CN102322989B

CN102322989B - Device for measuring radial pressure of underground sucker rod

Info

Publication number: CN102322989B
Application number: CN 201110236526
Authority: CN
Inventors: 王中宇; 王岩庆; 王旭; 吕长宏
Original assignee: Beihang University
Current assignee: Beihang University
Priority date: 2011-08-17
Filing date: 2011-08-17
Publication date: 2013-06-19
Anticipated expiration: 2031-08-17
Also published as: CN102322989A

Abstract

The invention belongs to the technical field of metering and testing, and relates to the improvement of a device for measuring the radial pressure of a sucker rod when an eccentric wearing phenomenon occurs between the underground sucker rod and an oil tube. The improved device comprises a pup joint, sealing rings, a ring bush, a resistance strain gauge and an integrated circuit system, and is characterized in that the pup joint of a through-hole type is provided; two sections of internal threads are respectively arranged at the two ends of the through-hole; ring grooves are respectively arranged at the inner ends of the internal threads; the sealing rings are placed in the grooves; the elastic ring bush is clung to the inner surface of the through-hole of the pup joint; the resistance strain gauge is stuck to the inner surface of the ring bush; and the integrated circuit system is mounted at the inner part of the pup joint. According to the device disclosed by the invention, the measured maximum radial pressure is 500KN, the measured minimum radial pressure is 10N, the maximum withstand voltage is 35MPa, and the highest working temperature is 120 DEG C.

Description

A kind of device for measuring radial pressure of underground sucker rod

Technical field

The invention belongs to the metrological testing technology field, relate to the improvement of sucker rod device for measuring radial pressure when between underground sucker rod and oil pipe, the eccentric wear phenomenon occuring.

Background technology

The advantages such as the oil pumping mode that generally adopts both at home and abroad at present is sucker rod pumping, and it has, and cost for oil production is cheap, management and maintenance convenient and applied widely.The basic comprising of sucker rod pumping is, lays in advance sleeve pipe in the oil well between ground and oil reservoir, and oil pipe is installed in sleeve pipe again, placing again in oil pipe and passing through the interconnective sucker rod of box cupling.In the process of oil pumping, the eccentric wear phenomenon often occurs between sucker rod and oil pipe, along with the increase of the special construction oil well quantity such as sidetracked hole and deviated directional drilling, the eccentric wear problem seems more general and becomes increasingly conspicuous in the sucker rod pumping industry.Will cause sucker rod to rub when eccentric wear acquires a certain degree or the consequence such as oil pipe is worn out, seriously affect the normal production of oil well and cause the loss of oil pumping yield.When the eccentric wear phenomenon occured, the size of radial pressure that sucker rod bears was the key of the degree of wear, so the production scene is in the urgent need to the device of the deep enough underground survey sucker rod of a kind of energy radial pressure.

Research for eccentric wear problem between sucker rod and oil pipe makes some progress in recent years.As aspect mechanical model research, consider the impact of actual well track, the sucker rod system is subjected to the impact of error and model self error of force of sliding friction and fluid resistance, revise by equivalent viscous drag correction coefficient, make the more accurate (application number: 200810196099.1) of the sucker rod actual loading that calculates; Aspect the research that prevents the eccentric wear technology, 200920246462.6), the pumping rod weighting tube (patent No.: ZL200620077193.1) and Universal eccentric-wear-resistant collar of sucker rod (application number: 201020183938.9) etc., formed some and prevented the effective tool of eccentric wear developed fixing type centralizer for oil pumping rod (application number:.But no matter be mechanical modeling or prevent the eccentric wear technology, all need the down-hole measured path to support and the checking of pressure data, in order to make the assessment of quantification to reducing actual effect that eccentric wear can reach.

