5. Какая цель бурового раствора для ремонта скважины?

WO fluids:

Completion Fluid

• It controls the formation pressure

• It cleans the hole from drilling cuttings

• It is used for carrying gravel pack fluids

• It prevents the formation from being damaged during perforations

Packer Fluid

• It controls the hydrostatic pressure

• It equalizes the casing pressure behind the tubing

• It protects the casing from contacting the fluids produced

• It guarantees hydrostatic pressure on the packer

• It is chemically and physically stable

Killing Fluid

• It impedes the reservoir pressure

• It is compatible with the formation

• It preserves the stability of the well

Characteristics

To the extent possible, the killing fluid shall be:

• Undamaging

• Solids free

• Compatible with any required additives

• Chemically and physically stable

• Noncorrosive

• Not dangerous to handle

• Environment-friendly

• Compatible with the formation and fluids present therein

• Have wide density and viscosity range

• Thermally stable

6. Функции и типы раствора для глушения скважины при ремонтных работах

Clay base mud

Profits

• Low costs

• Readily available

• High suspension capability and solids

carrying capacity

Constraints

• Clay swelling

• Formation plugging

• Water block and emulsion block

• Degradability over time

Polymer base mud

Profits

• Poor solids content

• Low filtrate

• High suspension capability and solids

carrying capacity

Constraints

• Potentially damaging

• Unstable with the temperature

• Water block

• Degradability over time

Oil base mud

Profits

• Thermal stability

• Low filtrate

• High suspension capability and solids

carrying capacity

• Noncorrosive

• Low-damaging filtrate in oil reservoirs

Constraints

• Clogging of formation

• Wettability alteration

• Emulsion block

• Degradability over time

• Polluting

Brines

Profits

• Solids free

• Low costs

• Stable over time within saturation limits

• Does not damage the formation

Constraints

• Limited density

• Low suspension capability and solids carrying capacity

• May cause well control problems in highpermeability formations

Made up brines

Profits

• Solids free

• Wide density range

• Controlled chemical composition

• Does not damage the formation

• Free from bacterial actions

Constraints

• High costs

• May require safety measures

7. Какие будут Ваши действия при прихвате нкт в перманентном пакере.

• Calculating the required tension for the release

_ Calculate the required tension for releasing the anchor from the packer, considering the tbg conditions

_ (Weight in air x buoyancy factor) + Packer release value

+ Friction due to well deviation

• Circulation

_ Recover the BPV

_ Install the tripping pipe equipped with the circulating head

_ Open the SCSSV (if any).

_ Circulate through the circulating valve or through the punchers

_ Control the well

• Releasing the string

_ Loosen the tubing hanger lock down screws

_ Slightly overpull the string

_ Turn the string to the right or release it until free, according to the recommendations of the packer manufacturer

_ Lift the string until the hanger is set on the PTR

_ Set the string on the slips and install the safety clamp.

• Pulling out the completion

_ remove the hanger

_ install a sleeve on the free pin

_ lift the string with the elevator

_ recover the safety clamp

_ pull out and recover all completion tools, controlling the hole fill volumes.

• If the string is not released from the packer

_ Cut the string above the anchor tbg

_ circulate inversely and directly

_ pull out the completion

_ continue with fishing operations

_ the packer can be milled, abandoned or reused, depending on the servicing program

• Continue with the workover program