The obvious advantages of the stop valve are:

During the opening and closing process, the friction between the valve disc and the sealing surface of the valve body is smaller than that of the gate valve, so it is wear-resistant.

The opening height is generally only 1/4 of the diameter of the valve seat channel, so it is much smaller than the gate valve.

Usually there is only one sealing surface on the valve body and the valve disc, so the manufacturing process is relatively good and easy to repair.

The function of the stop valve is mainly to cut off the pipeline medium. Compared with the gate valve, it has better adjustment function, smaller opening height, shorter closing time, convenient manufacturing and repair, and the sealing surface is not easy to wear and scratch. The sealing function is better and the service life is long; the valve body structure design of the stop valve is relatively curved, so the flow resistance is large and the energy consumption is large; it is suitable for steam, oil and other media, but not suitable for media with high viscosity, particles, easy coking, and easy precipitation. Medium and high pressure stop valves, large diameter stop valves can choose balanced structure, the extended product of stop valve - throttle valve,

Control the pressure and flow of the medium by changing the flow channel section. Except for the streamline cone of the opening and closing parts, most of the others are the same as the stop valve.

When the stop valve is open, the flow rate has reached the maximum when the opening height of the valve disc is 25% to 30% of the nominal diameter, indicating that the valve has reached the full open position. Therefore, the full open position of the stop valve should be determined by the stroke of the valve disc.

Advantages of stop valve:

1. Simple structure, convenient manufacturing and maintenance.

2. Small working stroke, short opening and closing time.

3. Good sealing, small friction between sealing surfaces, and long service life.

Disadvantages of stop valve:

1. Large fluid resistance, large force required for opening and closing.

2. Not suitable for media with particles, high viscosity, and easy coking.

3. Poor conditioning function.

Scope of use:

It is suitable for use as a cut-off valve on pipelines of heat transfer oil, toxic, flammable, highly permeable, polluting, and radioactive fluid media. It can also be used for regulation. It is an excellent product for creating leak-free factories. All castings of this valve are precision cast.

The stop valve refers to a valve in which the closure (valve disc) moves along the center line of the valve seat. According to this movement of the valve disc, the change of the valve seat port is proportional to the valve disc stroke. Because the valve stem of this type of valve has a relatively short opening or closing stroke and has a very good cut-off

function, and because the change of the valve seat port is proportional to the valve disc stroke, it is very suitable for regulating the flow rate. Therefore, this type of valve is very suitable for use as a cut-off or regulation and throttling, and the same pneumatic ball valve is also applicable.

The selection principle of the stop valve under the influence of its effect is:

1. Stop valves should be used on pipelines or equipment with high-temperature and high-pressure media. Such as thermal power plants, nuclear power plants, and high-temperature and high-pressure pipelines of petrochemical systems.

2. Pipelines with loose requirements for flow resistance on the pipeline. That is, the place where pressure loss is not a big consideration.

3. Needle valves, instrument valves, sampling valves, pressure gauge valves, etc. can be selected for small valves.

4. There is flow regulation or pressure regulation, but the regulation accuracy is not high, and the pipeline diameter is relatively small, such as the pipeline with a nominal diameter of ≤50mm, it is suitable to use.

5. Small and large fertilizers in synthetic industrial production should use high-pressure angle stop valves or high-pressure angle throttle valves with a nominal pressure of PN160 and a nominal pressure of 16MPa or PN320 and a nominal pressure of 32MPa.

6. In the desiliconization workshop and pipelines prone to coking in the Bayer process of alumina production, it is advisable to use direct current stop valves or direct current throttle valves with separate valve bodies, removable valve seats, and carbide sealing pairs.

7. For water supply and heating projects in urban construction, stop valves, balancing valves or plunger valves can be used for pipelines with smaller nominal diameters, such as pipelines with nominal diameters less than 150mm.