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Electric ball valve-metal seated vs soft-seated type

What is the difference between an electric hard-sealed ball valve and an electric soft-sealed ball valve?
There are many types of ball valves, and the corresponding working conditions are different according to the structure, connection method and valve body material. However, in all types of ball valves, the sealing form is only divided into two categories: soft seal and hard seal. Since the sealing materials used are different, the performance characteristics of the products are different, so the applicable working conditions are naturally different.

electric ball valve

electric ball valve

1. From the price point of view, compared with the electric hard-sealed ball valve, the price of the electric soft-sealed ball valve will be cheaper and the cost will be lower!
2. In terms of material, electric hard-sealed ball valves use metal seats, mostly stainless steel + cemented carbide, with high machining accuracy and process technology requirements, and a wide range of applications. They can be used in normal temperature, low temperature, and high temperature and high pressure conditions. Electric soft-sealed ball valve, the valve seat is divided into fluoroplastics, rubber, resin and other types, mostly used in normal pressure and normal temperature, normal pressure and low temperature conditions.

3. From the structural mechanism
(1) The electric soft sealing ball valve is easy to achieve better sealing effect, and is resistant to corrosion, acid and alkali; the disadvantage is that it is not resistant to high temperatures, the sealing surface is easy to wear, and the mechanical properties are relatively poor. (Used for occasions with high sealing requirements, or corrosive media, and no particles at room temperature and pressure.)
(2) Electric hard-sealed ball valve is the opposite, which can withstand high temperature, abrasion resistance, and has good mechanical properties. The disadvantage is that the sealing performance of this type of seal is poor. (Generally, it is recommended to use hard-sealed ball valves for media that contain solid particles or wear and whose temperature is higher than 250 degrees.)
4. From the level of valve leakage, hard-sealed valves: Generally, they are Class V, and can reach Class VI as high as possible. Soft-seal valve: generally VI grade. The biggest problem with soft-seal valves is poor wear resistance. After using for a period of time, if there are solid impurities in the liquid medium, the valve seat may be worn, which will increase the leakage and decrease the sealing performance.

TH Valve is a professional manufacturer of butterfly valvegate valvecheck valveglobe valveknife gate valve, ball valve with API, JIS, DIN standard, used in Oil, Gas, Marine industry, Water supply and drainage, fire fighting, shipbuilding, water treatment and other systems, with Nominal Diameter of DN50 to DN1200, NBR/EPDM/VITON, Certificates & Approvals: DNV-GL, Lloyds, DNV, BV, API, ABS, CCS. Standards: EN 593, API609, API6D

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Fluorine-lined butterfly valve vs metal seated butterfly valve;
electric fluorine-lined butterfly valve vs electric metal seated butterfly valve;
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Schematic diagram of electric ball valve structure

The electric ball valve has a simple structure and is composed of a few parts. It has the advantages of small size, light weight, small installation size, small driving torque, easy operation and agility, and it can be quickly opened and closed only by rotating 90°. It has a good flow regulating effect and sealing characteristics; in the application range of large and medium caliber, medium and low pressure, the electric ball valve is one of the leading valves, and it is mainly used to cut off, distribute and change the flow direction of the medium in the pipeline. When the electric ball valve is fully opened, there is no resistance when the medium flows through the ball core port, so the pressure drop that occurs through the valve is very small, so it has better flow control characteristics.

O type ball valve O shaped ball core

O type ball valve O shaped ball core

Electric ball valve structure: There are many types of electric ball valves, which are generally divided into two categories according to different structural forms, namely O-shaped structure and V-shaped structure. The valve ball openings of the two are different, and the application is also different. O-type is generally suitable for shutting off. Use, occasionally adjust, but V-type is more suitable for adjustment (large adjustable ratio).

