| 摘要 |
<p>The invention relates to a positive displacement pump meant for the installations for continuously dosing the fluid solutions having abrasive particles in suspension, through circuits wherein chemical reactions take place and wherein the dosing flow rate is adjustable and controlled within precise limits. The pump is provided with a bearing ring (3) inserted between the piston (2) and the body (1) of the pump, with a double effect gasket (4), a guiding ring (5), a feeding diffuser (6) and a simple effect gasket (7). The ring and gasket pack is closed by means of a profiled ring (8) and a compensating ring (9) tightened by a threaded sleeve (10) which is screwed in the body (1). The guiding ring (5) and the feeding diffuser (6) are provided with some longitudinal holes (b), with some radial holes (c) and some inner recesses (d) wherein there penetrates the water from a pipe (14), and a valve (15), which form a secondary hydraulic circuit which is connected, via a duct (16) to a buffer tank (17) provided with a float (18) and a valve (19).</p> |
