Ball valve in the maximum and minimum temperaturemaximum operating pressure is the number of spheres is open and close valve, also called the ball, the ball, the ball rotates around the body center line to achieve the opening, closing the valve action. It uses a plane tosection, section is round face.
Cross section of a sphere has the following properties:
The 1 section center line center and perpendicular to thecross section.
2 the center radius R radius R and the cross section ofthe distance between D and the ball is the following:r^2=R^2-d^2 spherical surface is through the center of thecircle is called the great circle cut plane, is not through the center of the circle is called round section. On the sphere, the shortest route between two points is thelength, after the great circle the points between the two aminor arc length, we put the arc length is called spherical distance two.
We know that the main characteristics of ball valve itself is compact, easy to operate and repair, suitable for water, solvents, acids, and natural gas general working media, but also applies to poor working conditions of media, such as oxygen, hydrogen peroxide, methane and ethylene. Ball valve body can be whole, it can be modular.
Nominal pressure rating ball valve (PN), can show thevalve the maximum working pressure in the normal temperature conditions. For example: PN4.0, shows thatits operating temperature at -290C to the maximum working pressure of 380C at 40 Bar (4.0MPa).
Ball valve plate showing the maximum operating pressureball valve which allows the maximum and minimum operating temperature. Ball valve high reliability is mainly because of what?
1), body and valve seat sealing will not happen toabrasion, sharp wear fault, not stuck at work (in the absence of lubricant), it can be reliably applied with the corrosive medium and low boiling point liquid;
2) built-in stem structure, eliminates the stem andpacking gland may fly out due to loose in a fluid under pressure accident;
3) uses ball valve and anti-static, refractory structure,suitable for conveying petroleum, natural gas, coal gaspipeline.
