Pip4AE3 U7 C1 Review

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What is the primary consideration when selecting materials for pipe manufacturing?

Weight of the material

Appearance of the material

Operating conditions of the piping system (correct)

Cost of the material

Which ASME code addresses Power Piping and Process Piping?

B31.4

B31.3

B31.2

B31.1 (correct)

What type of iron is used for screwed fittings?

Forged steel

Gray cast iron

White cast iron

Malleable iron (correct)

What is the primary advantage of using cast iron in piping systems?

High resistance to corrosion and abrasion Signup and view all the answers

What type of material is commonly used for instrumentation and water services in power plants?

Brass or Copper Signup and view all the answers

What is the main difference between seamless and welded steel pipes?

Seamless pipes are manufactured without joints, while welded pipes are manufactured with joints Signup and view all the answers

What is the purpose of the nominal pipe size?

To provide an approximate indication of pipe diameter Signup and view all the answers

What is the difference between NPS and DN?

NPS is in inches and DN is in millimeters Signup and view all the answers

What does the number represent for NPS 14 (DN 350) and larger pipe?

Actual outside diameter of the pipe Signup and view all the answers

What is the purpose of the Schedule Number in pipe manufacturing?

To specify the wall thickness of the pipe Signup and view all the answers

What happens to the inside diameter of a pipe as the wall thickness increases?

It decreases Signup and view all the answers

What is the formula to determine the inside diameter of a pipe?

d = D - 2t Signup and view all the answers

What is the purpose of a union in piping?

To provide an easy method for dismantling piping Signup and view all the answers

What is the advantage of screwed connections in piping?

Easy assembly and disassembly Signup and view all the answers

What is the purpose of a nipple in piping?

To make close connections Signup and view all the answers

How many general methods are used to join or connect lengths of pressure piping?

3 Signup and view all the answers

What is the primary purpose of grease fittings in piping systems?

To provide lubrication Signup and view all the answers

What is the function of a corrugated expansion joint?

To absorb endwise movement of the pipe Signup and view all the answers

What is the main consideration when designing piping supports?

To carry the weight of the pipe and its contents Signup and view all the answers

Why are pipe hangers or supports typically placed at 3-metre intervals?

As a general rule of thumb for ordinary installations Signup and view all the answers

What is the purpose of Tees and Crosses in piping systems?

For making branch line connections at 90° Signup and view all the answers

Where are pipe hangers and supports typically placed in relation to valves and heavy piping components?

Close to valves and other heavy piping components Signup and view all the answers

What is the purpose of a pipe anchor in a steam piping system?

To anchor the pipe to a fixed surface Signup and view all the answers

What type of thread is cut with a tap?

Female thread Signup and view all the answers

What is the purpose of a pipe reamer?

To remove the internal burr of the pipe Signup and view all the answers

What is the advantage of flanged connections over welded connections?

They permit disassembly Signup and view all the answers

What is the purpose of a gasket in flanged connections?

To prevent leakage at the connection Signup and view all the answers

Which type of flange is used in piping systems constructed from stainless steel or other costly materials?

Van Stone flange Signup and view all the answers

What is the purpose of a bushing in piping systems?

To connect a smaller pipe to a larger pipe Signup and view all the answers

What is the purpose of a plug?

To close off open pipe ends Signup and view all the answers

What is the purpose of a return bend?

To reverse the direction of a pipe run Signup and view all the answers

What is the purpose of a reducer in piping systems?

To reduce pipe size Signup and view all the answers

What is the primary function of ring joint gaskets in high-pressure systems?

To seal the connection between the flanges Signup and view all the answers

What is the main advantage of using welded connections over screwed or flanged connections?

They eliminate the possibility of leakage Signup and view all the answers

Why are backing or back up rings used in welding larger pipes?

To prevent weld metal from protruding inside the pipe Signup and view all the answers

What is the primary purpose of expansion bends in piping systems?

To allow for expansion of the pipe due to heat Signup and view all the answers

What type of expansion joint is illustrated in Figure 12?

Slip Expansion Joint Signup and view all the answers

What is the purpose of the semi-plastic packing in the Slip Expansion Joint?

To prevent leakage between the slip pipe and the joint body Signup and view all the answers

Why are ring joint gaskets generally used for high-pressure and special services?