O-type ball valve structure:
The O-shaped ball valve is equipped with a ball with a middle through hole inside the valve body. A through hole with the same diameter as the pipe diameter is opened on the ball. When it is fully opened, it is a non-block valve with a large flow capacity and no directionality when fluid enters the valve. The sphere can rotate in the sealing seat, and there is a ring-shaped elastic body on both sides of the pipeline direction to achieve sealing. By rotating the ball 90°, the direction of the through hole can be changed, thereby realizing the opening and closing of the ball valve. ,

V-shaped ball valve structure:

V type ball valve, V-shaped ball core

V type ball valve, V-shaped ball core

The V-shaped ball valve core has a V-shaped structure. The valve core is a 1/4 spherical shell with a V-shaped gap. With the rotation of the ball, the opening area changes, but the shape of the opening surface is always triangular, and the flow characteristics are similar. Percentage, the adjustable ratio is large. It has the characteristics of large flow capacity, large adjustable range, shearing force, and tight closing. It is especially suitable for working conditions where fluid materials are fibrous. Generally, V-type ball valves are single-sealed ball valves. Not suitable for bidirectional use.
Related knowledge: The difference between O-shaped ball valve and V-shaped ball valve
Related products: Electric V-shaped ball valve Pneumatic O-shaped ball valve

TH Valve is a professional manufacturer of butterfly valvegate valvecheck valveglobe valveknife gate valve, ball valve with API, JIS, DIN standard, used in Oil, Gas, Marine industry, Water supply and drainage, fire fighting, shipbuilding, water treatment and other systems, with Nominal Diameter of DN50 to DN1200, NBR/EPDM/VITON, Certificates & Approvals: DNV-GL, Lloyds, DNV, BV, API, ABS, CCS. Standards: EN 593, API609, API6D

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O type |V type ball valve structure principle;
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Installation and maintenance of electric ball valve

Installation and maintenance of electric ball valve
Electric ball valve is a kind of valve used to control the pipeline medium and can realize remote control. It is an important equipment in the current industrial automation control system. Including pneumatic ball valves, and other valves cannot be used continuously. After storage or use for a certain period of time, if you want to continue to ensure its effective work and appropriately extend its service life, maintenance and maintenance must be done.
Electric ball valve installation and maintenance:

electric ball valve

electric ball valve

1. When the electric ball valve is closed, there is still pressurized fluid inside the valve body;
2. Before maintenance, release the pipeline pressure and keep the valve in the open position; disconnect the power or air source; separate the actuator from the bracket;
3. It is necessary to find out that the upstream and downstream pipelines of the electric ball valve have indeed been relieved of pressure before the disassembly and decomposition operations can be carried out;
4. Care must be taken to prevent damage to the sealing surface of parts, especially non-metal parts, when disassembling and reassembling. Special tools should be used when removing O-rings;
5. The bolts on the flange must be tightened symmetrically, gradually and evenly during assembly;
6. The cleaning agent should be compatible with the rubber parts, plastic parts, metal parts and working medium (such as gas) in the ball valve. When the working medium is gas, gasoline (GB484-89) can be used to clean the metal parts. Clean non-metal parts with pure water or alcohol;
7. The decomposed individual parts can be cleaned by dipping. Metal parts with undecomposed non-metal parts can be scrubbed with a clean, fine silk cloth impregnated with cleaning agent (to prevent fibers from falling off and adhering to the parts). When cleaning, remove all grease, dirt, glue, dust, etc. adhering to the wall;
8. After cleaning, the non-metal parts should be taken out of the cleaning agent immediately, and should not be soaked for a long time;
9. After cleaning, it needs to be assembled after the cleaning agent of the washed wall surface is volatilized (can be wiped with a silk cloth not soaked in cleaning agent), but it should not be left for a long time, otherwise it will rust and be contaminated by dust;
10. New parts also need to be cleaned before assembling;
11. Use grease to lubricate. Grease should be compatible with ball valve metal materials, rubber parts, plastic parts and working medium. When the working medium is gas, for example, special 221 grease can be used. Apply a thin layer of grease on the surface of the seal installation groove, apply a thin layer of grease on the rubber seal, and apply a thin layer of grease on the sealing surface and friction surface of the valve stem;
12. Metal chips, fibers, grease (except those specified for use), dust, other impurities, foreign objects, etc., should not be allowed to contaminate, adhere or stay on the surface of the parts or enter the cavity during assembly.

