Tag Archive for: shut-off valve

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Principle of Globe Valve (Figure)

Globe Valve is also called stop valve, shut-off valve. The opening and closing part of the globe valve is a plug-shaped valve disc, the sealing surface is flat or cone, and the valve disc moves linearly along the centerline of the fluid. The movement form of the valve stem includes a lifting rod type (the valve stem is raised and lowered, the hand wheel does not lift), and there is a lifting rotating rod type (the hand wheel and the valve stem rotate and lift together, and the nut is set on the valve body). The stop valve is only suitable for fully open and fully closed, adjustment and throttling are not allowed.
Brief introduction to the principle of the globe valve:

globe cut-off valve working diagram-3D GIF animated presentation

globe cut-off valve working diagram-3D GIF animated presentation

To put it simply, the principle of the globe valve is to use the torsion of the valve stem to give a downward pressure on the sealing surface, and rely on the pressure of the valve stem to make the disc sealing surface and the valve seat sealing surface closely fit to prevent the inflow of the medium or adjust the flow rate of the medium. . The opening and closing part of the stop valve is a cylindrical valve disc, the sealing surface is flat or conical, and the valve disc moves linearly along the center line of the fluid. The movement mode of the valve stem includes a lifting rod type (the valve stem is raised and lowered, and the hand wheel does not lift), and there is also a lifting rotating rod type

Schematic diagram of shut-off valve (closed state)

Schematic diagram of shut-off valve (closed state)

(the hand wheel and the valve stem rotate and lift together, and the nut is set on the valve body). The globe valve is a forced sealing valve, so when the valve is closed, pressure must be applied to the disc to force the sealing surface to not leak.

The working principle of the stop valve:
We assume that there is a pipe with a lid. Water flows in from the bottom of the pipe and flows out toward the nozzle. The lid of the outlet pipe is equivalent to the closing part of the shut-off valve. If the pipe lid is lifted up by hand, the water will flow out. When the cap is closed, the water stops flowing, which is equivalent to the working principle of a shut-off valve.

The shut-off valve relies on rotating the hand wheel to make the valve stem rise and fall, and drive the valve disc to make a linear displacement parallel to the flow direction of the medium to achieve the purpose of opening and closing. The handwheel rotates in a clockwise direction, and the working medium enters from the channel under the valve disc. At this time, the applied sealing force must be equal to or greater than the sum of the required specific pressure generated on the sealing surface and the upward force of the medium.

Schematic diagram of shut-off valve (open state)

Schematic diagram of shut-off valve (open state)

Schematic diagram of shut-off valve (open state)

When the shut-off valve is opened, when the opening height of the disc is 25% to 30% of the nominal diameter, the flow has reached the maximum, indicating that the valve has reached the fully open position. Therefore, the fully open position of the shut-off valve should be determined by the stroke of the valve disc.
Note:
1. The shut-off valve only allows the medium to flow in one direction, and has directionality when installed. ,
2. The function of the shut-off valve is either 0 or 1, either through or not through. In other words, the shut-off valve is only suitable for fully open and fully closed, and adjustment and throttling are not recommended.

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 knowledge:
The working principle and characteristics of the globe valve;
Electric globe valve selection and application;
The working principle of butterfly valve (picture);

Electric globe valve selection and application

Electric shut-off valve selection, Electric shut-off valve application, globe valve also named shut off valve or cut off valve.
Advantages of electric shut-off valve:
Once the electric shut-off valve is in the open state, there is no contact between its valve seat and the sealing surface of the disc, so its sealing surface is less mechanically worn, because most of the electric shut-off valves have relatively easy repairs. Or there is no need to remove the entire valve from the pipeline when replacing the sealing

electric globe valve

electric globe valve

element,which is very suitable for the occasion where the valve and the pipeline are welded together. The most obvious advantage is that during the opening and closing process, the friction between the 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 passage, so it is much smaller than the gate valve. Usually there is only one sealing surface on the valve body and the valve flap, so the manufacturing process is better and it is easy to maintain. The flow direction of the medium through this type of valve has changed, so the flow resistance of the electric shut-off valve is higher than that of other valves.