Because they provide a more reliable seal Signup and view all the answers

What is the main disadvantage of using welded connections for piping?

They require a skilled welder Signup and view all the answers

What happens to the piping system when it is heated?

It expands in length Signup and view all the answers

What is the purpose of the flange and gasket surfaces being clean and free from foreign particles during assembly?

To ensure a reliable seal between the flanges Signup and view all the answers

Which type of material is commonly used for ash handling systems, sewage lines, and underground water lines?

Cast Iron Signup and view all the answers

What is the primary consideration when selecting materials for piping system?

Operating conditions of the piping system Signup and view all the answers

Which type of material is not suitable for pressurized service due to its brittleness?

Cast Iron Signup and view all the answers

Which ASME code addresses Power Piping and Process Piping?

B31.1, B31.3, and others Signup and view all the answers

Which type of steel is used for special applications?

Cast steel Signup and view all the answers

What is the most common piping material used in power plants?

Steel Signup and view all the answers

What is the primary purpose of supporting piping?

To carry the weight of the pipe, valves, fittings, and insulation Signup and view all the answers

What is the primary consideration when designing piping supports for steam pipes?

To support the weight of the pipe and its components Signup and view all the answers

What is the benefit of placing hangers and supports close to valves and other heavy piping components?

To distribute the weight of the valves and components more evenly Signup and view all the answers

What is the purpose of a corrugated expansion joint in a piping system?

To absorb a certain amount of endwise movement of the pipe Signup and view all the answers

What is the general rule-of-thumb for placing pipe hangers or supports in ordinary piping installations?

At 3-metre intervals Signup and view all the answers

What is the primary purpose of anchoring a steam pipe to a fixed surface?

To allow the pipe to expand its entire length towards an expansion joint Signup and view all the answers

What is the primary reason for using ring joint gaskets in high-pressure and special services?

To withstand high pressure and special services Signup and view all the answers

What is the main advantage of welded connections over flanged connections?

They eliminate the possibility of leakage Signup and view all the answers

What is the purpose of backing or back up rings in welding larger pipes?

To prevent weld metal from protruding inside the pipe Signup and view all the answers

What is the primary method of providing for expansion in pipelines?

Using expansion bends and expansion joints Signup and view all the answers

What happens to the piping system when it is heated?

It expands in length Signup and view all the answers

What is the purpose of lubricating bolt threads when assembling a flanged joint?

To facilitate tightening Signup and view all the answers

What is the primary consideration when using welded connections for piping?

The availability of skilled labor Signup and view all the answers

What is the purpose of the cross over method when tightening bolts in a flanged joint?

To tighten opposite bolts gradually and evenly Signup and view all the answers

What is the significance of the Nominal Pipe Size (NPS) number for pipes up to and including NPS 12?

It represents the nominal inside diameter of the pipe Signup and view all the answers

What is the advantage of using expansion bends over expansion joints?

They are preferred for high-pressure work Signup and view all the answers

Why does the inside diameter of a pipe decrease as the wall thickness increases?

Because the outside diameter of the pipe stays the same Signup and view all the answers

What is the purpose of the semi-plastic packing in the Slip Expansion Joint?

To prevent leakage between the slip pipe and the joint body Signup and view all the answers

What is the purpose of the Schedule Number in pipe manufacturing?

To indicate the wall thickness of the pipe Signup and view all the answers

What is the difference between the Imperial System and the metric system used to designate nominal pipe size?

The Imperial System uses NPS numbers and the metric system uses DN numbers Signup and view all the answers

What is the primary purpose of a return bend in piping systems?

To change the direction of a pipe run Signup and view all the answers

What type of thread is cut with a die?

Male thread Signup and view all the answers

What is the primary advantage of using screwed connections in piping systems?

They are easier to assemble and disassemble Signup and view all the answers

What is the purpose of removing the internal burr from a pipe after cutting?

To prevent the formation of an obstruction Signup and view all the answers

What is the significance of the DN number in the metric system used to designate nominal pipe size?

It indicates the nominal inside diameter of the pipe in millimeters Signup and view all the answers

Why are flanged connections generally used for high-pressure pipes?

Because they can withstand higher pressures than screwed connections Signup and view all the answers

What is the advantage of using flanged connections over screwed connections?