Related knowledge: Pneumatic ball valve installation instructions

TH Valve is a professional manufacturer of butterfly valvegate valvecheck valveglobe valveknife gate valve, ball valve with API, JIS, DIN standard, used in Oil, Gas, Marine industry, Water supply and drainage, fire fighting, shipbuilding, water treatment and other systems, with Nominal Diameter of DN50 to DN1200, NBR/EPDM/VITON, Certificates & Approvals: DNV-GL, Lloyds, DNV, BV, API, ABS, CCS. Standards: EN 593, API609, API6D

V-type regulating ball valve

Working principle of pneumatic V-type regulating ball valve
The ball core of the pneumatic V-shaped regulating ball valve is designed with a special V-shaped notch, which has a shearing effect on the valve seat. It is especially suitable for media containing fibers, small solid particles, slurry and other media. According to different structural methods, it can generally be divided into flange and Wafer type; Pneumatic V-type ball valve is a fixed ball valve and also a single-seat sealed ball valve. It has the best adjustment performance among ball valves and can achieve flow adjustment. At the same time, since the valve core and seat are rotated without gaps, they can be wiped by themselves. The fouling on the ball and valve seat keeps a good seal between the ball and the valve seat.

electric V type ball valve

electric V type ball valve

Working principle of pneumatic V-shaped regulating ball valve:
Pneumatic V-shaped regulating ball valve realizes different degrees of proportionality according to the V-shaped angle of the V-shaped sphere. It is generally used in conjunction with a valve positioner to achieve proportional adjustment. The V-shaped spool is most suitable for various adjustment occasions and has a large rated flow coefficient. ,, The pressure loss is small, the use flow capacity is large, and it has accurate shut-off characteristics and control functions. The flow characteristics are approximately equal percentages. The opening and closing parts adopt the V-shaped ball structure, which completely solves the problem of easy deposition of medium in the valve cavity.
Features of pneumatic V-shaped regulating ball valve:
1. Pneumatic V-shaped ball valve V-shaped gap and valve seat produce a strong shear force to cut off impurities such as fibers, and has a self-cleaning function to avoid valve jamming.
2. The pneumatic V-type regulating ball valve has an inherent flow characteristic of approximately equal percentage and an adjustable ratio of up to 300:1, so it can provide precise control in a wide range of changes.

Note: Because the pneumatic V-type regulating ball valve is generally a single-seat sealed ball valve, it is not suitable for two-way use. Due to its streamlined shape and full right-angle rotation control, the maximum volume is extremely high, the flow capacity is particularly large, and the flow resistance is small.

pneumatic V type ball valve

pneumatic V type ball valve

Pneumatic V-type regulating ball valve principle dynamic diagram
The valve core of the pneumatic V-shaped regulating ball valve is designed as a V-shaped gap with a special switch. The V-shaped gap and the valve seat generate a strong shear force, which can cut off high-viscosity media containing fibers or small solid particles, and has a self-cleaning function , To avoid the phenomenon of valve jamming. Pneumatic V-shaped ball valve is suitable for regulation and control, with high stability. Even in the case of small flow or high-viscosity medium, it can also ensure the accuracy of control within the entire range; while O-shaped ball valve is suitable for cutting off, relatively It is economical.
There is a V-shaped opening on the sphere of the pneumatic V-shaped regulating ball valve. As the ball rotates, the opening area changes, but the shape of the opening surface is always triangular. The flow characteristics are approximately equal percentages, the adjustable ratio is large, and the pressure loss is small. The flow capacity is large, and it has accurate interception characteristics and control functions. The opening and closing parts adopt a V-shaped spherical structure, which completely solves the problem of easy deposition of medium in the valve cavity. It is suitable for fibrous and slurry fluids!
The angle of the V-shaped port of the pneumatic V-shaped ball valve can be customized to meet more precise shut-off characteristics and control functions. Generally, more V-shaped valves are used in slurry media. They are similar to cam flex valves and are much better than O-shaped valves. V-shaped ball valves are used as regulating valves. For example, if the medium is not clean, the flow coefficient is low, and the leakage level is high, etc. occasion.

