CN117307098A - A differential pressure wellhead chemical dosing device skid and its use method - Google Patents

Abstract

The invention relates to the technical field of oil field wellhead dosing devices, in particular to a differential pressure wellhead dosing device skid block and a use method thereof. The technical proposal is as follows: the medicine tank, the heating device and the filtering device are arranged in the cabinet body, the other side of the filtering device is connected to the heating device through a pipeline, the heating device is connected to the differential pressure transmitter and the jet flow medicine sucking device through a pipeline, the outlet end of the jet flow medicine sucking device is connected with the mixed well inlet pipeline, the other liquid inlet of the jet flow medicine sucking device is connected to the medicine tank through a pipeline and a check valve, and the integrating instrument is arranged on the upper side of the inner cavity of the cabinet body. The beneficial effects are that: 1. the invention adds the mixing pipe with the bell mouth structure, so that the liquid and the liquid medicine are mixed uniformly and then added into the wellhead of the oil well, the oil collecting and displacement effect is better, and the crude oil extraction rate is improved; 2. the water-medicine proportion is controlled through a mechanical structure, and the medicine adding amount can be increased and reduced along with the increase of the liquid input amount, so that scientific and reasonable medicine adding is realized.

Description

A differential pressure wellhead chemical dosing device skid and its use method

Technical field

The invention relates to the technical field of oilfield wellhead chemical dosing devices, and in particular to a differential pressure wellhead chemical dosing device skid and a method of use.

Background technique

In the development of oil fields, factors such as thick oil, wax formation, and corrosion are often encountered. Especially during periods of high water content, corrosion brings great difficulties to production. To control these problems, adding chemicals at the wellhead is the current solution. Effective and feasible methods in development, such as: demulsifiers, scale inhibitors, bactericides, corrosion inhibitors, surfactants, flocculants, coagulants, deoxidizers and other liquids.

Nowadays, the dosing device skid for injecting chemical liquid at the oilfield wellhead is generally injected by a single plunger pump. The required chemical liquid flow rate can be calculated through the wellhead water injection flow rate and the water-chemical ratio, and then the flow rate of the injected chemical liquid can be manually adjusted. The device skid has the following shortcomings: First, the water and chemical liquid are added separately, the mixing is uneven, and the oil collection and oil displacing effect is poor; second, because the cumulative flow rate of the chemical liquid added cannot be displayed, the water-chemical ratio cannot be accurately controlled to obtain the optimal The optimal water-medicine ratio achieves the most scientific and reasonable dosing; third, the injection flow of the medicinal solution can only be manually adjusted, and remote operation, control, and on-site debugging are not possible, which is time-consuming and laborious; if replaced with a plunger pump that can automatically adjust the flow , requiring higher fees.

Contents of the invention

The purpose of the present invention is to provide a differential pressure wellhead chemical dosing device skid and a method of use in view of the above-mentioned deficiencies in the prior art. The water-chemical ratio is controlled through a mechanical structure, and the amount of chemical added will increase as the amount of incoming liquid increases. Increase, decrease and decrease to achieve reasonable dosing, and the oil collection and oil displacement effect is better, improving the crude oil recovery rate.

The technical solution of the skid of a differential pressure wellhead chemical dosing device mentioned in the present invention is: it includes a chemical tank and a chemical feed pipeline, which also includes a heating device, a filter device, a sewage pipeline, a mixing well pipe, and an injection pipeline. Flow medicine device, totalizer, cabinet, differential pressure transmitter, medicine tank, heating device and filter device are installed in the cabinet. The water pipe is installed on the upper side of the filter device and the sewage pipe is installed on the lower side. The other side of the filtering device is connected to the heating device through a pipeline. The heating device is connected to the input end of the differential pressure transmitter through a pipeline. The output end of the differential pressure transmitter is connected to the jet flow drug suction device. The jet flow suction device The outlet end of the medicine device is connected to the mixing well inlet pipeline, the other liquid inlet of the jet flow medicine suction device is connected to the one-flow valve through the pipeline, and the other end of the one-flow valve is connected to the medicine tank through the medicine inlet pipeline. An integrator is installed on the upper side of the inner cavity of the cabinet.

