CN105510222A - Dynamic friction coefficient measuring device of drilling fluid mud cake and method thereof - Google Patents

Abstract

The invention relates to a dynamic fiction coefficient measuring device of drilling fluid mud cake and a method thereof. According to the measuring device, leveling bolts are arranged on a base plate of an L-shaped support; a movable support plate is hinged to the perpendicular included angle of the L-shaped support, and the other end of the movable support plate is hinged to a slide plate; the slide plate is connected slantwise between the base plate and a vertical plate of the L-shaped support; an upper fixed plate and a lower fixed plate are vertically fixed on the upper inclined surface of the slide plate; the spacing between the upper and lower fixed plates is equal to diameter of the measured drilling fluid mud cake; an independent disk-shaped slide block is arranged between the upper fixed plate and the lower fixed plate; diameter of the disk-shaped slide block is far less than diameter of the measured drilling fluid mud cake; and a timing device for sliding time of the disk-shaped slide block is also mounted between the upper fixed plate and the lower fixed plate. According to the measuring method, by measuring inclination angle between the slide plate and the base plate, distance between the upper and lower fixed plates is measured, and time of the disk-shaped slide block falling to the lower fixed plate is recorded; and finally, dynamic fiction coefficient of the mud cake is calculated. The device and the method are simple and convenient to operate, and measuring results are more accurate.

Description

A kind of drilling fluid mud cake dynamic friction coefficient measuring device and method

Technical field

The present invention relates to property of drilling fluid field of measuring technique, particularly a kind of measurement mechanism of appraisal drilling liquid mud cake kinetic friction coefficient and method.

Background technology

Along with the development of oil drilling technology, extended reach well, horizontal well get more and more, also more and more higher to the requirement of drilling fluid lubricating performance, and the lubricity of drilling fluid plays vital effect to safe construction.

At present domestic and international for drilling fluid mud cake lubricity or Study on Friction Coefficient less, rarely have article to report some new instruments evaluating mud cake lubricities or new method.The instrument of laboratory evaluation mud cake greasy property or friction factor has slide block type filter cake stuck factor analyzer, this instrumentation is simple, but also come with some shortcomings part: the friction factor measured by (1) is the friction factor that slide block starts maximum static friction force generation when gliding, can not actual response dynamic friction coefficient, maximum static friction force is larger than kinetic force of friction; (2) owing to starting slide plate corner when gliding with eye-observation slide block, some lags behind real reading unavoidably, causes bigger error.Therefore, be necessary to develop the measurement mechanism that a kind of measuring accuracy is high, can evaluate mud cake dynamic friction coefficient.

Summary of the invention

The object of this invention is to provide a kind of measurement mechanism of mud cake kinetic friction coefficient, this device is simple to operate, measurement data is accurate, can the dynamic friction coefficient size of accurate response drilling fluid mud cake.

In order to solve the problem, technical scheme of the present invention is:

Drilling fluid mud cake dynamic friction coefficient measuring device, the base plate of L bracket 1 is provided with levelling bolt 8, at the vertical angle place articulate support plate 3 of L bracket, the other end hinge slide plate 2 of movable supporting board 3, between the base plate that slide plate 2 tilts to be overlapped on L bracket 1 and riser, upper mounted plate 4 and bottom plate 5 is vertically fixed with at slide plate 2 ramp, spacing between upper bottom plate is identical with tested drilling fluid mud cake diameter, independently plectane slide block 11 is set between upper mounted plate 4 and bottom plate 5, the diameter of plectane slide block 11 is much smaller than the diameter of tested drilling fluid mud cake, the time set of plectane slide block 11 coasting time is also provided with between upper mounted plate 4 and bottom plate 5.

Such scheme also comprises:

Described time set arranges conductive contact respectively on upper mounted plate 4 and bottom plate 5 opposite face, and conductive contact is connected with timer 7 by wire 6, and upper mounted plate 4 and bottom plate 5 are set to electric conductor and are connected with timer 7 respectively simultaneously.

Described time set arranges conductive contact respectively on upper mounted plate 4 and bottom plate 5 opposite face, and conductive contact is connected with timer 7 by wire 6, and plectane slide block 11 is set to electric conductor and is connected with timer 7 respectively simultaneously.

At L bracket 1 angle set amount hornwork 9, protractor 9 and movable supporting board 3 are connected by tightening screw 10; The base plate of L bracket 1 is provided with level meter, described level meter circle spirit bubble or straight surveyor's staff.

