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What kind of working conditions need to select the stop valve

Time of issue:2021-07-14

(Summary description)Stop valve is one of the more widely used valves. The reason why it is widely popular is that in the process of opening and closing, the friction between the sealing surfaces is small, it is relatively durable, the opening height is not large, it is easy to manufacture, and it is convenient to maintain. It is not only suitable for medium and low pressure, but also suitable for high pressure. The closing principle of the stop valve is to make the sealing surface of the valve disc and the sealing surface of the valve seat close together by relying on the pressure of the valve rod to prevent the medium from flowing. It can be used to control the flow of air, water, steam, various corrosive media, mud, oil, liquid metal and radioactive media. Therefore, this type of shut-off valve is very suitable for cut-off or regulation and throttling. Because the opening or closing stroke of the valve stem is relatively short, and it has a very reliable cut-off function, and because the change of the valve seat opening is directly proportional to the stroke of the valve disc, it is very suitable for regulating the flow. The stem axis of the stop valve is perpendicular to the sealing surface of the valve seat. The relatively short opening or closing stroke of the valve stem and its reliable cut-off action make the valve very suitable for medium cut-off or adjustment and throttling. Once the valve disc of the stop valve is in the open state, the contact between the valve seat and the sealing surface of the valve disc will be no longer, and it has a very reliable cut-off action, so this kind of valve is very suitable for medium cutting or regulating and throttling. Once the stop valve is in the open state, there will be no contact between the valve seat and the sealing surface of the valve disc, so the mechanical wear of the sealing surface is small. Because most of the valve seats and the valve disc are easy to repair or replace, it is not necessary to remove the whole valve from the pipeline when the sealing elements are replaced, which is very suitable for the occasions where the valve and the pipeline are welded together. When the medium passes through this kind of valve, the flow direction changes, so the flow resistance of the stop valve is higher than that of other valves. The commonly used stop valves are as follows: 1. Angle stop valve; In the angle globe valve, the fluid only needs to change its direction once, so that the pressure drop through the valve is smaller than that of the conventional globe valve. 2. DC stop valve; In direct flow or Y-shaped stop valve, the flow channel of the valve body is inclined to the main flow channel, so the damage degree of the flow state is smaller than that of the conventional stop valve, so the pressure loss through the valve is correspondingly smaller. 3. Plunger type stop valve: this type of stop valve is a variant of conventional stop valve. In this valve, the disc and seat are usually designed based on the principle of plunger. The valve disc is polished into a plunger and connected with the valve stem. The sealing is realized by two elastic sealing rings on the plunger. The two elastic sealing rings are separated by a collar, and the sealing ring around the plunger is firmly pressed by the load exerted on the valve cover by the valve cover nut. The elastic sealing ring can be replaced and can be made of various materials. The valve is mainly used for "opening" or "closing", but it is equipped with special plunger or special ring, which can also be used to adjust the flow.

What kind of working conditions need to select the stop valve

(Summary description)Stop valve is one of the more widely used valves. The reason why it is widely popular is that in the process of opening and closing, the friction between the sealing surfaces is small, it is relatively durable, the opening height is not large, it is easy to manufacture, and it is convenient to maintain. It is not only suitable for medium and low pressure, but also suitable for high pressure. The closing principle of the stop valve is to make the sealing surface of the valve disc and the sealing surface of the valve seat close together by relying on the pressure of the valve rod to prevent the medium from flowing. It can be used to control the flow of air, water, steam, various corrosive media, mud, oil, liquid metal and radioactive media. Therefore, this type of shut-off valve is very suitable for cut-off or regulation and throttling. Because the opening or closing stroke of the valve stem is relatively short, and it has a very reliable cut-off function, and because the change of the valve seat opening is directly proportional to the stroke of the valve disc, it is very suitable for regulating the flow.
The stem axis of the stop valve is perpendicular to the sealing surface of the valve seat. The relatively short opening or closing stroke of the valve stem and its reliable cut-off action make the valve very suitable for medium cut-off or adjustment and throttling.
Once the valve disc of the stop valve is in the open state, the contact between the valve seat and the sealing surface of the valve disc will be no longer, and it has a very reliable cut-off action, so this kind of valve is very suitable for medium cutting or regulating and throttling.
Once the stop valve is in the open state, there will be no contact between the valve seat and the sealing surface of the valve disc, so the mechanical wear of the sealing surface is small. Because most of the valve seats and the valve disc are easy to repair or replace, it is not necessary to remove the whole valve from the pipeline when the sealing elements are replaced, which is very suitable for the occasions where the valve and the pipeline are welded together. When the medium passes through this kind of valve, the flow direction changes, so the flow resistance of the stop valve is higher than that of other valves.
The commonly used stop valves are as follows:
1. Angle stop valve; In the angle globe valve, the fluid only needs to change its direction once, so that the pressure drop through the valve is smaller than that of the conventional globe valve.
2. DC stop valve; In direct flow or Y-shaped stop valve, the flow channel of the valve body is inclined to the main flow channel, so the damage degree of the flow state is smaller than that of the conventional stop valve, so the pressure loss through the valve is correspondingly smaller.
3. Plunger type stop valve: this type of stop valve is a variant of conventional stop valve. In this valve, the disc and seat are usually designed based on the principle of plunger. The valve disc is polished into a plunger and connected with the valve stem. The sealing is realized by two elastic sealing rings on the plunger. The two elastic sealing rings are separated by a collar, and the sealing ring around the plunger is firmly pressed by the load exerted on the valve cover by the valve cover nut. The elastic sealing ring can be replaced and can be made of various materials. The valve is mainly used for "opening" or "closing", but it is equipped with special plunger or special ring, which can also be used to adjust the flow.

