Novel oil well packing box

Abstract

The invention discloses a packing box capable of metering crude oil leakage at an oil field wellhead, which relates to the field of oil extraction equipment of petroleum machinery and comprises a polished rod, a metering ring, a packing box cover, an oil storage tank, a packing, a packing box body and a wellhead device, the metering ring is mounted on the polished rod, and the polished rod reciprocates up and down in the center of the packing box during oil extraction. An oil storage tank is arranged on the upper portion of the packing box cover, the lower portion of the packing box cover is connected with the upper portion of the packing box body through screw threads, the lower portion of the packing box body is connected with a wellhead device through screw threads, an elastic packing is installed in the packing box body, and after the packing is pressed by the packing box cover, the functions of sealing a wellhead and preventing crude oil from leaking are achieved. During oil extraction work, along with abrasion between a polished rod and packing, when the packing box starts slight leakage, it is not needed that the packing box needs to be tightened like a common packing box, leaked crude oil enters an oil storage groove in the upper portion of the packing box cover, the quantity of the leaked crude oil is displayed on a metering ring, and when the leakage amount reaches a certain degree, the packing box can be tightened, so that the packing box is not required to be tightened. Therefore, the service life of the packing and the polish rod is greatly prolonged, energy consumption is reduced, environment is protected, labor intensity of workers is reduced, and crude oil yield is increased.

Description

TECHNICAL FIELD

[0001] The present application relates to oilfield wellhead device, particularly to a packing box installed on the upper part of the wellhead device. BACKGROUND

[0002] The packing box is a device installed on the oilfield wellhead to prevent oil leakage. The traditional packing box is composed of a packing box body, a packing, and a packing box cover. The lower part of the packing box cover is connected to the packing box body by a screw thread. The packing box body contains a packing with high elasticity. The lower part of the packing box body is connected to the wellhead device by a screw thread. In the oil production process, the elastic packing is compressed in the packing box body by the packing box cover and is sealed on the polished rod of the sucker rod. This effectively prevents oil from being brought out of the wellhead and polluting the equipment and environment during the up-and-down reciprocating movement of the polished rod.

[0003] In production practice, the gap between the packing and the polished rod becomes larger due to the daily wear and tear of the packing. Oil will leak from the gap between the packing and the polished rod. Even slight leakage will quickly pollute the wellhead. This requires the oil production worker to frequently tighten the packing, which will cause a large amount of damage to the packing. Frequent replacement of the packing also increases the labor intensity of the worker and affects the normal production of the oilfield. Moreover, the long-term over-tightening of the packing will cause greater wear and tear to the polished rod of the sucker rod, resulting in damage and increased energy consumption of the oil well. SUMMARY

[0004] The purpose of the present application is to scientifically design a new type of packing box that prolongs the service life of the packing and the polished rod, reduces energy consumption, and reduces the labor intensity of the worker on the basis of the traditional packing and structure.

[0005] The present application is achieved in this way. The new type of packing box of the present application is installed on the traditional packing box. A cylindrical oil storage tank 4 is installed on the polished rod 1. A metering ring 2 is installed on the polished rod 1. When slight leakage occurs in the packing box during the oil production process, the leaked oil will be stored in the oil storage tank 4 without polluting the wellhead. When the amount of leakage reaches the middle of the metering ring 2, the oil production worker needs to pay attention to observation, but still does not need to tighten the packing box cover 3. When the amount of leakage reaches the top of the metering ring 2, the oil production worker can adjust the tightness of the packing 5 in time. The force should be adjusted to the extent that the packing 5 is slightly leaking or not leaking. The packing 5 should not be over-tightened. This maximizes the reduction of friction between the packing 5 and the polished rod 1 and collects the oil in the oil storage tank 4 to clean the metering ring 2, which is recycled. This greatly prolongs the service life of the packing 5 and achieves the purposes of reducing the labor intensity of the worker, preventing pollution, prolonging the production time of the oil well, reducing energy consumption, and prolonging the service life of the polished rod 1. This method of directly detecting the amount of leakage has lower cost and higher safety than other methods of detecting the amount of leakage. The amount of leakage can be adjusted. BRIEF DESCRIPTION OF DRAWINGS

[0006] Figure 1 This embodiment shows a schematic diagram of the structure of the novel packing box.

[0007] In the diagram, 1 is the polished rod; 2 is the metering ring; 3 is the packing box cover; 4 is the oil storage tank; 5 is the packing; 6 is the packing box body; and 7 is the wellhead device. Detailed Implementation

[0008] Example 1: A wellhead packing box that can intuitively measure leakage. Figure 1 The diagram shows the overall structure of the new packing box. If the oil storage tank 4 and the metering ring 2 are removed, it will show a traditional wellhead packing box.

[0009] Among them, the diameter of the light rod 1 is 25mm, and it can move up and down along the center hole of the packing box.

[0010] The measuring ring 3 has an inner diameter of 22mm and a height of 130mm with graduations. It has a slit on one side that is open at both the top and bottom. The material is an oil- and water-repellent elastic material with a bright color.

[0011] After the slit is opened, the metering ring 2 is stuck on the outer wall of the polished rod 2. When the polished rod 2 is in the bottom dead center working position, the bottom of the metering ring 2 is flush with the bottom of the oil storage tank 4.

[0012] The oil storage tank 4 has a height of 150mm, an inner diameter of 150mm, and a wall thickness of 8mm. During oil production, when the polished rod 1 moves up and down, the gap between it and the packing 5 gradually increases due to friction. At this time, oil will overflow from the gap between the polished rod 1 and the packing 5 into the oil storage tank 4. The oil entering the oil storage tank 4 will be displayed on the surface of the metering ring 2 as it is immersed in the metering ring 2. When the liquid level reaches 65mm from the metering ring, the oil worker should pay close attention. When the liquid level reaches 130mm from the metering ring, the oil worker can tighten the packing box cover 3 and compact the packing 5, but not too tightly, ensuring that the packing box does not leak. At the same time, collect the oil in the oil storage tank 4 and wipe the metering ring 2 clean. This process does not require stopping the well, and the cycle is repeated.

Claims

1. The wellhead packing box capable of measuring leakage is characterized by: An oil reservoir is added to the top of the conventional packing box, and a metering ring is added to the polished rod.

2. The oil storage tank described in claim 1 is cylindrical, with a hole at the bottom and may be integral with the top of the packing box cover, or may be fixedly and sealed together.

3. The measuring ring described in claim 1 is a measuring ring 3 with a measuring scale on one side, and its material is, but is not limited to, a water-repellent, oil-repellent, corrosion-resistant, brightly colored, and elastic material.

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