They are more convenient to assemble and disassemble Signup and view all the answers

What is the formula used to determine the inside diameter of a pipe?

d = D - 2t Signup and view all the answers

What is the purpose of a bushing in piping systems?

To connect a smaller pipe to a larger pipe or fitting Signup and view all the answers

What type of gasket is used for joining cast iron and steel flanges?

Full-face gasket Signup and view all the answers

What is the purpose of the wall thickness of a pipe?

To increase the strength of the pipe Signup and view all the answers

What is the significance of the Outside Diameter (OD) column in Table 1?

It indicates the outside diameter of the pipe in millimeters Signup and view all the answers

What is the purpose of tapping the smaller pipe eccentrically in a bushing connection?

To facilitate drainage of water Signup and view all the answers

What is the purpose of a plug in piping systems?

To close off an open pipe end or fitting Signup and view all the answers

What is the advantage of using Van Stone flanges in piping systems?

They are used for piping systems constructed from stainless steel or other costly materials Signup and view all the answers

What is the purpose of grinding the flange faces in a flanged connection?

To ensure the flange faces are absolutely flat and smooth Signup and view all the answers

What is the primary purpose of finishing cements in insulation applications?

To provide a finish to other insulation applications Signup and view all the answers

What is the temperature limit of insulating cements?

1038°C Signup and view all the answers

What is the primary component of magnesia insulation?

Magnesium carbonate Signup and view all the answers

What is the purpose of the reflective metal sheets in reflective metal insulation?

To reflect heat and prevent loss due to radiation Signup and view all the answers

What is the typical shape of pipe insulation?

Half-cylindrical Signup and view all the answers

What is the temperature limit of magnesia pipe covering?

320°C Signup and view all the answers

What is the primary characteristic of an efficient insulating material?

A large number of microscopic air pockets Signup and view all the answers

What is the primary purpose of insulating pipes carrying substances at a lower temperature than the surrounding air?

To prevent corrosion and dripping Signup and view all the answers

What is the temperature range of Calcium Silicate insulation?

38°C to 650°C Signup and view all the answers

What is the characteristic of Mineral Fibre (Rock and Slag Wool) insulation?

Practically neutral pH Signup and view all the answers

What is the primary advantage of Elastomeric insulation?

Cost efficiency for low-temperature applications Signup and view all the answers

What is the primary characteristic of Foamed Plastic insulation?

Lightweight with excellent moisture resistance Signup and view all the answers

What is the temperature limit of Refractory Fibre insulation?

Up to 1650°C Signup and view all the answers

What is the primary characteristic of Perlite insulation?

Low shrinkage and high resistance to corrosion Signup and view all the answers

What is the primary purpose of using insulation in piping systems?

To prevent corrosion and dripping Signup and view all the answers

What is the characteristic of Glass Fibre insulation?

Non-combustible and water absorbent Signup and view all the answers

What happens when the bimetal strip in a steam trap heats up?

It deflects downward Signup and view all the answers

What is the purpose of the small hole in the centre of the piston valve in an impulse trap?

To allow pressure to build up Signup and view all the answers

Why does the valve in a thermodynamic trap shut when steam enters the trap?

Because the steam expands and travels at high velocity Signup and view all the answers

What is the purpose of a sediment separator in a steam trap installation?

To separate sediment and condensate Signup and view all the answers

How is a trap typically installed in a piping system?

At the lowest point in the system Signup and view all the answers

What is the purpose of a bypass line with a globe valve in a steam trap installation?

To allow hand throttling while the trap is out of service Signup and view all the answers

How is the proper operation of a trap determined?

By opening the test valve and closing the outlet gate valve Signup and view all the answers

What is a characteristic of a correctly functioning thermodynamic or inverted bucket trap?

It intermittently discharges condensate with some flash steam Signup and view all the answers

What is the purpose of locking out and tagging out the trap for inspection?

To ensure the trap is out of operation Signup and view all the answers

What should be done on a regular basis to ensure the proper operation of the trap?

The sediment separator should be blown clean Signup and view all the answers

What is the primary purpose of a steam trap?

To separate steam and condensate Signup and view all the answers

What is the difference in the operation of mechanical and thermostatic traps?

Mechanical traps use floats, while thermostatic traps use temperature differences Signup and view all the answers

What is the advantage of ball float traps?

They work well with both light and heavy condensate loads Signup and view all the answers

What is the purpose of the bellows in a ball float trap?

