DE1233798B - Stop ring that can be attached to drill pipes - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

EDITORIAL

Int. CL:

E21b

German KL: 5a-17/10

Number: 1233 798

File number: W 38918 VI a / 5 a

Filing date: April 7, 1965

Opened on: February 9, 1967

The invention relates to a stop ring with only one separation point, which is on the outer wall of drill pipes, can be fixed in particular on casing pipes.

It is known to use tools and equipment such. B. centering baskets and scrapers, loosely on the casing tubes to postpone and to limit the freedom of movement in the axial direction by means of stop rings, which are fixed at the desired location on the outer wall of the pipe.

For stop rings of casing pipes in deep boreholes, it is essential that the ring does not protrude Has parts, so that the one available even with a narrow casing pipe gradation relatively narrow annular space as largely as possible with the supporting material of the stop ring can be filled out and a high resistance to displacement of the stop rings on the pipe is achieved will.

The stop ring according to the cited US Pat. No. 3,028,182 has a locking device shown with a T-shaped tab. The ring shown in the figures consists of two Halves that are attached to the pipe from opposite sides by the T-shaped locking device is loosely inserted in the closed position and the second T-shaped, but longitudinally movable tensionable T-shaped locking device is also loosely inserted. Be in this locking device V-shaped pressure pieces 40, 41, bent in the longitudinal direction, are inserted, which by hammer blows into transferred to the stretched position so that the ring is narrowed. That’s a certain one Clamping process secured, but no automatic compensation of the tolerances of the pipes and clamping ring parts present, so that no tight fit of the clamping ring can be achieved in every case. For this rather, terminal blocks are arranged under rivet-head-like widenings of the ring, their edges should penetrate into the surface of the pipe when tensioning the ring. As from the overall arrangement clearly visible, this penetration can only after a corresponding oval deformation of the ring occur, so that it can easily happen that only an apparent fixed tension of the ring is present because the ring is still partially exposed on the circumference is located. Furthermore, wear the terminal blocks significantly, so that the ring is always for a predetermined Feed ring gradation must be made thinner accordingly and therefore the maximum possible strength cannot be achieved.

From the German patent specification No. 1016 204 is Stop ring that can be attached to drill pipes

Applicant:

Weatherford Oil Tool G.m.b. H., Krähenwinkel 29 on Hanover

Named as inventor:

Wilfried Dreyfuss, Wennigsen; Dipl.-Ing. Friedrich Heinrich Langer, Hanover; Roy K. N. Fox,

Brentwood, Essex (Great Britain); Hugo Wagner, Krähenwinkel about Hanover - -

It is also known by using something special Material necessary to increase the friction between the ring and the pipe To get seat, the turnbuckles, be it in the form of a hinge, a locking piece or a simple hook after tensioning with a tensioning lever to a predetermined end diameter of the ring. The tolerances of the pipe outer diameter and the ring diameter can thus only taken up by the correspondingly thick elastic pads of the ring and be balanced, so that by no means an optimal clamping force is achieved.

A known stop ring consists of an annular piece of pipe of the appropriate diameter, an annular groove is incorporated into the inner wall. Openings open into the groove a, which establish a connection to the outer wall of the stop ring. The ring goes onto the pipe pushed on and fixed at the desired point by nails, which are tangential through the openings are driven into the annular groove. The inner diameter of such stop rings may be this system must be only slightly larger than the outer diameter of the pipe on which it is fixed should be.

The pipes and rods used in deep wells are highly stressed, so that in their The best possible material utilization is to be aimed for in the construction. The greatest stress is there mostly in the area of the thread connection of two pipe sections, as the thread reduces the

