A collection tank for a mobile vacuum excavator includes a front with a closed end, a rear with an open end, a door configured to be closed over the open end, and a linkage assembly having a first end attached to the door and a second end attached to the body. A first pivotal movement drives the first end and second end away from each other, and a second pivotal movement moves the first end and the second end toward each other. An actuator is attached to the first arm and to the second arm so that actuation of the actuator in a first direction drives the first pivotal movement and actuation of the actuator in a second direction drives the second arm the second pivotal movement.

A hydrovac having a chassis, a mud tank and water tank assembly mounted on the chassis, a hydraulic lift assembly capable of raising the mud tank and water tank assembly through a dump angle, the mud tank having a floor, and the floor of the mud tank deepens forwardly. A belt drive is provided for a blower of the hydrovac, along with belt tensioning system.

An apparatus for sealing a vacuum tank door. The apparatus comprises a circular flange attached to a door panel of a vacuum tank, a horizontal crossbar connected to the center of the door panel and a lifting assembly. The lifting assembly comprises an upper linkage arm, a lower linkage arm, and a hydraulic cylinder. Activation of the hydraulic cylinder causes the linkage assembly to move downwards pulling on the horizontal crossbar and pulling the vacuum tank door towards the tank. Activation of the hydraulic cylinder also causes a connection point of the lower linkage arm and the upper linkage arm to move over-center of the connection between the lower linkage arm to the to the tank creating a tight seal between the vacuum tank door and the tank.

The present disclosure describes a vacuum-excavation apparatus that is connectible to a vehicle. The vacuum-excavation apparatus comprises a vacuum tube with an input end; a vacuum assembly for generating a suction force at the input end and drawing a stream of fluidized debris-material into the vacuum tube. The apparatus also includes a boom assembly for supporting the vacuum tube and a tank for receiving the stream of fluidized debris-material from the vacuum tube. The tank provides a boom mount for pivotally connecting the boom assembly and for providing fluid communication between the vacuum tube and the tank. The apparatus also includes an evacuation tube for providing fluid communication between the tank and the vacuum assembly and for distributing at least a portion of stress-loads that are generated by the boom assembly.

A mobile digging and backfill system for removing and collecting material above a buried utility. The system comprises a mobile chassis, a collection tank mounted to the chassis, a water pump mounted to the chassis for delivering a pressurized liquid flow against the material for loosening the material at a location, a vacuum pump connected to the collection tank so that an air stream created by the vacuum pump draws the material and the fluid from the location into the collection tank, and at least one backfill reservoir mounted to the chassis for carrying backfill for placement at the location.

A water pump control system is provided for vacuum excavation equipment. The water pump control system includes a control circuit for controlling a hydraulic actuation circuit configured to control a water pump circuit such that a water pressure produced by the water pump circuit does not exceed a desired water pressure. The hydraulic actuation circuit can include a proportional hydraulic valve, and the control circuit controls a water pump speed by monitoring a water pressure and adjusting an electric current flowing into the proportional valve to meet the desired water pressure. The control circuit can include a pressure transducer mounted to the water pump circuit to monitor the water pressure in real-time.

A material collection container extends in the longitudinal direction of a suction excavator and comprises a container wall which is closed at its two end faces by end walls. A lid is pivotably mounted on a lid shaft so that the material collection container is closed on the upper side and is open in an emptying position. The container has a seal extending between an upper edge and the lid in the closed position so that, in the closed position, the seal seals the container so that negative pressure can be generated in the container. The container wall has a plurality of side segment faces which extend in the longitudinal direction and transition into one another at stiffening edges. The folded upper edge is designed as a hollow profile. The seal is embedded in a groove on the side of the lid directed toward the upper edge.

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.

Mixing systems and methods that include a mixer housing and one or more disk assemblies for mixing and processing materials is disclosed. The disks rotate to mix an additive into the material and to carry agglomerated solids toward a discharge of the mixing system. The disks may have a plurality of fingers or lobes which extend from a central portion of the disks.

A mobile digging and backfill system for removing and collecting material above a buried utility. The system comprises a mobile chassis, a collection tank mounted to the chassis, a water pump mounted to the chassis for delivering a pressurized liquid flow against the material for loosening the material at a location, a vacuum pump connected to the collection tank so that an air stream created by the vacuum pump draws the material and the fluid from the location into the collection tank, and at least one backfill reservoir mounted to the chassis for carrying backfill for placement at the location.