THROTTLING DEVICE Russian patent published in 2019 - IPC E21B34/16 F16K15/06 

FIELD: oil and gas industry.

SUBSTANCE: device relates to oil and gas industry and is intended for operation of flowing wells in conditions of availability of hydrates and mechanical impurities. Device is installed on well in production tree and consists of hollow housing with intake and discharge chambers, connected to each other through nozzle, rod for cleaning of axial channel of union, spring-loaded piston with end valve, mounting seat for it and spring-loaded rod. Union is immovably installed in the throttle washer fixed in the axial channel of the hollow housing and separating the intake and discharge chambers. Piston is equipped with internal boring under end valve connected by bypass holes with discharge chamber. Rod is made stepped and is installed with smaller diameter in axial channel of nozzle with formation of annular channel. Larger diameter of rod is equipped with thread for connection with piston and comprises chamber hydraulically connected with annular channel of nozzle by bypass holes. Axial channel of the hollow housing is covered from above with an upper plug containing a feed branch pipe with a plug and a container in the form of a tube with a support nut on the lower end. On the inner surface of the support nut there is a seat and an end valve connected to the rod pressed by the spring through the adjusting nut is installed. Rod body is provided with bore connected by drain hole with cavity under end valve. Thread on the stepped rod is made with possibility of formation of a movable connection to the internal surface of the union in the upper position of the piston. Axial channel of hollow housing is isolated from below by bottom plug equipped with mounting seat for piston end valve and spring-loaded rod, passed inside axial channel of hollow housing and rigidly connected with piston. Container through feed branch pipe is filled with working fluid, for example hydrate inhibitor.

EFFECT: technical result consists in enabling cleaning of annular channel of nozzle by mechanical action on layer of deposits.

1 cl, 2 dwg