Elemento de inyección de gas para unidad de craqueo catalítico fluido y sistema de distribución de gas equipado con este elemento de inyección

A gas injection element (10) for a system for distributing a gas inside a chamber of a fluid catalytic cracking unit. This injection member comprises a passage (14) extending entirely therethrough, and-an inner ceramic member (20) having an inner surface (22) that entirely delimits the through-passage (14); and-a hollow metal sleeve (30), inside which at least a portion of the inner member (20) is received, the sleeve (30) and the inner member (20) respectively having an inner surface (32) and an outer surface (24) with matching shapes allowing the inner member (20) to move relative to the sleeve (30) in a direction parallel to an axis (X) of the passage (14), the outer (32) and inner surfaces (24) being provided with fastening elements (26, 36) that engage to reversibly fasten the sleeve and the inner member.