Threaded joint for steel pipes and process for the surface treatment thereof
    108.
    发明申请
    Threaded joint for steel pipes and process for the surface treatment thereof 审中-公开
    钢管螺纹接头及其表面处理工艺

    公开(公告)号:US20040195826A1

    公开(公告)日:2004-10-07

    申请号:US10829292

    申请日:2004-04-22

    Inventor: Kunio Goto

    Abstract: This invention relates to a threaded joint for steel pipes which comprises a pin and a box each having a contact surface including a threaded portion and an unthreaded metal contact portion and which can be prevented from galling during repeated fastening and loosening without application of a compound grease. A solid lubricant coating which comprises a lubricating powder such as molybdenum disulfide and a resin binder is formed on the contact surface of at least one of the pin and the box. The coating is formed by applying a coating fluid and drying the applied coating by first stage heating in the temperature range of from 70null C. to 150null C. and second stage heating in the range of from higher than 150null C. to 380null C. The resulting solid lubricant coating has a hardness of 70-140 on the Rockwell M scale and an adhesive strength of at least 500 N/m as determined by the SAICAS (Surface And Interfacial Cutting Analysis System) method, and it exhibits excellent galling resistance even in the environment of high-temperature oil wells. Inclusion of ultraviolet screening fine particles such as titanium oxide fine particles in the solid lubricant coating increases the rust preventing properties of the threaded joint.

    Abstract translation: 本发明涉及一种用于钢管的螺纹接头,其包括销和箱体,每个销和箱都具有包括螺纹部分和无螺纹金属接触部分的接触表面,并且可以防止在反复紧固和松动期间不产生磨损而不施加复合润滑脂 。 在销和盒中的至少一个的接触表面上形成包含润滑粉末如二硫化钼和树脂粘合剂的固体润滑剂涂层。 通过施加涂布液并通过在70℃至150℃的温度范围内的第一阶段加热来干燥所涂覆的涂层并且在高于150℃至380℃的范围内进行第二阶段加热来形成涂层 ℃。所得固体润滑剂涂层在洛氏硬度计上具有70-140的硬度,并且通过SAICAS(表面和界面切割分析系统)方法确定的至少500N / m的粘合强度,并且显示出优异的 即使在高温油井的环境中也具有耐磨性。 在固体润滑剂涂层中包含紫外线屏蔽细颗粒如氧化钛微粒增加螺纹接头的防锈性能。

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