RU128912U1 - DRILL PIPE WITH VARIABLE INTERNAL SECTION LOCKS (OPTIONS) - Google Patents

Abstract

1. A drill pipe with locks of variable internal section, including the pipe body with a diameter of 89 mm with upset ends and with a nipple welded to them and a lock sleeve with a diameter of 105.5-108 mm, interconnected by a trapezoidal conical thread (pitch - 8.467 mm, taper 1: 9.6, angle at the apex of the thread - 90 °) with one external stop, characterized in that the diameter of the inner hole of the nipple in the interval of its thread, equal to 50-53 mm, is smaller than its internal diameter in the interval of welding, shank and inner diameter couplings, while on the output de fluid from the pin configured cone, and the clutch - zarezbovaya conical boring length of at least 51 mm, which taper 1: 9,6.2. Drill pipe with locks of variable internal cross section, including the pipe body with a diameter of 89 mm with upset ends and with a nipple welded to it and a lock sleeve with a diameter of 105.5-108 mm, interconnected by means of a trapezoidal conical thread (pitch - 8.467 mm, taper 1: 9.6, the angle at the apex of the thread 90 °) with two stops - external and internal, characterized in that the internal opening of the nipple and the internal opening of the coupling with a diameter of 50-53 mm adjacent to the internal stop are smaller than the internal opening of the nipple and the coupling adjacent to sv rku (lock shank and pipe upset), while the transition from the smaller hole of the coupling adjacent to the inner thrust plane to its larger hole adjacent to the welding is made in the form of a diffuser, and the outer contour of the inner thrust end of the nipple is mated to the reciprocal inner thrust ledge couplings on a rounded surface.

Description

The claimed utility model relates to the field of mining, namely to drill pipes (BT), intended mainly for drilling, emergency work and overhaul in wells cased with pipes of 140-168 mm in size.

In connection with the construction of horizontal and highly curved wells, additional requirements are imposed on drill pipes due to the necessity of moving (passing) within them geophysical instruments of a certain diameter and the ability of the pipes to transmit high torque and axial compressive load to the bottom. Therefore, drilling organizations in the aforementioned casing strings instead of BT with a diameter of 73 mm began to use stiffer pipes with a diameter of 89 mm with an internal upset and locks of a reduced size.

Known drill pipe size 89 × 8 mm with welded locks ZP-105-53, thread 3-86 (TU 14-161-137-94), the torsion moment of the locks which are significantly lower than the moment of torsion of the pipe body. Stronger pipes PV-89x9.4 mm with locks ZP-108-44 (GOST R 50278-92, table 1) are known, but the internal hole in the locks, equal to 44.5 mm, does not allow existing geophysical instruments to be lowered into the well.

When reducing the outer diameter of the lock, the diameter of its inner hole automatically decreases, which in standard design locks leads to an increase in the wall thickness of the upset pipe end to which the lock is welded. If the ratio of the cross-sectional area of the upset to the cross-sectional area of the body of the pipe (upsetting coefficient K _in ) is more than 2.2, then the surface of the inner cone of the upset portion of the pipe is steep and uneven, which reduces its strength and leads to an increase in local hydraulic resistance. The landing coefficient K _{in the} BT blanks for welding to the above ZP-108-44 lock is 2.45.

In order to increase the working moment of torsion, threaded locking joints with two stops - external and internal - are distributed. The use of the second internal stop allows you to increase the torsion moment of the threaded connection by 30-40% without increasing the outer diameter of the lock.

Closest to the claimed utility pipe model with one stop in the thread according to the technical nature (prototype) is a drill pipe with a high-torque lock (options) [RF patent No. 53405, IPC F16L 9/02, publ. 05/10/2006, Bull. No. 13], which includes the body of the pipe 89 × 8 mm in size with upset ends and a sleeve and nipple welded to them with a diameter of 105 (108) mm with a connecting lock thread, having the following parameters: thread pitch - 8.47 mm, taper - 1: 9, 6, the angle at the top of the thread is 90 °.

