RU85194U1 - DRILL RIG ELECTRICAL SEPARATOR - Google Patents

Abstract

Drill string electric separator, including metal sub, connected by tapered thread through a dielectric gasket, a sheath of waterproof dielectric material mounted on annular elastic seals inside the separator in the joint area of the sub, and an outer coating of dielectric material, characterized in that the gap between the inner shell and metal sub filled with mineral oil or mineral grease.

Description

The utility model relates to the field of geophysical research of wells and is intended for use as part of cableless telemetry systems as an antenna to provide two-way communication between the telesystem and ground equipment.

Known electrical separator, including upper and lower sub, connected by a tapered thread, between the profiles of which an insulating gasket is installed. Inside and outside the sub are insulated with layers of structural fiberglass. The insulating layers can be made in the form of fiberglass pipes, one of which is inserted inside the electrical separator, and the other is put on the separator (USSR copyright certificate No. 994704, MKI 3 Е21В 47/02, Е21В 17/00, decl. 12/31/1980 )

Fiberglass used as a dielectric coating has significant porosity and high moisture absorption capacity. The saturation of the fiberglass shell with a drilling fluid leads to a decrease in its dielectric properties.

The closest in technical essence is the design of the electrical separator, including metal sub, assembled in a single conical threaded connection with a gasket of dielectric material between the profiles of the connecting threads, according to the patent for utility model No. 47970, IPC 7 Е21В 47/00, stated. 05/03/2005 The joint zone of the sub is externally covered with a polymer composite material (fiberglass). A sheath made of waterproof dielectric material (fluoroplastic) is installed inside the electrical separator in the joint zone of the sub on elastic ring seals.

The disadvantage of this design is the possibility of penetration of the drilling fluid under the inner shell as a result of damage (for example, aging) of the elastic ring seals. In this case, the flushing fluid under pressure will fill the gaps and voids under the shell, and the design will no longer fulfill its purpose: it will not provide electrical disconnection of the upper and lower parts of the drill string due to the flow of current between the sub on the drilling fluid under the inner shell.

The technical task of the utility model is to increase the reliability of the electrical separator.

The solution to this problem has been achieved by the fact that in an electric splitter, including metal sub, connected by a tapered thread through a dielectric gasket, a shell of waterproof dielectric material mounted on annular elastic seals inside the separator in the joint area of the sub, and an outer coating of dielectric material, the gap between the inner shell and metal sub is filled with mineral oil or mineral grease.

Figure 1 shows the design of the proposed electrical separator.

The electric separator contains metal sub 1 and 2 connected by a tapered thread through a dielectric gasket 3. Inside the separator in the joint zone of the sub on the O-rings 4 of elastic material, a sheath 5 of waterproof dielectric material is installed. An opening 6 is made in one of the sub, designed to fill the gaps and voids between the shell 5 and the sub with mineral oil. Upon completion of the operation of filling with oil, the hole is closed with a plug 7. On the outside, the junction zone of the sub is closed by a layer of dielectric material 8.

As the material for the manufacture of the inner shell, polyethylene, caprolon, polyamide, fluoroplastic, etc. can be used.

An electrical splitter is made as follows.

A gasket 3 of dielectric material is placed on the surface of the conical thread of the nipple sub 2. Collapse sub. On the inner side of the separator on the annular seals 4 establish a shell 5, for example of fluoroplastic. Through the hole 6, the space 9 between the shell 5 and the metal sub is evacuated and filled with mineral oil. Close the hole with the plug 7. The plug 7 can be installed by welding or threaded connection on the ring elastic seals. From the outside, the junction zone of the sub is closed with a layer of dielectric material 8, for example, a fiberglass tape impregnated with a binder is wound, and polymerization is carried out.

Instead of mineral oil, a mineral lubricant such as CIATIM can be used. In this case, grease is applied to the outer surface of the inner shell before installation.

Thus, the joint of the sub on the inside is closed by a sheath of waterproof dielectric material, the space under which is filled with mineral oil (or grease), which prevents the penetration of the drilling fluid under the sheath in case of damage to the elastic rings.

Using the proposed design can improve the reliability of the electric separator by preventing the possibility of its "breakdown" from the inside as a result of the penetration of the drilling fluid under the dielectric sheath of a waterproof material.

Claims (1)

Drill string electric separator, including metal sub, connected by tapered thread through a dielectric gasket, a sheath of waterproof dielectric material mounted on annular elastic seals inside the separator in the joint zone of the sub, and an outer coating of dielectric material, characterized in that the gap between the inner shell and metal sub filled with mineral oil or mineral grease.