Patent ID: 7011158

Claim:
Apparatus connected to the downhole end of a tubing string for cleaning and flushing wells comprising: a hollow tubular member having first and second ends, the first end threaded for connection to the tubing string; at least one primary jet orifice, leading from the tubular member interior at the second end and directed toward the bottom of the well; an open ended shroud covering and protecting the primary jet; and a plurality of secondary jet orifices arranged around the exterior of the tubular member, leading from the tubular member interior and directed upwardly at an acute angle with respect to the longitudinal axis of the tubular member and skewed radially at an angle with respect to a radius of the tubular member surface, wherein the aggregate cross-sectional area of the secondary jet orifices is at least one and one-half times, but not more than four times, the aggregate cross-sectional area of the at least one primary jet orifice.