BACKGROUND OF THE INVENTION

I. Field of the Invention

The present disclosure relates generally to tools for rig drilling equipment in the field of oil and gas wells, and more specifically to an apparatus for safely transporting oilfield tubulars, and more particularly to an apparatus to raise and/or lower a length of oilfield tubulars and/or for otherwise safely moving a length of oilfield tubulars.

II. Description of the Prior Art

Conventional drilling operations for hydrocarbon exploration, exploitation and production utilize many lengths of individual tubulars which are made up into a string, where the tubulars are connected to one another by means of screw threaded couplings provided at each end. Various operations require strings of different tubulars, such as drill pipe, casing and production tubing.

The individual tubular sections are made up into the required string which is inserted into the ground by a make up/break out unit, where the next tubular to be included in the string is lifted into place just above the make up/break out unit. A first conventional method of doing this uses a single joint elevator system which attaches or clamps onto the outside surface of one tubular section and which then lifts upwards. A second conventional method for doing this utilizes a lift nubbin which comprises a screw thread which engages with the box end of the tubular such as a drill pipe, and the lift nubbin and tubular are lifted upwards by a cable. However, this second method in particular can be relatively dangerous since the lift nubbin and tubular will tend to sway uncontrollably as they are being pulled upwards by the cable.

Once lifted into place, conventional drilling rigs utilize a make up/break out system to couple/decouple the tubular pipe sections from the tubular string. A conventional make up/break out system comprises a lower set of tongs, which are brought together to grip the lower pipe like a vice, and an upper set of tongs which firstly grip and then secondly rotate the upper pipe relative to the lower pipe and hence screw the two pipes together. In addition to this conventional make up/break out system, a conventional drilling rig utilizes a rotary unit to provide rotation to the drill string to facilitate drilling of the borehole, where the conventional rotary unit is either a rotary table provided on the drill rig floor or a top drive unit which is located within the drilling rig derrick.

In order to position a tubular and hoist it into place, elevators are generally employed (using a threaded collar as a contact point for the lift), enabling the tubular to be lifted into place, connected to a string of tubulars, and run into a wellbore. Again, one type of elevator is a slip type elevator, sometimes referred to as a “MYC/HYC” elevator. The slip-type elevator includes slips, which may have teeth or be non-marking, that engage the outer diameter of the tubular. Typically, the slips are pushed radially inward into engagement with the outer diameter of the tubular. The radial force is provided by an axial engagement between a setting plate and an upset or shoulder, generally at the end of the shoulder. Using a tapered interface, the axial engagement of the setting plate with the upset in translated into a radially-inward force on the slips, causing the slips to engage the tubular. As noted, another type of elevator utilizes a cable that connects to a lift nubbin which comprises a screw thread which engages with the box end of the tubular, and the lift nubbin and tubular are lifted upwards by the cable.

More particularly, in order to transfer a tubular from a horizontal position (i.e., as stored) to a vertical position (for being made-up and run in) using the so-called lift nubbin, a threaded insert or lift nubbin, is threaded into the swaged box. The lift nubbin has a larger diameter at the top, which serves as the upset for the elevator. While providing adequate tubular placement, this design typically requires the use of a special bored side door to correctly interface with the tubular of the lift nubbin, due to the larger outer diameter of the swaged box. Additionally, slip-type elevators are generally not acceptable for use with the swaged box tubulars, because the taper of the swaged box may cause the slips of the elevator to engage the tapered region of the swaged box, resulting in an incomplete engagement of the outer diameter of the tubular. This, in turn, can result in increased local stress in the areas where the slips engage.

Furthermore, due to the proprietary tubular threads, the prior art so-called nubbins are typically manufactured and provided by the tubular manufacturer. As such, the manufacturer essentially has a monopoly on same and can assign whatever cost basis it desires.

The present disclosure overcomes the disadvantages of presently available tubular lift mechanisms. Accordingly, it is a general object of this disclosure to provide an improved tubular lift device.

It is another general object of the present disclosure to provide a tubular lift ring.

It is a more specific object of the present disclosure to provide a tubular lift ring that can be utilized by any type of tubular, regardless of the manufacturer.

It is still another more specific object of the present disclosure to provide a lockable tubular lift ring.

These and other objects, features and advantages of this disclosure will be clearly understood through a consideration of the following detailed description.

SUMMARY OF THE INVENTION

According to an embodiment of the present disclosure, there is provided a tubular lift ring having an outside and an inside diameter which define an upset for a cooperating elevator. The ring includes internal threads for threading over an end portion of a ring thread machined tubular.

According to an embodiment of the present disclosure there is also provided a tubular positioning combination having a tubular member with external threads on one end and a portion thereof including lift ring threading. A tubular lift ring having an outside and an inside diameter which define an upset for a cooperating elevator. The ring includes internal threads for threading over the end portion of the ring thread machined tubular.

According to an embodiment of the present disclosure there is also provided a method for positioning a tubular for making up a tubular connection including machining a ring threads over a portion of the external threads of a tubular, threading a lift ring having internal threads and an upset, on the portion of the tubular, securing the lift ring in place, engaging the tubular with an elevator having a setting plate that contacts the upset of the ring and then clamps about the tubular, and lifting the tubular into place.