Preferably, the above-mentioned medicine tank includes a tank body, an insulation layer, a medicine liquid outlet, a heating tape, a liquid level and temperature sensor, and a medicine liquid inlet. The outside of the tank body is provided with an insulation layer, and a heating tape is installed inside the insulation layer. , and the heating tape is wrapped around the tank; the inner cavity of the tank is equipped with a liquid level temperature sensor, the bottom of the tank is installed with a liquid outlet, and the top of the tank is provided with a liquid inlet.

Preferably, the above-mentioned filtering device includes a liquid outlet, a sewage outlet, a filter screen, a filter cover, a liquid pipe, a filter bracket and a housing. The lower side of the housing is provided with a liquid outlet, and the other side is provided with a liquid outlet. There is a sewage outlet, a liquid inlet pipe is provided on the upper side, a filter bracket is installed in the inner cavity of the housing, the filter is installed on the filter bracket, and a filter cover is provided on the top of the housing.

Preferably, the lower side of the above-mentioned filter cover is movably connected to the filter handle provided on the filter net, the top of the filter cover is provided with a knob, and the filter cover is threadedly connected to the upper end of the housing; the filter net The bracket is installed and fixed obliquely on the inner wall of the housing.

Preferably, the above-mentioned heating device includes a heating tank, a liquid outlet, a temperature transmitter, a pressure transmitter, an electric heating pipe, and a liquid inlet. The heating tank is provided with a liquid inlet on one side and a liquid inlet on the other side. For the liquid outlet, an electric heating tube is provided in the inner cavity of the heating tank, and a temperature transmitter and a pressure transmitter are provided on the top of the heating tank.

Preferably, the above-mentioned jet flow drug inhalation device includes a liquid inlet pipe, a spray pipe, a drug suction pipe, a mixing tube and a drug aspirator main body. One end of the drug aspirator body is connected to the liquid inlet pipe, and the other end is connected to the mixing pipe. , a drug suction pipe is provided on one side of the main body of the drug aspirator, and a spray pipe is fixed in the inner cavity of the liquid inlet pipe, and the spray head of the spray pipe is located in the inner cavity of the main body of the drug aspirator.

Preferably, one end of the above-mentioned injection head is connected to the end of the injection pipe through a tapered cavity connecting pipe, and the inner diameter of the injection head is smaller than the inner diameter of the injection pipe.

Preferably, the above-mentioned mixing tube includes a mixing tube cylinder, a drainage end, and a diffusion tube. One end of the mixing tube cylinder is provided with a drainage end, and the other end is provided with a diffusion tube with a bell mouth structure.

The method of using the differential pressure wellhead chemical dosing device skid mentioned in the present invention includes the following processes:

The first step is to hoist the skid of the differential pressure wellhead dosing device next to the wellhead via a crane, connect the water inlet pipe connected to the filter device to the water supply pipeline, and connect the mixed well inlet pipe connected to the jet flow drug suction device to the wellhead. At , connect the sewage pipe on the lower side of the filter device to the sewage pool through the pipeline;

In the second step, start the valves of the water supply pipeline, the mixing well pipeline and the medicine supply pipeline. The water enters the filtering device along the water supply pipeline. It is filtered and pressure stabilized through the filtering device, and then enters the inner cavity of the heating device. Since The heating device is equipped with an electric heating tube to heat the filtered water, and then it is sent to the jet flow drug suction device through the liquid outlet and a differential pressure transmitter. Among them, an orifice plate type is installed in the differential pressure transmitter. The throttling device causes the liquid to locally shrink near the throttling device, which increases the flow rate of the water and generates a pressure difference. The integrator calculates the instantaneous overflow flow rate and the accumulated flow rate, and then ejects it through the injection pipe at high speed. The inner cavity of the main body of the medicine container forms a vacuum zone, and the medicine liquid from the medicine tank is sucked into the mixing tube through the medicine inlet pipe, the one-flow valve and the medicine suction pipe. Finally, the liquid medicine mixture is added to the wellhead through the mixing well pipe;