Measuring method according to aforesaid drilling fluid mud cake dynamic friction coefficient measuring device: the base plate first adjusting L bracket 1 is level, measure the inclination angle between slide plate 2 and base plate and be designated as α, the drilling fluid mud cake produced by filtration device is fixed on slide plate, and two ends are fixed by upper bottom plate; Distance in measurement between bottom plate 4,5 is also designated as L; Be m by known quality again, diameter is that the plectane slide block 11 of d is placed on mud cake upper end, record round slider is in the time dropping down onto bottom plate and be designated as t; Last according to L=a*t ²/ 2, and G*sin α-F=m*a, calculate friction force F, then according to K _f=F/G*cos α calculates the kinetic friction coefficient K of mud cake _f.

The calculation procedure of the measuring method of described drilling fluid mud cake dynamic friction coefficient measuring device:

According to Acceleration Formula:

$L-d=\frac{1}{2}{\mathrm{at}}^2---\left(1\right)$

:

$a=\frac{2(L-d)}{t^2}---\left(2\right)$

According to the relation between power and acceleration:

Gsinα-F＝ma(3)

Bring formula (2) into above formula (3), draw friction force F:

$F=G\sin \mathrm{\α}-\frac{2m(L-d)}{t^2}---\left(4\right)$

Therefore, kinetic friction coefficient K _ffor:

$K_f=\frac{F}{G\cos \mathrm{\α}}=\frac{G\sin \mathrm{\α}-\frac{2m(L-d)}{t^2}}{G\cos \mathrm{\α}}=\tan \mathrm{\α}-\frac{2(L-d)}{{\mathrm{gt}}^2\cos \mathrm{\α}}---\left(5\right)$

Compared with prior art, the present invention is simple to operation, utilize mechanics principle to calculate the kinetic friction coefficient of mud cake, and can arbitrarily adjust slide plate inclination angle, repeat experiment, automatic data collection, measurement result is more accurate, and the present invention can be widely used in the department such as laboratory in one's power of situ of drilling well, Research Center.

Accompanying drawing explanation

Fig. 1 is the structure diagram of an embodiment of the present invention.

In figure, 1, support, 2, slide plate, 3, movable supporting board, 4, upper mounted plate, 5, bottom plate, 6, connecting line, 7, timer, 8, levelling bolt, 9, protractor, 10, tightening screw.

Fig. 2 is the structure diagram of involved plectane slide block in this measurement mechanism.

Fig. 3 is the partial enlarged drawing of this measurement mechanism.

Embodiment

Below in conjunction with accompanying drawing, the present invention is described in further detail.

Shown in composition graphs 1, the drilling fluid mud cake dynamic friction coefficient measuring device of the embodiment of the present invention forms primarily of support 1, slide plate 2, movable supporting board 3, upper mounted plate 4, bottom plate 5, connecting line 6, timer 7, levelling bolt 8, protractor 9, tightening screw 10 and plectane slide block Fig. 2.

Its medium-height trestle 1 is L shape metal support, and bottom is provided with levelling bolt 8 and circle spirit bubble, is used for regulating the level of whole device; Movable supporting board 3 one end is connected with the stationary shaft on slide plate 2, and one end is connected with the axis of L bracket 1, and can rotate about the axis, and is screwed by tightening screw 10 after determining angle, thus controls the inclination angle size of slide plate 2; Upper mounted plate 4 and bottom plate 5 are installed on slide plate, mainly play fixing mud cake, and the distance between upper bottom plate are fixing, equal with formation mud cake diameter; Timer 7 is connected with bottom plate 5 with upper mounted plate 4 respectively by two connecting lines 6, and tie point is contact contact, and contact contact is contact induction self-clocking; Plectane slide block is circular flat panel metal block, electroplating surface polishing.When plectane slide block separates with the contact contact of upper mounted plate 4, timer 7 starts timing, and when plectane slide block starts the contact contact encountering bottom plate 5, timer 7 stops timing.

Utilize the measuring method of said apparatus:

First adjust levelling bolt, make the bubble in circle spirit bubble be in center; Adjusting movable supporting board again makes slide plate be in a fixing inclination alpha, and the mud cake produced by filtration device is fixed on slide plate, and two ends are fixed by upper bottom plate; Distance between upper bottom plate is L; Be m by known quality again, diameter is that the plectane slide block of d is placed on mud cake upper end, and contact contact with upper mounted plate and contact; Now unclamping hand makes slide block start to glide under the effect of partical gravity, and simultaneously timer starts timing, and when slide block drops down onto bottom plate contact contact, timer stops timing, now records timer periods t; Last according to L=a*t ²/ 2, and G*sin α-F=m*a, calculate friction force F, then according to K _f=F/ (G*cos α) calculates the kinetic friction coefficient K of mud cake _f.

