Patent ID: 7131454
Filing Date: 2006-11-07
Classification: G05D,Y10T

Abstract:
1. A system to inject a secondary fluid into a primary fluid, comprising: a fluid powered motor driven by a primary fluid stream; a liquid additive injection pump driven by the fluid powered motor; said liquid additive injection pump having wherein the liquid additive injection pump includes a piston rod, and the spaced-apart distal and proximal sealing elements are carried thereon; and further wherein the piston rod includes first and second circumferential grooves and first and second retainer rings, said first retainer ring bearing against the distal sealing element during piston downstroke to apply a force that urges the distal sealing element against the cylinder and the second retainer ring bearing against the proximal sealing element during piston upstroke to apply a force that urges the distal sealing element against the cylinder.