IMPROVEMENTS IN AND RELATING TO UNDERWATER EXCAVATION APPARATUS

摘要

There is disclosed an excavation apparatus (105) comprising a controlled flow underwater excavation apparatus. A housing (120) thereof comprises at least one inlet (125) and at least one outlet (130). The at least one inlet (125) is provided on or at a side (126) of the housing (120). A fluid flow path (5) (F) extends from the/each at least one inlet (125) to the outlet (130). The fluid flow path (F) comprises a first portion (F₁) provided at or adjacent the/each at least one inlet (125). The first portion (F₁) is included at a non-300 angle, e.g. is substantially perpendicular, to or converges towards a longitudinal axis (A) of the housing (120) and substantially straight. A second portion (F2) extends or continues from the first portion (F₁). A third portion (F₃) extends or continues from the second portion (F₂). The third portion (F₃) is substantially straight, contains at least part of a rotor (110), and is divergent away from the longitudinal axis (A) of the housing (120) in a flow direction from the inlet (125) to the outlet (130).