About the measurement mechanism of down-hole pressure, delivered some papers or announced some patents.As the development of mechanics somascope load sensor pipe nipple " sucker rod string down-hole " (Liu Songlin etc., the oil instrument, 2007,2:4-7.) literary composition, answer the requirements such as satisfied temperature, pressure, corrosion and scaling, little space and load variations are large although considered pipe nipple, also determined the key technical indexes of load sensor, but what this sensor detected is the combined action result of the multinomial mechanics parameters such as the suffered pulling force of sucker rod, pressure and moment of torsion, and in the time of can't detecting generation eccentric wear phenomenon, sucker rod is subject to the actual numerical value of radial pressure." downhole stored formula rod tube parametric detector " (patent No.: the concrete structure that ZL200420024926.6) has proposed a plurality of parametric detectors, designed sensor storehouse post and circuit board storehouse post two parts are serially connected with between the joint of sucker rod, the parameters such as pressure, torsion, temperature, acceleration and gradient can be detected, but the size of sucker rod radial pressure can't be detected." a kind of pipe column state detection device " (patent No.: ZL200820219679.3) proposed a kind of by down-hole and ground pick-up unit dimerous, realize the integrated measuring of down-hole string temperature, axial force and tubing string slide displacement, but can't detect the concrete numerical value of sucker rod radial pressure.In sum, although existing surveying instrument or detection technique can be measured the different parameters under oil well, but one of most important mechanics parameter when eccentric wear occurs between sucker rod and oil pipe, namely effective measurement mechanism does not still appear in the concrete numerical value of sucker rod radial pressure.

Summary of the invention

The objective of the invention is: propose a kind of can be at the device of underground survey sucker rod radial pressure

Technical solution of the present invention is: a kind of down-hole device for measuring radial pressure of sucker rod, comprise pipe nipple 1, O-ring seal 2, ring bush 3, resistance strain gage 4 and integrated circuit (IC) system 5, and it is characterized in that,

(1) pipe nipple 1 with through hole form, profile is similar to the box cupling of connecting with pumping rod, at the two ends of through hole, one section internal thread is arranged respectively, respectively has a ring groove in the inner end of internal thread, is placed with O-ring seal 2 in groove; The internal thread of pipe nipple 1 is connected with the external thread of sucker rod, after screwing sucker rod, and the top press seal circle 2 of sucker rod and extraneous sealing;

(2) flexible ring bush 3 are close to the through hole inside surface of pipe nipple 1, and the radial pressure that pipe nipple 1 is subject to makes ring bush 3 produce elastic deformations, and for axially drawing of being subject to of pipe nipple 1, pressure and torsion, elastic deformation does not occur ring bush 3;

(3) resistance strain gage 4 is pasted on the inside surface of ring bush 3, and form and detect electric bridges with testing circuit 501 in integrated circuit (IC) system 5, when the elastic deformation of ring bush 3 generations causes that the resistance of resistance strain gage 4 changes, detect electric bridge and produce corresponding Voltage-output signal;

(4) integrated circuit (IC) system 5 is arranged on the inside of pipe nipple 1, and integrated circuit (IC) system 5 comprises testing circuit 501, signal amplification circuit 502, master controller 503, clock circuit 504, mass storage 505, power control circuit 506, high-temperature battery 507 and data communication interface 508.

Advantage of the present invention is:

1, measurement mechanism and sucker rod are put under oil well after screwing, and can replace box cupling work and measure the sucker rod radial pressure.

2, ring bush has played axially drawing of eliminating that sucker rod is subject to, pressure or torsion to the radially effect of pressure detection impact.

3, the key technical indexes is as follows, and the maximum radial pressure of measurement is 500KN; Smallest radial pressure is 10N; Maximum is withstand voltage is 35MPa; Maximum operating temperature is 120 ℃.

Description of drawings

Fig. 1 is the structural representation of device for measuring radial pressure.

Fig. 2 is integrated circuit (IC) system theory diagram of the present invention.

Embodiment

Under regard to the present invention and be described in further details.A kind of down-hole device for measuring radial pressure of sucker rod comprises a pipe nipple 1 with through hole form, referring to Fig. 1, profile is similar to the box cupling of connecting with pumping rod, at the two ends of through hole, one section internal thread is arranged respectively, respectively have a ring groove in the inner end of internal thread, be placed with O-ring seal 2 in groove.The internal thread of pipe nipple 1 is connected with the external thread of sucker rod, after screwing sucker rod, and the top press seal circle 2 of sucker rod and extraneous sealing.A flexible ring bush 3 is close to the through hole inside surface of pipe nipple 1, and resistance strain gage 4 is pasted on the inside surface of ring bush 3.Integrated circuit (IC) system 5 is arranged on the inside of pipe nipple 1, referring to Fig. 2, integrated circuit (IC) system 5 comprises detection electric bridge 501, signal amplification circuit 502, master controller 503, clock circuit 504, mass storage 505, power control circuit 506, high-temperature battery 507 and data communication interface 508.The invention is characterized in,

(1) pipe nipple 1 with through hole form, profile is similar to the box cupling of connecting with pumping rod, at the two ends of through hole, one section internal thread is arranged respectively, respectively has a ring groove in the inner end of internal thread, is placed with O-ring seal 2 in groove.The internal thread of pipe nipple 1 is connected with the external thread of sucker rod, after screwing sucker rod, and the top press seal circle 2 of sucker rod and extraneous sealing.The alloy steel that pipe nipple 1 is selected to have good mechanical properties and heat treatment performance is as material, and its maximum is withstand voltage is 35MPa, and maximum operating temperature is 120 ℃, the maximum radial pressure F that can detect _maxBe 500KN.

