Category: 

What are Compression Fittings?

Article Details
  • Written By: Lori Kilchermann
  • Edited By: Jacob Harkins
  • Last Modified Date: 01 December 2016
  • Copyright Protected:
    2003-2016
    Conjecture Corporation
  • Print this Article
Free Widgets for your Site/Blog
Helium is the only element that was discovered in space before it was found on Earth.  more...

December 10 ,  1948 :  The UN adopted the Universal Declaration on Human Rights.  more...

Compression fittings use a nut slid over a length of tubing followed by a ferrule or an O-ring. This nut is tightened against another line or fitting, which in turn compresses the ferrule or O-ring, thereby creating a seal. The compression fittings are most commonly found in plumbing applications where a fast, easy seal is required. The fittings are typically a single-use product, but many types of compression fittings can be re-used by replacing the ferrule or O-ring and re-tightening the nut.

Found under many household and commercial properties' sinks, compression fittings provide watertight seals in drains as well as water lines and fixtures or faucet fittings. The fittings rarely require more than hand tightening to achieve a seal and can even be used when mixing plumbing types such as stainless steel with copper or plastic. Compression fittings rarely require pipe sealant or Teflon thread tape to achieve a watertight seal. In rare occasions, a fitting will require a slight turn with a wrench to complete the seal.

Ad

Often used in tight spaces that would make soldering a fire hazard, compression fittings are easily installed. These fittings are also used in high-risk applications such as gas and oil lines where application of flame or heat would be too dangerous. The most common cause for a compression fitting to fail is from over-tightening it at the time of installation. By over-tightening, the ferrule becomes out of round and fails to give a complete seal. When the fitting is sealed a leak test is performed. If any leak occurs at the fitting, the nut is slowly tightened until the leak disappears.

While extremely useful in sealing plumbing lines, compression fittings are not as strong or as visually impressive as soldered and sweated connections. In applications which are prone to over tightening or rigorous use such as an outdoor water faucet, a soldered connection may be a better option than compression fittings. Also, in areas and applications that are prone to water line chattering and shaking, the soldered connection may prove to be more durable.

In applications that mandate occasional removal or disassembly for maintenance or meter changing, compression fittings are preferred for the ease of re-assembly. Requiring little or no tools to complete the assembly, the compression fitting is easy to install in cases of emergency and are often installed as a temporary fix to a problem that will eventually be solved with the application of a soldered connection.

Ad

You might also Like

Recommended

Discuss this Article

anon278055
Post 1

Now it's very clear to me about compression fittings!

This kind of equipment is delicate, especially for people who are not familiar with it. There is a need to be careful in handling it.

Post your comments

Post Anonymously

Login

username
password
forgot password?

Register

username
password
confirm
email