The lift type flange check valve is a common type of valve used to prevent the backflow of media. It is connected by flanges and has excellent sealing performance and reliability. Here is a detailed introduction about it:

• Structural features: The valve disc moves up and down along the direction perpendicular to the axis of the valve body channel. The sealing pair is well-matched. The sealing surfaces of the valve disc and the valve seat are usually made by welding iron-based alloys or Samteley cobalt-based hard alloys. They are wear-resistant, heat-resistant, and corrosion-resistant. The valve body materials are diverse, and they can adapt to various pipe flange standards and sealing types.
• Working principle: When the medium flows in the forward direction, the pressure pushes the valve disc upward, causing it to move away from the valve seat and opening the passage; when the medium stops or flows backward, the valve disc, under the action of its own gravity and the pressure of the medium, descends to the sealing surface of the valve seat, achieving sealing and preventing the backward flow of the medium.
• Technical parameters: The nominal pressure is generally within the range of PN1.6MPa to 10.0MPa, the working temperature range is from -29℃ to 550℃, the nominal diameter is DN15 to DN1200mm, and the applicable media include water, oil products, steam, etc.
• Installation and Maintenance: During installation, it is essential to ensure that the medium flow direction is consistent with the arrow direction on the valve body. The valve is usually installed on a horizontal pipeline, but it can also be installed on a vertical pipeline as needed. During maintenance, the main task is to check if the sealing surfaces of the valve disc and valve seat are worn or corroded, and to promptly clean the impurities inside the valve body to ensure that the valve disc can move up and down flexibly.
• Application fields: Widely used in pipelines of industries such as petroleum, chemical engineering, power, and metallurgy. In these industries, it can effectively prevent the backflow of media and ensure the safe operation of equipment.