Slip on flanges are rings, that are placed over the pipe end, with the flange face extending from the end of the pipe by enough distance to apply a weld bead on the inside of the diameter. These flanges are called ‘slip on‘ because their inner diameter is larger than that of the connecting pipe which allows it to slip onto the pipe. The slip on flange is connected to the pipe by two welds, one on the backside of the flange and other on the inside of the flange. Slips on flanges are also called ‘hubbed flanges’ because they have a hub with a very low profile.
Slip on flanges must be slid into the pipe before welding, with a double weld, both inside and outside, thus providing better durability and leak proof. The materials used for the manufacture of these flanges are – Carbon steel, Alloy steel, Stainless steel, Titanium, Nickel alloys, etc.
The types of Blind Flanges are
Flat Face –
Flat face flanges are typically used in applications where it is important to have smooth surface contact with the flange.
Raised Face –
The small raised section around the bore is an implementation of the gasket used in this system.
Ring Joint Face –
This face type is used in high-pressure and high-temperature processes, featuring a groove in which a metal gasket sits to maintain the seal.
Tongue and Groove –
These flanges feature matching grooves and raised sections. This aids in installation as the design helps the flanges to self-align and provides a reservoir for gasket adhesive.
Male & Female –
Similar to tongue and groove flanges, these flanges use a matching pair of grooves and raised sections to secure the gasket. However, unlike tongue and groove flanges, these retain the gasket on the female face, providing more accurate placement and increased gasket material options.