Categories:Industry news
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Time of issue:2021-07-14 14:19
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Stop valve is one of the more widely used valves. The reason why it is widely popular is that in the process of opening and closing, the friction between the sealing surfaces is small, it is relatively durable, the opening height is not large, it is easy to manufacture, and it is convenient to maintain. It is not only suitable for medium and low pressure, but also suitable for high pressure. The closing principle of the stop valve is to make the sealing surface of the valve disc and the sealing surface of the valve seat close together by relying on the pressure of the valve rod to prevent the medium from flowing. It can be used to control the flow of air, water, steam, various corrosive media, mud, oil, liquid metal and radioactive media. Therefore, this type of shut-off valve is very suitable for cut-off or regulation and throttling. Because the opening or closing stroke of the valve stem is relatively short, and it has a very reliable cut-off function, and because the change of the valve seat opening is directly proportional to the stroke of the valve disc, it is very suitable for regulating the flow.
The stem axis of the stop valve is perpendicular to the sealing surface of the valve seat. The relatively short opening or closing stroke of the valve stem and its reliable cut-off action make the valve very suitable for medium cut-off or adjustment and throttling.
Once the valve disc of the stop valve is in the open state, the contact between the valve seat and the sealing surface of the valve disc will be no longer, and it has a very reliable cut-off action, so this kind of valve is very suitable for medium cutting or regulating and throttling.
Once the stop valve is in the open state, there will be no contact between the valve seat and the sealing surface of the valve disc, so the mechanical wear of the sealing surface is small. Because most of the valve seats and the valve disc are easy to repair or replace, it is not necessary to remove the whole valve from the pipeline when the sealing elements are replaced, which is very suitable for the occasions where the valve and the pipeline are welded together. When the medium passes through this kind of valve, the flow direction changes, so the flow resistance of the stop valve is higher than that of other valves.
The commonly used stop valves are as follows:
1. Angle stop valve; In the angle globe valve, the fluid only needs to change its direction once, so that the pressure drop through the valve is smaller than that of the conventional globe valve.
2. DC stop valve; In direct flow or Y-shaped stop valve, the flow channel of the valve body is inclined to the main flow channel, so the damage degree of the flow state is smaller than that of the conventional stop valve, so the pressure loss through the valve is correspondingly smaller.
3. Plunger type stop valve: this type of stop valve is a variant of conventional stop valve. In this valve, the disc and seat are usually designed based on the principle of plunger. The valve disc is polished into a plunger and connected with the valve stem. The sealing is realized by two elastic sealing rings on the plunger. The two elastic sealing rings are separated by a collar, and the sealing ring around the plunger is firmly pressed by the load exerted on the valve cover by the valve cover nut. The elastic sealing ring can be replaced and can be made of various materials. The valve is mainly used for "opening" or "closing", but it is equipped with special plunger or special ring, which can also be used to adjust the flow.

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What kind of working conditions need to select the stop valve

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Stop valve is one of the more widely used valves. The reason why it is widely popular is that in the process of opening and closing, the friction between the sealing surfaces is small, it is relatively durable, the opening height is not large, it is easy to manufacture, and it is convenient to maintain. It is not only suitable for medium and low pressure, but also suitable for high pressure. The closing principle of the stop valve is to make the sealing surface of the valve disc and the sealing surface of the valve seat close together by relying on the pressure of the valve rod to prevent the medium from flowing. It can be used to control the flow of air, water, steam, various corrosive media, mud, oil, liquid metal and radioactive media. Therefore, this type of shut-off valve is very suitable for cut-off or regulation and throttling. Because the opening or closing stroke of the valve stem is relatively short, and it has a very reliable cut-off function, and because the change of the valve seat opening is directly proportional to the stroke of the valve disc, it is very suitable for regulating the flow. The stem axis of the stop valve is perpendicular to the sealing surface of the valve seat. The relatively short opening or closing stroke of the valve stem and its reliable cut-off action make the valve very suitable for medium cut-off or adjustment and throttling. Once the valve disc of the stop valve is in the open state, the contact between the valve seat and the sealing surface of the valve disc will be no longer, and it has a very reliable cut-off action, so this kind of valve is very suitable for medium cutting or regulating and throttling. Once the stop valve is in the open state, there will be no contact between the valve seat and the sealing surface of the valve disc, so the mechanical wear of the sealing surface is small. Because most of the valve seats and the valve disc are easy to repair or replace, it is not necessary to remove the whole valve from the pipeline when the sealing elements are replaced, which is very suitable for the occasions where the valve and the pipeline are welded together. When the medium passes through this kind of valve, the flow direction changes, so the flow resistance of the stop valve is higher than that of other valves. The commonly used stop valves are as follows: 1. Angle stop valve; In the angle globe valve, the fluid only needs to change its direction once, so that the pressure drop through the valve is smaller than that of the conventional globe valve. 2. DC stop valve; In direct flow or Y-shaped stop valve, the flow channel of the valve body is inclined to the main flow channel, so the damage degree of the flow state is smaller than that of the conventional stop valve, so the pressure loss through the valve is correspondingly smaller. 3. Plunger type stop valve: this type of stop valve is a variant of conventional stop valve. In this valve, the disc and seat are usually designed based on the principle of plunger. The valve disc is polished into a plunger and connected with the valve stem. The sealing is realized by two elastic sealing rings on the plunger. The two elastic sealing rings are separated by a collar, and the sealing ring around the plunger is firmly pressed by the load exerted on the valve cover by the valve cover nut. The elastic sealing ring can be replaced and can be made of various materials. The valve is mainly used for "opening" or "closing", but it is equipped with special plunger or special ring, which can also be used to adjust the flow.

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Failure analysis and treatment of bellows globe valve

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