ANNULAR AND CONCENTRIC FLOW WELLHEAD ISOLATION TOOL AND METHOD OF USE THEREOF

摘要

TITLE: ANNULAR AND CONCENTRIC FLOW WELLHEAD ISOLATION TOOL INVENTOR: RODERICK D. MCLEOD Apparatus for isolating the wellhead equipment from the high pressure fluids pumped down to the producing formation during the procedures of fracturing and acidizing oil and gas wells utilizes a central mandrel concentric inside an outer mandrel and an expandable sealing nipple to seal the outer mandrel against the casing. The sealing nipple is provided with passageways to allow fluids to be pumped down the tubing and/or the annulus between the tubing and the casing in an oil or gas well.