There are primarily two main types of elbows, categorized by their radius: long radius (LR) elbows and short radius (SR) elbows. However, elbows are also classified based on the angle of the bend (e.g., 45-degree, 90-degree, 180-degree), and the material they are made from.
Here's a breakdown of the different ways elbows can be classified:
Classification by Radius
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Long Radius (LR) Elbows: The radius of the bend is 1.5 times the pipe's diameter. Long radius elbows are commonly used as they offer lower friction loss due to the gradual change in direction of the fluid.
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Short Radius (SR) Elbows: The radius of the bend is equal to the pipe's diameter. Short radius elbows are used where space is limited, but they create higher friction loss.
Classification by Angle
- 45-degree Elbows: Changes the direction of the fluid by 45 degrees.
- 90-degree Elbows: Changes the direction of the fluid by 90 degrees.
- 180-degree Elbows (Returns): Reverses the direction of the fluid by 180 degrees.
Classification by Material
Elbows are manufactured from a variety of materials, selected based on the application and the fluid being transported. Common materials include:
- Carbon Steel: A common and economical choice for many applications.
- Stainless Steel: Offers excellent corrosion resistance.
- Alloy Steel: Used for high-temperature and high-pressure applications.
- PVC (Polyvinyl Chloride): Used for lower-pressure and temperature applications, often in plumbing.
- CPVC (Chlorinated Polyvinyl Chloride): Similar to PVC but can withstand higher temperatures.
Therefore, while there are countless variations, the core classification is by radius, which leads to the answer of two main types.
