8. Расскажите о преимуществах и недостатках соленных растворах при ремонте

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

9. Применение, преимущество и недостатки коррозионного каротажа

• Applications:

_Producing wells corrosion detection

_Injector wells corrosion detection

_Casing integrity measurement

_Before and after a Frac job

_Casing integrity measurement prior

to sidetrack operation

_Drilling induced “Casing Wear”

evaluation

• Features and benefits:

_System approach to corrosion

evaluation

_High resolution integrity

measurement

_Real-Time or Memory mode

_Compatible with Warrior™ Data

Acquisition System

_Customizable to client surface

acquisition system

_Works on proprietary PTX telemetry

system

10. Функции и применение пакера

Production Packers

Purposes

• Protect the casing from reservoir

fluids and pressures

• Separation of zones to avoid

crossflow

• Subsurface pressure and fluid

control

• Artificial lift efficiency – gas lift

Components

• Seal assembly

• Slips

• Cone assembly

• Friction element

_Not on permanent or

hydraulic set units

• Setting and releasing

mechanism

_Not on permanent units

• Mandrel assembly

• Control head or bypass

Retrievable Packers

• Can act as a bridge plug prior to production

• Connect to tubing via On/Off tool with blanking plug

• Tubing can be landed in tension, compression or neutral

• Slips above and below the elements

• Triple element pack off system

• Pressure up to 10,000 psi

• Fluid bypass needed for pressure equalization

• Retrieved on tubing

• Secondary shear release needed

11. Преимущество и недостатки раствора на нефтяной основе при ремонтных работах.

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

12. Опишите функции и применение фонтанной арматуры

Function of the Wellhead System

• Allow suspension of casing and tubing in the well

• Allow installation of surface barrier

_BOP stack whilst drilling

_X-mas Tree for production/injection

• Allow hydraulic accesses to annuli between tubular systems

Wellhead Types

• Conventional spooled wellhead

_Most common

_Studded flanges or C-clamp make-up

• Compact spools

_Used primarily where available height or makeup procedures are issued

• Mud Line Suspension System

_Split locations of main wellhead functions

• Subsea wellheads

_Complex, remote installation, high cost

Critical areas of the wellhead system

• Seal surfaces and seal system – rings, gaskets etc.

• Landing shoulders

• Flanges faces and ring recesses

Compact Spool Type Wellhead

• Benefits

_Less height

_Minimal stack manipulation – drill and case last 2 casing strings and suspend production tubing

• Problems

_Less flexible

_Internal sealing is more complex