The Fundamentals of Ball Valves

With the ball valve market projected to reach $16.2 billion in the next five years, it's clear that these components play a critical role across a wide range of industries. From oil and gas to pharmaceuticals and water treatment, many sectors rely on manufacturing companies to deliver high-quality, precision-engineered ball valves for reliable and efficient operation.

In this blog, we’ll explore why ball valves are vital to everyday life and examine how their performance and durability influence key industries and their daily operations.

Defining Ball Valves

To understand the significance of ball valves, it's essential to first examine what they are and how they function.

A ball valve is a shut-off valve that controls the flow of liquids or gases using a spherical ball with a hole through the middle. The valve operates on a simple open-and-close mechanism:

When in the open position, the hole in the ball aligns with the flow path, allowing fluid to pass through.

When closed, the ball is rotated 90 degrees by the handle, blocking the flow completely.

It's important to note that ball valves are not designed for throttling or regulating flow in a partially open position. Using them in a half-open state can lead to uneven pressure distribution and potential damage to internal components.

Ball Valve Applications and Advantages

Ball valves are indispensable components in both commercial and industrial operations, with millions in use worldwide across a broad range of sectors. Wherever fluids or gases flow through pipelines, valves are needed to ensure safe, controlled, and reliable movement—and ball valves are among the most widely used solutions.

These valves are commonly found in industries such as:

Water purification and processing

Energy production

Chemical manufacturing

Oil and gas refineries

Ball valves are particularly critical in gas and water piping systems, which is why they are heavily utilized in the natural gas and chemical industries. Their popularity stems from several key advantages:

Cost-effectiveness

Simple operation

Tight, leak-proof sealing

Ease of maintenance and repair

High safety and reliability, even under extreme pressure and temperature conditions

Thanks to these benefits, ball valves play a vital role in ensuring operational efficiency and safety across a wide range of fluid-handling applications.

Anatomy of a Ball Valve

Understanding the individual components of a ball valve helps highlight its functionality and reliability in various applications. Below is a breakdown of each key part:

The Body

The body is the main structure of the ball valve that houses all internal components. It also connects the valve to the piping system. Ball valve bodies can be manufactured in one-, two-, or three-piece configurations, depending on maintenance needs and system requirements.

The Stem

The stem is the shaft that connects the external handle or actuator to the internal ball. It transmits the quarter-turn rotational force from the handle to the ball, allowing the valve to open or close.

The Ball

At the heart of the valve is the ball—a hollow, perforated sphere that controls the flow of media. When aligned with the flow path, the ball allows flow; when rotated 90 degrees, it blocks it. Precision-engineered balls, such as those manufactured by Hartford Technologies, are critical for achieving leak-free operation.

Packing

The packing is a sealing component that prevents leakage around the stem and stops media from escaping the valve. It plays a crucial role in maintaining the valve’s integrity and environmental safety.

The Bonnet

The bonnet is a protective covering that encloses the stem and packing. It provides additional sealing and mechanical support, serving as a secondary barrier against leaks.

The Seat

The seat is the part of the valve that cradles the ball and forms a seal when the valve is closed. It ensures tight shut-off, preventing backflow or leakage, and contributes to the valve’s durability.

The Handle or Actuator

Located outside the valve body, the handle or actuator is responsible for opening and closing the valve. Manual handles are common in smaller systems, while actuators (electric, pneumatic, or hydraulic) are used in automated or large-scale operations.

Types of Ball Valves

Ball valves are available in a variety of designs and configurations, each tailored to meet specific application needs. The five most common body styles include: one-piece, two-piece (split body), three-piece, top-entry, and fully welded ball valves. Understanding their differences is essential when selecting the right valve for your system.

One-Piece Ball Valves

One-piece valves feature a solid, cast body, which minimizes potential leak points and provides structural integrity. They are cost-effective, compact, and typically non-serviceable, making them ideal for applications where replacement is more practical than repair.

Two-Piece Ball Valves

As the name implies, two-piece valves consist of a main body and a connector, joined together—often with a flange. While they are among the most commonly used ball valves, maintenance typically requires removal from the pipeline, making them less convenient for in-line servicing.

Three-Piece Ball Valves

Three-piece valves include a central body and two end caps, which are usually threaded or welded to the piping system. The center body can be easily removed for cleaning, inspection, or repair without disrupting the connected pipeline. This makes them an excellent choice for processes where regular maintenance is required, allowing operations to continue with minimal downtime.

Top-Entry Ball Valves

These valves allow access to internal components—such as the ball and seats—through the top of the valve body. Ideal for in-line maintenance, top-entry ball valves are often used in high-pressure or critical systems such as High Integrity Pressure Protection Systems (HIPPS), where disassembly of the entire valve would be impractical.

Welded Body Ball Valves

Fully welded ball valves are engineered for underground gas transmission and distribution pipelines. They are designed to eliminate external leak paths, reduce weight, and enhance the mechanical strength of the pipeline. Their seamless, leak-proof construction makes them suitable for long-term, maintenance-free operation.

Choosing the Right Ball Valve

With such a wide range of design options, materials, and configurations, selecting the right ball valve can be complex and time-consuming. Factors such as application type, pressure rating, maintenance requirements, and installation conditions must all be carefully considered to ensure optimal performance and longevity.