How to Distinguish the Quality of Butt-Welding Titanium Flanges?

A gasket is placed between the sealing surfaces of two flanges. After the nuts are tightened, the specific pressure on the gasket surface reaches a certain value, causing deformation that fills the irregularities on the sealing surface, thereby ensuring a tight and leak-free connection. A flange connection is a detachable joint. Based on the components being connected, flanges can be categorized as vessel flanges and pipe flanges. According to structural types, they include integral flanges, loose flanges, and threaded flanges. Common integral flanges include slip-on flanges and butt-welding flanges. Slip-on flanges have relatively poor rigidity and are suitable for applications with pressure p ≤ 4 MPa.

Butt-welding flanges, also known as high-neck flanges, offer greater rigidity and are suitable for applications with higher pressure and temperature. There are three types of flange sealing surfaces: flat-face sealing surfaces, which are suitable for low-pressure and non-toxic media applications; male-female sealing surfaces, which are suitable for moderately high-pressure applications; and tongue-and-groove sealing surfaces, which are suitable for flammable, explosive, toxic media, and high-pressure applications.

A gasket is a ring made of material capable of plastic deformation and possessing a certain strength. Most gaskets are cut from non-metal plates or manufactured to specified dimensions by specialized factories. Materials include asbestos rubber sheets, asbestos sheets, polyethylene sheets, etc. There are also metal-clad gaskets made by wrapping thin metal sheets (galvanized iron, stainless steel) around non-metal materials like asbestos. Additionally, spiral-wound gaskets are made by coiling thin steel strips together with asbestos strips.

Standard rubber gaskets are suitable for temperatures below 120°C. Asbestos rubber gaskets are suitable for steam temperatures below 450°C, oil temperatures below 350°C, and pressures below 5 MPa. For generally corrosive media, acid-resistant asbestos sheets are most commonly used. In high-pressure equipment and pipelines, metal gaskets made of copper, aluminum, No. 10 steel, or stainless steel, in lens-shaped or other configurations, are used. The contact width between high-pressure gaskets and the sealing surface is very narrow (line contact), and the machining finish of both the sealing surface and the gasket is high.