There is disclosed an excavation apparatus (5), such as an underwater excavation apparatus, having means for producing, in use, at least one vortex, spiral or turbulent flow in a laminar flow of fluid, e.g. water. The excavation apparatus (5) comprises a rotor (10) having a rotor rotation axis (A), wherein, in use, flow of fluid passed or across the rotor (10) is at a first angle (a) from the axis of rotation (A). The excavation apparatus (5) comprises the rotor (10) and means or an arrangement for dampening reactive torque on the apparatus (5) caused by rotation of the rotor (10), in use. The turbulent flow is provided within, such as within a (transverse) cross-section, of the laminar flow.

The hydro excavation remote dig system provides for a primary and secondary dig tube attachments that permit a vacuum truck to be used for a remote dig setup. Specifically, the attachments include various attachable handles, corrugated tubing that connects to a reinforcement bar device with releasable clamps to maintain the corrugated tubing in an elongated state during use, a debris box with an integrated safety valve, and a dig tip.

A microtrencher having a vacuum system configured to clean spoil from a microtrench having a side shroud and a suction nozzle. A method of using the microtrencher to cut a microtrench in a roadway and using the vacuum system to clean spoil from the roadway and microtrench.

An excavator bucket has several embodiments adapted for use underwater. A first embodiment includes a front lip and a heel section, with suction ports through the heel section. Another embodiment includes a grated or skeleton bucket with apertures communicating with a suction hopper having suction ports. Yet another embodiment includes a drum grate rotating inside a fitted shroud offset from and conforming to a swept volume of the rotating grate, with the shroud having suction ports, and another embodiment includes a first hopper with rotating arbors forming a crushing screen, communicating with a second suction hopper having one or more suction ports.

A fitting for an excavating apparatus can include a cylindrical pipe that can include a first metal material. In an example, the fitting can be configured for coupling to a hose. The pipe can include an interior surface and an exterior surface. Optionally, a perimeter of the pipe does not exceed a diameter of a first end of the pipe. The fitting can include a cladding layer (e.g., a second metal material) that can be coupled to the first metal material within the interior surface of the pipe. The cladding layer can include an abrasion-resistant material. The cladding layer can be coupled to the pipe such as with a welding operation. The cladding layer can include one or more ridges. The cladding layer can corregate the interior surface of the fitting and exterior surfaces of the fitting which can come into contact with abrasive material.

An elbow fitting for an excavating apparatus can include a curved cylindrical pipe that can include a first metal material. In an example, the fitting can be configured for coupling to a hose. The pipe can include an interior surface and an exterior surface. Optionally, a perimeter of the pipe does not exceed a diameter of a first end of the pipe. The fitting can include a cladding layer (e.g., a second metal material) that can be coupled to the first metal material within the interior surface of the pipe. The cladding layer can include an abrasion-resistant material. The cladding layer can be coupled to the pipe such as with a welding operation. The cladding layer can include one or more ridges. The cladding layer can corregate the interior surface of the fitting and exterior surfaces of the fitting which can come into contact with abrasive material.

A remote debris tank includes a housing having a top and a bottom discharge opening, a pair of discharge doors mounted to opposing lateral sides of the bottom discharge opening and configured for pivotal movement between an open position and a closed position, and an actuating shaft operably coupled to the first and second discharge doors. The remote debris tank also includes a crank lever having a plurality of vertices, where the crank lever is secured to the actuating shaft at a first vertex and configured to rotate with the actuating shaft. A first radial arm has a first end articulately connected to a second vertex of the crank lever and a second end articulately connected to the first discharge door. Similarly, a second radial arm is articulately connected to a third vertex of the crank lever and extending away from the actuating shaft to the second discharge door.

The present application discloses a dredging system for a pre-paved gravel foundation bed surface in open sea deep water, including a dredging mechanism, which includes a dredging suction head, a power component and a dredging pipeline, wherein the dredging suction head is connected with the dredging pipeline; the dredging pipeline is communicated with the power component; the dredging suction head includes at least one ridge surface suction port and at least one furrow suction port; the openings of all the furrow suction ports are lower than those of all the ridge surface suction ports; a lifting mechanism, which is connected with the dredging suction head and is used for lifting the dredging suction head to the gravel foundation bed surface; a moving mechanism, which is connected with the lifting mechanism and is used for driving the dredging suction head to move within a dredging range of the gravel foundation bed surface. By the adoption of the dredging system for the pre-paved gravel foundation bed surface in the open sea deep water of the present application, the dredging suction head includes the ridge surface suction ports and the furrow suction ports, and may suck mud on the top surfaces of gravel ridges and the mud in furrows between two gravel ridges at the same time, thereby guaranteeing the dredging quality of the gravel foundation bed surface and improving the working efficiency. The dredging system is simple in structure, convenient to use and good in dredging effect.

An overflow system for a hopper dredger comprises an overflow tube; an inlet for taking in head water from the hopper; and a collector to collect the flow of head water entering the inlet and guide the flow to the overflow tube. The collector comprises a substantially horizontal top portion which delineates a top of a flowpath for head water into the collector to ensure substantially radial flow into the collector. At least one of the overflow tube and the inlet is adjustable for controlling flow into the overflow system.

The invention relates to a cutter head for removing a mixture comprising water and solid materials from a water bottom, comprising rotating blades each provided with cutting means on a leading edge thereof, said cutter head being rotatably coupled to a tube for transporting said mixture, the shape of the leading edge of said rotating blades being defined by substantially fitting a rounded cone with a rotation axis, wherein each rotating blade at a middle part is coupled to a connecting ring and at a top part is linked to a top part of another rotating blade. The cutter head is characterized in that the rotation axis of said blades is substantially aligned with a rotation axis of said ring; in that a trailing edge of part at least one of said blades is positioned closer to said rotation axis than a leading edge of said blades so as to provide a suction function towards said tube upon rotation of said cutter head; and in that said blades as viewed from said top part at a bottom part of said blades extend to a position beyond said connecting ring. A preferred embodiment comprises a method for using the cutter head according to the invention.