Well development techniques

Purposes of studying on discipline: Studying the well development techniques. Tasks of studying on discipline: Students knowledge acquisition on destination and operation principles of equipment for well development.

Well flowing is possible when reservoir energy is large enough to meet the followng condition: General indispensable condition for well flowing Bottom-hole pressure magnitude must be high enough to overcome:  Hydrostatic pressure of fluid in a flow column;  Friction pressure drops in a tube equipment;  Wellhead pressure. Flowing well development Reservoir pressure must be larger than the bottom-hole pressure to produce the well stream

Oil-well artesian flowing (Well flowing, without gas bubble) It is possible when: Well-fluid does not contain the solute gas and the bottom- hole pressure exceeds hydrostatic pressure of fluid in a flow column; Well-fluid contains the solute gas and the well-head pressure exceeds the saturation pressure. Oil-well flowing at the expense of gas energy (Well flowing, with gas bubble) Well flowing may occur when:  Bottom-hole pressure exceeds the saturation pressure (gas is separated in a flow column);  Bottom-hole pressure is lower than saturation pressure (gas is separated in a well bottom zone).

 Clipping of a flow column;  Flow control;  Pressure measuring in a flow line and in an annular space of a well;  Transporting various measuring devices to a bottom hole is one where the flowing occurs at the expense of reservoir energy. Casing head Christmas tree Flow head includes: Casing head, Christmas tree Flowing well Flow head provides the following:

Three-way flow head scheme 1.Christmas tree 2.Casing head; 3.Valve gates; 4.Three-way tee; 5.Bean; 6.Buffer valve gate with a cross-over valve and manometer.

The application advisability of the cross-way flow head scheme is caused by necessity to replace the bean without well shutdown. Cross-way flow head scheme 1.Christmas tree 2.Casing head; 3.Valve gates; 4.Cross tee; 5.Bean; 6.Buffer valve gate with a cross-over valve and manometer

Well devices Well flowing control devices (beans) Operating conditions of flowing wells may vary by: Creation of opposite pressure in a flow line with the help of a well-head bean Creation of local flow resistance in the bottom section of flow column with the help of bottom-hole bean Selection of a diameter and length of a flow column Operating conditions of a flowing well depends on the fluid consumption, which is regulated by the modification of a bean throat

Well-head bean with a demountable bush 1.Flange; 2.Metal gasket; 3.Metal case; 4.Demountable bush; 5.Socket. Such bean is applied in oil wells with large content of mechanical impurities Regulation of the fluid consumption is realized by the modification of a demountable bush throat.

Adjustable well-head bean 1.Demountable nozzle; 2.Needle tip; 3.Metal case; 4.Rod; 5.Post; 6.Handwheel. Such bean is applied in oil wells with low content of mechanical impurities Stepped regulation of the fluid consumption is realized by the modification of a demountable nozzle throat. Stepless regulation of the fluid consumption is realized by the modification of the throat area between a needle tip and nozzle (by rotation of a handwheel )

Mechanical well development techniques are based on the utilization of additional energy: Pump mechanical energy Compressed gas energy Pumping well development Gas-lift well development Mechanical well development techniques are used when the reservoir energy exhausts. Mechanical well development technique application