The disadvantage of these known pipes is that the inner hole of the nipple and socket ends of the drill pipe along the entire length, including the lock, welding and upsetting, has a constant diameter of 51.5 mm. In this case, the landing coefficient K _{in the} pipe billet for welding the locks is 2.5, which exceeds the preferred value. Patented drill pipes measuring 89 × 8 mm with a high-torque lock in torsional strength correspond only to pipes of the strength group E and L, which does not meet the requirements for drilling deep horizontal wells.

Closest to the claimed utility model of pipes with two stops in the castle connection by technical nature (prototype) is the connection of the drill string [RF patent No. 88729, IPC E21 B 31/00, publ. 01/10/2010, Bull. No. 1], including a tapered thread provided with internal and external stops, and the internal stop is made of at least 10 mm The drill string connection with two stops was developed on the basis of widely used standard threads, the taper of which is 1: 6, the pitch is 6.35 mm, and the angle at the tip of the thread is 60 °.

The inner hole in the nipple and the coupling of the connection has a constant size along the entire length, which in some sizes of small diameter drill pipes (60; 73 and 89 mm) makes it difficult to make a stable second thrust belt. In patent No. 88729, a kinematic diagram of a known connection of a drill string with two thrust stops is given, but design parameters are not indicated in cross sections to achieve the desired result.

A useful model solves the problem of creating a structurally simple drill pipe with a diameter of 89 mm with welded locks, the outer diameter of which is a maximum of 108 mm, and the inner hole of at least 50 mm, which has increased fatigue strength and lower hydraulic resistance during flushing fluid flow.

This problem is solved due to the fact that in the drill pipe according to the first embodiment, Fig. 1, comprising a pipe body with upset ends and welded locking parts, on which a trapezoidal conical thread with one external stop and a threaded conical bore in the lock sleeve is made, the diameter of the inner hole of the nipple in the thread interval is less than the diameter of the inner holes in the coupling and in the pipe fittings. The transition from a reduced hole in the nipple to an enlarged hole in the coupling is made in the form of a diffuser.

This problem is solved due to the fact that in the drill pipe according to the second embodiment, Fig. 2, comprising a pipe body with upset ends and welded locking parts, on which a trapezoidal tapered thread is made with two stops - an external and an internal, with an internal hole the nipples and couplings in the interval adjacent to the plane of the second stop are smaller than the inner holes of the nipples and couplings in the interval of the shank 4 of the lock and weld 14. The increase in the inner hole in the interval of welding allows you to optimize the value of the coefficient of landing K _{in the} pipe.

The transition from the reduced hole dm of the coupling adjacent to the second abutment plane 10 to its enlarged hole d ' _m adjacent to the welding 14 is made in the form of a diffuser 12.

The design of the drill pipe is shown in the drawings:

figure 1 - General view of the drill pipe according to the first embodiment;

figure 2 - General view of the drill pipe in the second embodiment;

figure 3 - the nipple and the coupling of the drill pipe in assembled form according to the first embodiment;

figure 4 - the nipple and the coupling of the drill pipe in assembled form according to the second embodiment.

The drill pipe with a diameter of 89 mm according to the first embodiment (Fig. 1) includes a pipe body 1 with upset ends 13, welded along the shank 4 of the sleeve 2 and nipple 3 with a trapezoidal tapered thread 5 and external thrust surfaces 6. A threaded bore 8 is made under the sleeve 2 under a slope angle (φ with the internal thread surface 5. The length l _{to the} bore of at least 51 mm, the bore 8 is conjugate with an inner hole d _'m couplings second conical bore 9, the slope angle (3 is 15 ° (Figure 3).

The adopted design of the threaded bore in the coupling allows to reduce the stress concentration in the area of transition from the internal thread 5 to the inner hole d ' _{m of the} coupling 2.

