1,Application:
Used in conjunction with hydraulic control system,
the annual BOP seals off the annulus of different sizes when pipes are in use in
the hole. An annular BOP can also seal off the hole when no pipe is in it. When
used in conjunction with the pressure-regulating valve and accumulator, the
annular BOP allows snubbing service.
2,Working
Principles:
A hydraulic control system is used to close or open the
annular preventer. When it is closed, high pressure oil is directed to the
closing chamber positioned in the lower side of the piston, causing the piston
to move upward. The packing unit is compressed by the moving piston. Because the
annular BOP has a cap, the packing unit can not move upward an only can move
toward the center of the well to pack off a string or seal off the well.
3, Operating Requirements:
A, The annular BOP can be used to
seal off a well where the drill pipe is in use if the well blows out. However,
the annular BOP cannot be closed for a long time, because the packing unit is
easy to be damaged and the BOP itself has no lacking mechanism.
B,It is
necessary to use a drilling tool with 18°bevel when running/retrieving drill of
operation with BOP, running/retrieving drill should be slow pass through the
nipple and all the rubber protecting collar on the drilling tool should be
discharged off.
C,With the annular BOP in the closed position and shut-in
pressure kept below 5MPa,the string can be moved either up or down, but mustn't
be rotated.
D, It is forbidden to open the annular BOP to relieve the
pressure out of the well to avoid rubber core damage.
E, Be sure to check
whether the annular BOP is in the full open position or not every time after
opened in order to prevent damage to the packing unit.
F, Clean the inside of
the BOP after well cementing operation is completed in order to keep its
closings and openings flexible.
G, More attention shall be paid to ring
gaskets and gasket grooves during installation of the BOP or its removal from
the service.
H, After entering the destination layer, running/retrieving
drill once should be accompanied with test of well enclosed with drilling tool
once, and inspect the effect of well enclosed with rubber core, if beyond the
requirement, it should be replaced.
I, Periodically perform pressure test on
the annular BOP in accordance with applicable standards.
1. Cap 2.Packing
Unit
3.Support Ring 4.Piston 5.Body
4. Tapered
Rubber Annular BOP
1,Upper housing and the body have two
connection forms as connection by bolts and connection by claw chuck.
2,Annular BOP with tapered rubber is composed of seven parts as upper
housing, wear plate, body, piston, tapered rubber, anti-dust ring supporting
cylinder.
3,The dynamic seal of annular BOP adopts the sealing ring of lip
structure, which reduces the wearing of sealing ring to maximum, and the sealing
is reliable; the rubber is not easy to fold back, and there is the effect of
funnel; and the well pressure has the function of assisting sealing, etc.
5. Spherical
Rubber Annular BOP
1,Upper housing and the body have two
connection forms as connection by bolts and connection by claw chuck.
2,Annular BOP with tapered rubber is composed of five parts as upper
housing, body, piston, spherical rubber and anti-dust ring.
3,The dynamic
seal of annular BOP adopts the sealing ring of lip structure, which reduces the
wearing of sealing ring to the maximum, and the sealing is reliable; the rubber
is not easy to fold back, and there is the effect of funnel; and the well
pressure has the function of assisting sealing , etc.
6. Specifications And Technical Parameters Of Model A Annular BOP
Model | (mm) Bore | (Mpa/psi) Working pressure | Dimensions(mm) | Opening oil volume | Closing oil volume | |
FHZ18-70 | 179.4 | 70/10000 | 1200 | 1250 | 27 | 36 |
2FHZ28-70 | 279.4 | 70/10000 | 1465 | 1653 | 66 | 67 |
FHZ35-70 | 346.1 | 70/10000 | 1554 | 1742 | 117 | 116 |
FHZ43-35 | 425.4 | 35/5000 | 1680 | 1590 | 134 | 134 |
FHZ54-14 | 539.7 | 14/2000 | 1380 | 1437 | 94.5 | 95.3 |
