Compression Nut Dimensions Chart: A Comprehensive Guide for Selection and Installation
Compression nuts, also known as compression fittings, are an essential component in various plumbing and hydraulic applications. They provide a secure and reliable connection between pipes and fittings by compressing a ferrule around the pipe. To ensure proper selection and installation of compression nuts, it's crucial to understand their dimensions. This comprehensive chart provides detailed specifications for various sizes of compression nuts, empowering you to make informed decisions and achieve leak-free connections.
Table 1: Compression Nut Dimensions - Metric System
| Nominal Size (mm) |
Thread Pitch (mm) |
Width Across Flats (mm) |
Hex Height (mm) |
Approx. Weight (g) |
| 10 |
1.0 |
17 |
11 |
10 |
| 12 |
1.0 |
19 |
12 |
12 |
| 15 |
1.5 |
22 |
14 |
15 |
| 18 |
1.5 |
24 |
15 |
18 |
| 22 |
1.5 |
27 |
17 |
22 |
| 28 |
2.0 |
30 |
19 |
28 |
| 35 |
2.0 |
34 |
21 |
35 |
| 42 |
2.0 |
38 |
23 |
42 |
Table 2: Compression Nut Dimensions - Imperial System (Inches)
| Nominal Size (in) |
Thread Pitch (in) |
Width Across Flats (in) |
Hex Height (in) |
Approx. Weight (oz) |
| 1/4 |
18 |
11/16 |
9/16 |
0.3 |
| 3/8 |
18 |
13/16 |
11/16 |
0.4 |
| 1/2 |
14 |
15/16 |
13/16 |
0.5 |
| 3/4 |
14 |
1-1/16 |
15/16 |
0.7 |
| 1 |
11-1/2 |
1-5/16 |
1-1/8 |
1.2 |
| 1-1/4 |
11-1/2 |
1-3/4 |
1-3/16 |
1.8 |
| 1-1/2 |
11-1/2 |
2 |
1-1/4 |
2.4 |
Table 3: Compression Nut Dimensions - Flare Fittings
| Size (in) |
Thread Pitch (in) |
Width Across Flats (in) |
Hex Height (in) |
Approx. Weight (oz) |
| 1/4 |
18 |
11/16 |
9/16 |
0.3 |
| 3/8 |
18 |
13/16 |
11/16 |
0.4 |
| 1/2 |
14 |
15/16 |
13/16 |
0.5 |
| 3/4 |
14 |
1-1/16 |
15/16 |
0.7 |
| 1 |
11-1/2 |
1-5/16 |
1-1/8 |
1.2 |
| 1-1/4 |
11-1/2 |
1-3/4 |
1-3/16 |
1.8 |
Effective Strategies for Choosing the Right Compression Nut
To select the appropriate compression nut for your application, consider these key factors:
-
Pipe Size: Ensure the compression nut matches the outer diameter of the pipe you are connecting.
-
Fitting Type: Compression nuts are available for various fitting types, such as compression sleeves, ferrules, and inverted flare fittings. Choose the nut that corresponds to your specific fitting.
-
Material: Compression nuts are typically made of brass, nickel-plated brass, or stainless steel. Opt for a material that is compatible with your application and environment.
-
Thread Size: Verify that the compression nut thread size aligns with the thread size of the fitting and pipe.
Common Mistakes to Avoid
When working with compression nuts, it's essential to avoid the following common mistakes:
-
Overtightening: Avoid excessively tightening the compression nut, as this can damage the fitting or pipe.
-
Using the Wrong Nut: Ensure that the compression nut is specifically designed for the fitting you are using. Using an incorrect nut can lead to leaks or failure.
-
Neglecting Ferrule: Always use a ferrule with a compression nut to create a proper seal.
-
Ignoring Maintenance: Periodically inspect compression nut connections for tightness and corrosion.
Step-by-Step Approach to Installing Compression Nuts
To ensure a secure and leak-free installation, follow these steps:
-
Prepare the Pipe: Cut the pipe squarely and deburr the edges.
-
Insert the Ferrule: Slide the ferrule onto the pipe.
-
Tighten the Compression Nut: Thread the compression nut onto the fitting and hand-tighten it.
-
Use a Wrench: Use a suitable wrench to further tighten the compression nut, ensuring it is snug but not overtightened.
-
Check for Leaks: Pressurize the line and check for leaks. If any leaks occur, retighten the compression nut or replace the components as necessary.
Call to Action
Whether you're a homeowner, plumber, or professional, understanding compression nut dimensions is crucial for successful plumbing and hydraulic projects. By consulting this comprehensive chart and adhering to the guidelines presented, you can select the appropriate compression nuts, avoid common pitfalls, and achieve reliable connections that stand the test of time.