Selection of electric shut-off valve:
Commonly used electric globe valves are electric straight-through globe valves, electric throttle valves, electric angle globe valves, electric DC globe valves, electric plunger globe valves, etc. In addition to electric throttle valves, other electric globe valves generally do not Make high-pressure choices.
1. Angle type electric shut-off valve; in the angle type electric shut-off valve, the fluid only needs to change its direction once, so that the pressure drop through this valve is smaller than that of the conventional structure of the electric shut-off valve.
2. DC type electric shut-off valve; electric shut-off valve in the DC type or Y-shaped electric shut-off valve, the flow passage of the valve body is in a diagonal line with the main flow path, so that the degree of damage to the flow state is smaller than that of the conventional electric shut-off valve, so it passes The pressure loss of the valve is correspondingly small.
3. Plunger type electric shut-off valve: This type of electric shut-off valve is a modification of the conventional electric shut-off valve. In this valve, the disc and valve seat are usually designed based on the plunger principle. The valve clack is polished so that the plunger and the valve stem are connected, and the sealing is achieved by two elastic sealing rings sleeved on the plunger. The two elastic sealing rings are separated by a sleeve ring, and the sealing ring around the plunger is pressed firmly by the load exerted on the bonnet by the bonnet nut.
Electric shut-off valve application:
If the electric shut-off valve is used in high-pressure occasions, it is generally connected by butt welding, or electric angle type shut-off valve is used. According to the material, you can choose carbon steel or 304 stainless steel. If the temperature is relatively high, you need to choose chromium-molybdenum steel or chromium-molybdenum-vanadium steel. The typical J941Y-170V electric high temperature and high pressure stop valve used in power plants.

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:
Classification of the globe valves-(1);
The working principle and characteristics of the globe valve;
Electric globe valve model coding method.
working principle of electric globe valve

Types and classifications of globe valve

Type of globe valve / Classification of globe valve
The globe valve, also called the shut off valve or cut-off valve, is the most widely used valve, which is mainly composed of a valve body, a valve clack, a valve cover, and a valve stem. The valve body and valve cover are pressure-bearing parts, and the valve clack and valve stem are internal parts. The shut-off valve is a valve in which the closing part (disc) moves along the center line of the valve seat. According to this movement form of the valve disc, the change of the valve seat port is proportional to the valve disc stroke.

Classification of stop valves:
According to the structure of the valve body, the globe valve is divided into right-angle type, straight-through type and direct-flow type.
1. The right-angle fluid only needs to change its direction once, so that the pressure drop through this valve is smaller

than that of a conventional shut-off valve. The valve body is mostly forged, which is suitable for shut-off valves with smaller passages and higher pressures.

Globe valve (2)

right-angle Globe valve (2)

2. The straight-through type is the most common structure. The medium inlet and outlet channels are 180° in the same direction, but the fluid resistance is the largest.

Globe valve (9)

straight-through Globe valve (9)

3. In the direct-flow or Y-shaped stop valve, the flow channel of the valve body is in an oblique line with the main flow channel, and the fluid resistance is small. It is mostly used for fluids containing solid particles or high viscosity.

Globe valve (1)

Y-shaped Globe valve (1)

Type of stop valve:
According to nominal pressure: vacuum, low pressure, medium pressure, high pressure, ultra high pressure valve, etc.;
According to working temperature: high temperature, medium temperature, normal temperature, low temperature, ultra-low temperature valve, etc.;

According to the driving mode: manual valve, power driven valve (electromagnetic, pneumatic, hydraulic, electric and various linkage valves), automatic valve, etc.;
According to the valve body material: cast iron, cast copper, cast steel, carbon steel, titanium, stainless steel valves, etc.;
By application sector: general purpose valves, power station valves, marine valves, metallurgical valves, pipeline valves, plumbing valves, etc.;
According to the structure: straight-through type, angle type, direct current type, etc.;
According to the connection form: internal thread, external thread, flange, welding,

clamp, clamp, ferrule, etc.;

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:
Pneumatic globe valve model preparation method;
Characteristics and working principle of electric globe valve;
The working principle and characteristics of the globe valve;
The difference between globe valve and check valve

Globe valve structures and design standard

Globe valve structure, Globe valve design standard
The shut-off valve is a particularly common shut-off valve, which is mainly used to connect or cut off the medium in the pipeline, and is generally not used to adjust the flow. The globe valve is suitable for a wide range of pressure and temperature, but it is generally used for medium and small diameter pipelines.

