Novel self-lubricating iron-based coatings coupling preparation process

Abstract

The invention relates to a preparation technique of a novel self-lubricating iron-based coating coupling. The preparation technique consists of the following steps: 1. the preparation of the iron-based spraying and welding coating adopts iron-based self-fusible alloy powder as the material, and an iron-based alloy coating is prepared on a general coupling surface via the spraying and re-fusion techniques; 2. the sprayed and welded coupling surface is polished to make sure that the width of the coating surface ranges from 0.25mm- 0.60mm and the roughness is no more than Ra0.8Mum; 3. sulfurization of low temperature ion on the surface: the ion undertakes the spraying and coupling process in a low temperature ion sulfurization oven with a voltage of 800-1000 volt, an atmospheric pressure of 20-50Pa and a temperature of about 300 DEG C for about eight hours. A protective layer of the butter is smeared on the coupling surface to prevent the oxidation of the surface. The preparation technique is characterized by low cost and easy operation. And the self-lubricating iron-based alloy spraying and welding oil-sucker rod coupling acquired from the preparation technique has better wear resistance and self-lubrication quality, with a long service life.

Description

technical field [0001] The invention relates to a preparation process of a novel self-lubricating iron-based coating coupling. Background technique [0002] At present, in oil fields with mild corrosive environment, as the depth of oil wells continues to increase, couplings are facing more and more serious wear problems. Under such conditions, ordinary couplings treated with surface technology can better adapt to the environment of oil wells due to their greatly improved wear resistance. Among them, the surface spray welding iron-based self-fluxing alloy coating is easy to operate, and can also greatly improve the wear resistance of ordinary couplings, and prolong the service life of couplings to a certain extent. However, there are still problems with the use of pure iron-based spray welding coatings, especially in oil wells with severe eccentric wear. Due to the dry friction of the coupling / tubing, the wear resistance of the coupling still cannot meet the requirements, an...

AI Technical Summary

Problems solved by technology

However, there are still problems with the use of pure iron-based spray welding coatings, especially in oil wells with severe eccentric wear. Due to the dry friction of the coupling / tubing, the wear resistance of the coupling still cannot meet the requirements, and the high The hard iron-based coating is easy to scratch the inner wall of the oil pipe

[0003] In view of the above problems, there are generally two ways to solve them: one is to replace the iron-based coating with nickel-based self-fluxing alloy spray-welded coating collars, but the cost of nickel-based coatings is much higher than that of iron-based coatings, resulting in The cost pressure is greater; the second is to add a certain proportion of solid lubricants to the iron-based coating, such as MoS 2 or graphite, etc., but due to the relatively high temperature generated during the coating remelting process, the MoS 2 Decomposition occurs, and graphite will also form pores in the coating during the process, which not only affects its self-lubricating performance, but also increases the porosity of the iron-based coating, which is not conducive to the performance of the coating