Tank cleaning apparatus

Crude oil tank cleaning apparatus for directing a high velocity stream of fluid from outside the tank into the tank while the tank is in service in order to resuspend or remove sludge from the tank, comprising:

• a gimbal having a substantially straight passageway extending therethrough;
• a mounting bracket for sealingly and rotatably mounting the gimbal in a wall of the tank so that the gimbal has an interior side exposed to the interior of the tank and an exterior side exposed to the exterior of the tank;
• a straight pipe sealingly mounted in the gimbal passageway, the pipe having an inlet end on the exterior of the gimbal for connecting the pipe to a high pressure fluid source and an outlet end on the interior side of the gimbal, the inlet and outlet ends defining a linear flow passageway through the pipe for discharging the fluid in fluid jet into the tank, the flow passageway being straight for at least twenty pipe diameters from the outlet end in order to discharge the fluid in a high velocity, laminar flow stream;
• and
• an actuator, having a first end connected to the exterior side of a rotatable portion of the gimbal and a second end connected to a stationary portion of at least one of the tank or the mounting bracket on the exterior side of the tank, for reciprocating the gimbal and the pipe between selected positions.