Globe valve (2)

Globe valve (2)

Globe valve (1)

Globe valve (1)

Globe valve (9)

Globe valve (9)

Structural principle of globe valve:
1. The center of the inlet and outlet of the shut-off valve are on the same straight line, and the fluid flows like an S-shaped sphere, so it is also called a spherical shut-off valve.
2. When the valve seat of the valve stem descends toward the bottom sealing surface and is pressed down, the medium stops flowing; when the valve stem rises, the medium passes through the flow path from below to above.
Globe valves generally have direction requirements during installation. The flow direction of the medium in the pipeline generally flows from bottom to top through the valve seat port, which is what we often call the so-called “low inlet and high outlet”. The purpose of this is to reduce fluid resistance and save effort in opening. In the closed state, the valve stem and the packing culvert are not in contact with the medium to ensure that the valve stem and the packing culvert are not damaged or leaked.

Globe valve structure diagram Globe valve structure and design standards:

name Globe valve structure Globe valve design standard
Typical Forged Steel Globe Valve 1. Flow channel JB/T 7746-1995: Shrinkage hole BS5352-1999: Through hole or shrinkage hole (CL150~800); Through hole (Cl1500) JPI-7S-36-1999: Through hole
2. Valve body and bonnet Connection: flange, thread or welding
3. Connection end JB/T 7746-1995: internal thread, socket welding or flange BS5362-1999: internal thread, socket, flange and butt welding JPI-7S-36- 1999: Internal thread, socket
JB/T 7746-1995
BS 5352-1999
JPI-7S-36-1999
Internal pressure self-sealing forged steel globe valve 1. Flow path: shrinkage hole
2. Connection between valve body and bonnet: internal pressure self-sealing
3. Connection end: butt welding, flange or socket
ASME B16.34-1996
Cast steel globe valve 1. Flow path: angle type, straight-through, direct current (Y type)
2. Connection between valve body and bonnet: flange
3. Connection end: flange or butt welding
4. Various types of discs can be used, Usually exposed rod, there are also a few smaller diameter valves with dark rod
JPI-7S-46-1999
JIS B2071-1999
JIS B2072-1999
JIS B2081-1999
JIS B2082-1999
BS 1873-1999
MSS-SP-42-1999
GB/T 12235-1989
BS 5160-1989
Bellows Sealed Globe Valve 1. Flow path: angle type, straight-through, direct current (Y type)
2. Connection between valve body and bonnet: flange
3. Connection end: flange or butt welding
4. Various types of discs can be used, It is usually an exposed stem, but there are also a few valves with smaller diameters that use double stem seals with concealed stem 5, bellows and packing
ASME B16.34-1996
Angle type high pressure globe valve 1. Flow path: angle type
2. Connection between valve body and bonnet: thread, clamp or welding
3. Various types of discs can be used. For ultra-high pressure valves, internal pressure self-balancing discs are usually used
4. The valve body can adopt integral type, two-piece type
5. Connection end: flange or butt welding
ASME B16.34-1996
GB/T 12235-1989
Lining stop valve 1. Flow channel: angle type, straight-through, direct current (Y type)
2. Connection between valve body and bonnet: flange
3. Connection end: flange or butt welding
4. Lining material is rubber, plastic, etc.
ASME B16.34-1996
Two-way three-way globe valve 1. Flow path: two-way three-way flow path
2. Connection between valve body and bonnet: flange
3. Connection end: flange or butt welding
ASME B16.34-1996
Cast steel discharge stop valve 1. Flow path: straight-through
2. Connecting end: flange
3. Disc: upward or downward expansion
4. Connection between valve body and bonnet: flange
ASME B16.34-1996
Three-way globe valve 1. Flow path: Tee
2. Connecting end: Flange
3. Disc: Plane seal
ASME B16.34-1996
Pressure gauge shut-off valve 1. Flow path: DC, right angle, three-way
2. Connection between valve body and bonnet: integral forging or thread
3. Connection end: external thread, clamp
4. Disc: Cone and flat
ASME B16.34-1996
Water seal stop valve 1. Flow path: DC
2. Connection end: socket welding, butt welding
3. Valve body and bonnet: both forged, with a chromium nickel steel or carbon steel
4. Disc: Cone seal (DN10~25mm) , Plane seal (DN32~200mm)
E101-1999
GB/T 12235-1999
ASME B16.34-1996
Slurry shut-off valve 1. Flow path: DC
2. Connection end: Flange
3. Valve body structure: The valve seat is clamped between the left and right valve bodies, and the left and right valve bodies are connected by bolts.
4. The valve body and the bracket are connected by bolts.
5. The valve cover: CL150 is forged as a whole, CL300 and CL400 are split type, using strut connection.
6. Disc: Cone surface is sealed into plane seal, or throttle type sealing surface is overlaid with hard alloy
GB/T 12235-1989
ASME B16.34-1996
Angle globe valve 1. Flow path: right angle
2. Connection end: flange
3. Valve body and bonnet: forged throttling type. The sleeve is drilled and the piston moves up and down in the sleeve to adjust the flow.
4. Valve body, valve Cover connection: bolt connection
API 6A-2002
Titanium Globe Valve 1. Flow path: straight-through
2. Valve body, bonnet, stuffing box, valve clack, valve stem are made of titanium
3. Valve body and bonnet connection: bolt connection
4. Valve clack is flat seal
GB/T 12235-1989

