Strainers for boiling water reactors.

摘要

A debris catching arrangement is disclosed for incorporation within the flow plenum up stream or below the rod supporting grid of the lower tie plate assembly. The device is preferably placed within the lower tie plate flow plenum between the fuel bundle inlet orifice and the rod supporting grid structure supporting the fuel rods; alternate placement can include any inlet channel upstream of the fuel rods including the fuel support casting. The disclosed debris catching designs include successive side-by-side coil springs placed in layers across the tie plate plenum. Preferably, the respective tie plates are placed in alternating directions with a first layer of springs oriented at 90 DEG to an alternate and underlying layer of springs. Multiple layers of such springs are used with four layers being preferred. At their respective crossing points, the springs of adjacent layers are joined-as by welding-with the result that the filter is a solid unitary mass.