Full Welded Ball Valves are widely used in gas process or transportation industry for conventional on-off, emergency shut off and quick opening and controlling the flow. Top flange is designed per ISO5211 for easy amount various type of actuator.
Design Std: API, BS, DIN, JIS, GB
Product Material: ASTM A105, F11, F22, LF1, 304, 316, 304L, 316L
Full welded ball valve infomation:
1. Blow-out proof stem
For the purpose of preventing the stem from flying off resulting in abnormal rising of the inner pressure of valve, shoulder is fixed at the lower part of the stem. In addition, in order to prevent leakage resulting from burnout of packing set of the stem in a fire, thrust bearing is set at the contact position of the shoulder at lower part of the stem and valve body. Thus an inverse seal seat is formed which will prevent leakage and avoid accident.
2. Anti-fire safe design
When the trunnion ball valve be used normally, its sealed by seat and ball surface, seat retainer sealed by O-ring and body, this is soft sealed and reliable sealing. When the seat and O-ring are burnt, the seat retainer and body will be sealed by expanded graphite. Thus act anti-fire safe purpose.
3. Anti-static device
In order to prevent friction among ball, stem and PTFE that generates static electricity which may light the combustibles and explosives that cause an accident, in this ball valve, static-conduction spring is set between the stem and the ball, the stem and the body. Thus static electricity is conducted to ground and system safety is secured.
4. Free leakage of body Sealed construction
The connective position of valve body and bonnet is double sealed by gasket and O-ring, on this base, such factors as fire, high temperature, shock and uneven opening or closing of the torque all can't induce external leakage.
5. Low torque in operation
The self-lubricated bearings are installed at the friction of stem, resulting in wear resistance, fiexibility of operation and low torque.
6. Double block & bleed(DBB valve)
When ball is full open or close position, the transmitter substance in center cavity of body can be released by drainage and emptying devices. In addition, the over loaded pressure in the center cavity of valve can be released to low pressure end by self relief seat.