What is a Top Entry Ball Valve？

The top entry ball valves are the valves that assemble the ball from the top end. This design is similar to a globe valve, featuring a body and a cap, with the distinction being the utilization of a ball-type trim. Unlike globe valves, top entry ball valves are comprised of a single entity.

The top entry ball valves are the valves that assemble the ball from the top end. This design is similar to a globe valve, featuring a body and a cap, with the distinction being the utilization of a ball-type trim. Unlike globe valves, top entry ball valves are comprised of a single entity. Cast metal is commonly used in the construction of top entry ball valves. As it is manufactured through casting, specific additional Non-Destructive Examination (NDE) tests are necessary to verify the absence of defects in the casting process. Top entry ball valves find frequent application in situations where minimal disassembly is needed for in-line maintenance of internal components. These valves are commonly employed in high-pressure systems that require regular upkeep, such as HIPPS (High Integrity Pressure Protection System) valves. The advantage of the top entry Ball Valve lies in its design, which facilitates limited thread interaction, thereby minimizing potential leakage paths.

What Is A Top Entry Ball Valve?

Ball valves are widely utilized in various industries, including oil and gas pipelines, as well as in sectors such as oil refining, petrochemicals, metallurgy, electronics, nuclear, food processing, and paper machinery.

Given the unique environmental and operational conditions of different processes, a standard ball valve may not suffice, and the system often requires a high-performance solution. The top entry structure proves advantageous in this regard, as it eliminates the need to remove the ball valve from the pipeline for seat servicing or replacement, facilitating easy inspection and maintenance.

In a top entry configuration, the seat's location is altered with either a wedge or a threaded seat on the exterior. While an external wedge can enhance external leakage points and compromise sealing efficiency, a threaded seat may undergo rapid wear in large-diameter valves, reducing its service life. To address these challenges, a consistent top entry structure is designed with the valve seat featuring a V-shaped outer circle. This design is angled to the control rod's contact portion, reducing stress on the control rod and the seat valve's contact surface, thereby maximizing service life. Furthermore, the geometry of the V-shaped outer circle allows the valve seat to be separated from the valve body when removed.

How Does A Top Entry Ball Valve Work?

A top entry ball valve is a specific type of ball valve that provides access to its internal components from the top. This design is particularly advantageous for inline maintenance and repair purposes. When the valve requires repair, it can be easily disassembled. The primary housing contains the ball, while another piece secures the internal components. This configuration facilitates straightforward cleaning, inspection, and repair processes.

The valve's body is crafted from a single-piece material, ensuring sufficient strength and rigidity, even under high operating pressures. Internal components are designed to maintain stable operating pressure, and the inclusion of high-strength connective bolts and an ample margin of wall thickness further simplifies maintenance. Notably, a top entry ball valve differs from a side entry ball valve, particularly in terms of its piping connection.

In a top entry ball valve, the handle is positioned at the top. Manipulating the handle, which is linked to the stem, causes the hollow ball inside the valve to move and adjust the flow. When the hollow end faces forward, the medium starts flowing. Conversely, turning the handle by 90 degrees brings the non-hollow side of the ball into play, stopping the flow of the medium.

While operating similarly to a standard ball valve, the top entry design places the handle or lever on the top, facilitating quick repairs without the need to disassemble the valve from the pipe.

Types of Top Entry Ball Valve

Top entry ball valves are commonly used in various industries for their reliability and ease of maintenance. These valves are designed with the ball and stem assembly from the top, allowing easy access for maintenance and repair without the need to remove the valve from the pipeline. There are different types of top entry ball valves based on their design and application. Here are some common types:

Top entry ball valves are commonly used in various industries for their reliability and ease of maintenance. These valves are designed with the ball and stem assembly from the top, allowing easy access for maintenance and repair without the need to remove the valve from the pipeline. There are different types of top entry ball valves based on their design and application. Here are some common types:

1. Trunnion-Mounted Top Entry Ball Valve:

   • In this design, the ball is supported by trunnions (pivot points) at the top and bottom, which reduces the operating torque and provides stability. It is suitable for high-pressure and high-temperature applications.

