Chemical injection assembly

摘要

A fluid injection assembly of a type designed to inject fluid into a flowing stream of liquid at a predetermined, adjustable rate without the assistance of an outside power source other than the line pressure of the flowing stream itself. The assembly includes a casing having the fluid to be injected disposed therein and at least partially contained by a flexible membrane. Liquid from the flowing stream is partially disposed in fluid communication with the interior of the casing so as to flow in surrounding relation to a portion of the flexible membrane whereby pressure exerted thereon will aid in dispensing of the injection fluid therefrom. An open end of the dispensing line for the injection fluid is disposed within the flowing stream so as to create a negative pressure further aiding in removal of the fluid from within the casing. A liquid flow rate meter is provided so as to give a constant, visual indication of the rate of flow of the liquid into which it is desired to inject a fluid. A similarly constructed fluid injection meter is provided so as to permit visual observation of the rate of fluid injection. A dispensing valve is provided to allow regulation of the rate of injection of fluid into the flowing stream of liquid.