CN2351541Y

CN2351541Y - Non-hoop double-stage synchronous screwed pipe

Info

Publication number: CN2351541Y
Application number: CN 98238701
Authority: CN
Inventors: 王建国
Original assignee: Drilling No2 Co Liaohe Petroleum Exploration Administration
Current assignee: Drilling No2 Co Liaohe Petroleum Exploration Administration
Priority date: 1998-08-27
Filing date: 1998-08-27
Publication date: 1999-12-01
Anticipated expiration: 2008-08-27

Abstract

The utility model relates to a non-hoop double-stage synchronous screwed pipe. The utility model adopts the form that screw thread is connected with a banded pipe body without transition. Pipe diameter and internal diameter do not has radial direction changement in pipe body overall length. When coupling, the utility model is the shoulder connection of two levels and synchronous screw thread. Screw thread teeth adopt cylinder and deflective ladder shape. Bearing angle is 3 DEG, and turning buckle angle is 10 DEG. The radius of the addendum angle of a turning buckle surface is 0.76 millimeters. The utility model is suitable for well tubular piles which has small well tubular pile wall thickness, limited well circular space, large screw thread connection torque, strong anti-slide buckle capability, high tubular pile seal and long service life.

Description

No box cupling has the synchronous screwed pipe of shoulder twin-stage

The utility model relates to a kind of no box cupling that is used for oil drilling the synchronous screwed pipe of step twin-stage, belongs to the well casing material.

Screw thread is that the petroleum and natural gas oil well pipe connects the optimised form that extends and dismantle.Connect in the screw thread series at traditional petroleum and natural gas oil well pipe, all screw threads are one-level and connect form, and mostly with box cupling as the transition between two adjacent bodys.This is in order to satisfy the requirement to linking intensity and high-pressure fluid sealing.For this reason, the variation of the wall thickness of oil well pipe or body and appurtenance internal diameter and external diameter is all bigger, and corresponding increase the in space that tubing string itself is shared is cost with the consumption of sacrificing oil well working space and increase oil well pipe steel consequently.Simultaneously,, make the interference that often takes place in the oil well operation process between oil well support tube column and working string, increased the difficulty of operation technique because the diameter of box cupling much larger than the diameter of body, has destroyed the continuity of tubing string " body ".Typical example is need overlap when milling operation when the packed hole assembly bit freezing occurring in the wellbore construction, because conventional sleeve is milled tubing string for the box cupling transition is arranged, just greatly reduce the borehole wall and quilt cover and milled annular space between tubing string, the milling pipe post will be obstructed or increase cover sometimes and mill workload, increases task difficulty and cost.

Though the two shoulder screw threads that once occurring during the late nineteen eighties also have the advantage that no box cupling has shoulder, also can overcome conventional oil well tubing string screw thread deficiency to a certain extent, but because the carrying angle of its profile of tooth and spinner angle all big (being respectively 7.5 ° and 20 °), make that the self-lock ability of screw thread is lower, because of the carelessness in the elastic deformation in the operation process or connection extension and the field-strip is dismantled screw thread voluntarily, cause serious accident easily.Bigger thread drift angle also makes the threaded portion load situation become badly simultaneously, has increased the trend that internal thread diameter swells, external thread diameter dwindles, and has reduced the ability of screw thread antiskid button in a sense, and this is very dangerous.

The purpose of this utility model can solve above-mentioned all kinds of screw thread pipe defective effectively, and provide a kind of connect that moment of torsion is big, antiskid button ability is strong, self-locking performance good, sealing performance is high OCTG--no box cupling has the synchronous screwed pipe of shoulder twin-stage.

The utility model is achieved in that

The utility model is 4 ¹/ 2 o'clock--9 ³External diameter does not have the direct type of attachment of position employing body that is threaded of the oil drilling tubing of radial variations in/4 o'clock, manufacture and form, be that the tubing string screw thread is no transition box cupling, the tubing string internal and external threads does not adopt the transition box cupling, add and directly to be processed into the male thread other end box thread man-hour, just can need not to be equipped with appurtenance again at connection body two ends or to carry out jumping-up and handle at body one end.

Tubing of the present utility model connect adopted twin-stage, synchronously, the shoulder screw thread arranged; Be the internal thread of tubing string and external screw thread are processed as screw thread incision orientation respectively and entrance angle identical, and have identical flute profile, an identical isoparametric twin-stage screw thread of pitch, make the strength ratio of internal and external threads at different levels identical, screw thread form is cylinder, buttress thread, trapezoidal angle is respectively 3 degree and 10 degree, screw thread adopts cylinder but not conical form, and all with arc transition, spinner face tooth top arc radius is 0.76 millimeter at each position of screw thread.

The utility model advantage is:

Because the utility model has adopted:

Screw thread does not have the transition box cupling, body direct connection form, the tubing string internal and external threads does not adopt the transition box cupling, and directly on body, process, need not to be equipped with again appurtenance or carry out jumping-up and handle at the body two ends, not only reduced machining process and steel consumption amount, helped reducing production costs, and the mechanical performance that can guarantee the tubing string material effectively is not subjected to the influence of extraneous factor.Especially help reducing the cross-sectional area and the occupation space of tubing string, for the working space of oil well has left bigger leeway, the difficulty of operation in the oil well pipe is descended, operation technique becomes simple.

