Medium of initial conditions, the valve closed pipe into the valve body, with big holes on the disc into the disc lumen, start the drive, the stem drive small disc first open, open the seal, medium through a small disc, the valve on both ends of the differential pressure decreases rapidly, continue to open small disc until fully open) (about a third of the valve, the valve stem continues to rise to drive the disc open, open the seal, and valve fully open. The stem force of the force needed to open a small disc and the function of the medium on the large disc force (gravity negligible), the small disc opens, the pressure differential between the valve import and export decrease (mainly depends on sealing area ratio between inside and outside), the open large disc, medium forces acting on the large disc far less directly using single disc medium forces acting on the disc, the valve stem of total force decreases, and the stem diameter smaller, lumen size smaller, the overall structure of the valve is reduced, the weight, and at the same time open the valve drive thrust decreases, and at the same time reduces the valve and a driving gear manufacturing costs, Improve the use economy of the valve to achieve the purpose of energy saving.

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Structural difference between gate valve and globe valve

In the case of limited installation space, attention shall be paid to the selection. The gate valve can be tightly closed with the sealing surface depending on the medium pressure, so as to achieve the effect of no leakage. If the valve core is in contact with the sealing surface of the valve seat and there is the friction when opening and closing, the sealing surface is easy to wear. When the gate valve will be closed, the pressure difference between the front and back of the pipeline is large, which makes the sealing surface wear more seriously. The structure of gate valve will be more complex than globe valve. From the appearance, under the same caliber, gate valve is higher than globe valve, and globe valve is longer than gate valve. In addition, gate valves are divided into open stem and concealed stem. Globe valve cannot be divided.

Working principle of globe valve and gate valve

When the globe valve is opened and closed, it is rising stem type, which means, turning the hand wheel will rotate and lift along with the stem. The gate valve rotates the hand wheel so that the stem move up and down, and the position of the hand wheel remains unchanged. The flow rate is different. The gate valve is required to be fully open or fully closed, while the globe valve is not required. The globe valve has specified inlet and outlet directions; the gate valve has no requirements for inlet and outlet directions. In addition, the gate valve only has two states: full open or full close. The stroke of gate opening and closing is very large, and the opening and closing time is long. The movement stroke of the valve plate of the globe valve is much smaller, and the valve plate of the globe valve can be stopped at a certain place during the movement for flow regulation. The gate valve can only be used for truncation without other functions.

Performance difference between gate valve and globe valve

Globe valve can be used for cut-off and flow regulation. The flow resistance of the globe valve is relatively large, and it takes time to open and close. However, the distance between the valve plate and the sealing surface is short, so the opening and closing stroke is short.

Installation and flow direction difference between gate valve and globe valve

In terms of flow direction of gate valve, the effect is the same in both directions. There is no requirement for the direction of inlet and outlet for installation, and the medium can flow in two directions. The globe valve should be installed in strict accordance with the direction indicated by the arrow of the valve body. There is a clear regulation on the direction of the inlet and outlet of the globe valve. According to the “serialization, universalization and standardization” of China’s valves, the flow direction of the globe valve should be from top to bottom.

From the perspective of flow resistance, when fully open, the flow resistance of gate valve is small and that of load check valve is large. The flow resistance coefficient of ordinary gate valve is about 0.08 ~ 0.12, the opening and closing force is small, and the medium can flow in two directions.

The cut-off valve is low inlet and high outlet. From the appearance, it is obvious that the pipeline is not on the same phase horizontal line. The gate valve flow path is on a horizontal line. The stroke of gate valve is larger than that of globe valve. The flow resistance of common globe valve is 3-5 times that of gate valve. The valve element of the globe valve contacts the sealing surface only when it is completely closed, so the wear of the sealing surface is very small. The main flow force is large, the globe valve of actuator is needed, so the adjustment of torque control mechanism should be paid attention to.

There are two methods to install the globe valve: one method is that the medium can enter from the bottom of the valve core. The utility model has the advantages that the packing is not under pressure when the valve is closed, the service life of the packing can be prolonged, and the packing can be replaced when the pipeline in front of the valve is under pressure. The disadvantage is that the driving torque of the valve is large, which is about 1 times of the upper flow. The axial force on the valve rod is large, and the valve rod is easy to bend.