In the third step, after the dosing is completed, close the valves of the water pipe, mixing well pipe and drug feed pipe, then open the filter cover of the filter device, take out the filter screen, pour out the filtered material, and the filter device The dirt at the bottom is discharged through the sewage pipeline for treatment, and the dosing of one oil well is completed. The skid of the differential pressure wellhead dosing device is then hoisted by a crane to another wellhead for dosing operations.

Compared with the prior art, the beneficial effects of the present invention are as follows:

1. The present invention adds a mixing tube with a bell mouth structure, so that the incoming liquid and chemical liquid are mixed evenly before being added to the wellhead of the oil well, so that the oil collection and oil displacement effect is better, and the crude oil recovery rate is improved;

2. The present invention controls the ratio of water and medicine through a mechanical structure. The amount of medicine added will increase with the increase of the incoming liquid volume and decrease with the decrease, thereby achieving scientific and reasonable dosing of medicine into the oil well;

3. The present invention also adds a calculator with a wireless data transmission module and a PLC control system, which can realize remote operation, is simple, fast and efficient, saving manpower and material resources; in addition, it adopts a skid-mounted structure to facilitate movement and complete the dosing of an oil well. , and then the invention is hoisted to another wellhead by a crane for dosing operation, which improves dosing efficiency.

Description of the drawings

Figure 1 is a schematic diagram of the overall structure of the present invention;

Figure 2 is a schematic diagram of the present invention in a top view;

Figure 3 is a schematic structural diagram of the pharmaceutical tank;

Figure 4 is a schematic structural diagram of the filtering device;

Figure 5 is a schematic structural diagram of the heating device;

Figure 6 is a schematic side structural view of the heating device;

Figure 7 is a schematic structural diagram of the jet stream medicine inhalation device;

Figure 8 is a schematic structural diagram of the mixing tube;

In the picture above: medicine tank 1, medicine feed pipe 2, heating device 3, filter device 4, sewage pipe 5, water pipe 6, mixing well pipe 7, jet flow drug suction device 8, calculator 9, Cabinet 10, differential pressure transmitter 11, one-flow valve 12, tank 1.1, insulation layer 1.2, liquid outlet 1.3, heating tape 1.4, liquid level temperature sensor 1.5, liquid inlet 1.6, heating tank 3.1, liquid Outlet 3.2, temperature transmitter 3.3, pressure transmitter 3.4, electric heating pipe 3.5, liquid inlet 3.6, liquid outlet 4.1, sewage outlet 4.2, filter 4.3, filter cover 4.4, liquid pipe 4.5, filter bracket 4.6, housing 4.7, filter handle 4.3.1, knob 4.4.1, liquid inlet pipe 8.1, injection pipe 8.2, suction pipe 8.3, mixing pipe 8.4, suction device body 8.5, spray head 8.2.1, cone Shape cavity connecting tube 8.2.2, mixing tube cylinder 8.4.1, drainage end 8.4.2, diffusion tube 8.4.3.

Detailed ways

The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described here are only used to illustrate and explain the present invention, and are not intended to limit the present invention.

