PUMP ROD COLUMN, COUPLING FOR PUMP ROD COLUMN AND METHOD FOR EXTRACTING FLUID FROM WELL, AND PUMP SYSTEM Russian patent published in 2022 - IPC E21B17/01 E21B17/02 E21B17/42 C22C9/06 

FIELD: hydrocarbon production.

SUBSTANCE: pump rod column contains: a pump rod having an end containing a rod with external thread, a valve rod sleeve and a coupling. The sleeve of the valve rod has the first end containing a rod with external thread, and the second end containing a threaded part with internal thread, wherein the sleeve of the valve rod is connected to a downhole pump. The coupling contains a core having the first end, a central section and the second end, wherein each of the first end and the second end has an end face, wherein the first end linearly tapers inwards from the central section to the first end face. A diameter of the first end surface is smaller than a diameter of the second end surface. The coupling is made of a spinodal hardened copper-nickel-tin alloy, which has a sliding friction coefficient from 0.175±10% to less than 0.4 when measured on carbon steel, wherein a threaded hole passes through the entire core from the first end to the second end. The threaded hole at the first end of the coupling is a response to external thread of the valve rod sleeve, and the threaded hole at the second end of the coupling is a response to external thread of the pump rod.

EFFECT: provision of increased internal abrasion resistance.

20 cl, 3 tbl, 9 dwg, 3 ex