Therefore, this method is generally only applicable to small caliber globe valves (below DN50), and globe valves above DN200 adopt the way of medium flowing in from above. (electric globe valve generally adopts the way that medium enters from above.) The disadvantage of media entry from the top is opposite of that from the bottom.

Sealing difference between gate valve and globe valve

The sealing surface of the globe valve is a small trapezoid side of the valve core (it depends on the shape of the valve core specifically). Once the valve core falls off, it is equivalent to the valve closing (if the pressure difference is large, it will not be closed tight, but the check effect is good). The gate valve is sealed by the side of the valve core ram. If the sealing effect is not as good as the globe valve, the falling off of the valve core will not be equivalent to the valve closing as the globe valve.

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Working principle of globe valve

Generally, the stem of globe valve is rotated and lifted, and the handwheel is fixed on the top of the stem. When the handwheel is rotated clockwise, the stem thread is screwed down, the sealing surface of the disc is in close contact with the valve seat, and the globe valve is closed. When the handwheel is rotated counterclockwise, the stem thread is screwed up, the sealing surface of disc and valve seat is separated, and the globe valve is opened.

Features of globe valve

Advantages of globe valve

a.Compared with the gate valve, the globe valve is simple in structure with only one sealing surface on the valve body and disc. The sealing area is small, no expensive materials are used, with low cost, so the manufacturing process is relatively good, and it is simple to maintain.

Disadvantages of globe valve

• a. The length of the structure is large.
• b.The opening and closing torque is large, and it takes time to open and close. When the valve is closed, the movement direction of the disc is opposite to the action direction of the medium pressure, and the force of the medium must be overcome, so the opening and closing torque is large.
• c.The flow resistance is large. The medium channel in the valve body is tortuous, the flow resistance is large, and the power consumption is large. In the hydraulic device, the pressure loss is particularly obvious. Among all kinds of block valves, the block valve has the largest flow resistance.
• d. The flow direction of the medium is limited. When the medium flows through the globe valve, it can only flow from the bottom to the top or from the top to the bottom at the valve seat channel, so the medium can only flow in one direction and can not change the flow direction.
• e.When the valve is closed, solid particles in the fluid medium may be trapped between the sealing surfaces
• f. Inconvenient installation.

Operation characteristics of globe valve

The sealing form of globe valve is forced sealing. When the valve is closed, sufficient force must be applied to the valve disc to achieve the effect of sealing, and the sealing can be realized only when the specific pressure is sufficient.

Sealing force and medium pressure are on the same axis. When the medium enters from the lower part of the valve disc (low in and high out), the closing torque of the valve is greater than the opening torque due to the opposite direction of the medium pressure and the sealing force, and the maximum stress on the valve rod is the pressure stress, so there must be sufficient strength and rigidity, otherwise the valve rod will be deformed.

Therefore, when the size of the globe valve is larger than DN150 (NPS 6), in order to reduce the operating torque of the valve and reduce the diameter of the valve stem, the medium is usually flowed to the upper part of the valve disc to enter (high in and low out). At this time, the direction of medium pressure and sealing force is the same. Under the action of medium pressure, the valve can be sealed more easily. The closing torque decreases and the opening torque increases, the maximum stress on the valve stem is tensile stress, and the valve stem diameter can be reduced accordingly.

When the globe valve is opened, when the opening height of the disc reaches 25-30% of the nominal size of the valve, the flow has reached the maximum, that is, the valve has reached the full open position, so the full open position of the globe valve should be determined according to the stroke of the disc.

When the globe valve is closed and reopened, it is similar to the forced seal gate valve, that is, after the valve is closed, sufficient operating force shall be applied on the sealing surface to achieve the effect of sealing. Therefore, the closing torque of the valve should be increased to the specified value based on the operating torque. When the valve is opened again, the opening torque of the valve is usually larger than the closing torque due to the influence of static friction, thermal expansion and other factors, thus, the valve can be opened reliably, and it should be considered in the design.

In order to reduce the high impact pressure formed in the opening and closing valve, the globe valve should be operated slowly, in a sense, it should have a rate of change consistent with the flow rate.

The operating torque of the globe valve has the following characteristics:

“Low inlet and high outlet openings”

When “low inlet and high outlet” is adopted, the valve is closed from the fully open position. The resistance that the operating force needs to overcome is the friction resistance of the stem and packing and the thrust caused by the medium pressure on the disc section (axial). With the falling of the valve disc, the pressure difference between the front and the back of the valve disc is formed, which prevents the valve disc from falling, and the resistance will increase rapidly with the falling of the valve disc. With the valve completely closed, exerts a forced sealing force is applied by the valve rod, and the pressure difference between the front and back of the valve disc reaches the maximum working pressure of the medium, at this time, the valve rod bears the maximum closing torque.

