Abstract: There is provided a tie knot member for an elongated strip of fabric. The tie knot member includes a shell having a truncated, conical shape with a cardioid-like cross-section. The shell has a base end with a lower aperture. The shell has a top end with an upper aperture. The shell has a rear portion extending between the base end and the top end. The rear portion includes a cusp and a pivotable connector connecting the shell across the cusp. The pivotal connector is so positioned to retain the shape of the shell, whereby when the elongated strip of fabric is passed through the shell and the shell is spread at the top end, the upper aperture is enlarged and the lower aperture is reduced, thereby cinching the lower aperture against the elongated strip of fabric.

Abstract: There is provided a tie knot member for an elongated strip of fabric. The tie knot member includes a shell having a truncated, conical shape with a cardioid-like cross-section. The shell has a base end with a lower aperture. The shell has a top end with an upper aperture. The shell has a rear portion extending between the base end and the top end. The rear portion includes a cusp and a pivotable connector connecting the shell across the cusp. The pivotal connector is so positioned to retain the shape of the shell, whereby when the elongated strip of fabric is passed through the shell and the shell is spread at the top end, the upper aperture is enlarged and the lower aperture is reduced, thereby cinching the lower aperture against the elongated strip of fabric.

Abstract: An hydraulic snubbing unit has a pair of hydraulic cylinders for moving travelling snubbing slips towards and away from stationary snubbing slips to snub a pipe through the snubbing unit, the hydraulic cylinders having spaced, parallel cylinder rods. A pipe guidance apparatus has pipe guides between the stationary snubbing slips and the travelling snubbing slips, the pipe guides each having a pair of cylinder rod openings spaced apart from one another and slidably receiving the rods of the hydraulic cylinders and a pipe guidance opening located between the cylinder rod openings and slidably guiding the pipe, and a pipe guide spacer having extendable and contractible interconnections between the pipe guides.

Abstract: A method of and apparatus for inserting tubing into a well bore by supplying a leading end of a well bore tubing towards the well bore, with a piston on the leading end of the well bore tubing; and supplying fluid under pressure to the piston to force the piston and the leading end of the well bore tubing downwardly into the well bore.

Abstract: A pressure relief system for use in live well snubbing has blow-out preventers (BOPs) mounted one above the other in a BOP stack on a live well bore and spools installed between successive ones of the blow-out preventers, the spools and the blow-out preventers being arranged along a passage communicating with the well bore and serving to receive piping therethrough during snubbing operations. Supply ducts communicating with the passage between successive ones of the blow-out preventers are provided with gas pressure regulators.

Abstract: A snubbing configuration for inserting a pipe and/or a tool assembly on a pipe into a live well head employs a telescopic cylinder, e.g. a telescopic snubbing jack, between an upper BOP, e.g. an annular BOP, and a lower BOP, e.g. a double-gate BOP, in place of a conventional stripping BOP and an extended spool which are required in conventional configurations to accommodate long tool assemblies.

Abstract: A method of inserting tubing into a live well bore, includes attaching a resilient piston to a lower end of the tubing, lowering the piston into a passage at a well head to locate the piston in a position above a closure which prevents the escape of fluid from the well bore through the passage, sealing the passage around the tubing above the piston and opening a path of communication between the well bore below the closure and a portion of the passage above the piston to equalize the hydraulic pressure above the piston with that below the closure. The closure is then opened and fluid is pumped from a fluid reservoir into the passage above the piston to force the piston and the tubing downwardly in the well bore. Subsequently, the piston and the tubing are allowed to descend under gravity while fluid flows upwardly in the well bore past the piston by deformation of the piston by the pressure of the fluid.