30+ ADNOC Interview Questions and Answers

The bypass valve can be replaced by isolating the vessel, depressurizing it, and then replacing the valve.

• Isolate the vessel by closing the inlet and outlet valves

• Depressurize the vessel by venting the gas or liquid

• Remove the old valve and install the new one

• Repressurize the vessel and open the inlet and outlet valves

Concentric reducers have a common centerline while eccentric reducers have an offset centerline.

• Concentric reducers are used in vertical piping systems to prevent accumulation of air pockets.

• Eccentric reducers are used in horizontal piping systems to prevent accumulation of solids or liquids.

• Concentric reducers are symmetrical while eccentric reducers are not.

• Concentric reducers are easier to manufacture and install than eccentric reducers.

Precautions are necessary to ensure safe and efficient plant operation.

• Regular maintenance of equipment and machinery

• Proper training and certification of personnel

• Strict adherence to safety protocols and procedures

• Regular inspections and audits to identify potential hazards

• Effective communication and coordination among team members

• Use of personal protective equipment (PPE) as required

• Emergency response planning and drills

• Proper handling and storage of hazardous materials

• Envir...read more

The carbon percentage in carbon steel varies from 0.05% to 2.0% depending on the grade.

• Carbon steel is an alloy of iron and carbon.

• The amount of carbon in carbon steel determines its strength and hardness.

• Low carbon steel contains less than 0.3% carbon, while high carbon steel contains more than 0.6% carbon.

• Some common grades of carbon steel and their carbon percentage are: A36 (0.26%), 1018 (0.18%), and 1045 (0.45%).

Isolation is the process of separating a system or equipment from its energy source to ensure safety during maintenance or repair.

• Isolation involves disconnecting a system or equipment from its power source, locking it out, and tagging it to prevent accidental re-energization.

• There are two types of isolation: electrical isolation and mechanical isolation.

• Electrical isolation involves disconnecting the electrical supply to the equipment, while mechanical isolation involves blo...read more

Nitrogen purging is done to remove impurities and oxygen from pipelines before commissioning or maintenance work.

• Nitrogen purging is done to create an inert atmosphere inside the pipeline to prevent explosions or fires.

• It is required before commissioning or maintenance work to remove impurities and oxygen from the pipeline.

• Nitrogen purging is also done to prevent corrosion and contamination of the pipeline.

• It is commonly used in the oil and gas industry for pipeline maintenan...read more

There are three types of vibration in the field: axial, radial, and tangential.

• Axial vibration occurs parallel to the axis of rotation.

• Radial vibration occurs perpendicular to the axis of rotation.

• Tangential vibration occurs at a right angle to both axial and radial vibration.

• Vibration analysis is used to detect and diagnose problems in rotating machinery.

• Excessive vibration can lead to premature failure of bearings, gears, and other components.

I have experience working with various pipe materials and standards including carbon steel, stainless steel, and PVC.

• I have worked with carbon steel pipes in a power plant project.

• I have also worked with stainless steel pipes in a pharmaceutical plant project.

• In a water treatment plant project, I have worked with PVC pipes.

• I am familiar with ASME B31.3, API 5L, and ASTM standards for pipe materials and welding procedures.

Reinforcement fittings are used to strengthen and support piping systems.

• Common reinforcement fittings include tees, elbows, reducers, and couplings.

• Telescoping fittings are used to adjust the length of piping systems.

• Flange fittings are used to connect pipes to other equipment or structures.

• Saddles are used to support piping systems on walls or ceilings.

• Reinforcement fittings can be made of various materials, including steel, copper, and PVC.

• Proper installation of reinforcem...read more

Yes, I am familiar with preventive maintenance jobs.

• Preventive maintenance involves regularly scheduled inspections, cleaning, and repairs to prevent equipment breakdowns.

• I have experience performing preventive maintenance on various types of instrumentation equipment, such as calibrators, transmitters, and controllers.

• Examples of preventive maintenance tasks I have performed include checking for leaks, replacing worn parts, and testing equipment performance.

• I understand the ...read more

Pipes are used to transport fluids and gases, while tubes are used for structural purposes.

• Pipes have a standardized outer diameter and wall thickness, while tubes have a standardized inner diameter and wall thickness.

• Pipes are typically round, while tubes can be round, square, or rectangular.

• Pipes are often used in plumbing and HVAC systems, while tubes are used in construction and engineering applications.

• Pipes are usually measured by their inside diameter, while tubes are ...read more

Permit to work is a formal written system used to control high-risk activities.

