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This article primarily introduces the specific length, orifice diameter, and dimensions of ball valves. Of course, different production standards result in different dimensions. Choosing the wrong size can damage the piping system.
Ball valve dimensions include: nominal size, orifice diameter, length, and valve body dimensions. Different ball valves have different size standards. Ball valves include floating ball valves and trunnion ball valves, and their connection methods include flange connections, threaded connections, and welded connections.
Understanding ball valve size specifications is essential for selection. Both distributors and contractors need to provide complete production standards and dimensions when purchasing.
What Do Ball Valve Dimensions Include?
Ball valve dimensions usually refer to the product dimensions under different production standards.
The following table shows the various size specifications of ball valves:
| Dimension | Meaning |
|---|---|
| Nominal size | Pipeline designation, such as DN50 or NPS 2 |
| Bore diameter | Internal flow opening through the ball |
| Face-to-face length | Distance between flange faces |
| End-to-end length | Overall length between welded or threaded ends |
| Overall height | Distance from valve centerline to the highest point |
| Body width | Maximum width of the valve body |
| Stem dimensions | Stem diameter, height, and connection profile |
| Mounting dimensions | Interface for gearbox, pneumatic actuator, or electric actuator |
Not only must the ball valve connections be of the same standard, but even two DN50 ball valves require consideration of length and orifice diameter during installation.
How Do You Determine the Size of a Ball Valve?
To determine the size of a ball valve, it’s not only necessary to match the pipe size, but also to determine whether its manufacturing standard is DN or NPS. It’s also necessary to determine whether it’s a full-bore or reduced-bore valve.
The following items need to be determined:
- Position rating of the ball valve
- Operating temperature range
- Connection method
- Correspondence with pipe size
- Material
- Handle type: manual, pneumatic, electric, or gearbox operated
- Other size specifications
- These are all things to consider when purchasing ball valves.
What Size Are Floating Ball Valves?
Floating ball valves are mostly used in small to medium-sized piping systems. They have a perforated ball inside.
This type of ball valve is often used in compact structures. Connection methods are mostly threaded, flanged, and welded. Common materials include carbon steel and stainless steel.
The actual size of a floating ball valve is related to: pressure rating, seat load, operating torque, valve body design, and manufacturer capabilities. Higher pressure valves exert greater pressure on the float, thus increasing the operating torque.
For the most accurate and specific size chart, please refer to the supplier’s floating ball valve catalog (PDF).
What Size Are Trunnion-Mounted Ball Valves?
A trunnion-mounted ball valve is a ball valve mounted on a trunnion, supported by fixed upper and lower shafts or bearings. It is also called a trunnion ball valve.
This type of ball valve is often used in large industrial piping systems, where it can withstand higher pressures and temperatures. Common connection methods are flange connections or welding.
Compared to floating valves, trunnion valves have the following characteristics:
- Larger and heavier valve body
- More robust stem and bearing systems
- Different face dimensions
- Higher requirements for actuators
- Requires additional drainage, venting, or sealing connections
How Do Floating and Trunnion Ball Valve Dimensions Differ?
| Factor | Floating Ball Valve | Trunnion-Mounted Ball Valve |
|---|---|---|
| Typical application | Small to medium industrial lines | Medium to large or higher-pressure pipelines |
| Body profile | Generally more compact | Generally larger and heavier |
| Ball support | Seats support the ball | Ball supported by trunnions |
| Common connections | Threaded, socket weld, flanged, butt weld | Flanged and butt weld |
| Actuator requirement | Lower in many small sizes | Requires project-specific torque review |
| Dimensional verification | Manufacturer catalogue and drawing | Detailed GA drawing usually required |
How Do Flanged Ball Valve Dimensions Work?
The connection dimensions for flanged ball valves include: flange outer diameter, bolt circle diameter, number of bolt holes, bolt hole diameter, flange thickness, and sealing surface type. This is a flange connection.
