Titanium flanges are parts made of colored metal titanium or titanium alloy used for connecting pipes and pipe ends. Titanium flanges have holes, and bolts tightly connect two flanges. Flanges are sealed with gaskets, etc. Flange fittings refer to fittings with flanges (flanges or adapters). They can be formed by screwing or welding. Flange connections consist of a pair of flanges, a gasket, and several bolts and nuts. The gasket is placed between the two flange seal surfaces. After tightening the nuts, the pressure ratio on the gasket surface reaches a certain value, causing deformation and filling the uneven parts on the sealing surface, making the connection tight. According to the structure, there are titanium lap joint flanges, titanium butt-weld flanges, titanium threaded flanges, and titanium blind flanges, etc.
Titanium is a new type of metal. Its properties are related to the content of impurities such as carbon, nitrogen, hydrogen, and oxygen.
Titanium flanges have high strength. The density of titanium alloy is about 4.51g/cm³, only 60% of steel. The density of pure titanium is close to ordinary steel. The strength of some high-strength titanium alloys exceeds that of many alloy structural steels. Therefore, the specific strength (strength/density) of titanium alloys is much higher than other metallic structural materials.
Titanium flanges have high thermal strength. Titanium alloys can maintain the required strength at medium temperatures and can work for a long time at 450 to 500℃.
Titanium flanges have good corrosion resistance. The corrosion resistance of titanium alloys is much better than that of stainless steel when working in wet atmospheres and seawater media; they have strong resistance to pitting, acid corrosion, and stress corrosion; they have excellent corrosion resistance to alkalis, chlorides, organic materials containing chlorine, nitric acid, sulfuric acid, etc.
Titanium flanges have good low-temperature performance. The mechanical properties of titanium alloys can be maintained at low and ultra-low temperatures. Titanium alloys with good low-temperature performance and extremely low interstitial elements, such as TA7, can maintain a certain plasticity at -253℃. Therefore, titanium alloys are also an important low-temperature structural material.
Titanium flanges have high chemical activity. Titanium has a high degree of chemical activity and undergoes strong chemical reactions with O, N, H, Co, CO2, water vapor, and ammonia in the atmosphere. When the carbon content is greater than 0.2%, a hard TiC will form in the titanium alloy; at high temperatures, a hard tin surface will form; when the temperature is above 600℃, titanium absorbs oxygen to form a high-hardness hardening layer; when the hydrogen content increases, a brittle layer will also form. The depth of the hard and brittle surface layer can reach 0.1-0.15mm, and the degree of hardening is 20%-30%. Titanium also has a high chemical affinity and is easy to adhere to the friction surface.
Titanium flanges have small thermal elasticity. The thermal conductivity of titanium is 15.24w/(mk), which is about 1/4 of nickel, 1/5 of iron, and 1/14 of aluminum. The elastic modulus of titanium alloy is about half of that of steel, so its rigidity is poor and it is easy to deform.