• It is a document that outlines the work to be done and the hazards associated with it.

• It is used to ensure that all necessary safety precautions are taken before work begins.

• It is issued by a competent authority and must be signed by all parties involved in the work.

• Examples include hot work permits, confined space permits, and excavation permits.

The qualification for an Instrumentation Technician typically includes a degree or diploma in instrumentation technology or a related field.

• A degree or diploma in instrumentation technology or a related field is usually required.

• Knowledge of electrical and electronic systems is important.

• Experience with calibration and troubleshooting of instruments is often necessary.

• Familiarity with industry standards and regulations is beneficial.

• Strong analytical and problem-solving skill...read more

Thermocouple range refers to the temperature range within which a thermocouple can accurately measure temperature.

• Thermocouple range varies depending on the type of thermocouple used.

• Common thermocouple types include J, K, T, E, and N.

• For example, a type K thermocouple has a range of -200 to 1350 degrees Celsius.

• It is important to select the appropriate thermocouple type for the temperature range being measured.

An anti-surge valve is a control valve used in a compressor system to prevent surge and maintain stable operation.

• An anti-surge valve is typically installed in the discharge line of a compressor.

• It is designed to protect the compressor from surge, which is a phenomenon of unstable flow and pressure that can cause damage to the compressor.

• The valve opens or closes based on the compressor's operating conditions to maintain a safe flow rate and prevent surge.

• It works in conjunct...read more

Elbow lets change the direction of flow in piping system.

• Elbows are used to change the direction of flow in a piping system.

• They come in different angles such as 45°, 90° and 180°.

• They are available in different materials such as PVC, copper, steel, etc.

• Elbows can be welded or threaded onto the piping system.

• They are commonly used in plumbing, HVAC, and industrial piping systems.

The first step to involve in a safe working procedure is to assess the risks and hazards associated with the task.

• Conduct a thorough risk assessment before starting any task

• Identify potential hazards and evaluate their severity and likelihood

• Implement appropriate control measures to mitigate the risks

• Ensure all necessary safety equipment and procedures are in place

• Provide adequate training and supervision to workers

• Regularly review and update the safe working procedure

Positive isolation is the process of completely isolating a section of piping or equipment from the rest of the system to perform maintenance or repairs.

• Identify the section of piping or equipment that needs to be isolated

• Close all valves and block all lines leading to and from the section

• Use blind flanges or spectacle blinds to physically block the section

• Ensure that the isolation is secure and pressure tested before beginning work

• Remove the isolation once work is complete a...read more

Yes, I have experience working with gas turbines.

• I have worked with gas turbines in my previous job as an instrumentation technician.

• I am familiar with the maintenance and troubleshooting of gas turbines.

• I have experience in calibrating and testing gas turbine sensors and instruments.

• I have knowledge of the safety protocols and regulations related to gas turbines.

Positive isolation is the process of completely isolating a section of a system to prevent any flow or transfer of material.

• Positive isolation is achieved by using valves, blinds, or other physical barriers to completely block the flow of material.

• It is important for safety and maintenance purposes, as it allows workers to safely perform tasks without the risk of exposure to hazardous materials.

• Examples of positive isolation include isolating a section of a pipeline for maint...read more

Speed conversion calculation in belt drive from driver to driven.

• Determine the speed ratio between the driver and driven pulleys

• Use the formula: Speed of driven pulley = Speed of driver pulley x (diameter of driver pulley / diameter of driven pulley)

• Ensure that the units of measurement are consistent

• Consider the effect of slip in the belt drive system

Metals such as stainless steel, carbon steel, and aluminum are commonly used before the welding process.

• Stainless steel is often used for its corrosion resistance and durability.

• Carbon steel is commonly used for its strength and affordability.

• Aluminum is lightweight and has good conductivity, making it suitable for certain applications.

Dimensions of the elbow of unknown degree are calculated using trigonometry and geometry.

• Calculate the centerline radius of the elbow.

• Use trigonometry to find the length of the elbow.

• Consider the angle of the elbow to determine the dimensions.

• Measure the outside diameter and wall thickness of the pipe for accurate calculations.

The three main things in a hydrotest test pack are pressure gauges, test pumps, and test plugs.

• Pressure gauges are used to measure the pressure during the hydrotest.

• Test pumps are used to generate the required pressure for the test.

• Test plugs are used to seal off the openings in the system being tested.

Safety is the practice of preventing accidents, injuries, and harm to people, property, and the environment.

• Safety involves identifying and assessing potential hazards and risks.

• It includes implementing measures to control and mitigate those hazards.

