Cleaning system for cleaning fluid-conducting tubing

A cleaning system for cleaning tubing used for conducting a fluid therethrough, which system includes balls circulated with the fluid through the tubing from its upstream side to its downstream side, means for separating the balls from the fluid at the downstream side of the tubing, and recirculating means for recirculating the balls back to the upstream side of the tubing;

• said recirculating means comprising a chamber, a first passageway from said chamber to the downstream side of the tubing where the balls are separated from the fluid, and a second passageway leading from said chamber to a point of lower pressure than in said chamber;
• a valve in said second passageway effective when opened to produce, by the difference in pressure between said downstream side of the tubing and said point of lower pressure, a flow of the fluid and balls from said downstream side of the tubing to said chamber;
• and a separator between said chamber and said second passageway to permit the fluid, but not the balls, to flow through said second passageway to said point of lower pressure;
• said separator including a hollow separator tube having perforations through its wall such that the balls accumulate in said chamber on the outer side of said hollow separator tube while the fluid flows through the interior of the hollow separator tube through said second passageway to said point of lower pressure;
• said chamber including a first valve between one side of the chamber and a point at the upstream side of the tubing, and a second valve between its opposite side and another point at the upstream side of said tubing but further upstream than said first-mentioned point, such that when both valves are opened, fluid in the upstream side of said tubing passes through said chamber and washes said balls into the upstream side of the tubing.