DEVICE FOR DRAINING OIL-CONTAINING LIQUID WHEN LIFTING PIPE STRING FROM WELL Russian patent published in 2025 - IPC E21B33/08 

FIELD: obtaining oil and gas from wells.

SUBSTANCE: invention relates to oil and gas industry, and is intended for collection of oil-containing liquid when lifting pipe string from well. Device for draining oil-containing liquid when lifting pipe string from well includes housing connected to side branch pipe of casing pipe string, side branch pipe interconnected with delivery line of pump, and filter installed in housing. Housing is made in the form of a shell rigidly and tightly connected inside with a centraliser having the possibility of fixation and attachment to the wellhead flange. Filter is inserted in the annular recess formed by the lower part of the housing and the centralizer. At that, filter is made in the form of filtering rings with holes, diameter of which in each filtering ring decreases from top to bottom by 0.5 mm. At that, the holes themselves are made diverging from top to bottom with angle of 30°. Filter is rigidly fixed in the annular recess of the housing by the lower and upper rows of locking screws. On the lower end of the housing there is a hole connected to the side branch pipe of the casing string by means of a bend. On the upper surface of the centralizer there is a wiper, which is tightly connected to the centralizer and the wellhead flange by means of pins and nuts. Annular inner space above the filter is closed by a cover ensuring filter flushing. Cover is made with holes for attachment to the wellhead flange and has the possibility of tight interaction with the inner surface of the housing along the perimeter by its seal. At the same time the housing below the cover, but above the filter is equipped with a drain branch pipe with a valve.

EFFECT: enlarging functional capabilities of the device, improving operating reliability of the device, reducing labour intensity during operation of the device and excluding oil contamination of the working site, operating equipment and wellhead equipment, as well as the surrounding territory of the well.

1 cl, 5 dwg