• Safety also involves educating and training individuals on safe practices.

• Regular inspections and audits are conducted to ensure compliance with safety standards.

• Emergency preparedness and response plans are developed to handle un...read more

The pipe is injected with argon gas before welding to create an inert atmosphere.

• Before welding, the pipe is purged with argon gas to remove any oxygen and moisture that could contaminate the weld.

• This is typically done using a purge gas system that fills the pipe with argon and then vents it out before welding.

• Purging with argon helps prevent oxidation and ensures a clean, strong weld.

• Proper purging techniques are essential for high-quality welds in stainless steel and other...read more

Confined space hazards include hazardous atmospheres. Precautions include proper ventilation and monitoring.

• Confined spaces can have hazardous atmospheres due to lack of oxygen, presence of toxic gases, or flammable substances.

• Precautions include testing the atmosphere before entry, ensuring proper ventilation, and using personal protective equipment.

• Examples of hazardous atmospheres include spaces with high levels of carbon monoxide, hydrogen sulfide, or combustible dust.

• Pro...read more

Wind speed precautions and hazard control for lifting materials

• Check weather conditions before lifting materials

• Monitor wind speed and gusts regularly

• Establish safe wind speed limits for lifting operations

• Use wind speed measuring devices or anemometers

• Secure materials properly to prevent them from being blown away

• Consider using cranes or other lifting equipment with wind load charts

• Train workers on wind speed hazards and safe lifting practices

• Implement a system for communicat...read more

Safe working practices refer to the set of guidelines and procedures that ensure the safety of workers and prevent accidents or injuries.

• Safe working practices involve following safety protocols and procedures

• Workers should be trained on safety measures and use appropriate personal protective equipment (PPE)

• Regular inspections and maintenance of equipment and machinery are necessary

• Proper communication and coordination among team members is essential

• Examples include wearing s...read more

Cement coating standards ensure the quality and durability of cross country pipelines.

• Cement coating standards specify the thickness and composition of the coating.

• Standards also define the application and curing processes for the coating.

• Coating standards ensure protection against corrosion and mechanical damage.

• Examples of cement coating standards include API RP 5L2 and ISO 21809-1.

Bearings are used to reduce friction between two moving parts. There are several types of bearings.

• Plain bearings: sliding contact between two surfaces

• Rolling element bearings: balls or rollers between two surfaces

• Jewel bearings: used in watches and clocks

• Fluid bearings: use a fluid to reduce friction

• Magnetic bearings: use magnetic fields to levitate the shaft

• Tapered roller bearings: used in automotive and industrial applications

• Thrust bearings: used to support axial loads

• Sph...read more

Fairness is the principle of treating individuals equitably and impartially.

• Fairness involves treating all individuals equally and without bias.

• It means providing equal opportunities and access to resources.

• Fairness requires making decisions based on objective criteria and avoiding favoritism.

• Examples of fairness include implementing fair hiring practices, distributing rewards based on merit, and ensuring equal treatment for all employees.

• Fairness also involves considering th...read more

Safety precautions and responsibilities of a safety officer at the worksite.

• Identifying and assessing potential hazards in the workplace

• Developing and implementing safety policies and procedures

• Conducting regular safety inspections and audits

• Providing safety training and education to employees

• Investigating accidents and incidents, and implementing corrective actions

• Ensuring compliance with safety regulations and standards

• Maintaining safety records and documentation

• Promoting a...read more

Safety in offshore working is crucial to prevent accidents and ensure the well-being of workers.

• Offshore working involves unique hazards such as harsh weather conditions, limited access to medical facilities, and potential for equipment failure.

• Strict adherence to safety protocols, including wearing appropriate personal protective equipment (PPE) and undergoing regular safety training, is essential.

• Emergency response plans should be in place, including evacuation procedures a...read more

A near miss is an incident that could have resulted in an injury, illness, or damage, but fortunately, no harm occurred.

• A near miss is a close call or a narrowly avoided accident.

• It is an unplanned event that has the potential to cause harm.

• Near misses are valuable opportunities to identify hazards and improve safety measures.

• Examples of near misses include a worker slipping but catching themselves before falling, a vehicle narrowly avoiding a collision, or a piece of equipme...read more

In case of an emergency, I would remain calm, assess the situation, and take appropriate action to ensure the safety of all individuals involved.

• Remain calm and assess the situation quickly

• Follow emergency protocols and procedures

• Ensure the safety of all individuals involved

• Contact emergency services if necessary

• Provide first aid or medical assistance if trained to do so