PLAN O1 PLAN 32

PLAN O2 PLAN 41

PLAN 11 PLAN 51

PLAN 12 PLAN 52

PLAN 13 PLAN 53

PLAN 21 PLAN 54

PLAN 22 PLAN 61

PLAN 23 PLAN 62

PLAN 31

PLAN 01

Intergral recirculation from pump discharge to seal. Recommended for clean pumpage only.Care must be taken that intergral recirculationis sufficient to maintain stable face condition.

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PLAN 02

oPlugged connections for

o possible future circulating fluid.

Dead ended seal chamber with no circulation of flushed fluid.

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PLAN 11

Reciculation from pump discharge through a flow control orifice to the seal.The flow enters the seal chamber adjacent to the mechanical seal faces,flushes the faces and flows across the seal backinto the pump.

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PLAN 12

Reciculation from pump discharge through a strainer & flow control orifice to the seal.This plan is similar to plan 11 but with addition of strainer to remove occasionalparticles. Strainers are not normally recommended because of blockage couldcause failure.

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PLAN 13

Reciculation from the seal chamber through a flow control orifice and back to pump suction.

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PLAN 21

Reciculation from pump discharge through a flow control orifice and a cooler,then into the seal chamber.

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p

PLAN 22

Reciculation from pump discharge through a strainer, a flow control orifice and a cooler, then into the seal chamber. Strainers are not normally recommended because of blockage could cause seal failure.

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p

PLAN 23

Reciculation from pumping ring in the seal chamber through a cooler and backto the seal chamber. This plan can be used on hot applications to minimize heatload on cooler by cooling only the small amount of liquid that is recirculated.

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p

PLAN 31

Reciculation from pump discharge through a cyclone separator delivering the clean fluid to the seal chamber. The solids are delivered to the pump suction line.

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PLAN 32

Fluid is injected into the seal chamber from an external source. Care must be exercised in choosing a proper source of seal flush to eliminate the potentialfor vaporization of injected fluid and to avoid contamination of the fluid beingpumped with the injected flush.

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DETAILS

p

PI

PLAN 41

Reciculation from pump discharge through a cyclone separator delivering the clean fluid to a coler and then to the seal chamber. The solids are delivered to the pump suction line.

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p

Vent

PLAN 51

Quench Inlet

Quench Outlet (Plug)

External reservoir providing a dead -ended blanket of fluid to the quench connection of the gland.

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Reservoir

Vent

PLAN 52

Normally Open

BO

BI

External reservoir providing buffer fluid for the outer seal of an unpressurised dual seal arrangement. During normal operation, circulation is maintained by aninternal pumping ring. The reservoir is usually continuously vented to a vapor recovery system and is maintained at a pressure less than the pressure in theseal chamber

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Reservoir

FI

PIPS

External pressure source

PLAN 53

Normally Open

BO

BI

Pressurised external barrier fluid reservoir supplying clean fluid to the sealchamber. Circulation is by an internal piping ring. Reservoir pressure is greater than the process pressure being sealed. Typically used with arrangement 3 pressurised dual seal.

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DETAILS

Reservoir

FI

PIPS

PLAN 54

BO

BI

Pressurised external barrier fluid reservoir or system supplying clean fluid to the seal chamber. Circulation is by an external pump or pressure system. Reservoir pressure is greater than the process pressure being sealed. Typically used with arrangement 3 pressurised dual seal.

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PLAN 61

Plugged Inlet

Plugged Outlet

Tapped connections for the purchaser's use. Typically this plan is used when the purchaser is to provide fluid (such as steam, gas or water) to an auxillarysealing device.

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PLAN 62

External source providing a quench. The quench may be required to prevent solids from accumulating on the atmospheric side of the seal.Typically used with a close clearance throttle bushing.

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Plan 31

Plan 32

Plan 52

Plan 31 is specified only for services containing solids with a specific gravity twice or more that of the process fluid. A typical use of this plan is water service to remove sand or pipe slag. In API plan 31 product is routed from the discharge of the pump into a cyclone separator. Solid particles are centrifuged from the stream and routed back to suction. The seal flush is routed from the cyclone separator into the flush connection on the seal plate. Throat bushings are required when plan 31 is specified.

