RU112291U1 - Borehole Protector - Google Patents

Abstract

Borehole protector containing a body, an electrode made of magnesium alloy, insulators and couplings, characterized in that the protector body with an electrode concentrically located inside it, filled with an electrolyte, for example, a 10% NaCl solution, is screwed with a perforated pipe located in it the upper part, the lower part of the device is screwed into the sludge collection branch pipe, closed with a threaded plug, the well protector itself is installed below the filter.

Description

The utility model relates to borehole pumps designed for pumping high-water cut, mineralized, and viscous fluids from oil wells — conditions that cause intense corrosion of oilfield equipment, as well as conditions that cause salt and paraffin deposition of underground oilfield equipment.

A well-known sucker-rod pump for pumping highly viscous fluids from wells (Oilfield equipment; Handbook / Ed. By E.I. Bukhalenko. - 2nd ed., Revised and additional - M .; Nedra, 1990. - 559 p .; silt .(one).

When the plunger moves down in the area of the cylinders enclosed between the plungers, a vacuum is created, due to which the lower valve of the valve unit opens and the formation fluid enters the said zone. Closed at the same time, the upper valve of the valve block unit perceives the pressure of the liquid column and creates an additional downward load, which helps to overcome the hydraulic resistance in the pump and the friction forces of the rod string against the pumped out high-viscosity fluid. The latter is very significant, since it eliminates the hang of the rods due to excessive friction.

A disadvantage of the known device is the inability to use a device for pumping fluids from wells with high water cut, high salinity, the presence of a significant amount of abrasive substances, both at the bottom of the wells and washed out of the formation — factors contributing to the corrosion wear of oilfield equipment, including tubing tubing ), sucker rods and borehole pump, due to electrochemical processes that cause its corrosion.

The closest in technical essence and purpose to the alleged invention is Well Protector No. 92486. - 20091398234/22. Claim 10/07/2010; Publ. 03/20/2010. Bull. No. 8. (2)

The protector provides cathodic polarization of the inner surface of the underground part of oilfield equipment and is located between the suction valve of the sucker rod pump and the filter, and consisting of a housing, an electrode made of magnesium alloy, perforated insulators - lower and upper, connecting pipes and couplings.

The disadvantage of the design of the pump equipped with this device is; significant abrasive wear of the magnesium tread by mechanical impurities (sand) in the fluid to be lifted and the possibility of tread wear products getting into the flow part of the pump if chemically active reagents are used (acid treatments of the bottom-hole formation zone).

The purpose of the utility model is to increase the efficiency of a borehole sucker rod pump in complicated geological and technical conditions, that is, to reduce the negative impact of chemical (carbon dioxide and hydrogen sulfide) corrosion, salt and paraffin deposits without additional wear of the magnesium electrode.

This goal is achieved in that the borehole tread comprising a housing, an electrode made of magnesium alloy, insulators, and couplings, the tread housing with an electrode concentrically located inside it, is filled with an electrolyte, for example, a 10% NaCl solution, screwed with a perforated nozzle located in it the upper part, the lower part of the device is screwed into the slurry collecting pipe, which is closed by a threaded plug; the downhole protector itself is installed below the filter.

The proposed design eliminates the negative impact of aggressive corrosive medium on the electrode and eliminates the accumulation of salts and paraffin hydrate deposits in the flow part of the pump

In FIG. schematic depicts a downhole protector.

Downhole protector contains; perforated nozzle - pos. 1, blind coupling - pos. 3, case - pos. 4, insulators - pos. 5, electrode - pos. 6, sludge collecting nozzle - pos. 7, plug - pos. 8. The free space of the casing - pos.4, before the tread into the well is filled with electrolyte.

Downhole tread works as follows.

After installing the protector of the wellbore below the sucker rod pump (SHG) filter, the flow of lift fluid into the pump is provided through the perforated pipe pos.1 through the filter (not shown) in the pump, excluding the passage through the active zone of the tread device, protecting it from mechanical wear. Formed chemical current source Fe-Mg, a 10% NaCl solution is used as an electrolyte, which will provide protective protection for pumping equipment, and simultaneously, due to secondary electrochemical reactions on metal surfaces of the casing - item 4 and metal pumping equipment, including casing, gas bubbles will form, preventing the formation of paraffin hydrate deposits on the walls of the pump casing and pipes, contributing to their separation. Insoluble compounds, due to secondary chemical reactions, will be removed from the protective housing - item 4 through the holes of the lower insulator - item 5. In turn, the viscous friction of the elevated flow is reduced and a gas-liquid medium is created with a density of lower liquid density in the annulus. By changing the geometric dimensions of the electrode (diameter and length), the efficiency of the cleaning processes and the prevention of corrosion and corrosion deposits on the surfaces of the pump and pipes are regulated.

Information sources:

1. Oilfield equipment; Handbook / Ed. E.I. Bukhalenko. - 2nd ed., Revised. and add. - M .; Nedra, 1990 .-- 559 p .; silt.

2. RF patent No. 92486. Downhole tread - 20091398234/22. Claim 10/07/2010; Publ. 03/20/2010. Bull. No. 8.

Claims (1)

Downhole protector containing a housing, an electrode made of magnesium alloy, insulators and couplings, characterized in that the tread housing with an electrode concentrically located inside it, filled with an electrolyte, for example, 10% NaCl solution, is screwed with a perforated nozzle located in it the upper part, the lower part of the device is screwed into the slurry collecting pipe, which is closed by a threaded plug; the downhole protector itself is installed below the filter.