Oil heater heat preservation device for underground operation

Abstract

The oil heater heat preservation device comprises a heat preservation oil tank, an anti-explosion heater, an anti-explosion gear pump, an anti-explosion control cabinet and a heat preservation hydraulic control pipeline. The anti-explosion heater is electrically connected with the heat preservation oil tank and heats the heat conduction oil in the heat preservation oil tank. The explosion-proof gear pump is respectively connected with the heat-insulating oil tank and the heat-insulating hydraulic control pipeline, so that heat-conducting oil in the heat-insulating oil tank is pumped into the heat-insulating hydraulic control pipeline; the anti-explosion gear pump and the temperature control sensor are both in circuit connection with the anti-explosion control cabinet, so that the anti-explosion control cabinet can control working modes and parameters of the heat preservation oil tank and the anti-explosion gear pump; the device can be subjected to heat preservation in extremely cold weather of-25 DEG C, meanwhile, the generated hydrate or ice blockage condition is treated, and a non-well-killing, low-cost and efficient-construction device heat preservation technology is formed.

Description

Technical Field

[0001] The invention belongs to the technical field of oil drilling downhole operation, and in particular relates to an oil radiator insulation device for downhole operation. Background Art

[0002] At present, ice blockage occurs during the blowout process of operating wells in the Changqing area, and ice blockage also occurs during the pressure-lowering completion string process. As a result, the tubing hanger cannot be put into place due to hydrates during the pressure-lowering completion string process. Although it was discovered in time, the problem of ice blockage and freezing near the wellhead could not be solved in time due to the lack of necessary equipment on site, posing a serious safety hazard.

[0003] At present, the long-term common insulation device for winter construction in Changqing area is the electric belt insulation device. This insulation device requires the use of a generator all day long. The 220V or 380V high voltage electricity of the generator is converted into 24V or 36V low voltage electricity through a transformer, and then the electric belt generates heat. The outer layer uses felt, sponge, and waterproof tape for insulation to achieve the purpose of insulation and antifreeze of on-site equipment. This insulation measure has many defects: 1. Low heating temperature; the actual measurement of the temperature generated by the electric belt is about 20℃. If the temperature is too high, it will damage the electric heating performance of the cable; 2. Slow heating speed; due to low voltage control, the heating speed of the electric belt can only meet the basic use requirements in more than 4 hours when used on site; 3. Short service life; due to the poor outdoor use conditions on site, the basic service life is 10-12 months; 4. Single operation control mode; it can only be controlled by a temperature control switch. If the temperature control switch is damaged, it will be unusable or even burn the electric belt.

[0004] In addition, the way to deal with dangerous situations such as ice blockage and freezing is to inject alcohol at the wellhead, use a low-furnace truck to heat the wellhead, or use high-temperature well washing fluid to wash and pressure the well. However, the cycle is relatively long, the cost is high, the effect is average, and the well control safety risk is very high during the period. In extremely cold weather, these conventional practices cannot meet the construction requirements. Summary of the invention

[0005] The present invention solves the problems of conventional heat preservation in winter and the generation of hydrates and ice blockage at the wellhead. The developed oil-filled radiator heat preservation device can insulate the equipment in extremely cold weather at -25°C, and at the same time deal with the generated hydrates or ice blockage, forming an equipment heat preservation technology that does not require well pressure, is low-cost, and has high-efficiency construction.

[0006] The present invention solves the technical problem by adopting the following technical solutions:

[0007] An oil-filled heat preservation device for underground operations comprises a heat preservation oil tank, an explosion-proof heater, an explosion-proof gear pump, an explosion-proof control cabinet, and a heat preservation hydraulic control pipeline; the explosion-proof heater is electrically connected to the heat preservation oil tank and heats the heat transfer oil in the heat preservation oil tank; the explosion-proof gear pump is respectively connected to the heat preservation oil tank and the heat preservation hydraulic control pipeline, so as to pump the heat transfer oil in the heat preservation oil tank into the heat preservation hydraulic control pipeline;

[0008] The explosion-proof gear pump and the temperature control sensor are both connected to the explosion-proof control cabinet circuit, so that the explosion-proof control cabinet can control the working mode and parameters of the insulation oil tank and the explosion-proof gear pump;

[0009] The insulation layers are arranged outside the insulation hydraulic control pipeline and the insulation oil tank, and the insulation layers are respectively made of polyester-cotton wear-resistant canvas material, cotton felt, nitrile foam rubber (single-sided aluminum foil), and polymer nano-knife scraper cloth from inside to outside.

[0010] Furthermore, the explosion-proof gear pump is provided with more than 5 outlets, and each outlet is provided with a check valve and switch control; the displacement requirement is not greater than 10L / min, and the head requirement is greater than 30m; there are filtering devices at the return liquid and inlet joints; and a temperature control sensor is installed at the return liquid pipeline.