Calculation procedure:

According to Acceleration Formula:

$L-d=\frac{1}{2}{\mathrm{at}}^2---\left(1\right)$

:

$a=\frac{2(L-d)}{t^2}---\left(2\right)$

According to the relation between power and acceleration:

Gsinα-F＝ma(3)

Bring formula (2) into above formula (3), draw friction force F:

$F=G\sin \mathrm{\α}-\frac{2m(L-d)}{t^2}---\left(4\right)$

Therefore, kinetic friction coefficient K _ffor:

$K_f=\frac{F}{G\cos \mathrm{\α}}=\frac{G\sin \mathrm{\α}-\frac{2m(L-d)}{t^2}}{G\cos \mathrm{\α}}=\tan \mathrm{\α}-\frac{2(L-d)}{{\mathrm{gt}}^2\cos \mathrm{\α}}---\left(5\right)$

Claims (6)

1. drilling fluid mud cake dynamic friction coefficient measuring device, it is characterized in that: on the base plate of L bracket (1), be provided with levelling bolt (8), at vertical angle place articulate support plate (3) of L bracket, the other end hinge slide plate (2) of movable supporting board (3), between the base plate that slide plate (2) tilts to be overlapped on L bracket (1) and riser, upper mounted plate (4) and bottom plate (5) is fixed with at slide plate (2) ramp, spacing between upper bottom plate is identical with tested drilling fluid mud cake diameter, independently plectane slide block (11) is set between upper mounted plate (4) and bottom plate (5), the diameter of plectane slide block (11) is much smaller than the diameter of tested drilling fluid mud cake, the time set of plectane slide block (11) coasting time is also provided with between upper mounted plate (4) and bottom plate (5).

2. drilling fluid mud cake dynamic friction coefficient measuring device according to claim 1, it is characterized in that: described time set arranges conductive contact respectively on upper mounted plate (4) and bottom plate (5) opposite face, conductive contact is connected with timer (7) by wire (6), and upper mounted plate (4) and bottom plate (5) are set to electric conductor and are connected with timer (7) respectively simultaneously.

3. drilling fluid mud cake dynamic friction coefficient measuring device according to claim 1, it is characterized in that: described time set arranges conductive contact respectively on upper mounted plate (4) and bottom plate (5) opposite face, conductive contact is connected with timer (7) by wire (6), and plectane slide block (11) is set to electric conductor and is connected with timer (7) respectively simultaneously.

4. the drilling fluid mud cake dynamic friction coefficient measuring device according to claim 1 or 2,3, it is characterized in that: in L bracket (1) angle set amount hornwork (9), protractor (9) and movable supporting board (3) are connected by tightening screw (10); The base plate of L bracket (1) is provided with level meter, described level meter circle spirit bubble or straight surveyor's staff.

5. according to the measuring method of drilling fluid mud cake dynamic friction coefficient measuring device according to claim 4, it is characterized in that: the base plate first adjusting L bracket (1) is level, measure the inclination angle between slide plate (2) and base plate and be designated as α, the drilling fluid mud cake produced by filtration device is fixed on slide plate, and two ends are fixed by upper bottom plate; Distance in measurement between bottom plate (4,5) is also designated as L; Be m by known quality again, diameter is that the plectane slide block (11) of d is placed on mud cake upper end, record round slider is in the time dropping down onto bottom plate and be designated as t; Last according to L=a*t ²/ 2, and G*sin α-F=m*a, calculate friction force F, then according to K _f=F/ (G*cos α) calculates the kinetic friction coefficient K of mud cake _f.

6. the measuring method of drilling fluid mud cake dynamic friction coefficient measuring device according to claim 5, is characterized in that calculation procedure:

According to Acceleration Formula:

$L-d=\frac{1}{2}{\mathrm{at}}^2---\left(1\right)$

:

$a=\frac{2(L-d)}{t^2}---\left(2\right)$

According to the relation between power and acceleration:

Gsinα-F＝ma(3)

Bring formula (2) into above formula (3), draw friction force F:

$F=G\sin \mathrm{\α}-\frac{2m(L-d)}{t^2}---\left(4\right)$

Therefore, kinetic friction coefficient K _ffor:

$K_f=\frac{F}{G\cos \mathrm{\α}}=\frac{G\sin \mathrm{\α}-\frac{2m(L-d)}{t^2}}{G\cos \mathrm{\α}}=\tan \mathrm{\α}-\frac{2(L-d)}{{\mathrm{gt}}^2\cos \mathrm{\α}}---\left(5\right)$