| 摘要 |
<p>The downhole pump comprises a two-piece cylinder (1) composed of a hydroprotection cylinder (2) having a sealing device (5) and a cylinder (3) having a suction valve (25). A plunger (4) is equipped at the bottom with a centering shoe (31), an injection valve (26) and a cage (28). A gap (33) is formed between the lateral surface of the plunger (4) and the inner surface of the working cylinder (3) beneath a bottom seal (7) and the cavity of the working cylinder (3), said gap communicating with the external environment. The sealing device (5) contains a top seal and a bottom seal (6, 7) which are spaced apart and in which, in cylindrical bushings (8), external and internal seal cascades (10, 11), wiper seals (12, 13) and top and bottom seals (16, 17) are positioned. A closed cavity (18) with lubricating liquid is formed between the seals (6, 7), in which cavity slide bearings (22, 23) are arranged. The plunger (4) is equipped with a shank (35), positioned in an internal cavity of a crossover (42) and is equipped with locks, having longitudinal and transverse slots (45, 46) for the positioning therein of shank (35) pins for securing the plunger (4).</p> |
