10+ Cairn Oil Interview Questions and Answers

The best cleaning methods for pipelines after construction include pigging, chemical cleaning, and water flushing.

• Pigging involves using a device called a 'pig' to remove debris and buildup from the pipeline.

• Chemical cleaning uses specialized chemicals to dissolve and remove contaminants from the pipeline walls.

• Water flushing involves flushing the pipeline with water at high pressure to remove any remaining debris or contaminants.

Impressed Current Cathodic Protection system is better for Road / Railway crossings.

• Impressed Current Cathodic Protection system is more effective in providing continuous protection compared to Galvanic Cathodic Protection system.

• Impressed Current system allows for adjustment of current output to suit changing conditions.

• Regular monitoring and maintenance is required for Impressed Current system to ensure optimal performance.

• Examples of Impressed Current systems include trans...read more

The best type of Circuit Breaker for higher voltages is a Gas-insulated Circuit Breaker (GCB) due to its superior insulation properties and ability to handle high voltages.

• Gas-insulated Circuit Breakers (GCBs) are filled with sulfur hexafluoride gas, which has excellent insulating properties.

• GCBs are compact in size and can handle high voltages up to 1100 kV, making them ideal for high voltage applications.

• They are highly reliable and require minimal maintenance compared to o...read more

Transmission voltages are in multiples of 11kV due to historical reasons and practical considerations.

• Historically, the standardization of transmission voltages around 11kV was influenced by early power system designs and equipment capabilities.

• Practically, using multiples of 11kV allows for easier voltage transformation and compatibility between different parts of the power grid.

• Higher voltages like 132kV, 220kV, and 400kV are commonly used for long-distance transmission to ...read more

A blowout preventer is a safety device used to control and seal off the flow of oil and gas from a well in the event of a blowout.

• Prevents uncontrolled release of oil and gas during drilling operations

• Consists of hydraulic rams and annular preventers

• Activated remotely or by a control panel

• Critical component in offshore drilling operations

• Example: Deepwater Horizon oil spill could have been prevented with a functioning blowout preventer

QA/QC of hydrocarbon's pipeline construction involves ensuring compliance with industry standards and regulations.

• Performing inspections and tests on materials used in construction

• Monitoring welding processes to ensure quality and integrity of welds

• Conducting pressure tests to check for leaks and structural integrity

• Documenting all QA/QC activities and maintaining records for future reference

Switchgear refers to electrical equipment used to control, protect, isolate, and switch electrical circuits. Protection involves measures to prevent damage to electrical equipment and ensure safety.

• Switchgear includes devices like circuit breakers, fuses, and disconnect switches.

• Protection involves measures like overcurrent protection, earth fault protection, and differential protection.

• Switchgear and protection are essential in electrical systems to ensure safe and reliable ...read more

A centrifugal pump works by converting mechanical energy from a motor into kinetic energy in a fluid through the rotation of an impeller.

• Centrifugal force is created by the rotation of the impeller, causing the fluid to move radially outward.

• The kinetic energy of the fluid increases as it moves through the pump, creating pressure that pushes the fluid through the system.

• Common applications include water circulation in HVAC systems, wastewater treatment, and oil refining proce...read more

Sizing a heat exchanger involves calculating the required heat transfer area based on the heat duty and the overall heat transfer coefficient.

• Determine the heat duty or heat load that the heat exchanger needs to handle.

• Calculate the overall heat transfer coefficient based on the type of fluids, flow rates, and materials of construction.

• Use the heat transfer area equation (Q = U*A*ΔTlm) to calculate the required heat transfer area.

• Consider factors such as fouling, pressure dro...read more

Generation, transmission, and distribution of electrical system involves producing electricity, sending it through power lines, and delivering it to consumers.

• Generation: Electricity is produced at power plants using various sources such as coal, natural gas, nuclear, hydro, wind, or solar energy.

• Transmission: High voltage electricity is sent over long distances through transmission lines to substations.

• Distribution: Lower voltage electricity is distributed from substations t...read more

Mock drills are practice exercises while emergencies are real-life situations.

• Mock drills are planned and controlled exercises to test emergency response procedures.

• Emergencies are unexpected and unplanned events that require immediate action.

• Mock drills are conducted to train and familiarize individuals with emergency protocols.

• Emergencies involve real risks and potential harm to people or property.

• Mock drills aim to identify weaknesses in emergency response systems and impr...read more

Chemical process engineering involves designing, optimizing, and operating processes to produce chemicals and materials.

• Involves designing and optimizing chemical processes

• Focuses on efficient production of chemicals and materials

• Requires knowledge of chemistry, physics, and engineering principles

• Involves troubleshooting and improving existing processes

• Examples include designing a new method for producing a specific chemical, optimizing a reactor for better yield

Induction machines are AC motors that work on the principle of electromagnetic induction.

• There are two types of induction machines - single-phase and three-phase

• Single-phase induction machines are used in small appliances like fans and washing machines

• Three-phase induction machines are used in industrial applications like pumps and compressors

• Induction machines work by inducing a magnetic field in the rotor through electromagnetic induction

• The rotor then rotates due to the in...read more

Inspection involves thorough examination and evaluation of products or processes to ensure they meet quality standards.

• Develop a detailed inspection plan outlining what needs to be inspected and how

• Use appropriate tools and techniques to conduct inspections

• Document findings and communicate any issues or defects to relevant stakeholders

• Follow up on corrective actions to ensure issues are resolved

• Regularly review and update inspection procedures to improve effectiveness

Oil water separation is achieved through various methods such as gravity separation, coalescence, flotation, and filtration.

• Gravity separation relies on the difference in density between oil and water to separate them.

• Coalescence involves the use of chemicals or equipment to merge small oil droplets into larger ones for easier separation.

• Flotation uses air bubbles to float oil to the surface for removal.

• Filtration involves passing the mixture through a filter to separate oil ...read more

Chemical reaction engineering is the study of chemical reactions and their design and optimization in industrial processes.

• It involves the application of chemical kinetics, thermodynamics, and transport phenomena to design and optimize chemical reactors.

• Chemical reaction engineering is used in industries such as petrochemicals, pharmaceuticals, and food processing.

• Examples of chemical reactions include combustion, polymerization, and fermentation.

• The goal of chemical reaction...read more