SU1645468A1 - Method of bottom-hole pumping - Google Patents

Description

one

(21) 4490315/03

(22) 10/06/88

C46J 04/30/91. Bul sixteen

(71) All-Union Petroleum Safety Research Institute

(72) B.A., Kirsch

(53) 622.275.5 (088.8)

(56) Molchanov A.G. and Chicherov V.L. Oilfield “tires and mechanisms. M.- Nedra, 1983, p. 55.

USSR author's certificate V 754038, cl. E 21 B 17/10, 1973.

US patent W 4/141 10, cl. E 21 B 17/10, 166-68, 1987.

(54) METHOD FOR DEPTH-PUMPING OPERATION

(57) The invention relates to the oil industry, in particular to the deep well pumping operation of deep wells. The purpose of the invention is to increase the depth of the downhole

pump rod while reducing hydraulic resistance. The well production is lifted along the production string by a ground-driven well pump rod, centering the sucker rod string in the production string with roller centralizers, as well as lifting the well production along the hollow string of the sucker rod hydraulically in communication with the production string cavity. The distance between the roller centralizers is determined by the mathematical form. During the course of the rod string upwards, its expansion occurs, and during the reverse course - compression. In this case, the centralizers eliminate the bending of the column at critical design points, and the liquid with a lower hydraulic resistance passes through the annular space and along the hollow rods. 6 ill., 1 tab.

(Ls

The invention relates to the oil industry, in particular to the deep well pumping operation of deep wells.

The purpose of the invention is to increase the depth of the downhole sucker rod pump while reducing the hydraulic resistance.

Fig. 1 schematically shows a downhole equipment for carrying out the method; 2 is the same, lower part; on fig.Z - section aa cha figure 1; Fig, 4 - design scheme

sucker rod; Fig. 3 is a layout diagram of centralizers with a conventional rod column; figure 6 - layout of the centralizers on the column of hollow rods when lifting oil along the hollow rods.

The method of downhole pumping includes raising the production of a well along the production string 1 with a well pumping rod 2 with a ground drive 3, centering with roller centralizers 4 columns 5 of pumping rods in the production

S & U & U EE 30

column 1, as well as raising the production of the well through the hollow column 6 of sucker rods by hydraulic communication of the cavity with the cavity exx; xU (L

1-1

Jth

Q PA

thirty

t

dj

35

e E - the modulus of elasticity of the material

rods, kg / m2; I - the moment of inertia of the transverse

rod sections, m, q - weight per meter of rods,

kg / m-, 20

p is the factor of safety,

distance from the bottom of the rod string (or from the well pump) to the next center, m;

experimentally obtained value, equivalent to the weight of the weightless bottom of the rod column, U; well rate, m3 / day, well production density, kg / me;

borehole pump plunger diameter, m;

length of the lower bottom, m, internal diameter of the operational cavity of pipes, m; inner diameter of the column of hollow rods, m,

  the coefficient of hydraulic resistance when the fluid moves between the production casing, the flat bottom, or the column of hollow rods, respectively. Operational column 1 is connected to the cylinder of a submersible pump equipped with a suction clan 7. Plunger 8 enters the cylinder by an injection valve 9. The plunger is connected to a hollow sub 10, the body of which has radial versts 11 for communicating the cavity of the rods 6 to the internal cavity of the operating column 1. Hollow angles 6 are interconnected by fatal centralizers 4 or conventional fta for arranging the column 6 to 40

45

SO

55

of the production column 1, the distance between the roller centralizers 4 being determined from the following ratio, nor:

0

five

0

five

0

five

O

five

with the help of dimensional feet with a specified calculated interval between centralizers.

The centralizer 4 has three grooves at angles of 120 °, with three rollers 12 mounted on the axles 13. The axes 13 are secured with washers 14 and cotter pins 15. The centralizer is hollow with a hole 16 and side slits 17 for connecting the cavity of hollow rods 6 with the cavity of the production string.

The upper centralizer 4 is connected che. a hollow rod with a sub 18 having radial holes 19 is cut. The sub 18 is connected to conventional sucker rods 5. The centralizers 20 and 21 are installed in the conventional rod string version, and the centralizers 22 and 23 are installed in the oil lifting variant only on hollow rods. .