To discharge air and CO2 Signup and view all the answers

How does an inverted bucket trap operate?

The bucket rises when condensate is present, and sinks when steam is present Signup and view all the answers

What is the primary purpose of thermostatic traps?

To remove condensate from radiators Signup and view all the answers

What is the operating principle of a bimetal steam trap?

The bimetal strips deflect when heated Signup and view all the answers

What is the disadvantage of ball float traps?

They are vulnerable to damage from water hammer Signup and view all the answers

What is the purpose of the vent in a ball float trap?

To discharge air and CO2 Signup and view all the answers

What is the common characteristic of mechanical and thermostatic traps?

They are both used to separate steam and condensate Signup and view all the answers

What is the term used to describe a series of loud, violent shocks produced within the piping of a steam system?

Water Hammer Signup and view all the answers

What happens when a motor driven centrifugal pump suddenly stops due to a power interruption or other pump 'trip'?

The water in the pump discharge line will stop and reverse direction Signup and view all the answers

What is a more dangerous form of water hammer?

Water hammer caused by the interaction of condensate and steam inside a pipe Signup and view all the answers

What happens when steam is introduced into a cold pipe or when flow in a steam pipe is very slow and normal cooling occurs?

The steam will revert to water and form condensate Signup and view all the answers

What is the purpose of traps fitted to main lines, branch lines, and separators for drainage purposes?

To drain condensate from the system Signup and view all the answers

What is the purpose of piping insulation in a power plant?

To reduce heat loss to the surrounding air Signup and view all the answers

What happens when a bubble of steam becomes enclosed by cooler condensate?

The steam bubble will implode Signup and view all the answers

What can cause water hammer if steam is admitted too quickly to a pipe containing water or condensate?

The steam will rapidly condense, forming a vacuum Signup and view all the answers

What can happen if steam is admitted to a pipe containing water or condensate without first removing the water or condensate?

Water hammer will occur Signup and view all the answers

What is the result of the inrushing water from one side of the steam bubble meeting the inrushing water from the opposite side of the bubble?

A loud bang or shock wave Signup and view all the answers

What is the purpose of steam separators in steam piping?

To remove moisture droplets and other suspended impurities from the steam Signup and view all the answers

What is the result of not constantly draining condensate from steam lines?

Water hammer and possible rupture of pipes or fittings Signup and view all the answers

What is the primary purpose of steam traps?

To discharge condensed water from steam lines and equipment Signup and view all the answers

Why is it important to recover condensate?

For heating, hot water needs, or for return to boilers Signup and view all the answers

Where should steam traps be installed?

Where condensate accumulates Signup and view all the answers

What is the consequence of not draining condensate rapidly?

Water hammer and possible rupture of pipes or fittings Signup and view all the answers

What is the primary function of reflective metal insulation?

To reflect heat and prevent loss due to radiation Signup and view all the answers

What is the temperature limit of magnesia pipe covering?

320°C Signup and view all the answers

What is the primary consequence of admitting moisture-carrying steam to turbines or engines?

Most undesirable operating condition Signup and view all the answers

What is the purpose of half-cylindrical sections in pipe insulation?

To fit over the pipe and reduce heat loss Signup and view all the answers

How do steam separators remove moisture droplets from steam?

By changing the direction of steam flow Signup and view all the answers

What is the composition of magnesia material?

Mainly of magnesium carbonate Signup and view all the answers

What is the primary characteristic of finishing cements or one-coat cements?

Used in the lower intermediate range and as a finish to other insulation applications Signup and view all the answers

What is the primary purpose of steam traps in a steam piping system?

To discharge condensed water from steam lines without allowing steam to escape Signup and view all the answers

Why is it necessary to constantly drain condensate from steam lines?

To prevent water hammer and pipe rupture Signup and view all the answers

What is the primary advantage of insulating cements?

Moderate insulation values Signup and view all the answers

What is the primary purpose of recovering condensate in a steam piping system?

For heating, hot water needs, or for return to boilers Signup and view all the answers

What is the result of not draining condensate rapidly from steam lines?

Water hammer and possible pipe rupture Signup and view all the answers

What is the primary function of the bellows in a mechanical trap?

To vent air and CO2 from the trap Signup and view all the answers

What is the disadvantage of the ball float trap?

