Unit 5 Rig construction

Ex.1 Learn the new words.

a round-trip – спуско-подъемные операции	landslide - обвал
a bit - долото	ancillary - вспомогательный
used bit – использованное долото	influx - приток
casing pipe, casing – обсадные трубы	a drilling rig – буровая установка
kelly – ведущая труба	swivel – вертлюг
hexagonal - шестигранный	specifications – технические условия
coring – отбор керна	logging – каротаж
washing fluid – промывочный раствор	curvature - кривизна
drill string – бурильная колонна	hose - шланг
annulus, annular space – затрубное пространство	a conductor string - кондуктор
unstable rock – неустойчивая порода	cementing - цементирование
production casing – колонна обсадных труб

Ex.2 Read and translate the following text using words from exercise 1.

Rig construction

Drilling oil and gas wells consists of a round-trip operations (lowering drill pipe with a bit into a well up to the bottomhole and lifting drill pipe with the used bit out of the hole) and the work of the bit in the bottomhole (destruction of the rock with a bit). These operations are periodically interrupted for running casing pipe into the well to protect the borehole walls from landslides and divide the oil (gas) and water horizons. At the same time, ancillary operations are carried out: coring, preparing washing fluid, logging, measuring curvature of the well, exploring the well in order to obtain oil /gas influx. For all these operations there is used a drilling rig. All rigs have similar drilling equipment, which may differ in specifications.

The upper kelly is hexagonal, in some cases. It passes through the opening of the rotor and goes down into the bottomhole. Upper end of kelly is connected to the swivel. The lower part of the swivel can rotate with the drill string, but its upper part is always fixed. A flexible drilling hose is connected to the fixed part of the swivel, through which washing fluid is pumped.

Passing the kelly and drill string washing fluid enters the bit and rushes into the bottomhole.

Coming out of the bit, the fluid washes bottomhole, picks up particles of drilled rock and raises up through the annular space. Then it goes to the receiving tank. After filtering all particles of the drilled rock settle down, and the washing fluid comes again into the inlet nozzle of a boring pump.

After drilling a deep well (30-600 m), a conductor string is lowered in order to isolate the well from unstable rock or upper strata water and to create a vertical direction of the borehole. After the conductor string is lowered, there takes place cementing. When cement is hardened, drilling starts again.

The bit with diameter smaller than that of the previous casing is put into the well. Then, production casing is put into the well and cemented.