ЗЭРС

EXTERNAL CASING ATTACHMENTS

Pressure test device PO

The Pressure Test Device is applied for drill string or tubing string pressure testing and
gaging. The device is included into the drill string during well bore preparation to casing
string running in. It is installed at the adjusted depth. After all the necessary elaborations
and flushing a plug is started at the bottomhole. After the drill string volume pumping up to
PO the plug is set into a seat. Drill string pressure testing is performed with gradual pressure
build-up. When the pressure 25,0±2,5 MPa is reached shear bolts are cut off and a bush is
moved against the bottom sub butt thus opening ports in the body.
The produced modification PO2 has a significantly lower hydraulic hammer effect with washout ports opening.

PARAMETER DESCRIPTION	VALUE
PARAMETER DESCRIPTION	PO-NKT 73	PO-NKT В-73	PO.000	PO.102
Drill string nominal diameter RIH with the device, mm	73	73	73; 89	73; 89
Maximum outer diameter of the device, mm	89	93,2	121	105
Drift diameter of the device, mm	30	30	40	30
Maximum internal overpressure, MPa ±10%	30,0
Length of the device fully assembled, mm	830	830	857	911
Device weight, kg, not more	28,3	31,4	59	51
Maximum tensile FORCE¹, kN (tn)	2000 (200)
Washout ports opening pressure² , MPa ±10%	25
Maximum operating temperature³ , °C	100
Connecting threads: (top and bottom) according to GOST R 50864-90 (TU 3668-00-7-1403-00-39-2005)	73 GOST 633	В-73 GOST 633	Z-102	Z-86 (З-83)

1
Calculated value when stresses reach yield point of the material.
2
Actuation pressure with all the shear bolts.
3 Reference only, depends on operating conditions of general mechanical
rubber goods in a well.