Retrievable straddle packer

A retrievable straddle packer for use in wells, comprising:

• an hydraulic slip assembly;
• a tubular injection mandrel assembly secured to said hydraulic slip assembly and extending downward therefrom, said mandrel assembly having a plurality of injection ports extending through the wall thereof and a plurality of bypass slots extending through the wall thereof below said injection ports;
• upper packer element means disposed on said mandrel assembly adjacent to said hydraulic slip assembly;
• injection spacer means disposed on said mandrel assembly adjacent to and below said upper element means, said injection spacer means including upper and lower packer compression rings separated by a plurality of longitudinal struts defining a plurality of apertures therebetween;
• lower packer element means disposed on said mandrel assembly adjacent to and below said injection spacer means;
• a slip body disposed on and splined to said mandrel assembly below said lower packer element means;
• a plurality of slips disposed on said mandrel assembly, the upper ends of said slips being longitudinally slidably secured to said slip body and the lower ends of said slips being radially slidably secured to a split ring collar assembly therebelow surrounding said mandrel assembly;
• a drag block assembly disposed on said mandrel assembly below said split ring collar assembly and secured thereto;
• J-slot means comprising lug means associated with one of said mandrel assembly and said drag block means, and a cooperating J-slot associated with the other of said mandrel assembly and said drag block means;
• and
• a bypass assembly disposed on said mandrel assembly below said drag block means and secured thereto, said bypass assembly including bypass ports through the wall thereof adapted to communicate with said bypass slots of said mandrel assembly when aligned therewith.