The method is carried out as follows.

As the columns of the hollow rods go upwards, they stretch in one line and the rollers 12 do not touch the walls of the production casing. At the same time, the liquid column above the injection valve 9 inside the hollow rods 6 and inside the production string 1 begins to rise and enters the collection line through the wellhead. During the downward movement, the lower part of the column within the hollow rods 6 will be compressed, but does not lose stability due to its centering, and the upper 5 will be stretched. Moreover, the fluid entering through the discharge valve 9 will be directed upwards, both through the axial holes of the 16 hollow rods 6, centralizers 4, and through the radial holes 11 and 19 into the cavity between the hollow rods 6 and the inner surface of the production string 1. The rollers 12 when by this

51645463

will: roll over on their axes 13 along the inner surface of the production casing 1. The liquid will

pass through the centralizer through grooves 17, placed at an angle of 120 ° with honey rollers 12. In the case of work in sand wells, when it is necessary to increase the fluid lifting speed to prevent sand settling, centralizers 22 and 23 are performed without radial holes, and hollow rods continue to wells (Fig. 6).

Example. To determine the location of the centralizers, we will take the column of hollow rods DM 0.048 m. The flow rate of the well Q is 30 m3 / day, d is 0.102 m, d is 0.04 m. The modulus of elasticity is E 2,16 kg / cm2 2.1 "x 1 10 kg / m2. The moment of inertia I 0.05 - (0.048 - 0.044) 1.36 to m.

The linear weight of the column of hollow rods together with the coupling q is 4.45 kg / m (we assume that the weight of the coupling is approximately equal to the weight of the centralizer).

The safety factor n 1.2. Length of fitted bottom for weight 250 kg, L 20 m. Length of hollow rods for weight 250 kg

1 25 ° 1 4/5

56 m.

After substitution and solution we get

 0 + 3.14

L

ten

li 36-10 7

4.45 -1.2 (56-0)

72L22

AJsT1

9.6 m,

n L 72.22 9.6 + --Ј,

,four

72 22 20.2 + l | 36, 8

 20.2 m,

 32.2

x-

+ B

10nq

E I

- module of elasticity of the material of the rods, kg / m2;

- the moment of inertia of the cross section of the rods,

q - dog running meter rods, kg / m;

+

6

72.22

2 M, 8

46.8 m

The remaining length C 56-46.8 9.2 is calculated as a rod loaded under its own weight with one hinged and other free ends using the formula

2E1

Where

Im

2,

then R.

Zl142- 2 ± 1 -10 Z36

 86 kg

weight of the same length

9.2 4.45 40.9 kg

which is significantly less than P, so we don’t install more centralizers. In a similar way, some other combinations of parameters of the downhole pumping unit can be determined, which are tabulated.

Claims (1)

Invention Formula The method of deep-well pumping, including raising the production of a well through the production string by a ground-driven well pump rod pump and centering the rod of pump rods in the production column, characterized in that, in order to increase the depth of the well pump rod while reducing hydraulic resistance the lifting of the well production is carried out along the hollow string of sucker rods by hydraulically communicating the cavity of the latter with the cavity of the production string, 4S than distance x between centralizers determined from the following relationship: about . V l (di-di) () , 0q - 21P-5kJk  Uq 4,5-IOffl d 1h n - factor of safety; - distance from the bottom of the rod string (or from the well pump) to the next centralizer, M { gi - experimentally obtained value, equivalent to the weight of the weightless bottom of the rod column, H; Q - well flow rate, m3 / day, And - well production density, kg / m1, „and - diameter of the well plunger pump, m; LJ - length of the desired bottom, m; .HcU- internal diameters of the production string of pipes and columns of hollow rods, respectively Calculated data on the placement of roller centrels in parts of a column of hollow rods 494056 484067 484040 603090 , m;  Xp is the coefficient of hydraulic resistance when fluid flows in the annular space between the operating column, and the lower low 1,  Ac is the hydraulic drag coefficient for fluid flow in the annular space between the production string and hollow rods. 9,620,232,216,8 919,629,241,215,8 7,615,6243342.6 53, 65.2 10,521,5375270 0Y 89V5V91 FIG. five FIG. B