A slip-on hub flange (or slip-on neck flange) is a common type of pipe connection component, consisting of a flange disk and a short hub (neck). The hub is connected to the pipe via a fillet weld. Its structure lies between a slip-on plate flange (without a hub) and a weld-neck flange, offering a combination of rigidity and ease of installation.

The flange disk includes a short hub, and the inner diameter of the hub matches the outer diameter of the pipe.

After the pipe is inserted into the flange hub, it is secured with a single or double fillet weld.

It is suitable for use in low-to-medium pressure piping systems (e.g., PN ≤ 2.5MPa) and conditions with minor vibration or temperature fluctuations.