[0011] Furthermore, the thermal insulation liquid control pipeline includes a plurality of thermal insulation oil guide coils, and both ends of the thermal insulation oil guide coils are provided with ejectors to prevent liquid backflow; the thermal insulation liquid control pipeline can accommodate a temperature range of -15°C-100°C.

[0012] Furthermore, the thermal insulation oil tank has a capacity of 180L-200L and is filled with L-QC320 heat transfer oil.

[0013] Furthermore, it also includes a heating device base, the thermal insulation oil tank is installed on the heating device base, and the heating device base has moving and locking functions.

[0014] Furthermore, the heating control of the explosion-proof control cabinet is explosion-proofed by a leakage protection device, and the temperature control of the explosion-proof control cabinet can be freely adjusted, and the temperature control switch can switch between automatic start and stop and manual start and stop.

[0015] Furthermore, the insulated oil tank is provided with a liquid return joint, which is connected to the liquid return pipeline of the explosion-proof gear pump to form a pumping circuit.

[0016] Furthermore, a partition is provided inside the insulated oil tank to prevent severe shaking of the liquid during transportation and damage to the equipment.

[0017] Furthermore, the lower part of the insulated oil tank is provided with a sewage outlet with a diameter not less than Φ75mm.

[0018] Furthermore, a heat-insulating layer is provided outside the heat-insulating oil tank.

[0019] The advantages and positive effects of the present invention are:

[0020] The present invention uses electric energy to heat a special oil heater product (L-QC320 heat transfer oil) to a predetermined set temperature through an explosion-proof heating device, and then uses a high-pressure variable frequency gear pump as a power source to conduct heat through a high-temperature and high-pressure resistant hydraulic pipeline. At the same time, it is used in conjunction with a thermal insulation jacket composed of 4 layers of different materials to achieve a good effect of heat preservation of the equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The technical solution of the present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments, but it should be understood that these drawings are designed only for explanation purposes and are not intended to limit the scope of the present invention. In addition, unless otherwise specified, these drawings are intended only to conceptually illustrate the structural configurations described herein and are not necessarily drawn to scale.

[0022] Figure 1 A front view of an oil radiator heat preservation device for underground operations provided by an embodiment of the present invention;

[0023] Figure 2 A top view of an oil radiator heat preservation device for underground operations provided by an embodiment of the present invention;

[0024] Figure 3 This is a left side view of an oil radiator insulation device for underground operations provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0025] First of all, it should be noted that the specific structure, features and advantages of the present invention will be specifically described below by way of example, but all descriptions are only for illustration and should not be understood as limiting the present invention in any way. In addition, any single technical feature described or implied in the embodiments mentioned herein, or any single technical feature displayed or implied in the drawings, can still be combined or deleted between these technical features (or their equivalents) to obtain more other embodiments of the present invention that may not be directly mentioned in this document. In addition, in order to simplify the drawings, the same or similar technical features may be marked only in one place in the same drawing.

[0026] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application may be combined with each other.

[0027] Example 1

[0028] The oil-filled heat preservation device for underground operations provided in this embodiment includes a heat preservation oil tank, an explosion-proof heater, an explosion-proof gear pump, an explosion-proof control cabinet, and a heat preservation hydraulic control pipeline; the explosion-proof heater is electrically connected to the heat preservation oil tank and heats the heat transfer oil in the heat preservation oil tank, the heat preservation oil tank has a volume of 180L-200L and has L-QC320 heat transfer oil built in; the explosion-proof gear pump is respectively connected to the heat preservation oil tank and the heat preservation hydraulic control pipeline, so as to realize pumping the heat transfer oil in the heat preservation oil tank into the heat preservation hydraulic control pipeline;

[0029] The explosion-proof gear pump and the temperature control sensor are both connected to the explosion-proof control cabinet circuit, so that the explosion-proof control cabinet can control the working mode and parameters of the insulation oil tank and the explosion-proof gear pump;

[0030] The insulation layers are arranged outside the insulation hydraulic control pipeline and the insulation oil tank, and the insulation layers are respectively made of polyester-cotton wear-resistant canvas material, cotton felt, nitrile foam rubber (single-sided aluminum foil), and polymer nano-knife scraper cloth from inside to outside.

[0031] It should be noted that the explosion-proof gear pump is provided with more than 5 outlets, and each outlet is equipped with a check valve and switch control; the displacement requirement is not more than 10L / min, and the head requirement is greater than 30m; there are filtering devices at the return liquid and inlet joints; a temperature control sensor is installed at the return liquid pipeline; a return liquid joint is provided on the insulated oil tank, which is connected to the return liquid pipeline of the explosion-proof gear pump to form a pumping circuit.