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:
The structure and connection of the American standard valve;
Classification of the globe valves-(2);
The working principle and characteristics of the globe valve;
Pneumatic globe valve model preparation method

Globe valve Model Compilation Instructions and Representation Method

Model Compilation Instructions for Globe Valves | Representation Method
Compilation instructions for cut-off valve model Description method of cut-off valve model Compilation instructions for cut-off valve model: Cut-off valve, also known as cut-off valve, is a forced-sealing valve. According to the domestic valve model standard, the model of the globe valve is represented by the valve type, drive mode, connection mode,

Globe valve (9)

Globe valve (9)

structure form, sealing material, nominal pressure, and valve body material code. The model of the globe valve is related to the correct understanding of the globe valve product, the importance of the type selection, and the guarantee of the safety of the working conditions. Some of the codes in the following globe valve model compilation are omitted, mainly for the model description of the existing globe valve products. If the material and structure of the customized cut-off valve product changes, please select according to the valve programming method, or call for details.
Representation method of globe valve model:
Additional code for stop valve: W means bellows, D means low temperature, B means heat preservation;
1) Type code of globe valve: J means globe valve;
2) Stop valve transmission mode: manual without code, 5 bevel gear, 6 pneumatic, 9 electric;
3) Connection mode of stop valve: 4 flange connection, 6 welding;
4) The structure of the globe valve: 1 straight-through type, 2 Z-type straight-through, 3 three-way, 4-angle type, 5 Y-type DC type, 6 balanced straight-through type, 7 balanced angle type, 8-pin type;
5) Seal material of globe valve: F fluorine rubber, H stainless steel, N nylon plastic, Y cemented carbide, M Monel alloy, W valve body directly processed;
6) The nominal pressure of the shut-off valve: 16 means that the pressure of 1.6mpa is 16 kilograms, PN1.6-32mpa, IN150LB-1500LB, 5-63K;
7) Globe valve body material: A titanium alloy, C carbon steel, I chromium molybdenum steel, P stainless steel 304,

electric globe valve

electric globe valve

R stainless steel 316;
Example of model compilation of globe valve:
J941H-16C Electric Flange Globe Valve
1. J: indicates the stop valve;
2. 9: indicates that the transmission mode is electric;
3. 4: The connection method is flange connection;
4. 1: The structure is a straight flow channel;
5. H: The sealing material is stainless steel;
6. 16: Indicates that the nominal pressure is 1.6MPa;
7. C: Indicates that the valve body material is carbon steel.

