HYDRAULIC FRACTURING

Collar for collar cementing for hydraulic fracturing MMC-G

Collar for Collar Cementing is applied for liner collar cementing with assembly for multistage hydraulic fracturing with isolation of horizontal sector into zones with hydro-mechanical packers.
While using an MMC-G-type collar the following process operations are performed:

washing and washing ports opening through internal overpressure build-up after isolation
of tube space from outer annular space;
washing with ball-drop;
cementing ports opening when a ball is set into a collar seat;
casing cementing with starting of a cementing plug after pumping in cement slurry;
displacing of cement slurry to the outer casing annular space until receiving the “bump”
signal;
collar ports closing by the internal overpressure build-up.

PARAMETER DESCRIPTION	VALUE
PARAMETER DESCRIPTION	MMC-G 102	MMC-G114
Casing string nominal diameter RIH with the coll	102	114
Open borehole nominal diameter (bit diameter) which the collar is run in, mm	124	142,9
Maximum outer diameter, mm	118	133
Drift diameter, mm	88	98
Values of controlling overpressure for devices actuation¹ , MPa: - circulation ports opening; - cementing ports opening; - cementing ports closing	16,0 11,0 5,0
Maximum operating temperature² , °C	100
Maximum internal overpressure on the collar body³ , MPa	70,0
Maximum external overpressure on the collar body³ , MPa	70,0
Maximum tensile force³ , kN	600 (60)
Length, mm	1715	1121
Weight, kg	58,4	47,9
Connecting threads according to TU 14-161-163-96	ОТТМ 102	ОТТМ 114

1
Controlling overpressure values are given when all the shear bolts on the unit are used.
2
Reference only, depends on operating conditions of general mechanical rubber goods in a well.
3
Calculated value when stresses reach yield point of the material.