[0032] The thermal insulation liquid control pipeline comprises a plurality of thermal insulation oil guide coils, and both ends of the thermal insulation oil guide coils are provided with ejectors to prevent liquid backflow; the thermal insulation liquid control pipeline can accommodate a temperature range of -15°C to 100°C.

[0033] The heating control of the explosion-proof control cabinet is explosion-proofed by a leakage protection device, and the temperature control of the explosion-proof control cabinet can be freely adjusted, and the temperature control switch can switch between automatic start and stop and manual start and stop.

[0034] It also includes a heating device base, the insulated oil tank is installed on the heating device base, and the heating device base has moving and locking functions; a partition is arranged inside the insulated oil tank to prevent severe shaking of the liquid during transportation and damage to the equipment; a sewage outlet is arranged at the bottom of the insulated oil tank, and the diameter is not less than Φ75mm; an insulation structure is arranged on the outside of the insulated oil tank.

[0035] Example 2

[0036] like Figure 1 , 2As shown in 3, the oil-filled heat preservation device for underground operation provided in this embodiment includes a heat preservation oil tank A, an explosion-proof heater B, an explosion-proof gear pump C, an explosion-proof control cabinet, and a heat preservation hydraulic control pipeline D; the explosion-proof heater is electrically connected to the heat preservation oil tank and heats the heat transfer oil in the heat preservation oil tank. The heat preservation oil tank has a volume of 180L-200L and has L-QC320 heat transfer oil built in; the explosion-proof gear pump is respectively connected to the heat preservation oil tank and the heat preservation hydraulic control pipeline, so as to realize pumping the heat transfer oil in the heat preservation oil tank into the heat preservation hydraulic control pipeline;

[0037] The explosion-proof gear pump and the temperature control sensor are both connected to the explosion-proof control cabinet circuit, so that the explosion-proof control cabinet can control the working mode and parameters of the thermal insulation oil tank and the explosion-proof gear pump.

[0038] The relevant attachments are shown in Table 1:

[0039] Table 1 Attachment Name

[0040]

[0041] Related attachments:

[0042] ① Insulated oil storage tank A:

[0043] Capacity 180L-200L; stainless steel material is used, and the anti-corrosion level is higher than that of ordinary steel products; partitions are installed inside to prevent severe shaking of liquid during transportation and damage to equipment; there are oil filling port 1 and air vent 2 on the top, return liquid joint 3 and oil outlet 4 on the bottom, and sewage outlet 5, with a diameter of not less than Φ75mm; there is an insulation layer 6 on the outside, and the insulation layer material is mainly divided into 4 layers, from inside to outside, respectively, polyester-cotton anti-wear canvas material, cotton felt, nitrile foam rubber (single-sided aluminum foil), polymer nano-knife scraper cloth; the material used is thermal oil; the bottom of the water tank is slightly inclined; the water supply is more than 5cm from the bottom.

[0044] ②Heating device base:

[0045] Equipped with a hook for placing the oil guide pipe; the base, hanging points and box meet the lifting requirements; the base has a qualified ground pile; the base has moving and locking functions.

[0046] ③Insulated oil-conducting coil:

[0047] Each pipeline is 25m long, with pins at both ends to prevent liquid backflow; the built-in diameter is not less than Φ12mm, and the temperature range is -15℃∽100℃.

[0048] ④Explosion-proof control cabinet:

[0049] The operating voltage is 220-380V, the power is within 10KW, and the time to heat the water tank to 80℃ is less than 1h; the heating control must be explosion-proof and have more than 2 leakage protection devices; the temperature control can be adjusted freely, and the temperature control switch can switch between automatic start and stop and manual start and stop; it is convenient to disassemble, maintain, inspect and replace accessories; there are waterproof and rainproof measures; the markings are clear, there is a main switch, and one machine has one switch.

[0050] ⑤Explosion-proof gear pump:

[0051] Variable frequency gear pumps are preferred; the number of outlets is set to more than 5, and each outlet is equipped with a check valve and switch control; the displacement requirement is not more than 10L / min, and the head requirement is more than 30m; there are filtering devices at the return and inlet joints; equipped with tees and crosses, which can be connected to more than 5 pipelines; leaving disassembly space for easy disassembly, maintenance and replacement of accessories; the motor power is not more than 2KW, and there are protective measures for the rotating parts; a temperature control sensor is installed on the return pipeline.

[0052] Among them, the protective thermal insulation outer garment is the thermal insulation layer, and the thermal insulation layer is made of polyester-cotton wear-resistant canvas material, cotton felt, nitrile foam rubber (single-sided aluminum foil), and polymer nano-knife scraper cloth from the inside to the outside.