Working principle of electric V-type regulating ball valve

V type ball valve drawing

V type ball valve drawing

The electric V-shaped regulating ball valve has a special-shaped V-shaped incision. When the valve is closed, the V-shaped incision and the valve seat form a wedge shape, which has a shearing effect. The electric V-shaped ball valve is suitable for the control of fibrous slurry, sewage and viscous particle media. It can prevent the seizure of dirt between the ball and the valve seat. It has a self-cleaning function and is a wide-ranging regulating valve.
When the electric V-shaped ball valve rotates, the V-shaped blade of the ball is tangent to the valve seat, thereby cutting off the fiber and solid matter in the fluid. However, the general ball valve does not have this function, so it is easy to cause the fiber impurities to get stuck when closed. , Bring great inconvenience to repair and maintenance. The valve core of the electric V-shaped ball valve will not be jammed by the fiber, and the flow rate of the pipeline medium is adjusted and controlled according to the change of the opening area of ​​the V-shaped gap.
Note: Since the electric V-type regulating ball valve is generally a single-seat sealing ball valve, it is not suitable for two-way use. The integral valve body structure is adopted, and there is no potential for leakage.
Features of electric V-shaped ball valve:
1. It has the advantages of compact structure, small volume, vertical and horizontal installation, etc., adopts movable metal valve seat, self-compensation function, and has superior sealing performance and long service life.
2. The electric V-shaped ball valve adopts a double-bearing structure, which has high mechanical stability and low starting torque, which ensures that the valve has excellent sensitivity and induction speed.
3. Maximum reliability (safety): The valve body is a whole, sturdy and durable, operation is not affected by pipeline pressure, and leakage of the valve body can be avoided.
4. The V-shaped gap and valve seat of the electric V-shaped regulating ball valve produce a strong shearing force to cut off impurities such as fibers, and has a self-cleaning function to avoid valve jamming.
5. Maximum flow volume: Due to the streamlined shape of the electric V-shaped ball valve and the full right-angle rotation control, the maximum volume is particularly high, the flow capacity is particularly large, and the flow resistance is small.

TH Valve is a professional manufacturer of butterfly valvegate valvecheck valveglobe valveknife gate valve, ball valve with API, JIS, DIN standard, used in Oil, Gas, Marine industry, Water supply and drainage, fire fighting, shipbuilding, water treatment and other systems, with Nominal Diameter of DN50 to DN1200, NBR/EPDM/VITON, Certificates & Approvals: DNV-GL, Lloyds, DNV, BV, API, ABS, CCS. Standards: EN 593, API609, API6D

related news /knowledge:
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Three-way ball valve T type vs L type

The difference between pneumatic three-way ball valve T type and L type
Pneumatic three-way ball valve is a new type of valve that has been widely used in recent years. It is mainly used to cut off, distribute and change the flow direction of the medium in the pipeline. According to the different internal structure, it can be divided into L type and T type, but From the appearance, there is no difference between the two! So what is the difference between the principles and applicable working conditions of the T-type and L-type pneumatic three-way ball valves? How to choose?

pneumatic-electric-three way ball valve-flange-crew-T-L-type

pneumatic-electric-three way ball valve-flange-crew-T-L-type

Pneumatic flanged three-way ball valve Pneumatic internal threaded three-way ball valve The common connection method of pneumatic three-way ball valve is flange or internal thread. Choose according to the actual working conditions of the pipeline! Then in the process of use, you should choose different structural forms according to different working conditions. From the technological point of view, the T-type ball valve can replace the L-type ball valve. The working principle diagrams of the two are as follows:
The L-type pneumatic three-way ball valve is used to switch the flow direction of the medium, which can connect two perpendicular channels (such as the L-type flow diagram). The T-type pneumatic three-way ball valve can not only switch the flow direction of the medium, but also make the three channels communicate with each other. At the same time, it can also close any channel to connect the other two channels to flexibly control the merging or splitting of the media in the pipeline.