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Plan 32 is used in services containing solids or contaminants where a suitable cleaner or cooler flush will improve the seal environment. It is also used to reduce flashing or air intrusion(in vacuum services) across the seal faces by providing a flush that has a lower vapor pressure or that will raise the seal chamber pressure to an acceptable level. The external flush must be continuous and reliable even during non-standard situations such as start-up or shutdown. The external flush must also be compatible with the process stream.

In API plan 32, the flushing product is brought from an external source to the seal. This plan is almost always used in conjunction with a close-clearance throat bushing. The bushing can function as a throttling device to maintain elevated pressure in the stuffing box or as a barrier to isolate the pumped product from the seal chamber. Plan 32, is not recommended for cooling only, as the energy costs be very high. Product degradation costs also must be considered when using a plan 32.

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Plan 52 or arrangement 2 unpressurised dual seal systems are used in services where no leakage to atmosphere can be tolerated. A plan 52 system consistes of dual machanical seals with a buffer fluid between them. The buffer fluid is contained in a seal pot which is vented to a vent system, thus maintaining the buffer fluid pressure close to atmosphereic. Inner seal leakage will be product leakage into the buffer fluid. There will always be some leakage.

Plan 53

Plan 54

Plan 52 works best with clean, non polymerizing products which have a vapor pressure higher than the buffer fluid pressure.

These products will flash in the seal pot and the vapor van escape to the vent system. If the product has a vapor pressure

lower than the buffer fluid or seal pot pressure, the leakage will remain a liquid and will contaminate the buffer fluid.

Should an inner seal leak not be detected early, the heavier process fluid will displace the buffer fluid and can result in the area between the two seals being completely filled with product. In that case, an outer seal leak can result in product being released to the atmosphere. Plan 52 is discouraged for dirty or polymerising products as well. Plan 53 should be considered as an alternative for these situations.

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Plan 53 or arrangement 3 pressurised dual seal systems are used in services where no leakage to atmosphere can be tolerated. A plan 53 system consists of dual mechanical seals with a barrier fluid between them. The barrier fluid is contained in a seal pot which is pressurized to a higher pressure(usually 20-25 PSID) than the pump seal chamber. Inner seal leakage will be barrier fluid leakage in to the product. There will always be some leakage.

Plan 53 is usually chosen over plan 52 for dirty, abrasive or polymerizing products which would either damage the seal faces or cause problems with the buffer fluid system if plan 52 were used. There are two disadventages to plan 53 which must be considered. There will always be some leakage of barrier fluid in to the product. Normally, this leakage will be minute, and the leakage rate can be monitored by monitoring the seal pot level.

However, the product must be able to accommodate a small amount of contamination from the barrier fluid. Second, a plan 53 system is dependent on having the seal pot pressure maintained at the proper level. If the seal pot pressure drops, the system will begin to operate like a plan 52, or unpressurised dual seal, which does not offer the same level of sealing integrity.

Specifically, the inner seal leakage direction will be reversed and the barrier fluid will, over time become non-contaminated with the process fluid with the problems that result, including possible seal failure.

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Plan 54 systems are also pressurized dual seal systems with inner seal leakage into the pumped product. In a plan 54, a

cool clean product from an external source is supplied to the seal as barrier fluid. The supply pressure of this product is 20 or

more PSID greater than the pressure the inner seal is sealing against.

This results in a small leakage of barrier fluid into the process. If it were, thefailure of one inner seal could contaminate the

entire barrier fluid system and cause additional seal failures. Plan 54 is often used in services where the pumped fluid is hot,

comtaminated with solids, or both. When plan 54 is specified, carefully consider the reliability of the barrier fluid source.

Plan 62

when the source is interrupted or contaminated, the resultant seal failures have been very expensive. A properly engineered

barrier fluid system is typically complex and often expensive. Where these systems are properly engineered, they provide

among the most reliable systems.

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In API plan 62, a quench stream is brought from an external source to the atmosphereic side of the seal faces. The quench stream van be low-pressure steam, nitrogen, or clean water. It is used in selected single seal applications to exclude the presence of oxygen to prevent coke formation(for example, hot hydrocarbon services) and to flush away undesirable material buildup around the dynamic seal components(for example, caustic and salt services).

