Floating Ball Valve
What's floating ball valve?
A Floating Ball Valve uses a rotating ball and a stem that provide on/off flow control.
The floating ball valve utilize natural line pressure to press and seal the ball against the downstream seat. The line pressure is exposed to a greater surface area - the entire upstream face of the ball, which is an area equal to the actual pipe size.
A floating ball valve is a valve with its ball floating (not fixed by a trunnion) inside the valve body, it drifts toward to the downstream side and tightly pushes against the seat under the medium pressure to ensure sealing reliability. The floating ball valve has simple structure, good sealing performance but the seat material is required to withstand the workload since the sealing pressure is bared by the seat ring. Due to unavailability of high performance seat material, floating ball valve is mainly used in middle or low pressure application.
When the valve is positioned where the bore is aligned in the same direction as the pipeline, it is in the open position, and fluid can pass downstream. NORTECH Floating ball valve is a new product manufactured by transformation the common valve and adoption of the up-to-date international standard.
Main features of NORTECH floating ball valve?
1. Special Seat Design
we adopts the design of flexible seal ring structure for the floating ball valve. When the medium pressure is low,the contact area of seal ring and ball is small. It will reduce friction and operating torque and ensure the tightness in the same time.When the medium pressure is increased,the contact area of seal ring and ball becomes bigger along with the elastic deformation of seal ring, so the seal ring can endure higher medium impact without being damaged.
floating seat under low pressure
floating seat under high pressure
2. Fireproof Structure Design
In case of fire during the use of valve, the seat ring made of PTFE Or other non-metal materials will be decomposed or damaged under high temperature and it will result in serious leakage of fluid,it's quite dangerous for the inflammable or explosive medium.The fireproof seal ring is set between ball and seat so that after the valve seat is burnt,the medium will push the ball rapidly towards the down stream metal seal ring to form the auxiliary metal to metal sealing structure which can effectively control valve leakage.In addition,the middle flange sealing gasket,which can ensure sealing even under high temperature .The fireproof structure design of floating ball valve conforms to requirements in APl607, APl6FA, BS 6755 and other standards.
Fireproof Structure Design of middle flange
Fireproof Structure Design of Stem(after burning)
Fireproof Structure Design of Seat
Fireproof Structure Design of Stem(normal use)
3. Anti-static Structure
The ball valve is designed with the anti- static structure and the static electricity discharge device to directly form a static channel between the ball and body through the stem so as to discharge the static electricity produced of friction of ball and seat,avoiding fire or explosion that may be caused by static sparkle and ensuring system safety.
Anti-Static structure design of ball valve with DN32 and above
Anti-Static structure design of ball valve smaller than DN32
4. Reliable Sealing of Valve Stem
The stem is designed with the shoulder at its bottom so that is will not be blown out by the medium even under the extreme condition such as abnormal pressure rise inside the valve cavity,failure of gland plate and etc.In addition,to avoid leakage after the stem packing is burnt in case of fire,the thrust bearing is set at the place where the stem shoulder and body contact to form a reverse sealing seat. The sealing force of the reverse seal will increase according to the increase of medium pressure,so as to ensure reliable stem sealing under various pressure,prevent leakage and avoid accident spreading.The V type packing sealing structure is designed for the stem,the V type packing can effectively change the pressing force and medium force of the gland into the sealing force of the stem. According to users' requirements, the disc spring loaded packing pressing mechanism can be adopted to make the sealing of stem packing more reliable.
bottom mounted stem will not blown out under medium pressure
top mounted stem may blow out under medium pressure
Before the packing is pressed
After the packing is pressed
the Spring loaded packing mechanism
5. Lock and Misoperation Prevention
The manual ball valve can be locked by a lock at the full Open or full close position. The 90° open and close positioning piece with lock hole is designed to avoid valve misoperation caused by non-authorised opreators, and it can also prevent valve opening or closing, or other accidents caused by pipeline vibration or unpredictable factors. It is very effective especially for inflammable and explosive oil,chemical and medical working pipelines or field tubing. The part on the head of the stem that is installed with the handle adopts flat design. Where the valve is opened, the handle is parallel to the pipeline, and closing indications of the valve are guaranteed to be correct.
Technical Specifications of floating ball valve?
| Nominal diameter |
1/2”-8”(DN15-DN200) |
| Connection Type |
Raised face flange |
| Design standard |
API 608 |
| Body material |
Stainless steel CF8/CF8M/CF3/CF3M |
| Ball material |
Stainless steel 304/316/304L/316L |
| Seat material |
PTFE/PPL/NYLON/PEEK |
| Working temperature |
Up to 120°C for PTFE |
|
|
Up to 250°C for PPL/PEEK |
|
|
Up to 80°C for NYLON |
| Flange end |
EN1092-1 PN10/16,ASME B16.5 Cl150 |
| Face to face |
ASME B 16.10 |
| ISO mounting pad |
ISO5211 |
| Inspection standard |
API598/EN12266/ISO5208 |
| Type of operation |
Handle lever/Manual gearbox/Pneumatic actuator/Electric actuator |
Product Show:
Application of floating ball valves
Our Floating Ball Valve can be widely utilized in petrochemical, chemical,steel,paper making, pharmaceutical and long-distance transport pipes.etc,nearly all the field.
