Apparatus and method for gripping a tubular member

Abstract

Apparatus for gripping a tubular member where the apparatus includes a die and a die holder, and where at least one of the die or the die holder, on its portion facing the other, has at least two axially formed ridges that complementary fit in valleys in the other of the die or the die holder. The ridges have a larger bottom width than top width. The centre lines of the die ridges are substantially parallel at a distance, and the die, when unengaged, is radially movable between abutment of the die ridges to the die holder and abutment of the die to at least one stop member of the die holder.

Claims

1. Apparatus for gripping a tubular member, the apparatus comprising: a die and a die holder, with the die having at least two first ridges and at least two first valleys axially formed on a portion facing the die holder and the die holder having at least two second ridges and at least two second valleys axially formed on a portion facing the die, wherein the at least two first ridges of the die complementarily fit in the at least two second valleys of the die holder, and the at least two second ridges of the die holder complementarily fit in the at least two first valleys of the die, each of the at least two first ridges having a larger bottom width than a top width in a radial direction from the die to the die holder, a lock member movable between a protruding active position and a passive retracted position, wherein the lock member is biased towards the protruding active position which locks the die in the die holder, wherein radial center lines of the at least two first ridges are substantially parallel, and wherein the die, when unengaged from the tubular member, is radially movable between abutment of the at least two first ridges of the die to the at least two second valleys of the die holder and abutment of the die to at least one stop member of the die holder with the die being movable away from the abutment with the at least two second valleys.

2. The apparatus according to claim 1, wherein the at least two second ridges are plough-formed at their upper portion.

3. The apparatus according to claim 1, wherein the at least one stop member comprises a pair of stop members and the pair of stop members forms a dove tail slot.

4. The apparatus according to claim 1, further comprising a magnet, wherein the magnet forms a portion of the at least two first ridges or a portion of the at least two second ridges, and wherein the magnet biases the die toward the die holder when the die is locked in the die holder.

5. A method for gripping a tubular member by use of an apparatus according to claim 1, the method comprising: releasably latching a tool to the die; sliding the die into the die holder; then releasing the tool from the die; gripping and releasing the tubular member; latching the tool to the die; and retrieving the die from the die holder.

6. The method according to claim 5, further comprising releasing the lock member prior to retrieval of the die from the die holder.

7. Apparatus for gripping a tubular member having a longitudinal axis, the apparatus comprising: a die having a first surface configured to face a die holder and having a pair of side surfaces that are tapered toward each other in a radial direction away from the die holder; the die holder having a second surface configured to face the first surface and having two stop members forming a dovetail slot for receiving the die; wherein the first surface comprises at least two first ridges extending substantially parallel to one another in a radial direction toward the die holder, having a bottom width proximal to the first surface that is larger than a top width that is distal from the first surface, wherein the second surface has at least two first valleys extending in the radial direction away from the die, and wherein the at least two first ridges are configured to fit within the at least two first valleys in the second surface; wherein the die comprises a top surface and a pair of bores extending from spaced apart openings in the top surface, each bore including an internal recess spaced from the opening; and a gap between each side surface of the die and a respective one of the two stop members allows radial movement between the at least two ridges and the at least two valleys.

8. The apparatus according to claim 7 further comprising a lock member coupled to the die holder and movable between first and second positions, wherein in the first position the lock member engages the die and holds the die within the die holder, the lock member being biased towards the first position.

9. The apparatus according to claim 8 further comprising at least one support extending away from the second surface from a position axially spaced from the lock member, with the support supporting the die.

10. The apparatus according to claim 7 wherein the second surface comprises at least two second ridges extending substantially parallel to one another in the radial direction toward the die, the second ridges having a bottom width proximal to the second surface that is larger than a top width that is distal from the second surface, wherein the first surface has at least two second valleys extending in the radial direction away from the die holder, and wherein the at least two second ridges in the second surface are configured to fit within the at least two second valleys in the first surface; and wherein the at least two second ridges on the second surface are plough-formed on at least one end.

11. The apparatus according to claim 7 further comprising a magnet positioned at a location selected from the group consisting of the first surface and the second surface.

12. The apparatus according to claim 7 wherein the first surface incudes at least a first pair of ridges and a second pair of ridges, and wherein a distance between the ridges of the first pair is different from a distance between the ridges of the second pair.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) In the following is described an example of an exemplary embodiment illustrated in the accompanying drawings, wherein:

(2) FIG. 1 shows a perspective view of a die and a die holder according to the present disclosure, and where the die is releasably fixed to a tool for inserting the die in the die holder;

(3) FIG. 2 shows a perspective view of the die in its working position in the die holder, and where the tool is released and removed from the die;

(4) FIG. 3 shows a plane view of the die and die holder;

(5) FIG. 4 shows to a larger scale a section from FIG. 3;

(6) FIG. 5 shows the same as in FIG. 4, but in an exploded view;

(7) FIG. 6 shows a section III-III in FIG. 3, a tubular member is not shown;

(8) FIG. 7 shows to a larger scale a section I-I in FIG. 1;

(9) FIG. 8 shows the same as in FIG. 7, but at a preceding stage when a lower body of the tool is entering the die; and

(10) FIG. 9 shows to a larger scale the section III-III in FIG. 3, but with the tool connected to the die.