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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The working principle and characteristics of the globe valve;
Representation method of electric gate valve model;
Gate valve model meaning and representation method

working principle of electric globe valve

The principle of electric globe valve; The working principle of electric globe valve
Overview of electric shut-off valve:
The electric shut-off valve is equipped with an electric actuator on the basis of the shut-off valve, and the opening

electric globe valve

electric globe valve

and closing of the valve is controlled by an electric device. The connection between the valve and the actuator adopts a direct connection method. The electric actuator has a built-in servo system, no need to be equipped with a servo amplifier, input 4-20mA signal and 220VAC power supply to control the operation. It has the advantages of simple connection, compact structure, small size, light weight, low resistance, stable and reliable action, etc. It can also be operated manually on site according to requirements, with the actuator with hands and electric switching mechanism. In addition to local operations, remote operations can also be performed.
Working principle of electric shut-off valve:
The closing principle of the electric shut-off valve is to rely on the electric thrust to rotate the valve stem, so that the sealing surface of the disc and the sealing surface of the valve seat are closely attached to prevent the medium from flowing. The electric shut-off valve only allows the medium to flow in one direction and is directional when installed. The structural length of the shut-off valve is longer than that of the gate valve, and the fluid resistance is large, and the sealing reliability is not strong during long-term operation.
1 In the closed position, the valve body is mechanically pressed by the valve stem, and the sealing surface of the valve clack is tightly pressed on the valve seat.
2 When turning the handwheel counterclockwise, the valve stem moves in the opposite direction, and the bottom angle plane makes the valve body separate from the valve seat.
3 The valve stem continues to lift, and interacts with the guide pin in the spiral groove of the valve stem, so that the valve flap starts to rotate without friction.
4 Until it reaches the fully open position, the valve stem is raised to the limit position and rotated to the fully open position.
Parameters of electric shut-off valve:
Valve material: cast iron, cast steel, stainless steel, forged steel, forged stainless steel, chromium molybdenum steel, low temperature steel.
Working pressure: 1.6-32MPa
Working temperature: -196°C-550°C
Valve diameter: DN15-DN800 Connection method: flange, wire or welding
Drive mode: electric
Applicable medium: water, oil, gas, steam, etc.
Application areas: mechanical equipment, chemical equipment, general parts, industrial equipment, water supply and drainage equipment, papermaking equipment, pharmaceutical equipment, general equipment, petrochemical equipment, power equipment, metallurgical powder equipment, mining equipment, municipal, electronic industry, etc.

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: The working principle and characteristics of the globe valve; The difference and selection of electric valve and pneumatic valve; 

bellows globe valve structure and features

Bellows globe valve structure (picture), the function and characteristics of bellows globe valve
Bellows globe valve structure:
Bellows cut-off valve is mainly filled with a bellows seal. The upper part of the outer surface of the bellows is welded to the valve body to form a closed space in which the liquid is contained. The valve stem is inserted into the bellows, and the bottom of the bellows is connected to the valve core. The expansion and contraction of the bellows controls the opening of the valve core. Therefore, if the bellows does not crack, there can be no leakage. The bellows has a very high sealing reliability and can be used in toxic media or gases. Such as chlorine. Prevent leakage.