Flow diagram-three way ball valve-T-type-L-type

Flow diagram-three way ball valve-T-type-L-type

The difference between T-type electric three-way ball valve and L-type electric three-way ball valve
Electric three-way ball valve is a new type of three-way port switching ball valve, which can be used to control the direction, split or merge of the three pipeline media. According to the different ball core structure, it can be divided into T-type or L-type, T-type electric The difference between the three-way ball valve and the L-type electric three-way ball valve is mainly the difference in the internal structure, and there is no difference in appearance! The T-shaped ball valve can connect three orthogonal pipelines with each other and cut off the third channel to split and merge, while the L-shaped ball valve can only connect two orthogonal pipelines, and cannot maintain the third pipeline at the same time. Connectivity only plays a role of distribution.
As can be seen from the above figure, the T-type ball valve is mainly used for the diversion or mixing of media, and the L-type ball valve is mainly used for reversing! L-type three-way ball valve is used for distribution and switching that do not require 3-way, and the operation is more convenient. There are only two valve positions, and there are positioning, and it can be turned 90 degrees without error; T-type three-way ball valve has a wide range of channels to choose from , There are many valve positions, generally there is no positioning, if you replace the L-type, it should be turned 180 degrees.
Electric flanged three-way ball valve Electric internal threaded three-way ball valve From the technological point of view, the T-type electric three-way ball valve can replace the L-type electric three-way ball valve, but the L-type ball valve cannot replace the T-type ball valve! In the process of use, different structures should be selected according to different working conditions, and the T-type ball valve can flow through but the L-type ball valve cannot.

TH Valve is a professional manufacturer of butterfly valvegate valvecheck valveglobe valveknife gate valve, ball valve with API, JIS, DIN standard, used in Oil, Gas, Marine industry, Water supply and drainage, fire fighting, shipbuilding, water treatment and other systems, with Nominal Diameter of DN50 to DN1200, NBR/EPDM/VITON, Certificates & Approvals: DNV-GL, Lloyds, DNV, BV, API, ABS, CCS. Standards: EN 593, API609, API6D

related news /knowledge: Working principle diagram of three-way valve; What is a ball valve?; Electric ball valve principle | Electric ball valve working principle

Electric ball valve principle | Electric ball valve working principle

Electric ball valve principle | Electric ball valve working principle
The electric ball valve is mainly composed of an electric actuator and a ball valve. The cock body is a ball with a 90-degree rotation. Electric ball valve is not only a good product for throttling, blocking, cutting, on-off, and diversion, it is also the first choice in the flow control system. It has many characteristics such as pressure resistance,

electric ball valve

electric ball valve

temperature resistance, corrosion resistance, low flow resistance, long service life, and wide application range. To
The working principle of the electric ball valve: The electric ball valve mainly relies on the adjustment of the electric current in the electric actuator to operate the ball valve. The input and output signal of the electric actuator is 4-20mA and the standard signal of the 220VAC power supply. The motor group drives the gear and worm torque to control the opening and closing of the ball valve, to distribute and change the flow direction of the medium or to adjust the proportional degree of the spool rotation, namely The opening of the valve is proportional to the control fluid, or percentage.
Electric ball valve application:

electric V type ball valve

electric V type ball valve

The electric ball valve does not need to be operated manually, but is operated intelligently. In the production process, the environmental site determines all the factors. Electric ball valves used in high pressure, high temperature or low pressure and low temperature environments are different. The following points should be noted:
1. For low temperature and low pressure, the material does not need to be adjusted too much.
2. In the case of high pressure and high temperature, high temperature and high pressure resistant materials should be used as the electric ball valve material, such as stainless steel and alloy, which can withstand high pressure and high temperature.
3. The internal parts of the electric ball valve need to be replaced to reduce the damage to the valve core, and it is also conducive to the flow of the medium and avoid the coking and blockage of the electric ball valve.
4. When the electric ball valve is opened, some machinery to avoid vibration can be installed to prevent the internal structure of the electric ball valve spool from being damaged when it is opened.

TH Valve is a professional manufacturer of butterfly valvegate valvecheck valveglobe valveknife gate valve, ball valve with API, JIS, DIN standard, used in Oil, Gas, Marine industry, Water supply and drainage, fire fighting, shipbuilding, water treatment and other systems, with Nominal Diameter of DN50 to DN1200, NBR/EPDM/VITON, Certificates & Approvals: DNV-GL, Lloyds, DNV, BV, API, ABS, CCS. Standards: EN 593, API609, API6D

Product features and advantages of ball valve

Product features of ball valve:
1. The three-way ball valve adopts an integrated structure in structure, with a four-sided valve seat sealing type, fewer flange connections, high reliability, and a lightweight design.

ball valve (8)

ball valve (8)

2. The three-way ball core is divided into T type and L type, with long service life, large circulation capacity and low resistance.

