How to Install a Slip-on Flange

Flanges are most often used to connect pipes that have diameters of more than 2 inches. The flange's joint consists of two matching disks of metal, separated by a gasket, that are bolted together to achieve a secure seal with the gasket material. The flange is attached to the pipe by screwed fittings. The flange uses force provided by the bolts to pre-load the gasket. When internal pressure is applied, there is enough contact stress between the flanges and gasket to maintain a seal.

The most common types of flanges are found and used in toilet piping.
  1. Check the flange and pipe to make sure there is no damage that may prevent a proper seal from being formed.

  2. Slide the slip-on flange onto the pipe using your hand. Determine where you will be welding the flange to the pipe. In most cases, you will be welding the flange to the end of the pipe.

  3. Use a welder to weld the inside and outside of the flange to the pipe. This will create a strong seal between the pipe and flange.

  4. Perform a pressure test to ensure the welded seal does not leak. Turn on the water leading to the pipe and observe the pipe for any leaks.

About the Author

David Shaw has been writing professionally since 2006. He has featured music-related articles in "Connections" and "Axis Magazine." Shaw attended Florida State University where he majored in communications and he was granted a certificate of completion from Full Sail Real World Education for the recording arts program.