66. How to do the vent connection in a pipeline that carries liquid?

In a pipeline that carries liquid, we need to vent out the air. In order to do this vent connection, a valve is fitted at the topmost point in a pipeline.

67. What is called a hot load or an operating load and what is a cold load?

It is the weight that the spring needs to support during the operation of the pipeline. The cold load is the weight that the spring needs to support while the pipeline is not operating

68. What are the types of pipe support?

Snubbers (hydraulic and mechanical), sway braces, Rigid or weight support, and Rigid restraints and anchors

69. What is a variable spring support?

These supports would provide varying supporting forces to the pipe when the pipe moves vertically because of the contraction or elongation.

70. What is the need for a constant spring support?

This type of supports is needed when the thermal movements are high, this type of spring supports is required to reduce the load created in the pipeline.

71. Where should we locate the pipe supports?

The pipe support must be located near to the loads such as valves, flanges, etc. So the bending force can be kept to a minimum.

72. How to do the piping stress analysis?

Make sure that the stress in the pipeline cornponents is within the limits. Restrict the problems that are caused by mechanical vibrations such as fluid hammer and pulsation. We must also solve the problems related to the temperature.

73. How to select a flange for the pipeline?

It must be selected according to the type and facing, Pipe size must be considered, Pressure class of the flange must be considered, and it should also be selected according to the pipe schedule and material.

74. What is routing?

The routing is the way in which the pipeline is developed into space, cold pipelines are used to connect static objects like tanks, vessels, etc. The hot are capable to handle the thermal expansion during cold to hot conditions.

75. What is a blind flange?

A blind flange is a flange that doesn't have a and it is used to close the piping system or the vessel opening

76. Explain drip valve?

It is a type of drain valve which is fitted at the driplet bottom in order to do the blow-down

77. What is SIS?

It is the safety instruction sheet which would give the full design details regarding the pipeline.

78. What are the contents of an isometric drawing?

An isometric drawing would have line conditions, construction material, Orientation, piping, and drawing details.

79. What is PIP?

It is the process industry practice, and it would include the details of the requirements for industry practice.

80. What is a blow-down valve?

It is a type of globe valve which can remove sludge from the boiler drums, vessels, driplegs etc.

81. What is a breather valve?

A breather valve is used in a storage tank so that it can release gas or vapor in case of internal pressure.

82. What is a static and dynamic load in a pipeline?

A static load is applied slowly so there would be time to distribute this load. The dynamic load will change quickly with time, so there won't be any time to distribute this load and this would cause pipe movements.

83. What is a plain end?

Plain ends are cut square and reamed to remove burrs and this end is used for mechanical couplings and socket weld fittings

84. Where do we use bevelled ends?

These are used for butt weld applications

85. Explain the straight tee and reducing tee?

The straight tee consist of three openings, two of them have the same axis and the third one will be perpendicular to this axis in order to connect a branch line. The reducing tee is similar to the straight tee and the only difference from the straight tee is that the branch line connection is smaller in size

86. What is the need for a gasket in a valve?

Gaskets can prevent the leakage around the closure mechanism and it can also prevent the leakage of fluid to the atmosphere

87. What are the factors that would affect the pipe span?

Size, schedule, liquid or vapor, insulated or bare pipe

88. How to do the rack design?

First create a line routine diagram then calculate the bent spacing, then set the width of the rack, at last, decide elevations and levels

89. What are the types of temperature measurement instruments?

Thermowells, thermocouples, RTD, and Filled system bimetallic thermometer

90. What are the inferential methods of level measurement?

Hydrostatic head, buoyancy, conductance, radiation, float.

91. What is the need for restriction orifice plates in a pipeline?

It is required for the effective distribution of fluid in a piping network

92. What are the types of direct level measurement?

Dip sticks, gauge glasses, reflex or transparent

93. Name the pressure instruments which is used in chemical industries?

Manometer, bourdon tubes, bellows, and diaphragms

94. What are the types of flow measurement devices?

Rotameter, variable area flowmeter, magnetic flow meter, orifice plate, turbine flow meter, and positive displacement meter.

95. Where do we use butterfly control valves?

Butterfly valves are used for large size piping network and it can handle clean fluids

96. What are the factors that must be considered while routing a pipe underground?

Flange joints must be in I-JIG piping and also avoid the I-JIG routing of the pipe that handles hazardous fluids. The minimum pipe size that is routed underground should not be less than one inch. The buried piping must be protected from corrosion and also freeze protection must be done for outdoor piping.

97. What is a PIG in a pipeline?

It is a device that moves inside a pipeline in order to do the cleaning. It would remove any debris which is left in the line and also it can maintain the line efficiency there are two types of PIG's and they are cleaning pigs and sealing pigs.

98. Describe the process flow diagram?

It is a type of block diagram which shows the unit operation and unit processes. This diagram would show all the major equipment and main piping and its flow.

99. Where should a drain be located?

It must be located at the bottom section of the drum

100. Where should be a temperature instrument be located?

It must be located in liquid space, mostly at the bottom portion of the drum

OIL & GAS CAREER GUIDANCE : INTERVIEW QUESTIONS & ANSWERS - PART 3