Alloy blind plate is a special pipe fitting used to seal the ends of pipelines or equipment openings. It is made of alloy material and widely used in the industrial field.

1. Material characteristics
The alloy composition is diverse: common alloy elements include chromium (Cr), nickel (Ni), molybdenum (Mo), titanium (Ti), etc. Chromium can improve corrosion resistance and oxidation resistance, nickel enhances toughness and high-temperature performance, molybdenum can strengthen resistance to pitting and crevice corrosion, and titanium stabilizes carbon elements to prevent intergranular corrosion. For example, in nickel chromium alloy blind plates containing molybdenum, the molybdenum element significantly enhances the corrosion resistance of the blind plates in chloride ion environments.
Significant performance advantages: Compared to ordinary carbon steel blind plates, alloy blind plates have higher strength, stronger corrosion resistance, and superior high temperature resistance. Alloy blind plates can work stably for a long time in high-temperature, high-pressure, and highly corrosive environments such as chemical and petroleum industries, ensuring the safety of pipeline systems. In the catalytic cracking unit of a refinery, where there is high temperature, high pressure, and sulfide corrosion, alloy blind plates can effectively resist erosion and maintain the normal operation of the unit.

2. Structure and type
Overall structure: usually in the shape of a circular plate, the size matches the opening of the sealed pipeline or equipment, and the thickness is determined based on the usage pressure, temperature, and medium characteristics. Its sealing surface has various forms, commonly including flat, protruding, concave convex, mortise and tenon surfaces, etc., to meet different sealing needs.
Rich types:
Welding blind plate: connected to the pipeline by welding, with good sealing performance, suitable for high-pressure, toxic, flammable, and explosive medium pipelines. Welding alloy blind plates are often used at the cut-off of natural gas transmission pipelines to ensure sealing safety.
Flange blind plate: used in conjunction with flanges, connected by bolts for easy disassembly, and used for pipeline systems that require regular maintenance or repair. In some connection parts of chemical plants, flange alloy blind plates are used to facilitate the isolation of equipment and pipelines during maintenance.

3. Manufacturing process
Forging process: High quality alloy billets are used, and pressure is applied through forging equipment to produce plastic deformation and obtain the desired shape and size. Forged blind plates have dense structure and good mechanical properties, suitable for high pressure and critical parts. For special pipeline sealing in the aerospace field, forged alloy blind plates are often used.
Casting process: After heating and melting the alloy material, it is poured into a specific mold and cooled to form. This process is suitable for manufacturing blind plates with complex shapes, but the internal structure is relatively loose and requires subsequent processing. Some large and complex shaped alloy blind plates, such as blind plates for sealing inspection ports in large chemical equipment, can be cast using casting technology.
Processing technology: Mechanical processing of forged or cast blind plate blanks, including turning, drilling, milling, etc., to ensure dimensional accuracy and sealing surface quality.

4. Application Fields
Petrochemical industry: used for isolation, maintenance, pressure testing and other aspects of pipeline systems in refining and chemical production facilities. For example, in the process of petroleum refining, alloy blind plates are used to isolate different areas of the pipeline of the reforming unit during maintenance to prevent material leakage.
Power industry: used in power facilities such as thermal power generation and nuclear power plants for systems such as steam pipelines and circulating water pipelines. Alloy blind plates can ensure the sealing and isolation of coolant piping systems in nuclear power plants under specific operating conditions.
In the field of ocean engineering: In offshore drilling platforms, subsea pipelines and other facilities, due to the strong corrosiveness of the marine environment, alloy blind plates are used for pipeline connection and sealing to ensure system sealing and corrosion resistance. At the connection nodes of submarine oil pipelines, alloy blind plates are used to prevent seawater erosion and oil and gas leakage.