It is vulnerable to damage from water hammer Signup and view all the answers

What is the primary principle of operation of thermostatic traps?

Differences in temperature between steam and condensate Signup and view all the answers

What is the purpose of the float in a mechanical trap?

To open and close the trap outlet valve Signup and view all the answers

What is the advantage of the inverted bucket trap?

It is not affected by changes in steam pressure Signup and view all the answers

What is the purpose of the plunger in a thermostatic trap?

To seat securely onto the discharge port Signup and view all the answers

What is the primary function of the corrugated bellows in a thermostatic trap?

To contain a volatile fluid that boils when heated by steam Signup and view all the answers

What is the primary characteristic of a thermostatic trap?

It operates based on differences in temperature between steam and condensate Signup and view all the answers

What is the primary advantage of the bimetal steam trap?

It operates based on differences in temperature between steam and condensate Signup and view all the answers

What is the purpose of the air vent in a mechanical trap?

To allow air to escape from the trap Signup and view all the answers

Which insulating material has a service temperature range of 38°C to 650°C?

Calcium Silicate Signup and view all the answers

What is the primary characteristic of a material that is suitable for use as insulation?

High insulating value Signup and view all the answers

What is the primary reason why pipes carrying substances at a lower temperature than the surrounding air should be insulated?

To prevent dripping and sweating Signup and view all the answers

Which insulating material is made from an inert siliceous volcanic rock, combined with water, and has a cellular structure of minute air cells?

Expanded Silica Signup and view all the answers

What is the purpose of adding binders to Perlite insulation?

To resist moisture penetration Signup and view all the answers

Which insulating material has a temperature limit of 1650°C?

Refractory Fibre Signup and view all the answers

What is the primary characteristic of a good insulating material?

Low thermal conductivity Signup and view all the answers

Which insulating material is non-combustible and has good sound control qualities?

Mineral Fibre Signup and view all the answers

What is the primary advantage of using Elastomeric insulation in low temperature applications?

No jacketing required Signup and view all the answers

What happens when the bimetal strip heats up in a thermodynamic trap?

It deflects downward to fully close the valve, keeping steam from passing to the condensate line. Signup and view all the answers

What is the primary reason why pipes carrying substances at a lower temperature than the surrounding air should be insulated to prevent corrosion?

To prevent corrosion due to the water or condensate in the pipe Signup and view all the answers

What is the purpose of the control cylinder in an impulse trap?

To provide a pressure difference for the piston valve to operate. Signup and view all the answers

Why does the valve in an impulse trap shut when steam enters the trap?

Because the steam expands and travels at high velocity under the piston disk. Signup and view all the answers

What is the purpose of the sediment separator in a steam trap installation?

To prevent foreign matter from entering the trap. Signup and view all the answers

How often should the trap be inspected and serviced?

Depending on the condition of the line, as needed. Signup and view all the answers

What is the purpose of opening the test valve and closing the outlet gate valve when inspecting the trap?

To determine if the trap is functioning properly. Signup and view all the answers

What is the characteristic of a correctly functioning thermodynamic or inverted bucket trap?

It discharges condensate intermittently with some flash steam. Signup and view all the answers

What is the purpose of the unions in a steam trap installation?

To permit the trap to be removed for repair or replacement. Signup and view all the answers

What happens when the condensate entering the trap is at its saturation temperature?

It flashes into steam, causing the valve to shut. Signup and view all the answers

Why is it important to follow safe work procedures when opening the test valve?

To prevent exposure to high-temperature condensate and steam. Signup and view all the answers

What is the primary cause of water hammer in a steam system?

Rapid condensation of steam inside a pipe Signup and view all the answers

What is the effect of higher steam pressures on water hammer?

Increasing the pressure differential Signup and view all the answers

What is the result of a steam bubble imploding in a pipe?

Generation of a shock wave Signup and view all the answers

Why is it important to remove condensate from steam pipes?

To prevent water hammer Signup and view all the answers

What is the purpose of bypass lines around traps in a steam system?

To ensure positive drainage Signup and view all the answers

What is the effect of admitting steam too quickly to a pipe containing water or condensate?

Water hammer Signup and view all the answers

What is the purpose of insulation in a power plant piping system?

