SU643618A1 - Device for building up load on bit at drilling holes - Google Patents

Description

Connect it with a thread to connect to a bit or a downhole motor, and in the upper part of the shaft there is a thread for connection to the drill pipes.

The differential valve 8 with seals 11, 12 and 13 of different diameter forms with the shaft 1 three chambers (see FIG. 3), of which one by channels a, biv communicates the internal cavity of shaft 1 with the working cavity of hydraulic box 7, the second channels c c d communicates the cavity under the upper piston 3 with the annular space. And the third channel e communicates with the inner cavity of the slide 3.4. The spool 14, filled in the form of a piston with a thrust, mechanically interacting with the housing 4, is constantly connected by a channel with the internal cavity of the shaft 1.

The creation of a load on the bit during the drilling of a well with the proposed device is carried out as follows.

When transporting the device to the Borehole, the body 4 is in an extremely low position, and the spools 5.8 and 14 occupy the position shown in FIG. 3 and 5. In this position of the spools, the flushing fluid from the pumps enters through channels B, $ and a into the working piston cavity of housing 4. Simultaneously, through channels G, 3 and e, the liquid flows under pressure into the lower chamber of the differential spool 8 and holds it in position The pressure differential acts on the hydraulic core 1, extending its pads, which adhere to the walls of the well. The pressure drop simultaneously affects the lower piston 2 of the shaft 1, which, moving, creates a load on the bit. The reaction from the axial load is transmitted through the pads of the hydraulic core 7 to the walls of the well. Thus, the well is drilled.

until the working stroke of the device ends. At the end of the working stroke of the device (see Fig. 2), the mt of spool 14 rests on the lower end of the nipple 9 and moves it, closing the channel, together with the channel and the annular space

Under the action of the pressure drop and beyond the set of differences in the working areas, the valve 8 moves to the lower position (see Fig. 2) and communicates the internal cavity of the housing 4 through channel b with the annular space. At the same time, the channels of the VIG communicate, and the liquid enters the upper cavity of the housing 4 f by moving the valve 5 to the lower position (see Fig.4), as a result of which the channel and overlaps.

Under the action of the pressure drop in the upper cavity of the housing 4, it moves down relative to the shaft i by the amount of travel of the device. Thus, an automatic reboot of the device occurs, after which the cycle of its operation is repeated.

Claims (1)

Invention Formula A device for creating a load on the bit during drilling of wells, including a housing, in al, along a line, communicates with the internal cavity of the drill pipe and interacts mechanically with the housing and the shaft, as well as the hydraulic measles with the working cavity, , .4TOj in order to increase its working capacity, it is equipped with an additional multi-chamber differential spool, the first of which chambers communicate with the internal cavity of the drill pipe and with the working cavity of the core, the second with the working cavity of the core and with the annulus a nd, and the third - the inner space of the first spool. needles .five 9ig.6