Paper: Bull Dog Bailer

The Bull Dog@ Bailer (Patent No. 4,493,383) offers a method to clean out sand and debris from the wellbore or casing without loading the hole and circulating. The bailer tool assembly consists of a bottom hole tool, float valve, cavity as per weight chart, and the Bull Dog@ Bailer. The tool must be run in fluid, so cavity length cannot exceed the column. Reciprocation (5 ft. stroke) of the pump assembly draws fluid and sand in through the bottom hole tool, through the float valve, and up into the cavity tubing chamber. Sand and debris collect in the tubing chamber above the float valve while the fluid goes through the pump assembly and is discharged to the annulus. The pump rod is hexagonal to permit normal rotation of the entire tubing string. The size and weight of the tubing used between the float valve and the pump assembly to form the chamber may be varied to apply to existing hole conditions and desired operations. All principal parts of the tool are manufactured from high-strength, heat-treated alloy steel.