Novel ultrahigh-temperature hard electrode nipple

Abstract

The invention discloses a novel ultra-high temperature hard electrode short section which comprises an instrument main body, two centralizing rings, a sealing ring, a compensation ring, a plurality of sections of first insulating rings and a section of second insulating ring are arranged on the outer wall of the instrument main body in a sleeving mode, two centralizing rings are located at the two ends of the instrument main body respectively, and one centralizing ring is adjacent to the sealing ring; one centralizing ring is adjacent to the first insulating ring, the other centralizing ring is adjacent to the compensation ring, the compensation ring is adjacent to the second insulating ring, a plurality of sections of first insulating rings are arranged between the second insulating ring and the sealing ring, the adjacent first insulating rings and the first insulating ring and the second insulating ring are overlapped and matched, and sealing rings are arranged at the overlapped positions. According to the novel ultra-high-temperature hard electrode short section, the sealing ring, the first insulating ring and the second insulating ring are of an assembly type structure to form the insulating part, a glass fiber reinforced plastic winding process is replaced, the insulating reliability is high, the insulating part can be detached, maintained and replaced, and field operation is convenient.

Description

Technical Field

[0001] The invention belongs to the field of petroleum well logging, and in particular relates to a novel ultra-high temperature hard electrode nipple in the field. Background Art

[0002] With the improvement of exploration and drilling technology, the drilling depth is getting deeper and deeper, and the number of wells with a depth of 10,000 meters has also increased in recent years. According to the relationship between well temperature, well depth and geothermal gradient, the deeper the well, the higher the well temperature. The deep and shallow lateral curves are conventional curves of resistivity logging, which play an important role in formation evaluation. The deep lateral curve requires the use of the hard electrode electric field shielding length to complete the curve measurement due to the detection depth requirements. The insulation of the hard electrode and the high temperature resistance of the insulating material have an important influence on the quality of the deep lateral curve. The hard electrode pup joints in the existing technology mostly adopt the fiberglass winding process. Under high temperature conditions, the solidified resin of the fiberglass material softens, the strength decreases, and the wear resistance deteriorates. When encountering an acidic or alkaline mud environment, the fiberglass is prone to delamination and disintegration, and the insulation reliability is reduced, which affects the measurement of the deep lateral curve; and the fiberglass insulating material adopts the winding process and is processed as a whole, and cannot be replaced on site. Summary of the invention

[0003] The technical problem to be solved by the present invention is to provide a new type of ultra-high temperature hard electrode short section, which is used for deep lateral curve measurement under ultra-high temperature environment conditions of 230°C. The upper and lower ends of the hard electrode have an insulating function, and the outer surface is covered with high temperature resistant non-metallic insulating material to shield the electric field and meet the distance requirements of the deep lateral measurement loop electrode. It has the characteristics of high temperature resistance, high temperature compensation of insulating material, high insulation reliability, and repairable and replaceable insulating material.

[0004] The present invention adopts the following technical solution: A novel ultra-high temperature hard electrode short section, the improvement of which lies in: comprising an instrument body, two straightening rings, a sealing ring, a compensating ring, several sections of first insulating rings and one section of second insulating ring are sleeved on the outer wall of the instrument body, wherein the two straightening rings are respectively located at the two ends of the instrument body, one straightening ring is adjacent to the sealing ring, the other straightening ring is adjacent to the compensating ring, the compensating ring is adjacent to the second insulating ring, several sections of first insulating rings are arranged between the second insulating ring and the sealing ring, adjacent first insulating rings and first insulating rings and second insulating rings are overlapped and matched, and sealing rings are installed at the overlapping parts.

[0005] Furthermore, an upper cover cap and a lower cover cap are respectively installed on the instrument interfaces at both ends of the instrument body.

[0006] Furthermore, the straightening ring is fixed to the hook hole of the instrument body with screws.

[0007] Furthermore, the righting ring is made of martensitic stainless steel.

[0008] Furthermore, more than two rows of hard alloy blocks are embedded in the circumferential direction on the straightening ring.

[0009] Furthermore, each row has 6 cemented carbide blocks, and the 6 cemented carbide blocks in each row are evenly distributed along the circumferential direction.

[0010] Furthermore, the sealing ring, the first insulating ring and the second insulating ring are all made of glass fiber reinforced PEEK material.

[0011] Furthermore, the compensation ring is a metal grooved tube.

[0012] The beneficial effects of the present invention are: The new type of ultra-high temperature hard electrode short section disclosed in the present invention is composed of a sealing ring, a first insulating ring and a second insulating ring, which adopt an assembled structure to form an insulating part, replacing the winding glass fiber reinforced plastic process, with high insulation reliability. The insulating part can be disassembled, repaired and replaced, which is convenient for on-site operation. The adjacent first insulating rings and the first insulating ring and the second insulating ring overlap and cooperate, and a sealing ring is installed at the overlap to prevent mud from entering the overlap, thereby ensuring the insulation integrity between the multiple insulating rings and meeting the electric field insulation shielding requirements. The sealing ring, the first insulating ring and the second insulating ring are all made of glass fiber reinforced PEEK material, which can work for a long time under an environmental condition of 260°C, solving the problem of high temperature resistance of the insulating material. An elastic compensation ring is set to compensate for the length change of the insulating material under high temperature conditions, solving the problem of high temperature expansion compensation of the insulating material. Straightening rings are installed at both ends of the instrument body to prevent the insulating part from colliding and rubbing with the well wall, thereby improving the wear resistance of the instrument body. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a schematic diagram of the composition of the novel ultra-high temperature hard electrode short section disclosed in the present invention; Figure 2 It is a schematic diagram of the composition of the insulating part of the novel ultra-high temperature hard electrode short section disclosed in the present invention; Figure 3 It is a structural schematic diagram of the straightening ring in the novel ultra-high temperature hard electrode short section disclosed in the present invention; Figure 4 It is a schematic diagram of the axial section of the straightening ring in the novel ultra-high temperature hard electrode short section disclosed in the present invention.