During valve opening, medium pressure, or thrust caused by pressure difference between front and back of disc the same as direction of closing valve. However, it should be noted that at the moment of opening, the opening operating torque may exceed the closing torque due to the large static friction torque between sealing surfaces.

“High inlet and low outlet openings”

When “high inlet and low outlet” is adopted, the valve is closed from the fully open position. The above two forces are still needed to overcome the operating force. With the decrease of the valve disc, the pressure difference before and after the valve disc is conducive to the valve closing before the valve is closed.

When the valve is opened, the situation is just the opposite. The thrust caused by the medium pressure and the pressure difference between the front and the back of the disc is opposite to the opening direction of the valve, so the operating torque required for the opening process of the valve is much larger than the closing torque.

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What is a Globe Valve?

Globe valve, also known as the stop valve, belongs to the forced sealing valve. So when the valve is closed, pressure must be applied to the disc so that the sealing surface does not leak. When the medium enters the valve from the bottom of the disc, the resistance to be overcome by the operating force is the friction between the valve rod and the packing and the thrust generated by the pressure of the medium. The force to close the valve is greater than the force to open the valve, so the diameter of the valve rod is larger, otherwise, the valve rod will be bent. The connection mode, it can be divided into three types: flange connection, screw connection, and welding connection. After the appearance of the self-sealing valve, the flow direction of the medium of the globe valve is changed from the top of the valve disc to the valve chamber. Under medium pressure, the force to close the valve is small, while the force to open the valve is large, and the diameter of the valve rod can be correspondingly reduced. At the same time, under the action of the medium, this type of valve is also strict. “Standardization, serialization and universalization” of the value in China stipulates that the flow direction of the globe valve shall be from top to bottom. When the globe valve is opened, the opening height of the disc is 25% – 30% of the nominal diameter. When the flow has reached the maximum, it means that the valve has reached the fully open position. Therefore, the fully open position of the globe valve shall be determined by the stroke of the disc.

How does a Globe Valve work?

The opening and closing parts of the globe valve are plug-shaped discs, the sealing surface is flat or conical, and the disc moves in a straight line along the centerline of the fluid. The movement form of the valve rod includes the lifting rod type (the valve rod is lifted and the handwheel is not lifted) and the lifting rotating rod type (the handwheel is rotated and lifted together with the valve rod, and the nut is set on the valve body). The globe valve is only suitable for full open and full close, and it is not allowed to regulate and throttle.

The advantages of Globe valve are as follows:

• It is simple in structure and it is easy to manufacture and maintain.
• Small working stroke, short opening and closing time.
• Good sealing performance, small friction between sealing surfaces, and long service life.

The disadvantages of Globe valve are as follows:

• The fluid resistance is large, and the force required for opening and closing is large.
• It is not suitable for medium with particles, high viscosity, or coking medium
• Poor regulation performance.

Types of globe valve:

According to the position of the stem thread, the type of globe valve is divided into external thread type and internal thread type. According to the flow direction of the medium, there are straight-through types, direct current types, and angle types. According to the sealing form, the globe valve is divided into packing seal globe valve and bellows seal globe valve. 

ZECO valve supplies a wide range of globe valves. Our popular products include a105 globe valve, flange globe valve, wcb globe valve, etc. If you want to know globe valve price, please feel free to contact us.

Tee Globe Valve

This is the most common body type for a globe valve. The horizontal setting of the seat allows the stem and disk to travel perpendicular to the horizontal line. This design has the lowest coefficient of flow and highest pressure drop. They’re used in severe throttling services, such as in bypass lines around a control valve. When pressure drop is not a concern and throttling is required, this globe valve design is a good solution.

Angle Globe Valve

The third type among globe valve types is the angle globe valve which represents a shift in the configuration of the Z-shaped basic glove valve. The entry and exit ends are located at the right angles. The diaphragm may be a plain flat plate with its ends at right angles. The fluid can flow down more symmetrically than discharge from the ordinary globe with just one turn in 90. The angle body style has a particular benefit as it can be used as both a valve and a pipe elbow. The angle valve closely resembles the ordinary globe for moderate pressure, temperature, and flow conditions.