709 508/49

Claims (1)

tion of the load-bearing material cross-section occurs. In order to remedy this disadvantage, more and more drill pipes have recently been designed with threaded sockets with a reinforced material cross-section. The undivided stop rings previously used can no longer be pushed onto the pipes due to the larger diameter of the sleeves, so that they can no longer be used for the pipes with reinforced sleeves. The invention therefore has the task of designing a stop ring so that it can be pushed onto the pipe via thickened pipe ends and yet results in the most complete possible use of the free annular space for the supporting material. This is achieved for a stop ring with only one separation point in that the ring has a single, known T-shaped locking device formed from a tab and tongue and is provided with an inner ring groove for tensioning, into which one or more nails can be driven from the outside are, the annular groove is interrupted in the area of the separation point. The crosspiece of the T-shaped bracket and recess is expediently inclined in a dovetail shape so that the parts which essentially transmit the force are prevented from slipping off when the ring is tightened or when the ring is loaded. In a further embodiment, the parts of the ring that have remained standing on both sides of the T-shaped middle parts of the end pieces are equipped with end faces offset from one another in a Z-shape, which cause additional lateral guidance of the ring lock. In an advantageous further development, the end pieces on the central web of the Z-shaped offset end faces also have dovetail-shaped noses, so that these parts of the ring material are also used for power transmission via the separation point (lock). Such a ring can be pushed in the open state over the reinforced sleeves of a casing and z. B. be compressed so far by collets that the T-shaped tab is above the T-shaped recess of the other end piece. The T-shaped tab can then be pressed down or driven into the recess by striking a hammer, so that the lock connects the two ring ends with one another in a non-positive and positive manner. The final fastening of the now closed stop ring on the casing takes place by means of nails which are driven tangentially through openings in the stop ring into an annular groove which is preferably interrupted in the area of the lock. The invention is explained in more detail below with reference to the representation of an exemplary embodiment in the accompanying drawings. 1 shows a plan view of the lock point of a stop ring pushed over a casing pipe in the open state, FIG. 2 shows the ring according to FIG. 1 in the closed state of the lock, and FIG. 3 shows a longitudinal section through the stop ring according to FIG. 2 along the line A -A. According to FIG. 1, a stop ring 2 is pushed onto a casing 1 in the open state. The stop ring 2 has end pieces 3 and 4 at a separation point, which can be connected to one another in a non-positive and positive manner by a lock. For this purpose, the end piece 3 runs out into a T-shaped tab, which consists of a web? and a cross piece 6 is formed. In the opposite end piece 4 there is a T-shaped recess corresponding to the tab 6, 7 with a web 7 'and a cross piece 6'. The lower side surfaces 8 of the cross pieces 6 and 6 'are inclined in a dovetail shape against the direction of force. To avoid local overstressing of the material, the transition point of the web 7 into the dovetail-shaped inclined surface 8 is designed as a rounding 9. On the end piece 3, a guide piece 10 is also arranged on both sides of the T-shaped bracket, which guide piece engages in corresponding recesses 10 'of the other end piece 4 when the lock is closed. Appropriately, the width of the web 7 is somewhat smaller than the width of the parts 5 of the ring 2 left standing next to the crosspiece 6 ', so that even with one-sided loading (buckling loading) a more even distribution of the loading on the material occurs. The stop ring 2 is pushed onto the casing 1 z. B. compressed by a suitable pair of pliers that the T-shaped tab 6,7 of the end piece 3 on the end piece 4 comes into a position in which the crosspiece 6 is above the recess 6 '. With hammer blows in the direction of the casing 1, the tab 6, 7 is then pushed into the corresponding recesses 6 ', T of the other end piece 4, as shown in FIG. 2 shown, settled. The lock is now in its closed position. After removing the forceps pressure, the stop ring can still be moved in the axial direction on the casing pipe. To fix the stop ring 2 at the desired location of the casing 1, nails 14 are driven in a manner known per se through openings 12 tangentially into an annular groove 13 recessed from the inner wall of the stop ring 2 according to FIG. In particular, due to the omission of the annular groove in the area of the lock when the nails are driven in, the lock area is pressed firmly against the outer wall of the casing so that the T-shaped tab cannot swing out of the plane of the stop ring. In the one shown in FIG. In the closed state of the stop ring 2 shown in FIG. 2, the parts that correspond to the parts shown in FIG. 1 are provided with the same reference numerals. In the lower half of the stop ring shown in FIG. 2, there is a further development of the guide pieces 10 and 10 'from FIG. 1 for the additional transmission of longitudinal forces, in that the guide pieces 10 and 10 'are also equipped with dovetail-shaped noses 11 and 11' on the side surfaces directed towards the center of the ring. Patent claims: 1. Stop ring that can be attached to drill pipes with only one separation point, marked