JPS621344Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a slip insert piece in a support device for a long continuous pipe such as a drilling pipe of an oil drilling rig.

Drilling pipes for oil drilling rigs are made by connecting a number of iron pipes with bits attached to the bottom end for several thousand meters and suspending them from the rig installed on the ground or offshore.
The overall weight is very large, so the support needs to be extremely strong.

When connecting or removing a tunnel, temporarily secure the upper end of the tunnel below the connection to a rotary table.
The next pipe is connected to or removed from it. In this case, a supporting stand is usually installed as shown in Fig. A wedge-shaped slip 4 divided in the circumferential direction between the tapered surface 2 of 1 and the tunnel 3
is inserted, and if the tube 3 tries to move downward under its own weight, the slip 4 tightens the tube 3 due to the wedge action.
In addition, a groove 4a having a trapezoidal cross section and a flat bottom surface is provided on the inner surface of the slip 4, and the curvature of the surface 6 that comes into contact with the trench pipe 3 is made to match the curvature of the surface of the trench pipe 3, and a large number of protrusions are provided on that surface. By fitting and attaching a required number of the provided insert pieces 5 from the upper end, the above-mentioned protrusions bite into the surface of the tunnel 3 to prevent slippage and ensure support of the tunnel.

Conventionally, the insert piece 5 has been positioned by cutting the back surface 7 into a flat surface and placing it in close contact with the bottom surface of the groove 4a of the slip 4, so that the relative position of the insert piece 5 with the surface that contacts the front pipe can be accurately determined. I needed to finish it. However, the surface of the pipe itself is not highly accurate, and the relative position of the slip to the support is also not highly accurate. They do not make contact, resulting in what is called uneven contact, and excessive pressure is applied to a part of the pipe, and the protrusion of the insert digs into that part excessively, causing damage.
This was one of the causes of premature pipe wear.

This device is easy to manufacture and eliminates the above-mentioned drawbacks of conventional slip insert pieces in support devices for very heavy pipes such as oil drilling pipes. To provide a slip insert piece that can reliably support a pipe.

Hereinafter, the present invention will be explained in detail based on drawings showing embodiments thereof.

In the insert piece 10 of the embodiment shown in FIGS. 2a, b, and c, the front surface 11 that comes into contact with the pipe is formed as a part of a cylindrical surface that matches the curvature of the surface of the pipe, similar to the conventional one, and is provided with countless protrusions 12. Further, both side surfaces 13 have a taper that matches the shape of the mounting groove of the slip. However, the back surface 14 is formed as a part of a spherical surface with a large radius, and is a convex surface with the center portion slightly protruding from the peripheral portion. Its protrusion is 10cm
It is appropriate that the length be approximately 1 to 1.5 mm in the length direction.

Therefore, as shown in FIGS. 2b and 2c, the back surface protrudes at the center in both the vertical and horizontal directions and makes point contact with the bottom surface of the mounting groove. Therefore, even if the surface precision of the pipe is not high, the insert piece can roll in any direction at the point of contact with the bottom of the mounting groove on the back surface, and the front surface 11 applies uniform pressure to the entire surface of the pipe. They touch each other, and no excessive pressure is applied locally. Since the insert piece has sufficient thickness in relation to its width and length, there is no risk of deformation or breakage even if the back side is supported at one point.

The curved surface on the back surface of the insert piece is not limited to a part of a spherical surface, but the object of the present invention can be achieved as long as it is a convex curved surface with a central part protruding outward. You can.

Moreover, as shown in FIG. 3, the insert piece 15
When the back surface 15a of the insert piece 16 is made a part of a cylindrical surface having an axis parallel to its longitudinal direction, the insert piece can swing around a vertical axis, and as shown in FIG. When the insert piece is made a part of a cylindrical surface having an axis perpendicular to its longitudinal direction, the insert piece can swing around the horizontal axis, and the poor accuracy in each direction is compensated for, and a certain effect can be obtained.

Since the insert piece is generally finished by machine cutting, it is impossible to finish the back surface into a curved surface, especially a three-dimensional curved surface such as a spherical surface. However, it is extremely easy to create such a curved surface using precision casting.

As described above, according to the present invention, even if the dimensional and shape accuracy of the insert piece itself, the mounting groove, and the pipe are somewhat poor, the front surface of the insert piece can be brought into uniform contact with the pipe over the entire surface, and the support of the pipe is improved. become certain.

The present invention is not limited to temporarily supporting a dug pipe on a rotary table, but can also be used as an insert piece for various pipe support devices such as a tong die installed on the gripping surface of a tong that grips a pipe attached to the upper end of the tong. can.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an example of a conventional pipe support device, and FIGS. 2a, b, and c are a front view, a side view, and a top view of an insert piece according to an embodiment of the present invention, respectively.
3 and 4 are perspective views showing other embodiments of the present invention, respectively. 1... Support stand, 2... Tapered surface, 3... Pipe, 4... Slip, 4a... Insert piece mounting groove, 10, 15, 16... Insert piece.

Claims (1)

[Claims for Utility Model Registration] (1) A pipe support device that has a wedge-shaped slip wedged between the tapered surface of the support and the surface of the pipe to be supported, and is attached to the surface of the slip facing the pipe and attached to the pipe. In an insert piece where the abutting surface is a curved surface that matches the surface of the pipe and many protrusions are provided on that surface, the back surface of the surface that abuts the pipe is a convex curved surface where the center part is slightly bulged out from the peripheral part. An insert piece characterized by: (2) The insert piece according to claim 1, wherein the curved surface of the back surface is a part of a spherical surface. (3) The insert piece according to claim 1, wherein the curved surface of the back surface is a part of a cylindrical surface having an axis parallel to the insertion direction of the insert. (4) The insert piece according to claim 1, wherein the curved surface of the back surface is a part of a cylindrical surface having an axis perpendicular to the insertion direction of the insert.