Novel rubber packing for oil field pumping wellhead seal

Abstract

The invention discloses novel rubber packing for an oil field pumping wellhead seal. The novel rubber packing comprises a packing body of a cylindrical spiral structure, a polished rod through hole isformed in the middle of the packing body, the packing body is wrapped with one or more fabric layers, and an inner hole is formed in the packing body. The novel rubber packing is simple and ingeniousin structure, and simple in preparation process, the service life of the wellhead seal is greatly prolonged, cleanliness of a wellhead is kept, the operation efficiency is improved, the yield loss isreduced, economic benefits are increased, the labor intensity of oil field employees is relieved, and the labor insurance expenditure of the oil field employees is reduced.

Description

technical field [0001] The invention relates to a polished rod seal for oilfield mechanical oil production wellhead, in particular to a new type of rubber packing for oil pumping wellhead seal. Background technique [0002] The existing wellhead sealing method is mainly through the installation of conical rubber packing in the primary and secondary conical sealing boxes, such as figure 1 , the tapered rubber packing is deformed through the gland, and the elasticity of the rubber is used to seal against the sucker rod reciprocating up and down. Due to the oil pumping process in the oil field, the pressure of the crude oil in the oil pipe can reach hundreds of kilograms. Therefore, the crude oil inside can only be completely sealed under the condition of considerable pressure between the tapered rubber packing and the sucker rod. The high pressure causes relatively large friction on the sports fitting surface, and the heat is generated quickly. The capacity of the friction ...

AI Technical Summary

Problems solved by technology

[0005] 1. After vulcanization, the tapered rubber packing after overall molding and shaping is processed into a spiral shape with a lathe. Since the original reinforcement layer is split by lathe processing, the overall strength and stiffness of the packing are greatly reduced, and the rubber’s resistance The tensile and compressive strengths are very limited, so that when the conical rubber packing reciprocates up and down on the sucker rod, it is prone to fatigue, failure and heat generation due to lack of sufficient rigidity and strength. After 60°C, various physical properties will also drop significantly, which will intensify the damage of conical packing

[0006] 2. The inner hole of the tapered packing is in contact with the sucker rod. The inner hole surface of the existing tapered rubber packing is a rubber surface. Although the rubber material with good heat resistance and wear resistance is selected, for this This kind of workplace still can't solve the problem of long-term durability

[0007] 3. The contact surface between the inner hole of the conical rubber packing and the sucker rod currently used is continuous and relatively large in length. When the wellhead is cut off, the friction surface is likely to have no lubricating oil, resulting in dry grinding. In this case It is more prone to heat generation, resulting in a short service life of the original conical rubber packing, which is likely to cause wellhead leakage

[0008] 4. Domestic oil fields, especially Daqing, Changqing, Yanchang, and Qinghai oil fields are mostly low-permeability oil fields, which mainly rely on a large number of pumping units to ensure production. The original production loss due to frequent replacement of packing is relatively large

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