How Do Threaded Ball Valve Dimensions Differ?
The connection of a threaded ball valve needs to be determined: NPT, BSPT, BSPP, or another threaded system. This type of ball valve is mostly used in compact systems and small-diameter piping systems.
Ball valves also come in one-piece, two-piece, and three-piece types. Different styles have different specific dimensions, and the end-to-end dimensions also differ.
Therefore, when selecting a threaded ball valve, it is essential to have more precise and detailed requirements regarding its dimensions.
How Do Socket-Weld Ball Valve Dimensions Work?
Socket-welded ball valves have a recessed socket, which is inserted into the pipe and then welded.
Specific data includes: socket bore, socket depth, end wall thickness, and overall valve length. These together constitute the socket-welded ball valve.
This type of ball valve is mostly used in small-diameter systems, but it can also be used in some small-diameter, high-pressure systems. During installation, appropriate welding procedures should be followed to limit heat transfer to PTFE, RPTFE, PPL, or other internal seat materials.
How to Do Butt-Weld Ball Valve Dimensions Work?
This involves welding directly onto the pipe. Dimensions to consider during welding include: end-to-end length, weld end outer diameter, wall thickness, internal transition, and bevel geometry.
The manufacturing standard is ASME B16.25, which specifies the corresponding dimensional requirements for this type of ball valve.
Why Can Two Ball Valves of the Same Size Have Different Dimensions?
The following factors can affect their dimensions:
- Construction: Floating or Trunnion
- Type: Full-bore or Reduced-bore
- One-piece, Two-piece, Three-piece, Split, or Fully Welded Body
- Pressure Requirements
- Welding Method
- Soft Seat Design Requirements
- Start-up Configuration
- Design Requirements
Ball Valve Dimensions Chart: Reference Example
The following is a ball valve dimension chart:
| Nominal Size | Typical Design | Connection | Pressure Rating | Length | Height |
|---|---|---|---|---|---|
| DN15 / NPS 1/2 | Floating, full port | Threaded | Project-specific | Reference only | Reference only |
| DN25 / NPS 1 | Floating, full port | Socket weld | Project-specific | Reference only | Reference only |
| DN50 / NPS 2 | Floating, full port | Flanged | Class 150 | Reference only | Reference only |
| DN100 / NPS 4 | Floating or trunnion | Flanged | Class 150/300 | Reference only | Reference only |
| DN200 / NPS 8 | Trunnion, full/reduced port | Flanged or butt weld | Project-specific | Reference only | Reference only |
Which Standards Affect Ball Valve Dimensions?
The dimensions of ball valves are related to manufacturing standards. The following are ball valve standards:
- ASME B16.10: Face-to-Face and End-to-End Valve Dimensions
- ASME B16.5: Flange Dimensions and Pressure and Temperature Ratings
- ASME B16.25: Butt Weld Preparation
- API 6D: Requirements for Pipeline Valves
- API 608: Requirements for Metal Ball Valves
- EN 558: Specification of Face-to-Face Dimensions for European Valve Systems
What Should Buyers Check Before Approving a Ball Valve Drawing?
| Drawing Item | Why It Matters |
|---|---|
| DN/NPS and bore | Confirms pipeline and flow-area compatibility |
| Face-to-face length | Prevents installation mismatch |
| Flange drilling | Ensures correct bolt alignment |
| Pressure class | Confirms pressure-system compatibility |
| Overall height | Verifies handle or actuator clearance |
| Mounting pad | Supports actuator installation |
| Weld-end detail | Confirms pipe schedule and bevel |
| Material specification | Confirms corrosion and pressure suitability |
| Valve weight | Supports lifting and pipe-support planning |
The table above lists the points to consider when purchasing ball valves.
Summary
The above content outlines the dimensional requirements for ball valves. Factors such as design, orifice diameter, pressure rating, valve body structure, and end connections are all related to dimensions. A thorough understanding of ball valve specifications is essential for both purchasing and manufacturing.
