve for a diesel engine of a ship according to one embodiment of the present invention. FIG. 3 is an exploded view of a key part of a dosing valve for a diesel engine of a ship according to one embodiment of the present invention. FIG. 4 is an enlarged view of a key part showing the closing operation of a dosing valve for a diesel engine of a ship according to one embodiment of the present invention. FIG. 5 is an enlarged view of a key part showing the opening operation of a dosing valve for a diesel engine of a ship according to one embodiment of the present invention. Hereinafter, an embodiment of a dosing valve for a ship's diesel engine according to the present invention will be described with reference to the attached drawings. In this process, the thickness of lines or the size of components shown in the drawings may be exag