Aarvi Encon Interview Questions, Process, and Tips

LEL stands for Lower Explosive Limit. Important gases for gas test prior to hot work in red zone are methane, propane, butane, hydrogen, and acetylene.

• LEL is the minimum concentration of a gas or vapor in air that can ignite and burn

• Gas test is done to ensure that the atmosphere is safe for hot work

• Important gases for gas test include methane, propane, butane, hydrogen, and acetylene

• LEL is expressed as a percentage of ...read more

The complete process of a cross country pipeline project involves planning, design, construction, testing, and commissioning.

• Planning phase: Identify project objectives, route selection, environmental impact assessment.

• Design phase: Engineering design, material selection, pipeline alignment.

• Construction phase: Clearing and grading, trenching, welding and joining, coating and insulation.

• Testing phase: Hydrostatic testin...read more

Various codes and standards are followed for laying pipelines to ensure safety and quality.

• API 1104 - Welding of Pipelines and Related Facilities

• ASME B31.4 - Pipeline Transportation Systems for Liquid Hydrocarbons and Other Liquids

• ASME B31.8 - Gas Transmission and Distribution Piping Systems

• ISO 13623 - Petroleum and Natural Gas Industries - Pipeline Transportation Systems

• DOT Pipeline Safety Regulations - Title 49 CFR P

Hydrotest is a pressure test conducted on pipelines to check for leaks and structural integrity.

• Hydrotest involves filling the pipeline with water and pressurizing it to a specified level.

• The pressure is maintained for a specified duration to check for leaks or any other defects.

• The test also checks the structural integrity of the pipeline by measuring the amount of deformation under pressure.

• The test is usually conduc...read more

Hydrotest is a process of testing the strength and integrity of pressure vessels and pipelines using water pressure.

• The equipment used for hydrotest includes pumps, hoses, valves, and pressure gauges.

• The first step is to fill the vessel or pipeline with water and remove any air pockets.

• The second step is to gradually increase the water pressure to the desired level and hold it for a specified duration.

• During the test, ...read more

The instrument used in joint coating process is a profile gauge. Acceptance criteria for surface roughness is specified in the project specifications.

• Profile gauge is used to measure the surface roughness of the joint coating.

• Acceptance criteria for surface roughness is specified in the project specifications.

• Surface roughness is measured in microns or mils.

• The surface roughness should be within the specified range for

Vent pipe is used to equalize pressure and prevent damage to the casing during drilling and installation of pipelines.

• Vent pipe is installed in the annular space between the carrier pipe and the casing.

• It allows air to escape during installation and equalizes pressure during operation.

• It prevents damage to the casing due to pressure buildup.

• It also allows for monitoring of the annular space for leaks or corrosion.

• Prope...read more

Major defects in welding include porosity, cracks, incomplete fusion, and distortion.

• Porosity: caused by gas entrapment in the weld pool. Can be prevented by proper shielding gas and electrode selection.

• Cracks: caused by high stress or improper cooling. Can be prevented by controlling heat input and using preheat/ post-weld heat treatment.

• Incomplete fusion: caused by insufficient heat or improper technique. Can be prev...read more

WPS, WQT, PQR, and PQT are all related to welding processes and qualifications.

• WPS stands for Welding Procedure Specification and outlines the welding process to be used.

• WQT stands for Welder Qualification Test and is used to qualify a welder's skills.

• PQR stands for Procedure Qualification Record and documents the results of a welding procedure qualification test.

• PQT stands for Performance Qualification Test and is use...read more

Disbondment in cold bend pipe can be checked using visual inspection, ultrasonic testing, and radiography.

• Visual inspection can detect disbondment on the surface of the pipe.

• Ultrasonic testing can detect disbondment in the pipe wall by sending high-frequency sound waves through the pipe and analyzing the reflected waves.

• Radiography can detect disbondment by using X-rays or gamma rays to create an image of the pipe and ...read more