How Much do You Know about Fully Welded Ball Valves?

Because the seat of the full welded ball valve is composed of a carbonized Teflon sealing ring and a disc spring, it has strong adaptability to changes in pressure and temperature, and will not produce any within the marked pressure and temperature range.

1. Product structure and features

City gas: gas output pipelines, main lines and supply lines of various branch lines, etc.

Centralized heating: output pipelines, main lines, branch lines of large heating equipment.

Heat exchanger: opening and closing of pipes and circuits.

Iron and steel plants: various fluid pipes, exhaust gas discharge pipes, gas and heat supply pipes, fuel supply pipes.

Various industrial equipment: various heat treatment pipelines, various industrial gas and thermal pipelines.

2. Characteristics:

The fully welded ball valve, there will be no external leakage and other phenomena.

The processing of the sphere is tracked by an advanced computer detector, so the processing accuracy of the sphere is high.

Because the valve body material is the same as the pipe material, there will be no uneven stress, nor deformation due to earthquakes and vehicles passing through the ground, and the pipe is resistant to aging.

The sealing ring body is made of 25% Carbon (carbon) RPTFE material to ensure no leakage (0%).

Directly-buried welded ball valves can be buried directly underground, without the need to build tall and large valve wells, only need to set up small shallow wells on the ground, which greatly saves construction costs and engineering time.

According to the construction and design requirements of the pipeline, the length of the valve body and the height of the valve stem can be adjusted.

The processing precision of the sphere is very precise, the operation is light, and there is no bad interference.

The use of advanced raw materials can guarantee the pressure above PN25.

Compared with products of the same specification in the same industry, the valve body is small and the appearance is beautiful.

In order to ensure the normal operation and use of the valve, the service life is more than 15 years.

3. Features

1. The valve body is made of a welded steel pipe.

2. The ball pad adopts reinforced polytetrafluoroethylene.

3. Valve stem adopts an explosion-proof design.

4. Temperature range: -60-200℃

5. Drive mode: manual or turbo transmission.

6. Testing standard: API 598

4. Installation

(1) Lifting.

The valve should be lifted in the correct way. In order to protect the valve stem, do not tie the lifting chain to the handwheel, gearbox or actuator. Do not remove the protective caps on both ends of the valve sleeve before welding.

(2) Welding.

Directly buried fully welded ball valves are connected to the main pipeline by welding. The quality of the welding seam must comply with the grade II film standard of "Panflex Melt Welding Welding Joint Radiography" (GB3323—2005). Usually, single welding cannot fully guarantee all the qualifications, so when ordering the valve, the manufacturer should be required to add 1.0m length at both ends of the valve Sleeve tube, once the weld is unqualified, there is still enough length to cut off and re-weld the unqualified weld. When the ball valve is welded to the pipeline, the valve should be in the 100% fully open position to prevent the ball valve from being damaged by splashing welding slag and to ensure the valve The internal seal temperature does not exceed 140 degrees Celsius, and appropriate cooling measures can be taken when necessary.

(3) Masonry of valve wells.

The direct-buried fully welded ball valve adopts a special structural design and is maintenance-free. Before the burial, the outer side of the valve is coated with a special anti-corrosion coating of Pu. At the same time, three injection pipes for the emergency grease injection of the valve seat and the stem, respectively. The cavity venting tube and valve stem are properly extended according to the depth of the ground so that the staff can complete various operations on the ground. After the direct burial is realized, a small valve hand well can be built. For conventional non-fully welded ball valves, they cannot be buried directly, and large valve wells need to be built. As a result, dangerous sealed spaces are formed, which is not conducive to safe operation. At the same time, the valve body itself and the bolt connection parts of the valve body and the pipeline will be corroded, which will affect the service life of the valve.

5. Daily operation and maintenance

In order to prolong the life of the valve, the valve should be operated and maintained according to the following procedures.

1 operation

The frequent operation of the valve can not only prevent impurities from accumulating on the surface of the valve seat or ball but also avoid excessive wear on the inlay of the valve seat.

(1) Opening and closing time requirements. Excessive valve switching will cause excessive valve twisting load. And the valve stem is damaged; the switch is too slow will cause the valve seat surface to be washed and worn by the medium for a long time. Therefore, the operating time should be kept within an appropriate range. According to experience, the lower limit of the valve's switching time (seconds) control range can be half of the nominal valve size (inch), and the upper limit can be estimated by 5 times of the nominal valve size (inch).

(2) When the valve is in operation, the valve ball should be fully open or fully closed, and should not be in the half-open or half-close position to avoid damage to the valve seat.

2 Routine maintenance

The valve seat cavity is the most contaminated area of the pipeline valve. In order to ensure the freedom of movement of the valve seat, it should be cleaned once a year, and the well should regularly check the tightness of the valve through the sewage nozzle. The valves of the auxiliary gas mainline are often seldom adjusted. At least once a year, they should be opened and closed and injected with a proper amount of grease to prevent the ball and valve seat from gluing and the sub-grinding between the valve ball and the valve seat.

Full Welded Ball Valve company good technical characteristics make the entire gas pipeline into one (all welded), enhance the overall stress resistance of pipelines (including valves), anti-geological disasters (such as geological collapse )Ability. Reduce the possibility of air leakage. The reliability of the valve is improved, the life is extended, and the installation and maintenance are also very convenient.