To retain heat and prevent injury to personnel Signup and view all the answers

Pip4AE3 U7 C1 Review

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Questions and Answers

What is the primary consideration when selecting materials for pipe manufacturing?

Which ASME code addresses Power Piping and Process Piping?

What type of iron is used for screwed fittings?

What is the primary advantage of using cast iron in piping systems?

What type of material is commonly used for instrumentation and water services in power plants?

What is the main difference between seamless and welded steel pipes?

What is the purpose of the nominal pipe size?

What is the difference between NPS and DN?

What does the number represent for NPS 14 (DN 350) and larger pipe?

What is the purpose of the Schedule Number in pipe manufacturing?

What happens to the inside diameter of a pipe as the wall thickness increases?

What is the formula to determine the inside diameter of a pipe?

What is the purpose of a union in piping?

What is the advantage of screwed connections in piping?

What is the purpose of a nipple in piping?

How many general methods are used to join or connect lengths of pressure piping?

What is the primary purpose of grease fittings in piping systems?

What is the function of a corrugated expansion joint?

What is the main consideration when designing piping supports?

Why are pipe hangers or supports typically placed at 3-metre intervals?

What is the purpose of Tees and Crosses in piping systems?

Where are pipe hangers and supports typically placed in relation to valves and heavy piping components?

What is the purpose of a pipe anchor in a steam piping system?

What type of thread is cut with a tap?

What is the purpose of a pipe reamer?

What is the advantage of flanged connections over welded connections?

What is the purpose of a gasket in flanged connections?

Which type of flange is used in piping systems constructed from stainless steel or other costly materials?

What is the purpose of a bushing in piping systems?

What is the purpose of a plug?

What is the purpose of a return bend?

What is the purpose of a reducer in piping systems?

What is the primary function of ring joint gaskets in high-pressure systems?

What is the main advantage of using welded connections over screwed or flanged connections?

Why are backing or back up rings used in welding larger pipes?

What is the primary purpose of expansion bends in piping systems?

What type of expansion joint is illustrated in Figure 12?

What is the purpose of the semi-plastic packing in the Slip Expansion Joint?

Why are ring joint gaskets generally used for high-pressure and special services?

What is the main disadvantage of using welded connections for piping?

What happens to the piping system when it is heated?

What is the purpose of the flange and gasket surfaces being clean and free from foreign particles during assembly?

Which type of material is commonly used for ash handling systems, sewage lines, and underground water lines?

What is the primary consideration when selecting materials for piping system?

Which type of material is not suitable for pressurized service due to its brittleness?

Which ASME code addresses Power Piping and Process Piping?

Which type of steel is used for special applications?

What is the most common piping material used in power plants?

What is the primary purpose of supporting piping?

What is the primary consideration when designing piping supports for steam pipes?

What is the benefit of placing hangers and supports close to valves and other heavy piping components?

What is the purpose of a corrugated expansion joint in a piping system?

What is the general rule-of-thumb for placing pipe hangers or supports in ordinary piping installations?

What is the primary purpose of anchoring a steam pipe to a fixed surface?

What is the primary reason for using ring joint gaskets in high-pressure and special services?

What is the main advantage of welded connections over flanged connections?

What is the purpose of backing or back up rings in welding larger pipes?

What is the primary method of providing for expansion in pipelines?

What happens to the piping system when it is heated?

What is the purpose of lubricating bolt threads when assembling a flanged joint?

What is the primary consideration when using welded connections for piping?

What is the purpose of the cross over method when tightening bolts in a flanged joint?

What is the significance of the Nominal Pipe Size (NPS) number for pipes up to and including NPS 12?

What is the advantage of using expansion bends over expansion joints?

Why does the inside diameter of a pipe decrease as the wall thickness increases?

What is the purpose of the semi-plastic packing in the Slip Expansion Joint?

What is the purpose of the Schedule Number in pipe manufacturing?

What is the difference between the Imperial System and the metric system used to designate nominal pipe size?

What is the primary purpose of a return bend in piping systems?

What type of thread is cut with a die?

What is the primary advantage of using screwed connections in piping systems?

What is the purpose of removing the internal burr from a pipe after cutting?

What is the significance of the DN number in the metric system used to designate nominal pipe size?

Why are flanged connections generally used for high-pressure pipes?

What is the advantage of using flanged connections over screwed connections?

What is the formula used to determine the inside diameter of a pipe?