Introduction
When pipe nipples are specified by length, measure from one end to the other, including threaded parts, to determine the pipe nipple length. However, the pipe nipple’s overall length does not equal the final space between the two pipe fittings.
Understanding this difference helps the purchaser select the right pipe nipple length for a specific connection and avoid ordering pipe nipples too short or too long.
What Does Pipe Nipple Length Mean?
When pipe nipple length is specified, such as 3 in. or 6 in., the number means the overall length of the pipe nipple from one end to the other, not the middle body section length.
Pipe Nipple Length vs. Thread Length
Overall Length
The overall length of a pipe nipple is the physical length from one end to the other. It includes threaded ends and the unthreaded section.
For standard barrel pipe nipples, end-to-end measurement is mainly used to specify product length.
Thread Length
Thread length is the length of the threaded parts. It is a separate dimension from the overall pipe nipple length and is mainly used to check the thread engagement of threaded and pipe fittings.
Thread length should not be confused with the specified pipe nipple overall length.
Overall Length vs. Installed Connection Distance
Overall length refers to the physical size from one end to the other before installation of pipe nipples. The installed space between two pipe fittings will be shorter because both threaded ends fit into a female thread.
Consequently, you cannot easily select pipe nipples by measuring the visible space between two pipe fittings. When selecting pipe nipples, you also need to consider the required thread engagement at both ends.
How Is a Standard Barrel Nipple Length Measured?
Step 1: Measuring overall length
Measure the pipe nipple from one end to the other, including the threaded parts. This is the overall length.
Step 2: Measure Thread Length individually
If you need to verify thread engagement, measure the threaded part individually.
Step 3: Confirm specifications
Confirm the pipe size, overall length, thread types, and materials together when ordering.
How to Measure a Close Nipple Length?
Close nipples are also measured from end to end. Unlike standard barrel pipe nipples, close pipe nipples have threading covering nearly the entire pipe nipple length, leaving little or no unthreaded middle section.
So, the overall end-to-end length is still the key size, but you also need to confirm the application, the thread standard, and thread engagement.
Pipe Nipple Length Chart
Pipe nipples are available in various standard lengths, and we can provide custom lengths for drawings or purchasing specifications.
Download the Pipe Nipple Size & Dimension chart
How to Choose the Right Pipe Nipple Length?
Choosing the correct pipe nipple length depends on several factors.
Installation Space
Available installation space determines how long pipe nipples can be used. In compact spaces, you need more short pipe nipples.
Connection Distance
Longer pipe nipples may be required when components are separated by a larger distance.
Barrel nipples provide more flexibility because they are available in many lengths.
Thread Engagement Requirements
The selected nipple length must provide enough thread engagement with connected fittings.
Incorrect thread engagement may cause:
- Leakage
- Loose connections
- Reduced system reliability
Pipe Nipple Length Standards
ASTM A733 specifies requirements for steel pipe nipples, including standard and specific lengths and threaded end requirements.
ASME B1.20.1 covers threaded pipe nipples, such as NPT, and is relevant when confirming thread specifications.
Customer-specific drawings and specifications
For non-standard lengths or specific configurations, we will confirm customer drawings and purchaser specifications before manufacturing.
Common Mistakes When Measuring Pipe Nipples
Measuring Only the Unthreaded Section
Some buyers measure only the center pipe section and ignore the threaded ends.
This can result in ordering an incorrect length.
Confusing Pipe Size With Nipple Length
Pipe size refers to nominal diameter.
Pipe nipple length refers to the physical distance from end to end.
These are two different specifications.
Ignoring Thread Standard
A correct length with the wrong thread type may still fail during installation.
Always confirm:
- NPT
- BSP
- BSPT
before ordering.
Custom Pipe Nipple Length Manufacturing
Many industrial applications require custom pipe nipple dimensions.
Professional manufacturers can provide:
- Custom lengths
- Custom thread types
- Custom materials
- Special requirements
Common customized options include:
- Stainless steel pipe nipples
- Carbon steel pipe nipples
- Galvanized pipe nipples
- Brass pipe nipples
Frequently Asked Questions
How do you measure a pipe nipple length?
Pipe nipple length is usually measured from one end to the other, including threaded sections. This measurement is called the overall length.
Does pipe nipple length include threads?
Yes. In most cases, overall pipe nipple length includes both threaded sections and the center pipe section.
Can pipe nipples be made in custom lengths?
Yes. Manufacturers can produce custom pipe nipples according to customer drawings, specifications, and application requirements.
Conclusion
The key to selecting pipe nipples of the specified length is the overall end-to-end length, including the threads.
When confirming the needed length, consider the required finished connection distance and thread engagement at both ends. Confirm the pipeline size, threaded standard, and materials before ordering.
If the standard length does not match the required connection sizes, we will accept your applications or drawings and specify a custom pipe nipple length.