2. Floating Top Entry Ball Valve:

   • This type has a floating ball design where the ball is not fixed to the stem. The ball is free to move slightly within the valve body, creating a seal against the downstream seat. It is suitable for low to moderate pressure applications.

3. Full Bore Top Entry Ball Valve:

   • In a full bore or full port top entry ball valve, the ball and bore diameter are the same, resulting in minimal flow restriction. This design is ideal for applications where high flow capacity is crucial.

4. Reduced Bore Top Entry Ball Valve:

   • In contrast to full bore, reduced bore (reduced port) top entry ball valves have a smaller ball and bore diameter, causing some flow restriction. These valves are often used in applications where lower flow rates are acceptable.

5. Metal Seated Top Entry Ball Valve:

   • Metal seated valves use metal-to-metal seating for enhanced durability and resistance to high temperatures and abrasive media. They are suitable for applications where tight shut-off and longevity are critical.

6. Soft Seated Top Entry Ball Valve:

   • Soft seated valves utilize materials like PTFE (polytetrafluoroethylene) for the seating, providing excellent sealing properties. These valves are commonly used in applications where bubble-tight shut-off is required.

7. Cryogenic Top Entry Ball Valve:

   • Designed for low-temperature applications, cryogenic top entry ball valves are equipped to handle extremely cold temperatures, making them suitable for industries such as LNG (liquefied natural gas) and cryogenic gas processing.

8. High-Performance Top Entry Ball Valve:

   • High-performance top entry ball valves are engineered to meet stringent performance requirements, offering features like fire-safe design, anti-static devices, and advanced materials for demanding applications.

When selecting a top entry ball valve, it's crucial to consider factors such as pressure rating, temperature range, flow characteristics, and the specific requirements of the intended application.

What Are The Benefits and Features of Top Entry Ball Valve?

The Top Entry Ball Valve is primarily employed in pipeline and industrial systems, featuring a top entry and line maintenance capability. It offers several advantages, including low fluid resistance, a straightforward design, compact size, lightweight construction, dependable sealing, easy repair and control, and smooth opening and closing operations.

What sets it apart from standard ball valves is its ability to undergo maintenance on the pipeline without the need for disassembly. The seat adopts a back seat configuration, with the back part of the seat holder angled obliquely to prevent impurities from impacting the back seat.

A one-piece body is utilized to ensure ample strength and rigidity, meeting the highest-rated operating pressure for the body. The internal components are specially engineered and selected to ensure stability under various operating conditions. The valve's sufficient margin wall thickness and compatibility with high-strength connecting bolts facilitate maintenance and the ability to withstand pipe pressure.

top entry ball valve vs side entry Ball Valve

These ball valve concepts refer to the manner in which the valve ball and its internal components may be reached, either from the side of the valve or from the top of the valve (top entry).

The top entry design is used when repeated inline maintenance operations are required on the valve. This is due to the fact that the top entry ball valves provide quicker and faster access to the ball and valve trim relative to the side entry valves that need more repair time and space for the same operations.

The two Ball Valve design can be distinguished as follows:

• Top entry ball valves are normally manufactured with cast steel bodies; while side ball entry valves are constructed with (strong) fabricated steel bodies.
• Top entry ball valves include a monolithic design (made of one piece); and side entry valves are made of two or three pieces of assembly.
• Top entry ball valves need more non-destructive testing than side entry ball valve due to their castings; side entry valves are simpler to install and assemble than the top entry, which takes a long time of training and workmanship to function properly
• Top entrance ball valves are usually more costly than side entrance valves and have longer lead times attributed to the casting operations used to produce the body.

FAQs

Are top entry ball valves suitable for high-pressure applications?

Yes, top entry ball valves are designed to handle high-pressure conditions effectively.
Can top entry ball valves be used for corrosive fluids?

Absolutely, the robust construction and choice of materials make them suitable for handling corrosive substances.
What is the typical lifespan of a top entry ball valve?

With proper maintenance, top entry ball valves can have a lifespan of several years, depending on usage.
Do top entry ball valves require specialized installation?

While proper installation is crucial, it follows standard procedures for ball valves.
Are there any environmental benefits to using top entry ball valves?

Yes, ongoing innovations focus on improving energy efficiency and reducing environmental impact, contributing to greener industrial practices.