The diameter d of the inner hole in the nipple 3 is less than the diameter of the inner hole d ' _m in the sleeve and the upset ends of the pipe adjacent to welding 14. This solution allowed to reduce the thickness of the upset wall and, as a result, to improve the quality of the conical transition from the upset and the body of the pipe. The small length of the narrowed hole d _n in the nipple 3, the presence of a diffuser 7 at the outlet of the liquid from the nipple can reduce local hydraulic resistance in the locks.

The drill pipe in the second embodiment (FIG. 2) differs from the drill pipe in the first embodiment in that the thrust connection additionally has an internal stop 10. The wall thickness of the thrust band 11 is at least 6.6 mm, the radius of curvature rm along the intersection line of the cylindrical bore dp and the abutment plane 10 in the coupling is 3 mm, FIG. 4, view I. The radius of the radius of rounding of the angle of the abutment band 11 is 1.2 mm. The contacting contact surfaces 10 of the nipple and the coupling smoothly diverge in their radius of curvature, Fig. 4, view I. Since the resistant surfaces of the nipple and the coupling repeatedly compress at very high contact stresses, and during drilling they additionally experience bending alternating loads, the contact belt 11 of the nipple having no smooth rounding, as is done in the known prototypes, with its external angle or chamfer will crash into the counter surface of the coupling, causing local damage that develops when will lead to failures along the plane 10 of the coupling.

As in BT according to the first embodiment, the inner hole dн in the nipple in the interval of its thread is smaller than its inner hole d'H adjacent to the weld 14. The diameter dm of the inner hole in the coupling adjacent to the abutment surface 10 is equal to the diameter of the counter hole da in the nipple . The transition from the reduced hole dm in the coupling to its enlarged hole m adjacent to the welding 14, is also made in the form of a diffuser 12, (figure 4). The diameters d'm d'n of the hole in the coupling and nipple are determined based on the preferred value of the landing coefficient Kv.

The nipple and the coupling of the drill pipe lock in the second embodiment are assembled in FIG. 4. The flow of flushing fluid, moving inside the drill string, smoothly compresses in the upsetting of the nipple end of the pipe and in the nipple, passes through a smooth channel with a constant inner diameter dp and dm and gradually expands in the diffuser 12 and in the upset 13 of the sleeve end of the pipe. The proposed design of the drill pipe allows to reduce hydraulic resistance in the locks in comparison with the analogue in half.

Table 1 optionally gives an example of the main structural parameters of a pipe with a drill size of 89 × 8 mm and 89 × 9.35 mm with welded locks ZP - 108-51 of the first and second embodiments according to Fig.1 and Fig.2. The characteristics of these pipes are shown in table 2.

Drill pipes with a size of 89 × 9.35 mm of grade L and M in terms of torsional strength are optimally balanced only with ZP - 108-51 locks with two stops in a threaded connection. The ratio of the torsion moment of the lock to the moment of torsion of the pipe only in this case meets the criterion

where Mkr.zam. - the moment of torsion of the lock;

Micr. - the moment of torsion of the pipe.

Figure 3 and table 3 optionally given the main dimensions of the lock with one emphasis, figure 4, 4-1 and table 4 - the dimensions of the castle with two emphasis. The profile parameters of the trapezoidal conical thread correspond to the SL-H90 thread given in API-70 Standard Recommended Practice for Drill Stem Design and Operating Limits, sixteentn edition, 1998, Table A - 1, i.e. the thread pitch is 8.467 mm (8 threads on a length of 25.4 mm), the taper is 1: 9.6, the angle at the top of the thread is 90 °.

The thrust belt 11 withstands an axial compressive load of 1170 kN, which exceeds the axial load from the torque perceived by the second stop.

должно быть в пределахThe ratio of the moment of resistance of the coupling to the moment of resistance of the nipple for the proposed threaded connection with locks with a diameter of 105.5 and 108 mm mm is 2.35 and 2.58, respectively, i.e. the joint meets the criterion of bending strength. For an optimally balanced lock connection relationship

should be within

where Wm is the moment of resistance of the coupling;

Wн is the moment of resistance of the nipple.

In order to provide the possibility to lower modern geophysical instruments into the well through the borehole, the diameter dн of the internal hole of the lock according to the first and second embodiments, depending on the size and grade of the steel of the drill pipe, is 50-53 mm.