The angle globe valve can be used to control the slugging effect in fluctuating flow conditions. In terms of fluid mechanics and erosion, the release conditions of the angle valve are favorable. In high-pressure applications, these features are extremely important. The valve operates more or less like the Z Shaped Valve under mild conditions.

Y Type Globe Valve

The Y-type design is a solution for the high-pressure drop problem in Z-type valves. In this type, the seat and stem are angled at approximately 45° to the pipe axis. Y-body valves are used in high pressure and other critical services where pressure drop is concerned.

Structure of Globe valve body:

The structure of globe valve body includes a straight-through type, straight flow type, and right angle type. Straight through type is the most common structure, but its fluid resistance is the largest. The straight flow type has less resistance and is mostly used for fluid with solid particles or high viscosity. The right-angle valve body is mostly forged, which is suitable for the globe valve with a small diameter and high pressure.

For the installation and maintenance of Globe valve, the following items shall be noted:

• The globe valve of the hand wheel and handle operated can be installed at any position of the pipeline.
• Hand wheel, handle and transmission mechanism are not allowed to be used for lifting.
• The flow direction of the medium shall be consistent with the arrow direction shown in the valve body.

The globe valve has the following advantages:

• In the process of opening and closing, the friction of the sealing surface is smaller than that of the gate valve, which is wear-resistant.
• The opening height is small.
• Generally, there is only one sealing surface, with a good manufacturing process and easy maintenance.

There are many kinds of globe valves, which can be divided according to the position of the thread on the stem:

1. Upper thread stem globe valve

The thread of the globe valve stem is on the outside of the valve body. Its advantage is that the valve stem is not eroded by the medium, and it is easy to lubricate. This structure is widely used.

2. Lower thread stem globe valve

The thread of the globe valve stem is in the valve body. The stem thread of this structure is in direct contact with the medium. It can be easily eroded and cannot be lubricated. This kind of structure is used in small caliber and low-temperature areas.

According to the channel direction of the globe valve, it can be divided into: straight through globe valve, angle globe valve and three-way globe valve. The latter two kinds of globe valves are usually used to change the flow direction of the medium and distribute the medium.

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Globe Valve Types

TEE Pattern/Straight Through Globe Valve

The Tee pattern valve design is the most common type of valve body, which has a 180° inlet and outlet flow path in the same direction and a horizontal setting of the valve seat allowing the stem and disc to move perpendicular to the horizontal line. This design has a low flow coefficient and pressure drop. They are used in severe throttling services such as bypass around control valves.T globe valves can also be used where throttling is required without regard to pressure drop.

Y Type Globe Valve

The stem of the Y type globe valve forms an angle with the valve seat, about 45 degrees. With a straighter flow path at full opening and minimal resistance to flow, it is the least resistant of the globe valves to flow. The sealing surfaces of the seat and flap can be welded with carbide and can be left open for long periods without serious erosion. When used in drains that are normally closed, they can be passed through a rod to remove debris.

Angle Globe Valve

The angle globe valve design is a modification of the basic 3-way shut-off valve. These globe valves have 90-degree angles at both ends and the flow of fluid is only one 90-degree turn, allowing them to be installed at right angles to the piping system, saving the need for 90° elbows. They are used in applications with the pulsating flow as they have the ability to handle the sludging effect of this type of flow. This type of valve is best suited for ammonia production systems and for refrigeration systems in fertilizer plants.

Construction of Globe valves

Globe valves are made up of a valve body, valve disc, valve bonnet, and valve stem. The opening and closing part of the globe valve is a plug-shaped valve disc with a flat or conical sealing surface, which moves linearly along the center line of the fluid. The stem is operated in lift type (the stem is rotated up and down by the handwheel, which remains in its position) and rotary lift type (the handwheel and stem rotate and move up and down together, the lock nut is located on the valve body).

How do globe valves work?

Globe valve is a forced seal valve where pressure must be applied to the disc/plug to establish a tight seal when the valve is closed. When the medium enters the valve from below the valve flap, the resistance to be overcome by the operating force is the friction of the stem and packing and the force generated by the pressure of the medium. When the force to close the valve is greater than the force to open the valve, the diameter of the stem should be increased to avoid distortion and bending of the stem.

