Abstract: An apparatus for protecting blowout preventers during well fracturing and/or stimulation treatments is disclosed. The apparatus includes a hollow spool with spaced-apart inner and outer sidewalls that define an annular cavity. A mandrel is forcibly reciprocatable in the cavity. The mandrel includes an annular seal at a bottom end for sealingly engaging a bit guide attached to a top end of the casing. The apparatus is mounted above a BOP attached to a casing spool of the well before well stimulation procedures are begun. The mandrel is stroked down through the BOP to protect it from exposure to fluid pressure as well as abrasive and/or corrosive well stimulation fluids, especially extreme pressures and abrasive proppants. The advantage is a simple, easy to operate apparatus for protecting BOPs which provides full access to the well casing with well servicing tools to facilitate well stimulation at pressures approaching the burst pressure rating of the well casing.

Abstract: An apparatus for protecting blowout preventers during well fracturing and/or stimulation procedures is disclosed. The apparatus includes a hollow spool with spaced-apart inner and outer sidewalls that define an annular cavity. A mandrel is forcibly reciprocatable in the cavity. The apparatus is mounted above a BOP attached to a casing of the well before well stimulation procedures are begun. The mandrel is stroked down through the BOP to protect it from direct contact with the well stimulation fluids, especially abrasive proppants. The advantage is a simple, easy to operate apparatus for protecting BOPs which provides full access to the well casing with well servicing tools to facilitate well stimulation at moderate pressures.

Abstract: An apparatus and method for completing or recompleting wells for production is disclosed. The apparatus and method are particularly adapted to the completion of oil or gas wells having a plurality of production zones. In particular, the apparatus is useful for oil or gas wells having production zones which require stimulation prior to initial production of the well, or producing wells which require recompletion in order to open new zones or to reperforate and stimulate existing zones from which production has slowed down or ceased. The apparatus comprises a header spool having a pressure rating that is about as high as the burst pressure rating of the surface casing of the well. The header spool is mounted to a casing spool before a wellhead is placed on the well. The header spool has an internal passage which is at least as large as the diameter of the casing in the well. This permits an efficient completion of the well after the casing is cemented in.

Abstract: An apparatus and method for completing or recompleting wells for production is disclosed. The apparatus and method are particularly adapted to the completion of oil or gas wells having a plurality of production zones. In particular, the apparatus is useful for oil or gas wells having production zones which require stimulation prior to initial production of the well, or producing wells which require recompletion in order to open new zones or to reperforate and stimulate existing zones from which production has slowed down or ceased. The apparatus comprises a header spool having a pressure rating that is about as high as the burst pressure rating of the surface casing of the well. The header spool is mounted to a casing spool before a wellhead is placed on the well. The header spool has an internal passage which is at least as large as the diameter of the casing in the well. This permits an efficient completion of the well after the casing is cemented in.

Abstract: A wellhead isolation tool is disclosed that is unique because the tool has no direct connection between the high pressure valve and the mandrel. Well stimulation fluids are pumped through one or more high pressure bores which communicate with a mandrel injection head that directs the fluids into the mandrel. The injection head and the mandrel are enclosed in a sealed bore and reciprocatably movable with a piston which is used to stroke the mandrel into and out of a wellhead and to lock the mandrel in an operating position wherein ports in the injection head are aligned with the high pressure bores. The tool provides superior safety features and ease of operation.

Abstract: A well tree isolation apparatus comprising a single hydraulic cylinder supported in axial alignment over a well tree by at least two elongated support rods. The hydraulic cylinder support rods are connected between a base plate and a hydraulic cylinder mounting plate to support the hydraulic cylinder above the well tree a distance approximately equal to the height of the production tree. The apparatus permits the insertion of a single length of high pressure tubing through any well tree, regardless of its height. Once the high pressure tubing is seated in a well tubing or casing, the hydraulic cylinder, hydraulic cylinder plate and support rods are removed to provide 360.degree. access to a high pressure valve attached to the top of the high pressure tubing.