The invention relates to a burner ring for turbofan jet engines. The ring includes an upstream annular envelope which forms a channel which is open axially in the downstream direction, and a manifold for injecting fuel into the channel. The ring includes multiple sectors connected together. Each sector has a fuel inlet which is connected to the fuel injection manifold. Part of the upstream annular envelope is in the core flow. Each sector has a connector which receives the fuel inlet and a ventilation duct which extends through the channel and upstream of the injection manifold. Each sector is fitted with an inlet for a bypass air, which air is then emitted by the ventilation duct to cool the injection manifold. A sector of downstream annular envelope is arranged downstream of the injection manifold to protect this manifold.