[0053] Compared with the conductive electric heating tape insulation device, the oil-filled heating tape insulation device in this embodiment has the following characteristics:

[0054] The set temperature of the oil-filled radiator insulation device is much higher than the set temperature of the electric belt insulation device. The electric belt insulation device is generally 30∽40℃, while the oil-filled radiator insulation device can reach 70∽80℃; moreover, the oil-filled radiator insulation device can maintain the set temperature for a long time.

[0055] Moreover, through the control of the explosion-proof control cabinet and software control, the oil-filled heater insulation device can set the insulation cycle in three ways (circulation pressure, electric pump speed, and circulation temperature). This is more reasonable than the electric belt insulation device which can only be controlled by temperature alone. The electric belt insulation device will not work once the temperature control switch is damaged, which can effectively avoid the influence of insufficient terminal temperature of the electric belt insulation device due to the long distance. The heating speed of the oil-filled heater insulation device is much higher than that of the electric belt insulation device. The heating speed of the electric belt insulation device should normally be more than 2 hours to meet the use requirements, while the oil-filled heater insulation device only needs about 20 minutes to meet the use requirements. In addition, the oil-filled heater insulation device can be modulated to a high temperature mode, which can quickly solve the problem of some hydrates or ice blockages, and the temperature of the electric belt insulation device is far from meeting the use requirements.

[0056] The most important thing is that the materials used in the oil-filled radiator insulation device can be recycled and reused, and its lifespan is much longer than the materials used in the electric belt insulation device; this oil-filled radiator insulation device has the advantages of long service life, convenient transportation, flexible use, convenient on-site installation, simple operation, and convenient operation and management.

[0057] The above embodiments describe the present invention in detail, but the contents are only preferred embodiments of the present invention and cannot be considered to limit the scope of the present invention. All equivalent changes and improvements made within the scope of the present invention should still fall within the scope of the present invention.

Claims

1. Oil radiator insulation device for underground operation, characterized in that: It includes an insulated oil tank, an explosion-proof heater, an explosion-proof gear pump, an explosion-proof control cabinet, and an insulated hydraulic control pipeline; the explosion-proof heater is electrically connected to the insulated oil tank and heats the heat transfer oil in the insulated oil tank; the explosion-proof gear pump is respectively connected to the insulated oil tank and the insulated hydraulic control pipeline, so as to pump the heat transfer oil in the insulated oil tank into the insulated hydraulic control pipeline; The explosion-proof gear pump and the temperature control sensor are both connected to the explosion-proof control cabinet circuit, so that the explosion-proof control cabinet can control the working mode and parameters of the insulation oil tank and the explosion-proof gear pump; The insulation layers are arranged outside the insulation hydraulic control pipeline and the insulation oil tank, and the insulation layers are respectively made of polyester-cotton wear-resistant canvas material, cotton felt, nitrile foam rubber, and polymer nano-knife scraper cloth from inside to outside.

2. The oil radiator insulation device for underground operation according to claim 1, characterized in that: The explosion-proof gear pump is provided with more than 5 outlets, and each outlet is equipped with a check valve and switch control; the displacement requirement is not greater than 10L / min, and the head requirement is greater than 30m; there are filtering devices at the return liquid and inlet joints; and a temperature control sensor is installed at the return liquid pipeline.

3. The oil radiator insulation device for underground operation according to claim 1, characterized in that: The thermal insulation liquid control pipeline comprises a plurality of thermal insulation oil guide coils, and both ends of the thermal insulation oil guide coils are provided with ejectors to prevent liquid backflow; the thermal insulation liquid control pipeline can accommodate a temperature range of -15°C to 100°C.

4. The oil radiator insulation device for underground operation according to claim 1, characterized in that: The thermal insulation oil tank has a capacity of 180L-200L and is filled with L-QC320 heat transfer oil.

5. The oil radiator insulation device for underground operation according to claim 1, characterized in that: It also includes a heating device base, the thermal insulation oil tank is installed on the heating device base, and the heating device base has moving and locking functions.

6. The oil radiator insulation device for underground operation according to claim 1, characterized in that: The heating control of the explosion-proof control cabinet is explosion-proofed by a leakage protection device, and the temperature control of the explosion-proof control cabinet can be freely adjusted, and the temperature control switch can switch between automatic start and stop and manual start and stop.

7. The oil radiator insulation device for underground operation according to claim 1, characterized in that: The heat-insulating oil tank is provided with a liquid return joint, which is connected with the liquid return pipeline of the explosion-proof gear pump to form a pumping circuit.

8. The oil radiator heat preservation device for underground operation according to claim 1, characterized in that: The thermal insulation oil tank is provided with a partition plate to prevent the liquid from shaking severely during transportation and damaging the equipment.

9. The oil radiator heat preservation device for underground operation according to claim 1, characterized in that: The lower part of the thermal insulation oil tank is provided with a sewage outlet, the diameter of which is not less than Φ75mm.

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