公开(公告)号：US5645896A

公开(公告)日：1997-07-08

申请号：US588141

申请日：1996-01-18

Applicant: Robert A.R. Mills

Inventor： Robert A.R. Mills

IPC: F04C2/107 ,  C23C4/10

CPC classification number: F04C2/1075 ,  F04C2230/00 ,  F04C2230/91 ,  F05C2201/0406 ,  F05C2201/0409 ,  F05C2201/0433 ,  F05C2203/0813 ,  F05C2203/0821 ,  F05C2203/0826 ,  Y10T428/12576 ,  Y10T428/31678

Abstract: A hardfacing for downhole progressing cavity pumps is disclosed as well as a method for producing same. The hardfacing consists of a metal carbide layer applied to the ferrous pump rotor body by way of plasma spraying and a top layer of metallic material having a lower hardness than the metal carbide. The metal carbide layer has a grainy surface with a plurality of peaks and intermediate depressions, the peaks being formed by metal carbide grains at the surface of the metal carbide layer. The thickness of the top layer is adjusted such that the depressions between the peaks of the metal carbide layer are completely filled thereby providing the rotor with a metal carbide hardfacing of significantly reduced surface roughness. In the process of the invention, the pump rotor, which may be provided with a molybdenum bonding layer, is plasma coated with the metal carbide and the resulting carbide layer is covered with the metallic material top layer. The top layer is polished either until the dimensions thereof are within the tolerances acceptable for the finished rotor or until a majority of the peaks of the carbide layer are exposed. The hardfacing significantly increases the service life of the rotor and stator of downhole progressing cavity pumps.

Abstract translation: 公开了一种用于井下前进腔泵的硬化面及其制造方法。 表面硬化由通过等离子喷涂施加到铁水泵转子体上的金属碳化物层和具有比金属碳化物低的硬度的金属材料顶层组成。 金属碳化物层具有多个峰和中间凹陷的颗粒状表面，该峰由金属碳化物层表面的金属碳化物颗粒形成。 调整顶层的厚度，使得金属碳化物层的峰之间的凹陷被完全填充，从而为转子提供显着降低的表面粗糙度的金属碳化物表面硬化。 在本发明的方法中，可以设置有钼粘合层的泵转子被等离子体涂覆有金属碳化物，并且所得到的碳化物层被金属材料顶层覆盖。 抛光顶层，直到其尺寸在成品转子可接受的公差内，或直到碳化物层的大部分峰暴露。 表面硬化显着增加了井下前进腔泵的转子和定子的使用寿命。

公开(公告)号：US20100126878A1

公开(公告)日：2010-05-27

申请号：US12325808

申请日：2008-12-01

Applicant: Jovica Marjanovic ,  James Coulas ,  Robert A.R. Mills

Inventor： Jovica Marjanovic ,  James Coulas ,  Robert A.R. Mills

IPC: C25F3/06

CPC classification number: C25F5/00

Abstract: A method for stripping a fused thermal spray metal coating from the surface of a soft metallic substrate. The steps for the method include: immersing the coated metallic substrate in an aqueous solution of chromic acid, peroxide, and a second acid; immersing a metal cathode in the aqueous solution; applying a positive potential to the fused spray metal coated substrate and a negative potential to the metal cathode to generate a direct current between the substrate and the cathode; where the current is applied for a sufficient time to remove the coating. This method permits the electrochemical removal of fused and impermeable thermal spray metal coatings.

Abstract translation: 一种用于从软金属基材的表面剥离熔融热喷涂金属涂层的方法。 该方法的步骤包括：将涂覆的金属基材浸入铬酸，过氧化物和第二酸的水溶液中; 将金属阴极浸入水溶液中; 对熔融的喷涂金属涂覆的基底施加正电势，并向金属阴极施加负电位以在衬底和阴极之间产生直流电; 其中电流被施加足够的时间以去除涂层。 该方法允许电化学去除熔喷和不可渗透的热喷涂金属涂层。