Embodiment 1, with reference to Figures 1 to 8, a differential pressure wellhead chemical dosing device skid mentioned in the present invention includes a chemical tank 1 and a chemical feed pipeline 2, which also includes a heating device 3 and a filtering device 4 , sewage pipeline 5, mixing well pipeline 7, jet flow suction device 8, totalizer 9, cabinet 10, differential pressure transmitter 11. A lifting eye is installed on the top of the cabinet 10. The medicine tank 1, the heating device 3 and the filtering device 4 are installed inside. The water supply pipeline 6 is installed on the upper side of the filtering device 4, and the sewage pipeline 5 is installed on the lower side. The other side of the filtering device 4 is connected to the heating device through pipelines. 3. The heating device 3 is connected to the input end of the differential pressure transmitter 11 through a pipeline, the output end of the differential pressure transmitter 11 is connected to the jet flow drug suction device 8, and the outlet end of the jet flow drug suction device 8 is connected to the mixing The well inlet pipeline 7 is connected, and the other liquid inlet of the jet flow medicine suction device 8 is connected to the one-flow valve 12 through a pipeline. The other end of the one-flow valve 12 is connected to the medicine tank 1 through the medicine inlet pipeline 2. The cabinet An integrator 9 is installed on the upper side of the inner cavity of the body 10 .

Referring to Figure 3, the medicine tank 1 mentioned in the present invention includes a tank body 1.1, an insulation layer 1.2, a medicine liquid outlet 1.3, a heating tape 1.4, a liquid level temperature sensor 1.5 and a medicine liquid inlet 1.6. The external equipment of the tank 1.1 is There is an insulation layer 1.2, and a heating tape 1.4 is installed in the insulation layer 1.2, and the heating tape 1.4 is wrapped around the tank 1.1 for heating the liquid medicine; a liquid level temperature sensor 1.5 is installed in the inner cavity of the tank 1.1, and the liquid level is The temperature sensor 1.5 can realize high and low liquid level alarms, and can measure the temperature of the liquid to keep it at an appropriate temperature to prevent freezing or failure due to excessive temperature; a liquid outlet 1.3 is installed at the bottom of the tank 1.1, and a liquid outlet 1.3 is installed at the top of the tank 1.1. There are medicinal liquid imports 1.6.

Referring to Figure 4, the filter device 4 mentioned in the present invention includes a liquid outlet 4.1, a sewage outlet 4.2, a filter 4.3, a filter cover 4.4, a liquid pipe 4.5, a filter bracket 4.6 and a housing 4.7. The housing 4.7 There is a liquid outlet 4.1 on the lower side, a sewage outlet 4.2 on the other side, and a liquid pipe 4.5 on the upper side. A filter bracket 4.6 is installed in the inner cavity of the housing 4.7, and the filter 4.3 is installed on the filter bracket 4.6. On the top of the housing 4.7, a filter cover 4.4 is provided, and the filter cover 4.4 can be designed to be threadedly connected to the upper end of the housing 4.7.

Among them, the lower side of the above-mentioned filter cover 4.4 is movably connected to the filter handle 4.3.1 provided on the filter 4.3, so that when the filter cover 4.4 is unscrewed, the filter device 4 can be quickly opened, and the filter 4.3 can be taken out and cleaned. To remove impurities, a knob 4.4.1 is provided on the top of the filter cover 4.4, and the filter cover 4.4 is threadedly connected to the upper end of the housing 4.7; the filter bracket 4.6 is tilted and fixed to the inner wall of the housing 4.7.

Referring to Figures 5 and 6, the heating device 3 mentioned in the present invention includes a heating tank 3.1, a liquid outlet 3.2, a temperature transmitter 3.3, a pressure transmitter 3.4, an electric heating tube 3.5, and a liquid inlet 3.6. The heating tank One side of the body 3.1 is provided with a liquid inlet 3.6, and the other side is provided with a liquid outlet 3.2. An electric heating tube 3.5 is provided in the inner cavity of the heating tank 3.1. A temperature transmitter 3.3 is provided on the top of the heating tank 3.1. Pressure transmitter 3.4;

In addition, the heating device 3 is designed with a low-in and high-out structure to prevent the electric heating tube 3.5 from being damaged by dry burning; the temperature transmitter 3.3 is used to measure the temperature of the liquid in the tank and feed it back to the calculator 9, which controls the calculator 9. The start and stop of the electric heating tube 3.5 keeps the temperature of the liquid in the heating tank 3.1 within the required temperature range.

