List of top Petroleum Production Operations Questions

A four–column semi–submersible floater is located offshore. The diameter of each column is $5~\text{m}$. Consider the total displaced weight of seawater of the semi–submersible as $4000~\text{tonnes}$. Assume added mass contribution as $50\%$ of the semi–submersible weight, and seawater density as $1025~\text{kg/m}^3$. (Acceleration due to gravity $=9.81~\text{m/s}^2$.) The natural period of oscillation of the floater in vertical mode is __________ seconds (rounded to one decimal place).
An empty steel pipeline with massless endcaps has an outer diameter, $D$, and thickness, $t$. The density of steel is $7850\ \mathrm{kg/m^3}$. The critical $D/t$ ratio at which the pipeline starts floating in seawater of density $1025\ \mathrm{kg/m^3}$ is _________ (rounded to two decimal places).

Figure shows an inextensible catenary mooring cable in still water. The submerged weight (per meter length), and the anchor radius are 100 kg/m and 50 m, respectively. If horizontal tension ($T_h$) in the catenary is 1600 kg, the catenary length (AB) is ............. m (rounded to two decimal places). 

Select ALL the safety system(s) that is/are required in an offshore platform.
Which of the following offshore rigs has the HIGHEST water depth of operation?
In a counter current heat exchanger, the hot fluid enters at 175 °F and exits at 100 °F. The cold fluid enters at 75 °F and exits at 85 °F. For the calculation of heat transfer rate, consider the tube surface area (per unit length) to be 0.26 ft²/ft and a tube length of 40 ft. The overall heat transfer coefficient of the exchanger is 100 BTU/hr-ft². The minimum number of tubes required in the exchanger for a heat duty of \( 15 \times 10^5 \) BTU/hr is \(\underline{\hspace{2cm}}\) (round off to nearest integer).

Match the platforms (GROUP I) with appropriate support systems (GROUP II). 
 

Match the suitable artificial lift methods (GROUP I) to meet the requirements (GROUP II) given in the table. 

Heavy oil recovered from reservoirs can be represented by $C_xH_{1.5x}$. Suitable processes to reduce the density of heavy oil are
 

The primary function of the thruster in the Dynamic Positioning System of an offshore installation is
Which ONE of the following offshore installations uses Dynamic Positioning System for station keeping?
Which ONE of the following is NOT a primary safety system for offshore installations?
MOPU (in the context of offshore drilling and production systems) stands for
Select the CORRECT firefighting system for electrical switchgear room in an offshore facility.
A tubing with an inner diameter of 2.259 inch delivers oil from a well at the rate of 1000 bbl/day. The API gravity and viscosity of the oil are 40° and 1.2 cP, respectively. The tubing makes an angle of 15° with the vertical. Assuming a fanning friction factor of 0.006, the pressure-drop over a length of 1000 ft tubing is \(\underline{\hspace{2cm}}\) psi (round off to nearest integer).
Crude oil from oil sands contains bitumen and asphaltene, and this crude is heavy and viscous at room temperature. Assume that one such crude oil is represented by \( C_xH_{1.2x}O_y \). For easier transportation through pipelines, it should be processed further. Identify the processes which help in transportation of this crude oil.
If the specific heat ratio of natural gas is 1.28, the critical pressure ratio (ratio of outlet pressure to upstream pressure) through a choke is \(\underline{\hspace{2cm}}\) (round off to two decimal places).
Oil and gas pipelines, which are at an elevated pressure (about 3 MPa) and sub-ambient temperature (below 298 K), may get blocked by the formation of solid hydrates. One of the strategies adopted to inhibit the formation of hydrates is the injection of Thermodynamic Hydrate Inhibitors (THIs) into the reservoir fluid.
Identify all suitable chemicals that are commonly used as THIs.
Solids that may possibly form in the offshore pipelines during the production of oil and gas from deep-water reservoirs are