With the introduction of the pressure seal globe valve, the direction of media flow in the globe valve is changed from above the valve flap to the valve cavity. In this case, the pressure of the medium will reduce the force of closing the valve and increase the force of opening the valve, so that the diameter of the stem can be reduced accordingly. At the same time, this type of valve is relatively sealed under the action of the medium.

The Function of globe valves in the pipeline system

Conventional globe valves can act as isolators and throttling valves. Although globe valves have a slightly higher pressure drop than straight-through valves (such as gate, plug, and ball valves), they can be used where the pressure drop through the valve is not a controlling factor.

Globe valves are widely used to control flow. The range of flow control, and the pressure drop, must be considered when designing the valve to avoid failure and to ensure satisfactory service. Valves for high differential pressure throttling services require specially designed spools.

In general, the maximum differential pressure across the valve flap should not exceed 20% of the maximum upstream pressure or 200 psi (1380 kPa), whichever is lower. For applications exceeding these differential pressure limits, valves can be designed with special trims.

Performance of Globe Valve

Advantages of Globe Valve

• Good shut-off capability

• Moderate to good throttling capacity

• Shorter stroke (compared to gate valves)

• Available in T, Y and angle patterns, each offering unique features

• Easily machined or resurfaced seats

• Stem not attached to the valve plate, valve can be used as a shut-off check valve

Disadvantages of Globe Valve

• Higher pressure drop (compared to gate valves)

• Greater force or larger actuator is required to seat the valve (pressure below the seat)

• The throttled flow below the valve seat and shut-off flow above the valve seat

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Zeco Valve is a professional globe valve manufacturer.

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The post What is globe valves? The function of globe valve in pipeline system appeared first on ZECO Valve.

What is a Globe Valve?

A globe valve is a linear motion valve that stops, starts, and regulates fluid flow. The globe valve disk can be removed entirely from the flow path, or it will completely close the flow path. During the opening and closing of the valve, the disc moves perpendicularly to the seat.

This movement creates the annular space between the disk and seat ring that gradually closes as the valve closes. This characteristic provides the globe valve good throttling ability required for regulating the flow.

Leakage from the globe valve seat is less as compared to the gate valve, mainly due to right-angle contact between the disc and seat ring, which allows a tighter seal between the seat and the disk.

Globa Valve Function

The globe valve is used for throttling flow control. Shut-off is accomplished by moving the disc against the flow stream rather than across it as in the case with a gate valve. The flow pattern through a globe valve involves changes in direction, resulting in greater resistance to flow, causing a high-pressure drop. The globe valve is an excellent valve to use in the high-pressure operation of steam. Our globe valves are factory-made with quality material for long-term use.

Globe Valve Working Principle

A globe valve is primarily designed to stop, start and regulate flow. It is comprised of a movable disk and a stationary ring seat in a generally spherical body. The seat of a globe valve is in the middle of and parallel to the pipe, and the opening in the seat is closed off with the disk. When the handle is turned, manually or through an actuator, a disc is lowered or raised by means of the valve stem. When the disc is fully lowered, the fluid flow is shut off. When the disc is fully raised, the fluid flow is at its maximum rate. When the disc is in raised to less then maximum level, the fluid flow is regulated with proportion to the vertical travel of the disc.

Globe Valve Types

Body Designs of Globe valves

There are three primary body designs for Globe valves, namely. Tee Pattern or Z-body, Angle Pattern, and Wye Pattern or Y-body body.

• Tee Pattern Globe Valve
  • Tee Pattern Globe valve(T pattern globe valve) design is the most common body type, with a Z-shaped diaphragm. The horizontal setting of the seat allows the stem and disk to travel perpendicular to the horizontal line. This design has the lowest coefficient of flow and higher pressure drop. They are used in severe throttling services, such as in bypass lines around a control valve. Tee-pattern Globe valves may also be used in applications where pressure drop is not a concern and throttling are required.

• Angle Globe Valve
  • The angle Pattern Globe valves(Angle globe valve) design is a modification of the basic Tee Pattern Globe valve. The ends of this Globe valve are at an angle of 90 degrees, and fluid flow occurs with a single 90 degrees turn. They have a slightly lower coefficient of flow than wye-pattern Globe valves. They are used in applications that have periods of pulsating flow because of their capability to handle the slugging effect of this type of flow.

