Top 21 Petroleum Engineering Interview Questions You Must Prepare 16.Aug.2022

Dogleg term is used to refer for an abrupt change in direction in the wellbore, resulting in the formation of the keyseat.

Die insert is a hard steel, a serrated piece which is removable and fits into the jaws of the tongs and firmly holds the body of the drill pipe, drill collars while the tongs are making up or breaking out of the pipes.

Kelly bushing is a device fitted to the rotatory table through which the Kelly passes and the mean by which the torque of the rotatory table is trmitted to the Kelly and to the drill stem.

A perforation is a hole made in the casing or liner of an oil well to connect it to the reservoir.

Blowout preventer is installed on the top of the well and is used to control the back pressure produced by oil during the drilling process.

Annular blowout preventer is usually a large valve, installed above the ram preventers, it forms a protective seal in the annular space between the pipes and well bore. It seals the annulus between the Kelly, drill collar and drill pipe.

Lowering a device into the drill hole to measure the pressures, it will reveal whether reservoir rock has been reached.

Induction logs are used in wells that do not use water or mud, but oil-based drilling fluids or air. They are non-conductive and therefore cannot use electric logs instead they use magnetism and electricity to measure resistivity.

The draw down test will help you to estimate the reservoir volume.

A well log is used for graphical representation of any drilling condition or subsurface features that come across while drilling, which is used for the evaluation of the well.

Desander is a centrifugal device used for removing sand from drilling the fluid to avert the abrasion of the pumps. While Desilter is a centrifugal device used to remove the slit or very fine particles.

Hydraulic fracturing is a technique in which tons of gallons of water, chemicals and sand at high pressure is pumped down across the drilled well. This pressurized mixture makes rock layer to crack and make small space or fissure, through which natural gas emits out.

Barium Sulfate or BaSO4 mineral is frequently used to increase the density of drilling mud.

The underbalanced drilling is an alternative way of drilling oil and gas wells, where the pressure in the wellbore is kept lower than the fluid pressure. The advantage of underbalanced drilling is that it reduces formation damage in reservoirs.

  • Resistivity logs
  • Spontaneous potential logs
  • Gamma ray logs
  • Gamma ray absorption logs
  • Neutron logs
  • Sonic porosity logs

A proppant is a solid material, which is treated with sand or ceramic materials. It is used to keep the induced hydraulic fracture open.

Various methods for well test analysis are:

  • Pressure drawdown tests
  • Pressure build up tests
  • Type curve analysis
  • Pulse tests and Interference
  • Drill stem and wireline formation
  • Gas well tests

Spontaneous logs determine the permeability of the rocks in the well by denoting the electrical currents produced between the drilling fluids and formation water held in the pore spaces.

When the oil well is shut-in, there is continue flow of fluid into the wellbore. This flow of fluid is referred as wellbore storage.

Pseudo pressure is a mathematical pressure function which accounts for the variable compressibility and viscosity of gas with respect to pressure.

The drilling muds are used for:

  • Lubrication purpose and for cooling of the drill bit and pipe
  • It removes the cuttings that come from the bottom of the oil well
  • Prevent blowouts by acting as a sealant