摘要 |
A new throat bushing for use with rotary fluid equipment (10) having a seal cavity (28) defined by a shaft (14), a shaft housing (13), and a seal (26) engaging the shaft, which includes an annular shaped element (50, 62, 66, 90, 92, 108, 120) for securement to the housing (13) at the entrance to the cavity. The shaft can pass through the element and rotate freely, without contact. A spiral groove (64, 88, 98, 122), or multiple spiral grooves, may be cut into the radial surface (60) facing towards the seal. The groove is configured to guide any abrasives radially inwardly, away from the cavity bore, toward the shaft. Through this mechanism, any contaminants are easily removed from the seal cavity by the use of a minimum flow of clean flush injected into the seal cavity. |