Carbon Steel Gate Valve: The Ultimate FAQ Guide

This guide covers all information you’re looking for about carbon steel gate valve.

So before investing in your next carbon steel gate valve, read this guide.

What Is The Function Of Carbon Steel Gate Valve?

Carbon Steel Gate Valve

A carbon steel gate valve limits the media’s flow by lifting the gate to open and lowering it to close.

The distinctive feature of a carbon steel gate valve is its unobstructed passageway, and it induces very minimum pressure loss on the valve.

The unobstructed bore of the carbon steel gate valve makes it easy to clean pie procedures compared to other valve types.

Carbon steel gate valves need to be either open or closed fully not to regulate flow.

Applications of carbon steel gate valves include Petrochemical plants and refineries, which use low pressure.

It is maximum utilized in upstream facilities as they require a very high operating pressure and long opening and closing times.

How Many Types Of Gate Valves Are There?

There are several types of gate valves, some of which are classified in three main ways as shown below:

Type Of Body Bonnet Joint

1. Screwed bonnet: it is one of the most common designs around and serves valves that are not expensive.
2. Bolted bonnet: it serves in very many designs of gate valves, and it needs a gasket for sealing the joint positioned between the body and bonnet.
3. Welded bonnet: this design does not need disassembly and is light in weight compared to other types.
4. Pressure seal bonnet: it is applied mainly for applications of high temperature and high pressure.

Types Of Disk

1. Solid taper wedge gate valve: it is solid and straightforward, and suited for almost all fluids.
2. Flexible wedge gate valve: it is a hard disc of one piece and has a perimeter that cuts around. The cuts on this gate valve vary in size, depth, and shape.
3. Split wedge or parallel disks gate valve comprises two solid pieces and can hold together using a unique mechanism.

Types Of Stem Movement

1. Rising stem gate valve: in this, the stem goes up when the valve is opened and moves down when it is closed.
2. Non-rising stem: it does not contain upward movement as the valve disk is internally threaded.

Which Are The Different Gate Designs Of Carbon Steel Gate Valve?

Some of the different gate designs of carbon steel gate valves include:

• Wedge gates: It contains a wedge form and positions on two seats that are inclined. The primary force which forms by the pressure of the fluid helps in sealing.

The sealing of the carbon steel gate valve adds wedging force on the seats due to the tightening of the stems.

Wedge Gate Valve

• Parallel slide gates: Makes up a flat rate and parallel seats, and it uses line pressure in making the seal tight to control pressure.
• Slab gates: They possess a hole the size of a bore, and when open, the bore is in line with two seat rings. The alignment of slab gates results in a bit of turbulence and ensures smooth flow.
• Parallel expanding gates: They possess two slabs that match together to offer sealing through mechanical expansion of the gate. When they raise, they make it possible for media to flow through and ensure a proper seal.

The upward pressure on one slab and the inhibition by the second slab through a step in the valve’s body enables mechanical expansion outwards. This aspect of mechanical expansion makes it possible for the gate to have a proper seal.

Parallel Expanding Gates

• Knife gates: Utilized for fluids that are thick and solids that are dry and bulky. They comprise one metal piece that points and self-cleaning because they pass seat rings in opening and closing processes.

Knife Gate Valve

Which Are The Main Components Of Carbon Steel Gate Valve?

The main components of carbon steel gate valve include:

• Seat: These are either provided together with the valves or come in a type of connection that is a seat ring construction. This construction puts a pressed or threaded seat into position then welded into the valve’s body.
• Body: It is connected to other parts of the carbon gate valve through flanged, welded, or screwed connections.
• Stem: It ensures that the disk positions properly and is well connected to the handwheel. Stems are typically connected and forged to the disk using threaded technique or any other available technique.

They categorize into the rising stem and non-rising stem.

• Actuator: They open and close the carbon steel gate valve in response to either manual or automatic manipulation.
• Bonnet: It possesses moving parts of the carbon gate valve. It is fixed to the body of the carbon gate valve by a bolt to make maintenance easy.

How Do You Install A Carbon Steel Gate Valve?

Carbons steel gate can be installed in any orientation, but it is recommended to install it upward for bigger sizes. It will ensure more accessible access to the handwheel.