On the external diameter and internal diameter total length of tubing string, all there is not radial variations in addition.All are same diameters inside and outside the caliber, have good " body " continuity, whole tubing without any boss and depression.Inside and outside " body " the good continuity of tubing string helps the raising of tubing string axially-movable degree of freedom in oil well, the tubing string axial freedom is higher, mutual collision and possibility of interference are littler between oil well pipe, more help preventing oil well wall jam, have improved the safety in the oil well operation process.

The uniformity of oil well pipe internal diameter also advantageously prevents the pressure loss and the change in flow of oil well fluid, and this is for preventing the eddy generation of oil well fluid, guaranteeing that tube wall is extremely promising not favourable by erosion attack.

The utility model has adopted " twin-stage, synchronously, the shoulder thread connection arranged " when mode also will be satisfied with because of the oil well operation, and the down-hole limited space is to down-hole steel strength and the requirement of strength that is threaded, bigger specific (special) requirements.

The utility model is provided by following examples

Illustrated below in conjunction with accompanying drawing

Accompanying drawing: the utility model structural representation

A kind of no box cupling has the synchronous screwed pipe of shoulder twin-stage; It is characterized in that with the tube column after this pipe connection be the direct connection form, the tubing string screw thread is no transition box cupling, the pin thread of this tubing string external diameter 1 and internal diameter 10 and the location shoulder 2 that car has 90 to spend above box one end tube wall 8 contact jaws, thread tooth is a cylinder, trapezoidal partially: trapezoidal angle is respectively 3 degree (carrying angle 4) and 10 degree (spinner angle 3), internal thread 5,9

external screw threads

6,7 each one are all with arc transition, 3 the tooth top arc radius in spinner angle are the R0.76 millimeter, this screw thread has adopted twin-stage when connecting, synchronous screw thread, it is that to avoid occurring the intensity of a double thread and rigidity for fear of the tubing string that connects each other inconsistent and the situation a certain position initial failure that causes takes place that the shoulder bind mode is arranged, and replenishes mutually between the two-stage screw thread and strengthens but make.Adopt synchronous screw thread to help inside and outside twin-stage screw thread and screw in simultaneously and put in place, prevent mutual interference.Employing has the shoulder thread forms, the location after helping internal and external threads and screwing and the sealing of convection cell.Contact pressure between the internal and external threads shoulder is enough big, can effectively prevent escape of liquid, this connects, prevents to be destroyed by fluid erosion significant for the safety that guarantees screw thread, in addition, screw thread of the present utility model adopts cylinder, buttress thread, and trapezoidal angle is respectively 3 degree and 10 degree.Screw thread adopts cylinder but not conical form can reduce the wall thickness of tubing string as far as possible, to adapt to the less requirement of tube wall.The flute profile of screw thread adopts trapezoidal partially the screwing and big bearing capacity of screw thread that help, especially carry the angle and adopt 3 degree, can reduce the radial component of thread under the top load state to greatest extent, the trend of hole enlargement that the reduction external thread diameter shrinks and internal thread diameter swells helps improving the stability of screw thread and the ability of antiskid button.

In this outer tube body footpath 10 " each one of screw thread is all with arc transition, spinner face tooth top circular arc radius R 0.76mm ".The transition arc at each position of screw thread helps reducing the tubing string surface to be destroyed because of machining screw " " the formed factor of stress concentration of the continuity of profile, this is most important for fatigue limit and dependability of improving the screw thread position body.It is 10 degree and spinner face tooth top circular arc radius R 0.76mm that the rational transition arc in screw thread position can make spinner angle, tubing string two ends, screws in when helping thread connection, is difficult for taking place complex situations such as thread alternating; Simultaneously can reduce the wearing and tearing that screw thread screws thread in the process, prevent that the metal fines that produces in the thread abrasion process from causing the bonding between the screw thread flank.

Claims

1, a kind of no box cupling has the synchronous screwed pipe of shoulder twin-stage; It is characterized in that: the tube column that connects with this pipe is the direct connection form, the tubing string screw thread is no transition box cupling, the pin thread of this tubing string external diameter (1) and internal diameter (10) has one 90 degree location shoulder (2) with box one end tube wall (8) above the contact jaw, thread tooth be cylinder, trapezoidal partially, carry angle (4) and spinner angle (3) and internal thread (5), (9), external screw thread (6), (7) each position all are arc transition.

2, screwed pipe according to claim 1; The face tooth top arc radius that it is characterized in that spinner angle (3) is the R:0.76 millimeter.

3, screwed pipe according to claim 1; It is characterized in that this pipe connects for twin-stage, screw thread has the shoulder bind mode synchronously; Screw thread form is cylinder, trapezoidal partially, and its trapezoidal angle is 3 degree and 10 degree.