According to the manufacturing method, the claimed drill pipe does not differ from the method of manufacturing standard pipes.

The analysis of the prior art by patent and scientific and technical sources containing information about analogues, the applicant has not identified the design of the drill pipe is identical to all the essential features of the claimed utility model.

Thus, the proposed utility model, in combination with its essential features, characterized by an optimal balance of torsional strength, bending and compressive strength, as well as increased fatigue strength, allows the assembly to increase the operational reliability of drill pipes and reduce pressure losses in the joints during washing wells.

Table 1 - The main parameters of the drill pipe with locks of variable internal section with one and two stops in the thread Size Pipe wall thickness, § Inner diameter The landing coefficient, SQ Option pipes the castle nipple couplings dH d'H dM d'M BV * -89 ZP-108-51 8.0 50.8 60 - 60 1.88 First, FIG. one BV-89 ZP-108-51 9.35 50.8 55.8 50.8 55.8 1.80 Second, FIG. 2 Note: Kv is the upsetting coefficient equal to the ratio of the upsetting area to the pipe body area. In the example for both variants, the landing diameter db is 92 mm. * BV - drill pipe with internal upsetting.

Table 2. Characteristics of drill pipes with locks of variable internal cross-section Name of parameters Pipe BV-89 × 8.0 Pipe BV-89 × 9.35 pipe grade ZP-108-51 lock with one emphasis pipe grade ZP-108-51 lock with two stops E L L M Tensile load Q, corresponding (7 t, at Мкр = 0, kN 1051 1331 2227 1530 1691 2227 The torsion moment Mkr, corresponding to, at Q = 0, kN 22.5 28.5 22 31.8 35,2 29.5 Ratio Mkr.zam / Mkr.tr 1,0 0.8 - 0.9 0.8 - Table 3. The main dimensions of the threaded connection with one stop dimensions in mm Lock size Diameter Length β holes threaded bore, d _K total lm threaded boring, lк nipple, d _H couplings, d ' _M ZP-108-51 50.8 60.0 63.6 155 51 15 ° Table 4. The main dimensions of the threaded connection with two stops dimensions in mm Lock size Diameter Length Radius coupling and nipple holes, d _H and d _M thrust belt, d _n thread in the plane of the end face of the nipple, d ₃ l l _p r _m r _p ZP-108-51 50.8 66,2 72,2 112.7 12.7 3.0 1,2

Claims (2)

1. A drill pipe with locks of variable internal section, including the pipe body with a diameter of 89 mm with upset ends and with a nipple welded to them and a lock sleeve with a diameter of 105.5-108 mm, interconnected by a trapezoidal conical thread (pitch - 8.467 mm, taper 1: 9.6, angle at the apex of the thread - 90 °) with one external stop, characterized in that the diameter of the inner hole of the nipple in the interval of its thread, equal to 50-53 mm, is smaller than its internal diameter in the interval of welding, shank and inner diameter couplings, while on the output de fluid from the pin configured cone, and the clutch - zarezbovaya conical bore is not less than 51 mm, which taper of 1: 9.6. 2. A drill pipe with locks of variable internal section, including the body of a pipe with a diameter of 89 mm with upset ends and with a nipple welded to them and a lock sleeve with a diameter of 105.5-108 mm, interconnected by a trapezoidal conical thread (pitch - 8.467 mm, taper 1: 9.6, angle at the apex of the thread 90 °) with two stops - external and internal, characterized in that the inner hole of the nipple and the inner hole of the coupling with a diameter of 50-53 mm adjacent to the internal stop are smaller than the inner hole of the nipple and the coupling, adjacent to cooking (lock shank and pipe upset), while the transition from the smaller hole of the coupling adjacent to the internal stop plane, to its larger hole adjacent to the welding, is made in the form of a diffuser, and the external contour of the internal stop face of the nipple is mated to the reciprocal internal stop ledge couplings on a rounded surface.

Images