It is essential to verify all the carbon steel gate valve materials to ensure they do not possess any defects that may affect their performance.

Ensure that there is no misalignment or warpage of its flange to avoid problems in the carbon steel gate valve.

Install the bolts for spacing while ensuring that damage is not caused to the valve seat.

Ensure enough space to have the valve in and out of service by adjusting the face to face of the two flanges.

Once the pipes are at the centre, fit in the bolts so that the valve is positioned on them to inhibit them from falling.

The bolts are then tightened one by one in stages. It ensures pressure, which forms a seal between the gasket, flange, and valve.

Once you have completed the carbon steel gate valve installation, the test is done by operating it several times. It will ensure that it did not move during the installation process.

What Is The Working Principle Of Carbon Steel Gate Valve?

Carbon steel gate valve it operates in a straightforward mechanism. When the handwheel of the carbon steel gate valve turns, it rotates the stem and then moves it up or down using threads.

Carbon steel gate valves need more than 360 degrees to turn entirely and open or close the valve. In this way, the gate lifts from the flow’s path, and the carbon steel gate valve opens.

When it lowers to a closing position, the bore seals, thus closing the carbon steel gate valve fully. For a carbons steel gate valve, its vertical travel relationship to that of the flow rate is nonlinear, and the highest variations occur near the shutoff.

When a carbon steel gate valve regulates the flow, the high velocity at partial opening causes wears at the gate and seat.

Which Is Better Between Carbon Steel Gate Valve Vs. Stainless Steel Gate Valve?

Despite carbon steel gate valve and stainless-steel gate valve being made of similar materials, they have some distinguishing factors, which include:

Stainless Steel Gate Valve

It possesses a very high resistance to rusts and stains due to corrosion because its nature is designed to protect against oxidation. It is because it is an iron alloy that is mixed with nickel and chromium.

The nature of stainless-steel material ensures that the stainless steel gate valve can control leaks. Stainless steel gate valve is also able to function in more temperatures compared to carbon steel gate valve.

They serve as the best options in areas of high pressure and temperature.

Stainless Steel Gate Valve

Carbon Steel Gate Valve

It contains a high level of carbon of about 2.1 per cent, which can change the characteristics of steel in the valve.

It is because the carbon in the carbon steel gate valve makes it more robust and harder.

However, the carbon steel gate valve lacks corrosion resistance properties compared to the stainless steel gate valve.

Therefore, although it is durable than stainless steel gate valve, it may be subject to rust and corrosion when exposed to moisture.

Carbon steel gate valve

What Is The Difference Between Double Expanding Gate Valve Single Expanding Gate Valve?

Some of the differences between a double expanding gate valve and a single expanding gate valve include:

• Double expanding gate valves possess two half disks and isolate the piping system or components when closed.
• The single expanding gate valve expands only in the closed position, and these seals the two seats.
• For the double expanding gate valve, the cavity does not fill in both closed and open positions.
• A double expanding gate valve is relatively expensive as compared to a single expanding gate valve.

How Do You Open And Close Carbon Steel Gate Valve?

The carbon steel gate valve opens by turning the handle gently to the left without excess pressure.

As soon as you feel any resistance when opening the carbon steel gate valve, it would help if you stopped immediately.

It is because turning it with excessive pressure can damage the system and even result in leakages.

The carbon steel gate valve is closed by turning it to the right gently.

Application of excess pressure when closing the carbon steel gate valve may cause it to bend, thus leading to permanent damage to the seal and seat.

What Are The Advantages And Disadvantages Of The Carbon Steel Gate Valve?

Some of the advantages of carbon steel gate valves include:

• It requires little maintenance.
• It can be utilized in vales that are bi-directional.
• The costs of purchasing, installation, and functioning of carbon steel gate valves are relatively low.
• Carbon steel gate valves are available in several size options.
• They ensure shallow frictional loss because they possess a low-pressure drop.
• Carbon steel gate valves offer good characteristics of shutting off.