(2) flexible ring bush 3 are close to the through hole inside surface of pipe nipple 1, and the radial pressure that pipe nipple 1 is subject to makes ring bush 3 produce elastic deformations, and for axially drawing of being subject to of pipe nipple 1, pressure and torsion, elastic deformation does not occur ring bush 3.Ring bush 3 has played axially drawing of eliminating that sucker rod is subject to, pressure and torsion to the radially effect of pressure detection impact, make pipe nipple 1 drawn vertically, pressure or twisting force and when producing elastic deformation, this deformation can't be delivered to ring bush 3 and the detection of pressure is radially exerted an influence.Ring bush 3 is identical with the material of pipe nipple 1, has identical thermal expansivity in high-temperature oil well.

(3) resistance strain gage 4 is pasted on the inside surface of ring bush 3, and form and detect electric bridges with testing circuit 501 in integrated circuit (IC) system 5, when the elastic deformation of ring bush 3 generations causes that the resistance of resistance strain gage 4 changes, detect electric bridge and produce corresponding Voltage-output signal, the smallest radial pressure that this measurement mechanism can detect is 10N.

(4) integrated circuit (IC) system 5 is arranged on the inside of pipe nipple 1, and integrated circuit (IC) system 5 comprises detection electric bridge 501, signal amplification circuit 502, master controller 503, clock circuit 504, mass storage 505, power control circuit 506, high-temperature battery 507 and data communication interface 508.The output voltage that detects electric bridge is connected with signal amplification circuit 502 by wire, and voltage signal is amplified in the scope that master controller 503 can process.Master controller 503 gathered the primary voltage signal and was converted into corresponding numerical signal every ten seconds, the clock signal that clock circuit 504 produces is passed master controller 503 back, as the timescale data of master controller 503 storages, master controller 503 deposits numerical signal and corresponding timescale data in mass storage 505 in.Power control circuit 506 is connected with high-temperature battery 507 by wire, and data communication interface 508 is used for the exchanges data with host computer, comprises that parameter setting and data derive.

Use the step of apparatus of the present invention to be: at first this contrive equipment will complete on ground the demarcation of radial pressure and the parameter setting of integrated circuit (IC) system before going deep into underground survey.Put under oil well after this measurement mechanism and sucker rod are screwed, can measure the concrete numerical value of sucker rod radial pressure.After the down-hole trips out measurement mechanism, derive by the radial pressure measurement data of data communication interface with storage.

Claims

1. A downhole radial pressure measurement device for sucker rods, including a pup joint [1], a sealing ring [2], an annular bushing [3], a resistance strain gauge [4] and an integrated circuit system [5]. characterized in that,

(1) A nipple [1] in the form of a through hole, which is similar in shape to a coupling connected to a sucker rod. There is a section of internal thread at both ends of the through hole, and an annular groove is opened at the inner end of the internal thread , there is a sealing ring [2] in the groove; the internal thread of the pup joint [1] is connected with the external thread of the sucker rod. seal;

(2) An elastic annular bush [3] is closely attached to the inner surface of the through hole of the short joint [1]. The radial pressure on the short joint [1] causes the elastic deformation of the annular bush [3]. For the short joint [1] Under axial tension, pressure and torsion, the annular bush [3] does not undergo elastic deformation;

(3) The resistance strain gauge [4] is pasted on the inner surface of the annular bush [3], and forms a detection bridge with the detection circuit [501] in the integrated circuit system [5]. When the annular bush [3] generates When the resistance value of the resistance strain gauge [4] changes due to elastic deformation, the detection bridge generates a corresponding voltage output signal;

(4) The integrated circuit system [5] is installed inside the short section [1]. The integrated circuit system [5] includes a detection circuit [501], a signal amplification circuit [502], a main controller [503], a clock circuit [504] ], mass memory [505], power supply control circuit [506], high temperature battery [507] and data communication interface [508].