1. Field of the Invention
The invention relates to a tool saver for use in association with oil or gas wells or the like. More specifically, the invention relates to a tool saver which prevents tools, when withdrawn from a borehole of a well, from falling back into the well in the event of a break in the wire line which lowers and raises the tools.
2. Description of Prior Art
As is known in the art, wire line tools for wells, such as, for example, sand line swabbing equipment, sinker bars, etc., are lowered into and raised out of wells through the well bores of the wells by wire lines. There is a constant danger that, after the tool is raised out of the well, the wire line will break and the tool will fall uncontrollably back into the well. The tool will then have to be retrieved at great cost and inconvenience.
Various devices are known for gripping tools or pipes as they are lowered into wells. Examples of such devices are taught in, for example, U.S. Pat. Nos. 1,422,289, Moody, Jul. 11, 1922, 4,076,337, Childress, Feb. 28, 1978, 4,096,608, Lagerstedt, Jun. 27, 1978 and 4,898,238, Grantom, Feb. 6, 1990.
The '289 patent teaches a device for gripping casings or sections of pipes as they are being raised or lowered into a well. Specifically, the device will hold one section while another section is being coupled or uncoupled.
The drill steel holder of the Childress patent, U.S. Pat. No. 4,076,337, comprises levers 26 and 28 (see FIGS. 3 and 4) having outboard ends connected to a RAM 40. The RAM 40 can draw the outboard ends towards each other or force them apart from each other.
The inboard ends of the levers 26 and 28 comprise rollers 50. When the inboard ends of the levers are drawn towards each other, as shown in FIG. 3, the rollers will embrace a tool, for example a steel drill 68, to prevent the vertical movement of the steel drill.
Jaws 24 and 25 of U.S. Pat. No. 4,096,608, (having inserts 28 and 29) are forced towards each other by a spring 49 to capture a drill pipe 19 as shown in FIG. 2 of the drawings. As seen in FIG. 1, this will prevent the drill pipe 19 from moving in a vertical direction.
In U.S. Pat. No. 4,898,238, Grantom, a stationary jaw 200 acts together with a gripping, or movable, jaw 300 to capture a pipe or the like which is inserted into a well. As seen in FIG. 1, the movable jaw 300 is moved by the action of threaded shaft 320 in threaded block 310.
As is quite clear, none of the references address themselves to the problem as above described.