Referring to Figure 7, the jet flow drug inhalation device 8 mentioned in the present invention includes a liquid inlet pipe 8.1, a spray pipe 8.2, a drug suction pipe 8.3, a mixing tube 8.4 and a drug aspirator body 8.5. One end of the drug aspirator body 8.5 Connect the liquid inlet pipe 8.1, and the other end is connected to the mixing pipe 8.4. There is a drug suction pipe 8.3 on one side of the drug inhaler body 8.5. A spray pipe 8.2 is fixed in the inner cavity of the liquid inlet pipe 8.1. The spray pipe 8.2 The spray head 8.2.1 is located in the inner cavity of the medicine aspirator body 8.5.

Among them, one end of the above-mentioned injection head 8.2.1 is connected to the end of the injection pipe 8.2 through a tapered cavity connecting pipe 8.2.2, and the inner diameter of the injection head 8.2.1 is smaller than the inner diameter of the injection pipe 8.2.

Referring to Figure 8, the mixing tube 8.4 mentioned in the present invention includes a mixing tube cylinder 8.4.1, a drainage end 8.4.2, and a diffusion tube 8.4.3. One end of the mixing tube cylinder 8.4.1 is provided with a drainage end 8.4. 2. The other end is equipped with a diffuser tube 8.4.3 with a bell mouth structure.

In addition, the calculator 9 is a commercially available product, consisting of a PLC control system, a signal collection and transmission module, a wireless data transmission module, etc. The PLC control system can collect and display signals such as temperature, pressure, pressure difference, liquid level, etc., and its internal Embedded with flow calculation formulas such as Bernoulli's equation, instantaneous flow and cumulative flow can be calculated; the wireless data transmission module can wirelessly transmit data to each platform and receive data adjustments from each platform.

The method of using the differential pressure wellhead chemical dosing device skid mentioned in the present invention includes the following processes:

The first step is to hoist the skid of the differential pressure wellhead chemical dosing device next to the wellhead by a crane, connect the water inlet pipe 6 connected to the filter device 4 to the water supply pipeline, and connect the mixing well pipe connected to the jet flow chemical suction device 8 7 is connected to the wellhead, and the sewage pipeline 5 on the lower side of the filter device 4 is connected to the sewage pool through the pipeline;

In the second step, start the valves of the water inlet pipeline 6, the mixing well inlet pipeline 7 and the medicine inlet pipeline 2. The water enters the filter device 4 along the water inlet pipeline 6. It is filtered and pressure stabilized through the filter device 4, and then enters In the inner cavity of the heating device 3, since the heating device 3 is equipped with an electric heating tube 3.5, the filtered water is heated, and then is sent to the jet flow medicine inhalation device 8 through the liquid outlet 3.2 and the differential pressure transmitter 11. Among them, an orifice-type throttling device is installed in the differential pressure transmitter 11. The liquid causes local contraction near the throttling device, which increases the flow rate of the water and generates a pressure difference. The calculator 9 calculates the instantaneous overflow flow rate and product volume. Calculate the flow rate, and then eject it at high speed through the injection pipe 8.2, forming a vacuum zone in the inner cavity of the medicine inhaler body 8.5, and inhale the medicine liquid from the medicine tank 1 through the medicine inlet pipe 2, the one-flow valve 12 and the medicine suction pipe 8.3 to the mixing pipe 8.4. Finally, the water and chemical mixture is added to the wellhead through the mixing well pipe 7;

In the third step, after the dosing is completed, close the valves of the water pipe 6, the mixing well pipe 7 and the medicine feed pipe 2, then open the filter cover 4.4 of the filter device 4, take out the filter 4.3, and remove the filtered material. Pour it out, and the dirt at the bottom of the filter device 4 is discharged through the sewage pipe 5 for treatment, completing the dosing of one oil well, and then hoisting the skid of the differential pressure wellhead dosing device to another wellhead via a crane for dosing operations. .