Some of the disadvantages of carbon steel gate valves include:

• Carbon steel gate valve cannot be utilized for throttling service.
• It is difficult to carry out grinding and lapping repairs.
• When the carbon steel gate valve opens partially, it may make noise and vibrations.
• It takes a little longer in closing and opening due to the slow movement of its disk.
• The carbon steel gate valve may be subject to wear of the seat and disk.

Which Are The Carbon Steel Gate Valve Media?

The media for carbon steel gate valve include:

• Liquid services
• Gas services
• They are suited for slurries with entrained solids, powders, and granules.
• Cryogenic services
• Vacuum services

How Does The Bonnet And Trim Of Carbon Steel Gate Valve Compare?

The bonnet of a carbon steel gate valve possesses moveable parts, and it connects to the valve body.

It is removable from the body of the carbon steel gate valve to allow for easier replacement of parts and maintenance.

The trim of a carbon steel gate valve possesses the valve’s functioning units: the gate, stem, wedge, seat rings, and discs.

When Should You Use By-Pass Carbon Steel Gate Valve?

It would be best if you used a by-pass carbon steel gate valve for the following reasons:

• When there is a delay in filling pipelines system
• To allow differential pressure in pipelines to balance in a way that lowers the torque requirement of the valve. It will give a permit to operate by one man.
• When the main valve is closed, the by-pass is open to allow a continual flow, eliminating the possibility of stagnation.

What Is The Difference Between Metal Seated Carbon Steel Gate Valve Vs Resilient Seated Carbon Steel Gate Valve?

Some of the differences between metal seated carbon steel gate valve and resilient seated carbon steel gate valve include:

Metal Seated Carbon Steel Gate

Metal seated carbon steel gate valves possess a conical wedge design and sealing angular devices. They need a depression at the bottom of the valve for closing tightly.

The pipe system in the metal seated carbon steel gate valve always contains impurities as sand pebbles get embedded in the bore.

Due to this, the metal seated carbon steel gate valve loses the ability to be very tight over time.

Resilient seated carbon steel gate vale contains a valve bottom that is simply making way for sand and pebbles.

In case impurities pass through during the closure of the valve, the rubber surface closes around them while the valve remains closed.

Resilient Seated Carbon Steel Gate Valve

Rubbers of high quality and regain their original shape can absorb any impurities during the closure of the valve.

When the valve opens, the impurities are flushed away.

How Do You Disassemble Carbon Steel Gate Valve?

Carbon steel gate valves tend to be screwed between two pieces of piping or to a wall.

It would be best to try unclogging the valve by putting water in the system before removing it.

It would help if you did this by turning on the water source at a very high rate, then open it and close it slowly till it reaches the end; this will make it possible to loosen some debris and allow for complete closure of the carbon steel gate valve.

If this does not work, turn off the water source and eliminate the valve from the pipeline. You will do this by removing screws from the ends.

Once the carbon steel gate valve is disconnected, you should use pliers to loosen its bonnet. However, please do not make the packing nut lose because it holds the components together and prevents leaks.

When you have removed screws from the bonnet, it will be possible to set apart the top of the carbon steel gate valve.

The top will also contain the seating and handle from the body.

You will now be able to clean the carbon steel gate valve very well from its top by using the cleaning tools of your choice.

Which Are The Common Stem Design Of Carbon Steel Gate Valve?

Standard stem designs of carbon steel gate valves include:

• Rising stem: It is fixed onto the gate and can rise and lower during the operation of the valve. It provided a clear view of the position of the valve and enabled easy greasing of the stem.
• Non-rising stem: It is threaded to the gate vales and can rotate as the wedge rises and lowers in the valve. It occupies little space vertically because the stem is located at the body of the valve.

Can You Automate Carbon Steel Gate Valves?

Yes, there are carbon steel gate valves that are automated as they have electrical actuators. However, they are not cost-effective.

Carbon steel gate valves that are automated are frequently used when it is difficult to access and operate gate valves.

Automated carbon steel gate valves use actuators extensively.

Which Codes And Standards Dictate The Design Specification Of Carbon Steel Gate Valve?

