Abstract: A molecular spectrophotometric method of high precision and accuracy for determining concentration of oil-derived hydrocarbons in water is described. The method allows to obtain direct measurements of oil mass concentration in a water sample and uses environmentally friendly solvents.

Abstract: A corrosion measuring tool for controlling corrosion in an oil well with a tubing has a hollow cylindrical barrel, a hollow element, an expandable sleeve, at least one coupon for corrosion measurement and an elongated member. The hollow element is located at the upper end of the hollow cylindrical barrel and has a conical upper portion and a cylindrical lower portion. The cylindrical lower portion is slidable within the barrel. The cylindrical lower portion has linkage and sliding retention. An expandable sleeve is located at the upper end of the hollow cylindrical barrel, below the conical upper portion. The sleeve has a fastener. Movement of the hollow element relative to the barrel in a downward direction causes the conical upper portion to expand the expandable sleeve. Movement of the hollow element in an upwardly direction releases the expandable sleeve to separate the fastener from the tubing.

Abstract: Assembly and method for extracting fluids, preferably crude oil, from a drilled well within a geological formation by means of reciprocating pumping with hollow sucker rods. The assembly includes: a) a stationary bottom set that attached to the casing at the desired depth and providing the rod pump anchoring system; b) a reciprocating axial movement rod pump having an anchoring system and a centralizer; c) a centralized hollow rod string extending within the well, which is connected to the mobile member of the pump; d) a hollow polished rod connected to the hollow rod string and linked to a system that imparts the reciprocating axial movement to the pump; e) a production bridge connecting the polished rod to the driving tubing through rotating joints, and f) a rigid head that provides a venting exit of the annular space formed between the string and the casing.

Abstract: Assembly and method for extracting fluids, preferably crude oil, from a drilled well within a geological formation by means of reciprocating pumping with hollow sucker rods. The assembly includes: a) a stationary bottom set attached to the casing at the desired depth and providing the rod pump anchoring system; b) a reciprocating axial movement rod pump having an anchoring system and a centralizer; c) a centralized hollow rod string extending within the well, which is connected to the mobile member of the pump; d) a hollow polished rod connected to the hollow rod string and linked to a system that imparts the reciprocating axial movement to the pump; e) a production bridge connecting the polished rod to the driving tubing through rotating joints, and f) a rigid head that provides a venting exit of the annular space formed between the string and the casing.