The above are only some of the preferred embodiments of the present invention, and any person familiar with the art may make modifications using the technical solutions described above or modify them into equivalent technical solutions. Therefore, corresponding simple modifications or equivalent transformations based on the technical solution of the present invention all fall within the scope of protection claimed by the present invention.

Claims (9)

1. The utility model provides a pressure differential well head dosing device sledge piece, includes medicament jar (1) and advances medicine pipeline (2), characterized by: still include heating device (3), filter equipment (4), blow off pipeline (5), mix well pipe way (7), jet flow medicine suction device (8), totalizer (9), cabinet body (10), differential pressure transmitter (11), install medicament jar (1), heating device (3) and filter equipment (4) in cabinet body (10), water pipe way (6) are installed to the upside of filter equipment (4), and blow off pipeline (5) are installed to the downside, pass through pipeline connection to heating device (3) at the opposite side of filter equipment (4), be connected to the input of differential pressure transmitter (11) through the pipeline on heating device (3), jet flow medicine suction device (8) are connected to the output of differential pressure transmitter (11), the exit end and the mix well pipe way (7) of jet flow medicine suction device (8) are connected, another inlet of jet flow medicine suction device (8) is through pipeline connection uniflow valve (12), and the other end of uniflow valve (12) is connected to medicament jar (1) through advancing medicine pipeline (2), the inner chamber upside of cabinet body (10) installs totalizer (9).

2. The differential pressure wellhead dosing device skid of claim 1, wherein: the medicament tank (1) comprises a tank body (1.1), a heat preservation layer (1.2), a liquid medicine outlet (1.3), a heat tracing belt (1.4), a liquid level temperature sensor (1.5) and a liquid medicine inlet (1.6), wherein the heat preservation layer (1.2) is arranged outside the tank body (1.1), the heat tracing belt (1.4) is arranged in the heat preservation layer (1.2), and the heat tracing belt (1.4) is wound on the tank body (1.1); the liquid level temperature sensor (1.5) is arranged in the inner cavity of the tank body (1.1), the liquid medicine outlet (1.3) is arranged at the bottom of the tank body (1.1), and the liquid medicine inlet (1.6) is arranged at the top of the tank body (1.1).

3. The differential pressure wellhead dosing device skid of claim 2, wherein: the filtering device (4) comprises a liquid outlet (4.1), a drain outlet (4.2), a filter screen (4.3), a filter cover (4.4), a liquid inlet pipe (4.5), a filter screen support (4.6) and a shell (4.7), wherein the liquid outlet (4.1) is arranged at the lower side of the shell (4.7), the drain outlet (4.2) is arranged at the other side of the shell, the liquid inlet pipe (4.5) is arranged at the upper side of the shell, the filter screen support (4.6) is arranged in an inner cavity of the shell (4.7), the filter screen (4.3) is arranged on the filter screen support (4.6), and the filter cover (4.4) is arranged at the top of the shell (4.7).

4. A differential pressure wellhead dosing device skid as defined in claim 3, wherein: the lower side of the filter cover (4.4) is movably connected with a filter screen handle (4.3.1) arranged on the filter screen (4.3), a knob (4.4.1) is arranged at the top of the filter cover (4.4), and the filter cover (4.4) is in threaded connection with the upper end of the shell (4.7); the filter screen bracket (4.6) is obliquely arranged and fixed with the inner wall of the shell (4.7).

