Are you worried about the leakage of the bellow seal valve? And looking to control valve leakage and regulate the flow of pressure? If so, you are on the right site. In this post, you will learn bellow seal valves, their benefits, advantages, analysis, and more. So let’s connect.

When select and installing a suitable valve lowers the risk of harmful chemicals causing damage to any surrounding environment. Due to advances in chemical industries, many kinds of hazardous and toxic fluids pass through pipelines, bellow seal globes are used. Dangerous materials such as ammonia, hydrogen, chlorine, and other material are handled. So it is essential to keep a liquid or gas inside a system; consider a bellows seal valve. Bellow seal valves are welded in carbon stainless steel to avoid system damage.

What is the bellow seal valve?

A Bellow Sealed Valve is an industrial operation valve designed to control leakage. And is also termed as ‘Emission Free Valve’ or ‘Zero Leak Valve.’ It has a unique designed valve suitable for use in places dealing with a hazardous medium. And that sites where small leakages can result, are critical. Bellow seal valves use in piping structures to control leakage.

How To Use Globe Valves?

Bellow seal globe valves are designed for use in places with hazardous materials and where a throttling item is required. An important feature of the globe valve is keeping the valve core parallel to the flow line. This feature makes the globe valve more effective when throttling, yielding minimal disc. This s-shaped design, yet, makes resistance within the valve.

Body structure

The globe valve body’s structure helps the item flow to change direction within the valve itself. The change in direction generates pressure on turbulence. In most installations, the commodity is routed into the valve’s body below the valve seat and disc. This flow direction uses pressure to help reduces wear on the valve seats and disc.

One exception is when high-temperature steam is passed via the valve. The high temperature of the steam on the valve seat creates a temperature comparison. So high temperature causes the metal of the disc to leak. It should be used where external leakage of method fluids impacts people, the environment, and plant performance.

Examples of typical applications for the bellow sealed globe valve are;

• Phosgene
• Ethylene

Here are some benefits of using the bellow values:

• It lowers the loss of material fluid and provides safety or external protection. It also improves the safety of the area where it has been installed.
• The bellows valve has two seals in good condition; the packing is fine or extends its service life from the medium.
• It can reach zero leakage and is emission-free. Which is reliable or safe from helium mass spectroscopy. Before installation, every bellow valve is tested for zero leakage using a helium gas mass spectroscopy.
• The steam valve has a metal barrier used in specific conditions, such as oxygen the valve.
• It works both the expansion and contraction, which is not affected by contraction. It has very prominent benefits where the temperature slope of the medium is enormous.

How to install a bellow seal valve?

Here are the installation methods for bellow seal valves, which you can install in any position. Do not install bellow seal valves with stem upside down to prevent pollution deposition. Before installation, ensure all pipes do not have any tension on the valve body. So make sure all pipes have clean and have no impurities. The pipes must be joined so that there would not be any force acting on the valve’s housing.

Advantages of a Bellow Seal Valve

Unlike any ordinary globe valve, the design of the bellows seal globe valve is much better. As a pressure pipe, the valve controls the connection of the fluid in the pipeline. Once it damages, results are unimaginable, and the system shuts down for maintenance. So, the life or quality of the bellow vale is so important. So, here are some advantages of bellows seal globe valves:

Easily applicable

Bellow globe valve has easily applied to high-risk medium and has no leakage. To replace packing seals, use closed bellows, which can be expanded and compressed. By expanding, they will prevent leakage caused by packing losses. So, they use for transmission of medium with effective permeability. For example, no leakage appears in the hydrogen system, as long as the bellows are not damaged.

Ideal system

The bellows seal globe valve stem is short and can cut off the media flow by opening or closing the stroke valve. The valve is ideal for flow regulation due to the fluid opening change to the disc’s stroke. So, this type of valve is very suitable for throttling and regulating the flow. The functional safety improves with the installation of a bellows valve as producing chemicals.

Case Analysis And Improvement Method Of Bellows Globe Valves Caused The Failure

Problem analysis

Bellow Seal Globe Valve leakage is generally divided into two types of leakages. These are external leakage and internal leakage. Endocrine occurs due to the failure of the closing surface caused by the liquid sample. The reason for the leakage of the valve stem is the working environment, structure, and operation mode of the valve.

Structure

The valve stem has a double sealing structure below. The bellows are connected with the inner and outer lining ring to form a bellows collection. Then welded with the valve stem of the medium through the valve stem. The valve system shows two directional movements, upward or downward. These directions go from the flat key until the upper surface contact with the lower surface.

 If these movements exceed the limit, bellow may fail and rupture the small pipe seal. Improving the limit device for opening or closing the valve is important. So, movements of the valve will be according to the design opening or closing procedure of the valve.

Working environment

The other failure reasoned the harsh working environment of carbon steel stainless steel. Because the vessel body operating in salt spray conditions for a time caused corrosion of the upper thrust ball bearing.

Operation

When the valve is opened overly, the bellows assembly may be operated, causing the globe valve to leak. When the valve is closed overly, causing the seal to fail when the valve is used again. Improve After examining the valve issues, the operation, structure, and environment were improved. The first is to raise the limit welfare fee of the flat key.

Movements

 If these movements exceed the limit, bellow may fail and rupture the small pipe seal. Improving the limit device for opening or closing the valve is important. So, movements of the valve will be according to the design opening or closing procedure of the valve.

Installation

When the valve can’t shut off, it should not exist to close. Rather, you should unplug the valve. Then washed with liquid for a specific period, dried, and closed again. If it still can’t be closed, examine the ground sealing surface. Do not try to continue to move the valve to extend until the globe valve is opened to a specific height. And the valve stem faces a slight resistance. During installation, prevent the direct drop of condensed water on the valve because it will cause the valve stem to rust.

Summary

Using bellow seal globe valves successfully minimizes the risk of any leakage. Covering the condition of the valve’s stem with a bellow prevents leakage. The basic design of the Bellows Seal Globe Valve makes it the best valve for various applications. They find especially in hazardous materials & where system media is at high temperatures. The benefits of bellows seal global valves are maintenance-free operations, durability, and cost-effectiveness. In all the above, we have explained below the seal globe valves, benefits, causes, and improvement of valves.