Unlock the mystery: how to determine flare fitting size without a headache

Flare fittings are essential components in fluid systems, providing secure and leak-free connections. Determining the correct flare fitting size is crucial to ensure proper system operation and prevent potential failures. This comprehensive guide will provide a step-by-step approach to accurately determining the flare fitting size for your specific application.

Understanding Flare Fitting Types

Before determining the size, it’s essential to understand the different types of flare fittings. The two most common types are:

• SAE (Society of Automotive Engineers) Flare Fittings: Used in automotive, aerospace, and industrial applications. They feature a 45-degree flare angle and are available in various sizes.
• JIC (Joint Industry Council) Flare Fittings: Typically used in hydraulic systems. They have a 37-degree flare angle and are also available in a range of sizes.

Measuring Flare Tube Outer Diameter (OD)

The first step in determining the flare fitting size is to measure the outer diameter (OD) of the flare tube. Use a caliper or micrometer to accurately measure the OD at the end of the tube where the flare will be created.

Determining Flare Fitting Body Size

The flare fitting body size corresponds to the tube OD. Common flare fitting body sizes include:

• 1/4″ for tube ODs of 0.250″
• 3/8″ for tube ODs of 0.375″
• 1/2″ for tube ODs of 0.500″
• 3/4″ for tube ODs of 0.750″
• 1″ for tube ODs of 1.000″

Selecting Flare Fitting Thread Size

The flare fitting thread size determines the thread type and pitch used to connect the fitting to the mating component. Common thread sizes include:

• 1/4 NPT (National Pipe Thread)
• 3/8 NPT
• 1/2 NPT
• 3/4 NPT
• 1 NPT

Identifying Flare Fitting Thread Length

The flare fitting thread length refers to the length of the threaded portion of the fitting. Common thread lengths include:

• 1/4″ for smaller flare fitting sizes
• 3/8″ for medium flare fitting sizes
• 1/2″ for larger flare fitting sizes

Determining Flare Fitting Configuration

Flare fittings can have different configurations, such as:

• Straight: The fitting extends straight out from the tube.
• Elbow: The fitting creates a 90-degree bend in the tube.
• Tee: The fitting connects three tubes at a T-junction.
• Cross: The fitting connects four tubes at a cross-junction.

Matching Flare Fitting to Tube and Application

Once you have determined the flare fitting size, thread size, thread length, and configuration, you can select the appropriate fitting for your specific application. Consider the following factors:

• Tube material and thickness
• Operating pressure and temperature
• Fluid compatibility
• Space constraints

Final Note: Ensuring Precise Flare Fitting Connections

Accurately determining the flare fitting size is essential for achieving leak-free, reliable fluid system connections. By following the steps outlined in this guide, you can ensure that your flare fittings are the correct size and configuration for your application. Remember to consider all relevant factors and refer to manufacturer specifications for precise measurements and compatibility information.

Answers to Your Most Common Questions

1. What is the difference between SAE and JIC flare fittings?

SAE flare fittings have a 45-degree flare angle, while JIC flare fittings have a 37-degree flare angle.

2. How do I measure the flare fitting body size?

Measure the outer diameter (OD) of the flare tube and match it to the corresponding flare fitting body size.

3. What is the most common flare fitting thread size?

1/4 NPT is the most common flare fitting thread size.

4. How do I determine the flare fitting thread length?

Consider the thickness of the mating component and the space constraints to select the appropriate flare fitting thread length.

5. What are the different flare fitting configurations?

Flare fittings can be straight, elbow, tee, or cross configurations.