• Wye Pattern Globe Valve (Y Type Globe Valve)
  • Wye Pattern Globe valves(Y-type globe valve) design, is an alternative for the high-pressure drop, inherent in Globe valves. The seat and stem are angled at approximately 45 degrees, which gives a straighter flow path at full opening and offers the least resistance to flow. They can be cracked open for long periods without severe erosion. They are extensively used for throttling during seasonal or startup operations. They can be rod through to remove debris when used in drain lines that are normally closed.

Bonnet Design of Globe Valves

There are three primary bonnet designs for Globe valves, namely.. screwed bonnet, bolted bonnet, welded bonnet, or pressure seal bonnet.

• Screwed Bonnet Globe Valve
  • Screwed bonnet: This is the most basic design possible, and it is utilized for low-cost valves.
• Bolted Bonnet Globe Valve
  • Bolted-bonnet: This is the most common design and is seen in the majority of globe valves. A gasket is required to seal the junction between the body and the bonnet.
• Welded Bonnet Globe Valve
  • Welded-Bonnet: This is a common design that does not need disassembly. They weigh less than their bolted-bonnet equivalents.
• Pressure Seal Bonnet Globe Valve
  • Pressure-Seal Bonnet: This kind is commonly employed in high-pressure, high-temperature applications. The greater the pressure in the body cavity, the greater the strain on the gasket of a pressure-seal valve

Globe Valve Parts

A globe valve has several key parts:

• Bonnet:
  • The bonnet is the outer part of the valve, which encompasses these other parts.
• Cage:
  • The cage surrounds the stem within the valve.
• Stem:
  • The stem connects the disk to the valve actuator or handwheel, transmitting the force.
• Disk (Plug):
  • The part of the globe valve that moves perpendicular to the seat. It’s the moveable physical barrier that blocks (or frees) the flow. When closed, the disk sits against the seat, plugging the flow. When opened, the disk sits above the seat, allowing liquid to pass.
  • Types of Disc
    • Ball Disc – suitable for low temperatures and low pressures. Ideal for starting and stopping operations. Ill-suited for flow regulation.
    • Composition Disc – composites by definition consist of several components. The disc is almost always manufactured from metal whilst a non-metallic ring is mounted onto the disc to form the seating area. The non-metallic ring material is chosen to have good corrosion and erosion characteristics and may be custom-made to ensure it is fit for purpose. If the non-metallic ring is chosen correctly, it should allow for better sealing. Composite discs are often employed for steam system applications.
    • Plug Disc – plug discs have a long and tapered shape. The shape of the plug disc makes it much more suitable to throttling than the composite and ball disc-type designs.
• Seat (Seat ring):
  • This part of the valve provides the seal between the stem/disk and bonnet when the disk is tightly pressed against it. It’s either integrated or screwed into the valve itself.

Globe Valve Symbol

The symbol for a globe valve is two sideways triangles on the same linear line with
the points touching in the middle. Where the points touch, there’s a black circle. You
can see a picture of it here.

For applications with low temperatures, Globe valves are normally installed so that the pressure is under the disc. This contributes to an easy operation and helps protect the packing.

For applications with high-temperature steam service, Globe valves are installed so that the pressure is above the disk. Otherwise, the stem will contract upon cooling and tend to lift the disk off the seat.

Globe Valve Application

The following are some of the typical applications of Globe valves:

• Cooling water systems where flow needs to be regulated
• Fuel oil system where flow is regulated and leak tightness is of importance
• High-point vents and low-point drains when leak tightness and safety are major considerations
• Feedwater, chemical feed, condenser air extraction, and extraction drain systems
• Boiler vents and drains, main steam vents and drains, and heater drains
• Turbine seals and drains
• Turbine lube oil system and others

Advantages and Disadvantages of Globe Valve

• Advantages
  • Good shutoff capability
  • Moderate to good throttling capability
  • Shorter stroke (compared to a gate valve)
  • Available in tee, wye, and angle patterns, each offering unique capabilities
  • Easy to machine or resurface the seats
  • With the disc not attached to the stem, the valve can be used as a stop-check valve
• Disadvantages
  • Higher pressure drop (compared to a gate valve)
  • Requires greater force or a larger actuator to seat the valve (with pressure under the seat)
  • Throttling flow under the seat and shutoff flow over the seat

ZECO Valve is a proessional globe valve manufacturer in China, if any inquiries, please be free to contact us.

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