5. The differential pressure wellhead dosing device skid of claim 4, wherein: heating device (3) including heating jar body (3.1), liquid export (3.2), temperature transmitter (3.3), pressure transmitter (3.4), electric heating pipe (3.5), liquid import (3.6), one side of heating jar body (3.1) is equipped with liquid import (3.6), the opposite side is equipped with liquid export (3.2), is equipped with electric heating pipe (3.5) at the inner chamber of heating jar body (3.1), is equipped with temperature transmitter (3.3) and pressure transmitter (3.4) at the top of heating jar body (3.1).

6. The differential pressure wellhead dosing device skid of claim 5, wherein: jet flow medicine suction device (8) including coming liquid entry pipe (8.1), jet pipe (8.2), medicine suction pipe (8.3), hybrid tube (8.4) and medicine suction apparatus main part (8.5), liquid entry pipe (8.1) is connected to one end of medicine suction apparatus main part (8.5), hybrid tube (8.4) are connected to the other end, are equipped with medicine suction pipe (8.3) in one side of medicine suction apparatus main part (8.5), fixed jet pipe (8.2) in the inner chamber that comes liquid entry pipe (8.1), jet head (8.2.1) of jet pipe (8.2) are located the inner chamber of medicine suction apparatus main part (8.5).

7. The differential pressure wellhead dosing device skid of claim 6, wherein: one end of the injection head (8.2.1) is connected with the tail end of the injection pipe (8.2) through a conical cavity connecting pipe (8.2.2), and the inner diameter of the injection head (8.2.1) is smaller than the inner diameter of the injection pipe (8.2).

8. The differential pressure wellhead dosing device skid of claim 7, wherein: the mixing tube (8.4) comprises a mixing tube body (8.4.1), a drainage end (8.4.2) and a diffusion tube (8.4.3), wherein one end of the mixing tube body (8.4.1) is provided with the drainage end (8.4.2), and the other end of the mixing tube body is provided with the diffusion tube (8.4.3) with a horn mouth structure.

9. A method of using the differential pressure wellhead dosing device skid of claim 8, comprising the steps of:

hoisting a differential pressure type wellhead dosing device skid block beside a wellhead through a crane, connecting an incoming water pipeline (6) connected with a filtering device (4) with a water supply pipeline, connecting a mixed well inlet pipeline (7) connected with a jet flow drug sucking device (8) to the wellhead, and connecting a sewage pipeline (5) at the lower side of the filtering device (4) into a sewage pool through a pipeline;

secondly, starting valves of an incoming water pipeline (6), a mixed well pipeline (7) and a medicine inlet pipeline (2), enabling water to enter a filtering device (4) along the incoming water pipeline (6), filtering and stabilizing pressure through the filtering device (4), then entering an inner cavity of a heating device (3), heating filtered water due to the fact that an electric heating pipe (3.5) is arranged in the heating device (3), sending the filtered water into a jet medicine suction device (8) through a liquid outlet (3.2) and a differential pressure transmitter (11), wherein a orifice plate type throttling device is additionally arranged in the differential pressure transmitter (11), liquid is locally contracted near the throttling device, the flow speed of the water is increased, pressure difference is generated, an instantaneous overcurrent flow and an integrating flow are calculated by an integrating instrument (9), then, the water is sprayed out at a high speed through an injection pipe (8.2), a vacuum area is formed in the inner cavity of a medicine suction device main body (8.5), liquid medicine from a medicine tank (1) is sucked into the mixed well pipeline (8.4) through the medicine inlet pipeline (2), a uniflow flow valve (12) and the medicine suction pipe (8.3), and finally, and the mixed liquid is added into a well mouth (7);

and thirdly, after the dosing is finished, closing valves of the water inlet pipeline (6), the mixed well inlet pipeline (7) and the dosing pipeline (2), opening a filter cover (4.4) of the filter device (4), taking out the filter screen (4.3), pouring out the filtered matters, discharging dirt at the bottom of the filter device (4) through the sewage discharging pipeline (5), treating, finishing the dosing of one oil well, and hoisting a differential pressure type wellhead dosing device skid block to another wellhead through a crane for dosing operation.