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Plan 31 is specified only for services containing solids with a specific gravity twice or more that of the process fluid. A typical use of this plan is water service to remove sand or pipe slag. In API plan 31 product is routed from the discharge of the pump into a cyclone separator. Solid particles are centrifuged from the stream and routed back to suction. The seal flush is routed from the cyclone separator into the flush connection on the seal plate. Throat bushings are required when plan 31 is

Plan 32 is used in services containing solids or contaminants where a suitable cleaner or cooler flush will improve the seal environment. It is also used to reduce flashing or air intrusion(in vacuum services) across the seal faces by providing a flush that has a lower vapor pressure or that will raise the seal chamber pressure to an acceptable level. The external flush must be continuous and reliable even during non-standard situations such as start-up or shutdown. The external flush must also

In API plan 32, the flushing product is brought from an external source to the seal. This plan is almost always used in conjunction with a close-clearance throat bushing. The bushing can function as a throttling device to maintain elevated pressure in the stuffing box or as a barrier to isolate the pumped product from the seal chamber. Plan 32, is not recommended for cooling only, as the energy costs be very high. Product degradation costs also must be considered when

Plan 52 or arrangement 2 unpressurised dual seal systems are used in services where no leakage to atmosphere can be tolerated. A plan 52 system consistes of dual machanical seals with a buffer fluid between them. The buffer fluid is contained in a seal pot which is vented to a vent system, thus maintaining the buffer fluid pressure close to atmosphereic. Inner seal

Plan 52 works best with clean, non polymerizing products which have a vapor pressure higher than the buffer fluid pressure.

These products will flash in the seal pot and the vapor van escape to the vent system. If the product has a vapor pressure

lower than the buffer fluid or seal pot pressure, the leakage will remain a liquid and will contaminate the buffer fluid.

Should an inner seal leak not be detected early, the heavier process fluid will displace the buffer fluid and can result in the area between the two seals being completely filled with product. In that case, an outer seal leak can result in product being released to the atmosphere. Plan 52 is discouraged for dirty or polymerising products as well. Plan 53 should be considered

Plan 53 or arrangement 3 pressurised dual seal systems are used in services where no leakage to atmosphere can be tolerated. A plan 53 system consists of dual mechanical seals with a barrier fluid between them. The barrier fluid is contained in a seal pot which is pressurized to a higher pressure(usually 20-25 PSID) than the pump seal chamber. Inner seal leakage

Plan 53 is usually chosen over plan 52 for dirty, abrasive or polymerizing products which would either damage the seal faces or cause problems with the buffer fluid system if plan 52 were used. There are two disadventages to plan 53 which must be considered. There will always be some leakage of barrier fluid in to the product. Normally, this leakage will be minute, and

However, the product must be able to accommodate a small amount of contamination from the barrier fluid. Second, a plan 53 system is dependent on having the seal pot pressure maintained at the proper level. If the seal pot pressure drops, the system will begin to operate like a plan 52, or unpressurised dual seal, which does not offer the same level of sealing

Specifically, the inner seal leakage direction will be reversed and the barrier fluid will, over time become non-contaminated

Plan 54 systems are also pressurized dual seal systems with inner seal leakage into the pumped product. In a plan 54, a

cool clean product from an external source is supplied to the seal as barrier fluid. The supply pressure of this product is 20 or

This results in a small leakage of barrier fluid into the process. If it were, thefailure of one inner seal could contaminate the

entire barrier fluid system and cause additional seal failures. Plan 54 is often used in services where the pumped fluid is hot,

comtaminated with solids, or both. When plan 54 is specified, carefully consider the reliability of the barrier fluid source.

when the source is interrupted or contaminated, the resultant seal failures have been very expensive. A properly engineered

barrier fluid system is typically complex and often expensive. Where these systems are properly engineered, they provide

In API plan 62, a quench stream is brought from an external source to the atmosphereic side of the seal faces. The quench stream van be low-pressure steam, nitrogen, or clean water. It is used in selected single seal applications to exclude the presence of oxygen to prevent coke formation(for example, hot hydrocarbon services) and to flush away undesirable material buildup around the dynamic seal components(for example, caustic and salt services).

AFFINITY LAWS

= = =

Vaporizer Heat Duty (MMKcal/Hr) 8.1

Calorific Value ( Kcal/Kg) 9000

Vaporizer Efficiency (%) 90

Fuel required (Kg/ Hr) 1000

GPM2 D2 Ö H23Ö BHP2

GPM1 D1 Ö H13Ö BHP1