Globe valve (9)

Globe valve (9)

Structural characteristics of bellows globe valve:
1. Double sealing design (bellows + packing) If the bellows fails, the stem packing will also avoid leakage and meet international sealing standards
2. There is no fluid loss, reducing energy loss and improving plant equipment safety
3. Long service life, reduce maintenance times and lower operating costs
4. Rugged and durable bellows seal design to ensure zero leakage of the valve stem and provide maintenance-free conditions
5. The gas medium valve seat adopts PTFE soft sealing material to improve the sealing performance of this valve
6. High temperature resistance≤425℃The valve seat adopts conical hard seal. Achieve airtight performance and zero leakage

The function of the bellows globe valve:

The function of the bellows in the globe valve is to seal and prevent the medium from leaking from the valve stem. The lower end of the bellows and the valve stem are connected by sealing welding, the upper end and the gland are connected by sealing welding, and the gland is connected with the upper Metal spiral wound gaskets are generally installed between the flanges to ensure sealing. The bellows shut-off valve is extremely tight and rarely leaks.

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:
The structure and characteristics of bellows gate valve;
bellows globe valve vs ordinary globe valve;
Comparison of bellows globe valve and ordinary globe valve
The working principle and characteristics of the globe valve

Pneumatic globe valve model preparation method

Pneumatic globe valve /cut-off valve model preparation method
Pneumatic shut-off valve is used to open and close the pipeline medium by compressed air, and the action speed is relatively faster. Different materials and seals are selected, which can be applied to various pressure, temperature

and medium conditions, and the seal is reliable and the performance is excellent. However, since there are many types of pneumatic stop valves and their structural forms are changeable, users should be familiar with their model designation method when choosing pneumatic stop valves, so as to avoid problems such as selecting the wrong type, replacing goods and returning goods!
Pneumatic globe valve model preparation instructions are represented by the code of the globe valve type, drive mode, connection mode, structure form, sealing material, nominal pressure, valve body material, etc., mainly for the model description of the existing pneumatic globe valve products, such as customized When the material and structure of the globe valve products change, please select according to the valve preparation method.
Pneumatic shut-off valve model preparation method:
Additional code for stop valve: W means bellows, D means low temperature, B means heat preservation;
1) Type code of globe valve: J means globe valve;
2) Stop valve transmission mode: manual without code, 5 bevel gear, 6 pneumatic, 9 electric;
3) Connection mode of stop valve: 4 flange connection, 6 welding;
4) The structure of the globe valve: 1 straight-through type, 2 Z-type straight-through, 3 three-way, 4-angle type, 5 Y-type DC type, 6 balanced straight-through type, 7 balanced angle type, 8-pin type;
5) Seal material of globe valve: F fluorine rubber, H stainless steel, N nylon plastic, Y cemented carbide, M Monel alloy, W valve body directly processed;
6) The nominal pressure of the shut-off valve: 16 means that the pressure of 1.6mpa is 16 kilograms, PN1.6-32mpa, IN150LB-1500LB, 5-63K;
7) Globe valve body material: A titanium alloy, C carbon steel, I chromium molybdenum steel, P stainless steel 304, R stainless steel 316;
Examples for the compilation of pneumatic shut-off valve models:

pneumatic globe valve

pneumatic globe valve

WJ641H-16C Pneumatic Bellows Globe Valve
1. W: means bellows
2. J: represents the stop valve;
3. 6: indicates that the transmission mode is pneumatic;
4. 4: The connection method is flange connection;
5. 1: The structure is a straight flow channel;
6. H: Hard seal made of stainless steel for the sealing pair;
7. 16: Indicates that the nominal pressure is 1.6MPa;
8. C: Indicates that the valve body material is carbon steel.

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: The working principle and characteristics of the globe valve; 

bellows globe valve vs ordinary globe valve

The difference and comparison between bellows globe valve and ordinary globe valve
The bellows globe valve is also called the bellows seal globe valve. Through automatic seam welding, a metal barrier is formed between the fluid medium and the atmosphere to ensure the design of zero leakage of the valve stem. Compared with traditional globe valves, it has the following advantages:

Globe valve (9)

Globe valve (9)

1. The bellows globe valve has a long service life, reduces the number of maintenance and lowers operating costs. The sturdy and durable bellows seal design ensures zero leakage of the valve stem and provides maintenance-free conditions.
2. The valve opening and closing torque is small, reducing labor intensity, and can drive any form of driving device, which is convenient for remote control.
3. The appearance is beautiful, the valve channel has a smooth streamline, and the flow resistance coefficient of the valve is reduced. It is a high-quality energy-saving product.
4. The outer seal of the valve adopts bellows seal and graphite, stainless steel gasket seal, the seal is reliable, and the sealing packing does not need to be replaced for long-term use. In industrial use, the leakage caused by the stop valve: high temperature, highly toxic, flammable and explosive, radiant medium, etc., not only pollute the environment, but also often cause significant personal and property losses. However, this type of valve is much safer and more stable, and strictly adopts foreign advanced standards in design and manufacturing.

