What is the name of the supporting steel bar at the bottom of the carpenter's hanging mould?

Positioning rib. The new hanging formwork support is also called high-low span formwork support and new building hanging formwork positioning support and hanging formwork positioning rib. Hanging formwork means that the formwork is hung on other unsupported fixtures, also called hanging formwork, which is used to turn up the parts with height difference such as beams, and the most obvious place with other formwork construction is that the lower mouth is unsupported.