[0014] Reference numerals: 1—upper cover cap, 2—rightening ring, 21—hard alloy block, 3—sealing ring, 4—first insulating ring, 5—second insulating ring, 6—compensation ring, 7—instrument body, 8—upper cover cap, 9—sealing ring. DETAILED DESCRIPTION

[0015] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0016] Example 1: This example discloses a new type of ultra-high temperature hard electrode short section, which has high insulation reliability under high temperature conditions and meets the requirements of long-term use (at least 30 hours) at 230°C and short-term use (at least 6 hours) at 260°C. Figure 1 As shown, it includes an instrument body 7, on the outer wall of which are sleeved two straightening rings 2, a sealing ring 3, a compensating ring 6, a plurality of first insulating rings 4 and a second insulating ring 5, wherein the two straightening rings are respectively located at both ends of the instrument body, one straightening ring is adjacent to the sealing ring, the other straightening ring is adjacent to the compensating ring, and the compensating ring is adjacent to the second insulating ring, as shown in FIG. Figure 2 As shown, there are several sections of first insulating rings between the second insulating ring and the sealing ring. Adjacent first insulating rings and first insulating rings and second insulating rings overlap and fit, and a sealing ring 9 is installed at the overlapping position. This multi-section combination makes it easy to replace the insulating rings. The length of the multi-section first insulating ring and the second insulating ring is relatively long after being combined. The expansion coefficient of the non-metallic material is much greater than that of the metal instrument body. The length will change greatly at high temperature. To compensate for this length change, a compensation ring is installed between the second insulating ring and the straightening ring. The compensation ring adopts an elastic metal grooved tube. When the force is applied, the groove will produce elastic deformation to avoid permanent deformation of the insulating ring due to high temperature expansion.

[0017] In this embodiment, an upper cover cap 1 and a lower cover cap 8 are respectively installed on the instrument interfaces at both ends of the instrument body, which can not only protect the instrument interfaces but also be used when hoisting the instrument and carrying it daily.

[0018] The insulating part composed of the sealing ring, the first insulating ring and the second insulating ring is made of glass fiber reinforced PEEK GF30 material to achieve electric field insulation shielding, and the sealing ring is sealed inside to isolate the metal at the upper and lower ends. PEEK material is dense, has low water absorption, isotropic, has good acid and alkali resistance, can work stably under 260℃ environment conditions, and can meet the use requirements under ultra-high temperature conditions.

[0019] Use screws to fix the righting ring to the hook hole of the instrument body. The righting ring is replaceable. The righting ring isolates the insulating part from the well wall by a certain distance to avoid the insulating part from colliding and wearing with the well wall during logging, reducing the risk of damage to the insulating part and improving the reliability of field applications. In order to improve the wear resistance of the righting ring, the righting ring is made of martensitic stainless steel 05Cr17Ni4Cu4Nb. Through solid solution + aging treatment, the hardness of the material is controlled between HRC35-38. Under this hardness condition, the material has both certain strength and hardness, and certain toughness, which is conducive to improving wear resistance. Figure 3 As shown in FIG. 4 , two rows of cemented carbide blocks 21 are embedded in the circumferential direction on the centralizing ring. Each row has 6 cemented carbide blocks, and the 6 cemented carbide blocks in each row are evenly distributed along the circumferential direction. When the centralizing ring contacts and rubs against the well wall, the cemented carbide blocks greatly improve the wear resistance of the centralizing ring, reducing its replacement frequency and application cost.

Claims

1. A new type of ultra-high temperature hard electrode short section, characterized by: The invention comprises an instrument body, on the outer wall of which are sleeved two straightening rings, a sealing ring, a compensating ring, several sections of first insulating rings and one section of second insulating ring, wherein the two straightening rings are respectively located at the two ends of the instrument body, one straightening ring is adjacent to the sealing ring, the other straightening ring is adjacent to the compensating ring, the compensating ring is adjacent to the second insulating ring, several sections of first insulating rings are arranged between the second insulating ring and the sealing ring, adjacent first insulating rings and first insulating rings and second insulating rings are overlapped and matched, and sealing rings are installed at the overlapping parts.

2. According to claim 1, the novel ultra-high temperature hard electrode nipple is characterized by: An upper cover cap and a lower cover cap are respectively installed on the instrument interfaces at both ends of the instrument body.

3. According to claim 1, the novel ultra-high temperature hard electrode nipple is characterized by: Fix the straightening ring to the hook hole of the instrument body with screws.

4. According to claim 1, the novel ultra-high temperature hard electrode nipple is characterized by: The righting ring is made of martensitic stainless steel.

5. According to claim 1, the novel ultra-high temperature hard electrode nipple is characterized by: More than two rows of hard alloy blocks are embedded in the circumferential direction on the straightening ring.

6. According to claim 5, the novel ultra-high temperature hard electrode nipple is characterized in that: There are 6 cemented carbide blocks in each row, and the 6 cemented carbide blocks in each row are evenly distributed along the circumferential direction.

7. According to claim 1, the novel ultra-high temperature hard electrode nipple is characterized by: The sealing ring, the first insulating ring and the second insulating ring are all made of glass fiber reinforced PEEK material.

8. According to claim 1, the novel ultra-high temperature hard electrode nipple is characterized by: The compensation ring is a metal grooved tube.

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