| 摘要 |
<p>In a hydrostatically controlled duplex plunger pump (10) for driving liquids laden with abrasive particles, flowing muds, emulsions or other similar liquids, each plunger piston (14) is coupled to a hydraulic double acting piston-cylinder unit (16a, 16b) of which the intake is controlled by a hydraulic medium so that the travel of its pistons is each time inverted. The extension (b) of the maximum working travel (a+b) of the piston-cylinder units (16a; 16b) is designed to be longer than the working travel (a) of the plunger piston (14) of the respective coupled supply pump (12a; 12b) so that upon a total travel of the maximum working stroke of the piston-cylinder units (16a; 16b) the plunger pistons (14) come out completely of the corresponding cylinder (22). During the normal operation of the pump, the return stroke of the hydraulic piston-cylinder units (16a, 16b) is limited to an extension (a) corresponding to the working stroke (a) of the plunger pistons. Alternatingly, it is possible to control the hydraulic piston-cylinder units (16a; 16b) so that they have a maximum return stroke (a+b), thereby enabling, upon a necessary dismounting, to take the plunger pistons (14) out of their respective cylinder (22).</p> |