3. The ball valve is divided into two types: single-acting and double-acting according to the action type. The single-acting type is characterized in that once the power source fails, the ball valve will be in the state required by the control system.

Advantages of ball valve:

1. The fluid resistance is small, and its resistance coefficient is equal to that of a pipe section of the same length.

2. Simple structure, small size and light weight.

3. It is tight and reliable, and the sealing surface material of the ball valve is widely used in plastics and has good sealing performance. It has also been widely used in vacuum systems.

4. It is easy to operate and open and close quickly. It only needs to rotate 90° from fully open to fully closed, which is convenient for remote control.

5. The maintenance is convenient, the structure of the ball valve is simple, the sealing ring is generally movable, and it is convenient to disassemble and replace.

6. It has a wide range of applications, with a diameter ranging from a few millimeters to a few meters, and can be applied in high vacuum or high pressure.

This type of valve is a high-pressure ball valve commonly used in existing mines. It bears high pressure and adopts a U-shaped card quick connection method. It can be quickly installed and disassembled in the daily production and use of the mine, and is convenient to use.

The ash unloading ball valve is mainly used to cut off, distribute and change the flow direction of the medium in the pipeline. The ash unloading ball valve can be divided into floating ball type, fixed ball type, and elastic ball type. The ash unloading ball valve is mainly used to cut off or connect the medium in the pipeline. It can also be used for fluid adjustment and control. The ash unloading ball valve Compared with other valve types, it has angular stroke output torque, opens quickly, is stable and reliable, and is widely applicable. The working principle of the ash unloading ball valve is to make the valve unblocked or blocked by rotating the valve.

Electric ball valve structure is composed of only a few parts, saving data; small size, light weight, small installation size, electric ball valve structure diagram, small driving torque, pressure regulating valve, easy and agile operation, only need to rotate 90° Fast opening and closing; and also has a good flow regulation effect and sealing characteristics at the same time, in the application of large and medium caliber, medium and low pressure, electric ball valve is the dominant valve form. When the electric ball valve is in the fully open position, the thickness of the butterfly plate is the resistance when the medium flows through the valve body, so the pressure drop that occurs through the valve is small, so it has better flow control characteristics. Electric ball valves have two sealing types: elastic seal and metal seal. Elastic sealing valve, the sealing ring can be embedded in the valve body or attached to the periphery of the butterfly plate. Valves with metal seals generally have a longer life than valves with elastic seals, but it is difficult to achieve a complete seal. Metal seals can adapt to higher operating temperatures, while elastic seals have the disadvantage of being limited by temperature. If the electric ball valve is requested to be used as a flow control, it is important to accurately select the size and type of the valve. The construction principle of the electric ball valve is particularly suitable for manufacturing large diameter valves. Electric ball valves are not only widely used in general industries such as petroleum, gas, chemical, and water disposal, but also used in cooling water systems of thermal power stations. Commonly used electric ball valves include wafer type electric ball valves and flange type electric ball valves. Wafer type electric ball valve uses double-head bolts to connect the valve between two pipe flanges. Flange type electric ball valve is equipped with flanges on the valve. The two flanges on the valve are connected to the pipe flanges with bolts. The strength performance of the valve refers to the ability of the valve to withstand medium pressure. The valve is a mechanical product that is subjected to internal pressure, so it must have sufficient strength and rigidity to ensure long-term use without cracking or deformation. Pneumatic ball valve is composed of ball valve and pneumatic actuator. Pneumatic actuator is divided into double-acting pneumatic actuator and single-acting pneumatic actuator. Through solenoid valve control, ball valve switching action is realized. The pneumatic ball valve can realize intelligent control, quickly open or close the pipeline, and can effectively control and manage the pipe network.

TH Valve is a professional manufacturer of butterfly valvegate valvecheck valveglobe valveknife gate valve, ball valve with API, JIS, DIN standard, used in Oil, Gas, Marine industry, Water supply and drainage, fire fighting, shipbuilding, water treatment and other systems, with Nominal Diameter of DN50 to DN1200, NBR/EPDM/VITON, Certificates & Approvals: DNV-GL, Lloyds, DNV, BV, API, ABS, CCS. Standards: EN 593, API609, API6D

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What is a ball valve?;
Electric ball valve principle | Electric ball valve working principle;
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