Advantages and application of bellows globe valve The bellows globe valve has no leakage, and it is safer to be used in high-risk media. Ordinary globe valve is sealed with packing, the valve stem and packing will slide, and it is easy to leak at low temperature (spool).
The bellows cut-off valve uses a closed bellows that can be stretched and compressed to replace the packing seal, which can effectively prevent external leakage caused by packing loss. It is generally used for the transmission of highly permeable media, such as valves on hydrogen systems, as long as the bellows is not damaged, there is generally no leakage; while the general shut-off valve is sealed with packing, which is prone to leakage.
The opening or closing stroke of the valve stem of this kind of valve is relatively short, and it has a very reliable cut-off function. Also, because the change of the valve seat port is proportional to the stroke of the valve disc, it is very suitable for flow adjustment. Therefore, this type of valve is very suitable for use as a shut-off or adjustment and throttling.

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: The structure and characteristics of bellows gate valve; Comparison of bellows globe valve and ordinary globe valve; 

Characteristics and working principle of electric globe valve

Features of electric globe valve:

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

    Globe valve (9)

    Globe valve (9)

  • Simple structure, small size and light weight. Electric globe valve
  • It is tight and reliable. The sealing surface material of the gate valve is widely used plastic, and it has good sealing performance. It has also been widely used in vacuum systems.
  • 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.
  • The maintenance is convenient, the gate valve has a simple structure, the sealing ring is generally movable, and it is convenient to disassemble and replace.
  • When fully open or fully closed, the sealing surface of the ball and the valve seat is isolated from the medium, and the medium will not cause erosion of the valve sealing surface when the medium passes.
  • It has a wide range of applications, with a diameter ranging from a few millimeters to a few meters, and can be applied from high vacuum to high pressure.

Electric globe valve classification:

According to its channel position, it can be divided into straight-through type and right-angle type.

Working principle of electric globe valve:

The working principle of the electric shut-off valve is to make the valve unblocked or blocked by rotating the valve. The gate valve switch is light, small in size, can be made into a large diameter, reliable in sealing, simple in structure, convenient in maintenance, the sealing surface and the spherical surface are often closed, and it is not easy to be eroded by the medium. It is widely used in various industries.

A. Opening process of globe check valve:

  • In the closed position, the valve body is pressed against the valve seat by the mechanical pressure of the valve stem.
  • When the hand wheel is turned counterclockwise, the valve stem moves in the opposite direction, and the angular plane at the bottom causes the ball to separate from the valve seat.
  • The valve stem continues to lift and interacts with the guide pin in the spiral groove of the valve stem, so that the ball begins to rotate without friction.
  • Until it reaches the fully open position, the valve stem is raised to the limit position, and the ball rotates to the fully open position.

B. Closing process of electric globe valve:

  • When closing, turn the handwheel clockwise, the valve stem begins to drop and the ball leaves the valve seat to start rotating.
  • Continue to rotate the hand wheel, and the valve stem will be acted on by the guide pin embedded in the upper spiral groove to make the valve stem and the gate rotate 90° at the same time.
  • When it is about to close, the gate body has rotated 90° without contact with the valve seat.
  • In the last few turns of the handwheel, the angular plane at the bottom of the valve stem mechanically wedges and presses the sphere to make it tightly press on the valve seat to achieve a complete seal.

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:
Characteristics of ball valve;
The working principle of butterfly valve (picture);
Electric ball valve principle | Electric ball valve working principle;
Working principle of electric gate valve