Some of the codes and standards that dictate the design specifications of carbon steel gate valves include:

• API 600
• API 602
• BS5352
• API 603
• API6D/IS780
• BS 1414
• BS 14846
• API 589
• API B16.34
• ANSI B16.10
• 5
• ASME B 16.47
• BS 10
• DIN standards
• JIS standards
• ANSI B26.25
• ANSI B16.11
• ANSI B 1.20.1

How Does Carbon Steel Gate Valve Vs Ball Valve Compare?

Carbon steel gate valve compares to ball valve in the following ways:

• Working principle: The carbon steel gate valve controls the valve by using its gate so that when lifted, total flow is allowed and vice versa. Ball valve contains a ball that has an opening which, when lined up with the pipe by turning the control lever, fluids pass.
• Weight: ball valves tend to weigh more than carbon steel gate valves.
• Cost: Carbon steel gate valves are relatively affordable as compared to ball valves.
• Turning of lever or handwheel: The carbon steel gate vale turns the lever or handwheel in a multi-turn, while the ball valve uses a quarter-turn.
• Shut off capabilities: Ball valves exhibit better shut off capabilities compared to carbon steel gate valves.
• Surge probability: Carbon steel gate vales have less probability of water hammer because their operation is slow. Ball vales are highly prone to the creation of a surge of water hammer.
• Variation probability: In a carbon steel gate valve, vibrations may come about if the gate is open partially, while ball valves exhibit minimal vibrations.
• Operating space requirement: Ball valves required more operating space as compared to carbon steel gate valves.

Ball Valve

What Is An OS &Y Gate Valve?

An OS &Y Gate Valve

The operation of OS and Y is by opening and closing through a gate valve that arises out of or lowers into the valve.

Raising the gate valve enables water to flow via the valve, and gate cuts are eliminated from the water flowing via the valve.

The OS and Y gate valve is attached to a threaded stem with a handle that links to the yoke element. When the handle rotates counterclockwise, the stem raises the handle and opens the gate.

When rotated clockwise, the stem moves back, and the valve will close. The gate valve is closed fully when the stem is not protruding beyond the handle.

Can You Throttle Carbon Steel Gate Valve?

Because carbon steel gate valves tend to valve for isolation, they need to be either fully closed or fully open.

They must not be used to regulate the flow of water thus are not suitable for throttling a flow.

When a carbon steel gate valve is used in such a case, vibrations can result from turbulent flow rates via the valve body.

It may damage the seat and wedge, eventually causing leakages in the carbon steel gate valve.

What Are Some Of The Maintenance Guidelines For Carbon Steel Gate Valve?

Some of the maintenance guidelines for carbon steel gate valves include:

• You should cycle the carbon steel gate valve at least once a month if it is not used regularly.
• Replace the valve’s gate by removing the bonnet and stem, then screwing the gate out to replace the new element.
• Before carrying out any maintenance on the carbon steel gate valve, you should remove the pressure in the system.

Which Are The Important Considerations During Operation Of Carbon Steel Gate Valve?

Some of the essential considerations during the operation of carbon steel gate valve include:

• It would help if you never let the carbon steel gate valve function at a pressure higher than its working pressure.
• If the carbon steel gate valve is jammed in between open and closed positions, inspect its seat and face. You should remove it and inspect if there are any foreign objects.
• The internal parts of the carbon steel gate valve get destroyed by excessive torque emanating from actuators.

What Is The Role Of Pressure-Equalization Connection In Carbon Steel Gate Valve?

The pressure equalization connection links the chamber of the valve to piping that is upstream. It is used in carbon steel gate valves that handle fluids with high thermal expansion.

When the carbon steel gate valve operates, thermal expansion of trapped fluids forcer disks collide. The upstream and downstream disks might come into very close contact with their seats, making pressure in the carbon steel gate valve rise.

It may result in leakages in joints and bonnets due to higher seating stress if pressure equalization connection is not utilized. Pressure equalization connection is granted by internal or external means or a hole in the disk located upstream.

How Much Does A Carbon Steel Gate Valve Cost?

The price of carbon steel gate valve tends to range between $500- $2000 depending on several factors such as:

• Design of the carbon steel gate valve
• Sizing of the actuator
• Method of installation
• Accessories required

At Kinvalve, we design and manufacture a range of carbon steel gate valves.

We can also support your OEM business – contact us now for all your carbon steel gate valves.