DETAILED DESCRIPTION OF THE DISCLOSED EXEMPLARY EMBODIMENTS

(11) On the drawings, the reference number 1 denotes an apparatus for gripping a tubular member 2. The apparatus 1 includes a die 4 and a die holder 6. In addition, a tool 8 for inserting or retrieving the die 4 to or from the die holder 6 may be included in the apparatus 1.

(12) The apparatus 1 is part of a gripping device, not shown.

(13) The die 4 has on its tubular member 2 facing side a surface 10 that is prepared to give a good grip on the tubular member 2 when forced against it. On its opposite side, facing the die holder 6, the die has a number of die ridges 12 spaced apart by die valleys 14. The die ridges 12 have a larger bottom width 16 than top width 18. Thus, the die ridges 12 have a tapered form. See FIG. 5 and also FIGS. 3-4.

(14) The die 4 has two side portions 20 that are tapered in the direction from the die holder 6 towards the tubular member 2.

(15) A pair of openings 22 extends into the die 4 from the top surface 24 of the die 4. Each of the openings 22 has a recess 26, see FIGS. 7, 8.

(16) The die holder 6 is on its side facing the die 4 equipped with a number of holder ridges 28 that are spaced by holder valleys 30. The holder ridges 28 and holder valleys 30 are designed to interact with the die ridges 12 and die valleys 14. At least some of the holder ridges 28 are upwardly given a plough form 32.

(17) The die holder 6 is equipped with brackets 34 for fixing the die holder 6 to the gripping device not shown.

(18) Stop members 36 are extending forward on each side of the die holder 6, forming a dove tail slot.

(19) At its lower portion, the die holder 6 has a couple of supports 38. A lock member 40 is positioned at the upper portion of the die holder 6 and is movable between a protruding active position and a passive retracted position. The lock member 40 is biased towards its active position. In alternative embodiments, the lock member 40 may be placed on one of the side portions 20 or at the bottom of the die holder 6, instead of at the upper portion. Placement and retrieval of the die 4 to and from the die holder 6 may also be done by means of bare hands without the use of a specifically designed tool 8.

(20) The shown tool 8, that has a handle or adapter 42, has a pair of lower bodies 44 with pointed ends 46. The bodies 44 are designed to be inserted in the openings and releasably latched in the recesses 26.

(21) When the tool 8 is in its latched position with the die 4, and the die 4 is in the die holder 6, a release member 48 abuts the lock member 40 in its released position, see FIG. 9. The release member 48 is designed to move the lock member 40 from its active to its passive, released position when the tool 8 is inserted in the die 4 with the die 4 in the die holder 6.

(22) When the die 4 is inserted in the die holder 6, the plough form 32 of the holder ridges 28 helps in entering the die 4 into the die holder 6. At the same time, the lock member 40 is moved to its passive position. The die 4 is moved downwardly between the holder ridges and valleys 28, 30 and the stop members 36 until the die 4 rests at the supports 38. The tool 8 is then released from the die 4 by moving the lower bodies 44 first out from the recesses 26, and then out of the openings 22. When the tool 8 is removed, the lock member 40 is free to move into its active, locked position.

(23) As indicated on FIGS. 3 and 4, there is a substantial clearance 50 between the side portions 20 of the die 4 and the stop members 36 of the die holder 6 when the die 4 is engaged in the die holder 6. This clearance allows the die 4 some radial movement in the die holder 6 when the tubular member 2 is released. This feature, together with the tapered form of the die ridges 12 and the fact that the centre lines 52 of the die ridges 12 are substantially parallel with a distance 54, see FIG. 5, render the die 4 unfixed to the die holder 6 even when some deformation of the die 4 is experienced.

(24) The distance 54 may vary between pairs of die ridges 12.

(25) In one embodiment, a magnet 56 is fixed at least at the die 4 or the die holder 6, here at the die holder 6. When unengaged in the die holder 6, the die 4 is biased towards the die holder 6 to avoid matter entering between the ridges 12, 28 and valleys 14, 30 of the die 4 and die holder 6. Such matter could enhance wear.

(26) Removal of the die 4 from the die holder 6 may be undertaken in the reversed sequence from inserting the die 4 into the die holder 6.

(27) It should be noted that the above-mentioned embodiments illustrate rather than limit the invention, and that those skilled in the art will be able to design many alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. Use of the verb comprise and its conjugations does not exclude the presence of elements or steps other than those stated in a claim. The article a or an preceding an element does not exclude the presence of a plurality of such elements.

(28) The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage.