unit 2 pipe fittings

7/29/2019 Unit 2 Pipe Fittings

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UNITS IN THIS COURSE

UNIT 1 PIPING SYSTEMS

UNIT 2 PIPE FITTINGS

UNIT 3 VALVES

TABLE OF CONTENTS

Para Page

2.0 COURSE OBJECTIVE 3

2.1 PIPE FITTINGS 4

2.2 FLANGES 8

2.3 GASKETS 10

2.4 BLINDS 14

2.5 FILTERS 18

2.6 STRAINERS 25

2.7 STEAM TRAPS 29

2.8 TYPES OF STEAM TRAPS 31

2.0 COURSE OBJECTIVE

This course introduces the students to all major items of static equipment relating toa plant site. Upon completion of the course the trainees will have a generalunderstanding of the following.

Equipment Terminology.

Theory of operation.

Equipment construction.

Hands on operation.

safety features.

Equipment interaction with the overall process.

2.1 PIPE FITTINGS

Pipe fittings are classed according to the way they are joined to section of pipe. Thethree main types of pipe fittings are:M

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* Screwed.

Flanged.

Welded.

Screwed or flanged fittings must be used if the pipe has to be opened up or takenapart for cleaning, inspection or maintenance. The advantages and disadvantagesof each are as follows:

Screwed Fittings (Advantages)

Simple design.

Quick to install or remove.

Easy to open for cleaning or maintenance.

Cheaper to install.

Easy to repair / or replace.

Screwed Fittings (Disadvantages)

More leak problems.

More chance of corrosion at the threads.

Threads make pipework weaker.

Flanged Fittings (Advantages)

Strong.

Quick to open for cleaning and for repair.

Low corrosion possibility.

Flanged Fittings (Disadvantages)

More possibility of leaks occurring.

Prone to leaks if gaskets are not installed correctly.

Expensive to buy and install.

Heavy.

Difficult to insulate.

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Figure 2-1 Pipe Fittings

Figure 2-1 shows the most commonly used pipe fittings in a plant piping system.Table 1 explains what these fittings are used for.

NAME DESCRIPTION AND USE

Coupling This is a female fitting. Joins piping in a straightline.

Union. This is a female fitting which can be taken apart

Elbow (45 or 900 angle). Changes the direction of the piping by 45 or 90

Bushing. Different size Internal and external thread. Joins alarge pipe to a smaller pipe

Tee (T) joint.

Joins two or more branches together

Y joint . Joins two or more branches together

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Cross ( +) joint. Joins three or Four branches together

Plug A solid threaded male fitting. It screws into another fitting to plug an opening.

Cap An internally threaded female fitting. It screws onto

the pipe to seal the end.

Nipple This is a male fitting. A short section of threadedpipe. It often Joins two fittings

Reducers. Female fitting which reduce the size of the pipe.Most of the above fittings can be used as reducers

Table 1 Types of Fittings and Their Uses

Welded Joints

Figure 2-2 Welded Pipe Joints

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Figure 2-3 Screw, Flange and Welded Fittings

All fittings can be screwed, flanged or welded (See Figure 2-2 and 2-3). A properlywelded joint is as strong as the pipe itself. A welded system does not leak and

needs no maintenance. This is important on high pressure systems. The joints aremuch smoother on a welded system so insulating this type of system is easier.

For all permanent installations welding is used to join the sections of pipe and / orthe pipe fittings. Welded joints may be Butt-welded, Fillet welded or Sleeve-welded.Butt welding is the most common type of welded joint. Figure 2-2 shows sometypical welded pipe joints. Butt-welded joints prevent leaks and give fewercorrosion problems.

The advantages of welded joints are:

Very Strong.

Leakproof.

Maintenance free.

Smooth / small joints

Easy to insulate.

The disadvantage of welded joints is that they cannot be taken apart easily.

2.2 FLANGES

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Flanges are connecting devices on vessels, tank equipment and piping which givequick and easy connections and leakproof seals.

A flange has a contact surface which can be joined to another flange. Flanges haveholes around the edge so they can be bolted together.

Flanges are attached to piping in different ways. They can be screwed or welded.Welding is the strongest and most permanent. Figure 2-4 Shows different flangesurfaces

Flat Face (Plain)

Raised Faced (Serrated)

Ring Joint (Grooved)

Tongue and Groove

For low pressures and temperatures.

For high pressures and temperatures.

For high pressures and temperatures.

For high pressures and higher temperatures.

Flanges can be over 48" in diameter. They are made of different materials fordifferent purposes. They are rated according to the pressure they must hold. Theyare stamped with this rating.

Figure 2-4 Different Types of Flange Faces

Rating Rating

150 Low Pressure to 260 PSIG up to 200C 300300 Intermediate Pressure to 675 PSIG up to 200C 700600 High Pressure to 1350 PSIG up to 200C 1300

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900 Very High Pressure to 2000 PSIG up to 200C 20001500 Very Very High Pressure to 3375 PSIG up to 200C 30002500 Maximum Pressure to 5625 PSIG up to 200C 5600

As the operating temperature increases, the allowed operating pressure of theflange decreases. For example a 150 flange at 200 C operating temperature is

rated for 260 psig.

Higher flange ratings use more connecting bolts. The higher the flange rating themore connecting bolts / studs are used.

The whole area of a flat face flange is joined to the opposite flange.

Only a small inner part of a raised face flange is joined to the opposite flange face.The outer flange edges do not come in contact with each other.

A ring joint has a ring on one face that fits into a circular groove machined on theopposite flange face.

Figure 2-5 Blind Flange

Blind flanges are used to close off the ends of piping, valves and equipmentopenings. (See Figure 2-5) The flange bolts pass through the blind flange and themounted flange. After a gasket has been installed the bolts are tightened to thenormal operating specification to make a leakproof seal.

2.3 GASKETS

Gaskets are a thin plates which fit between the faces of two flanges. They areespecially important when joining two flat metal faces. It is hard to machine twometal faces so that they fit together without leaking. Thermal expansion andpressure causes the metal to lose its shape. The gaskets prevent leaks by filling inthe small gaps between the metal surfaces.

Many different types of gaskets are used in the plants. Gaskets are made fromdifferent materials. The material that is used must resist the temperature andchemical action of the fluid in the pipe. Gasket materials may be metallic ornon-metallic.. Some non-metallic gasket material is bought in sheet form and cut tosize. Many gaskets for special applications are already cut to size. Table 2 showssome different gasket materials and the different fluids they are used with.

FLUID GASKET MATERIAL

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Water Rubber. Asbestos.

Cold Oil Cor, Neoprene

Hot Oil. Asbestos. Ingot Iron

Gas (Low Temperature). Rubber

Gas (High Temperature) Asbestos.

Acids. Sheet Lead / Steel.

Table 2 Gasket Materials and Applications

Metallic Gaskets

Flat metallic gaskets are made of lead, copper, iron, steel, aluminium and monel.Flat metallic gaskets are a simple and cheaper method of sealing . They are strongenough for high temperature and pressure conditions. They can be used forpressures up to approximately 500 psig.

Tightening the bolts around the flanges forces the gasket material into the smallspaces in the flange faces to form a leakproof seal. Gaskets are made in differentshapes and different materials to suit any process.

The following are examples of non-metallic gasket materials and applications:

AsbestosRubber / NeopreneCorkVitonTeflon

High temperature / pressures.Low temperature / pressures.Low temperature / pressures.High / low temperatures / high pressuresHigh temperatures / pressures

The following are examples of metallic gasket materials and their applications:

Stainless steel.colonelAluminiumLeadTin

High temperature / pressures.High temperature / pressures.High temperature / pressuresLow temperature / pressures.Low temperature / pressures.

Figure 2-6 shows the most common types of metallic gaskets available for use inthe process plant.

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Figure 2-6 Metallic Gaskets

Spiral Wound Gaskets

Spiral wound gaskets are made of metallic strips in a special V shape. Theyare put together with an asbestos material between the Vs. The V's are

compressed between the two metal rings. The asbestos filled V's form agood compressible seal for the flange face.

They are used where expansion and contraction of the metal parts iscommon. Most spiral wound gaskets can be used for pressures up to 1200psig

Ring Joint Gaskets

Ring joint gaskets are made of stainless steel, iron, nickel, monel and copper.Ring joint gaskets give a seal like a welded joint. However, they are, betterthan a welded joint because they can be taken apart easily. The ring joint

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gasket fits into a-special groove machined into the flange face.. Thesegaskets are very good for very high pressures and temperatures. Thesegaskets can be used for pressures up to approximately 5000 psig.

Corrugated Gaskets

Corrugated gaskets are made of aluminium, copper, steel and monel. Thesegaskets require very low bolt tightening force for a leakproof seal. Thesegaskets are limited to approximately 300 psig.

Jacketed Gaskets

Jacketed gaskets are made of a soft non-metallic filler material covered by ametallic case. The filler material is usually asbestos or rubber. Thesegaskets are used where metallic parts expand and contract due to

temperature changes. They can be used for pressures up to approximately1200 psig.

Flat Metallic Gaskets

Flat metallic gaskets are made of lead, copper, iron, steel aluminium andmonel. Flat metallic gaskets are a simple and cheaper method of sealing .They have a good mechanical strength for high temperature and pressureconditions. They can-be used for pressures up to approximately 500 psig.

Gaskets are used when joining the following:

Flanges.Manways to vessels.inspection ports / hand holes to vessels.Heat exchanger parts. e.g., tube bundles , bell ends and endplates.Pump /turbine cases.Any metal to metal face joint that requires a leakproof seal.

Gaskets must be able to handle the following:

Various fluids.High and low temperatures.High and low pressures.Thermal expansion.Vibration / compression forces.

Always be sure to use the correct gasket for the process application. The gasketmust be the correct:

Right Size.Right Shape.

Right Material.Right Thickness.Installed correctly.

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Metallic gaskets are used for high temperature and high pressure applications. Thefollowing table lists some of the metals used in gaskets and their maximumoperating temperatures.

Material c Material CTin 93 Stainless Steel 538

Lead 100 Titanium 538Bronze 260 Silver 649

Aluminium 427 Monel 816

Special metallic gaskets are available for temperatures up to 1100C.

2.4 BLINDS

A blind is a circular metal plate which is placed between two flanges. It stops theflow of liquids. It is used to isolate a section of piping, usually for maintenance.

After the blind and gaskets have been installed, the flange bolts are tightened tomake a leakproof seal. The bolts are tightened to the normal operatingspecification. The blind fits inside the circle of flange bolts as shown in Figure 2-7

Figure 2-8 Blank Blind Installed Between Flanges

Sometimes vessels and pipework need to be opened for inspection, cleaning andrepair.

Before a piece of equipment can be opened it must be totally isolated from theprocess. Blinds are used to isolate the equipment. Blinds are circular metal platesinstalled between two flanges or at the end of a pipe to stop any fluid from passing

a certain point. They are installed with a gasket on each side to ensure no fluidscan leak past and cause a safety hazard for the maintenance workers.

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As an operator you must be able to isolate correctly any piece of equipment or unitin your section of the plant to ensure the safety of all workers. When isolating apiece of equipment or pipework the following must be performed.

Depressurise and purge all lines with an inert gas (usually nitrogen) beforeopening any line or piece of equipment.

Blind all lines-to and from the equipment.

Make a blind list to ensure that all blinds are installed correctly and removedwhen the work is complete.

Use the correct type and size of blind.Purge all the air from the lines using an inert gas (usually nitrogen) before

starting the equipment or process.

Blinds are made in three different types: See Figure 2-9

Figure 2-9 Blinds.

Blank Blind Temporary installation only. Installed betweentwo flanges.

Spectacle Blind Permanent installation between two flanges.It is easier to open and close.

Blind Flange Permanently installed at the end of a pipe or vessel nozzle to stop fluid flow.

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Figure 2-10 Typical Blinding of a Vessel

Process Line Blind inOper. Initials

Blind OutOper Initials

Feed Inlet (1)

Feed Inlet (2)

Reboiler Outlet

Reboiler Inlet

Vapour Inlet

Product Inlet

Table 3 Blind List for the Vessel in Figure 2-10.

Table 3 is a blind list for the vessel in Figure 2-10

Before you sign the blinds in, as an operator you must:

Check to make sure the blind is in the correct position.

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Check that there is a gasket installed on each side of the b

Check to make sure the nuts and bolts on the flange are tight

Before you sign the blinds out, as an operator you must:

Ensure all the work on the equipment is complete.

Check that the inside of the vessel is clean and free from t

Check that all the blinds have been removed.

1. Check that new gaskets have been installed between the .

Check that all flanges are aligned.

Check that all nuts and bolts have been tightened to the cc specification.

YOU MUST ALWAYS REMEMBER THAT BLINDS ENSURE THE SAFETY OFEVERY PERSON WORKING IN OR ON A PIECE 0F EQUIPMENT. YOU MUSTENSURE THAT THEY ARE INSTALL CORRECTLY AND HAVE BEEN REMOVEDWHEN THE WORK COMPLETE.

2.5 FILTERS

The most common types of filter are:

Edge Type Filter.

Sock Type Filter.

Cartridge Type Filter.

Mixed Bed Filters.

A filter is a device used to remove unwanted substances from the process fluidsand from a system within the process e.g., amine, glycol, air. To do this the fluid ispassed through a material which allows the fluid to pass but catches any solid

contaminant. The filter material is usually cloth, paper or wire mesh. The thicknessand porosity of the surface of the material is very important. It determines both theamount of fluid which can be handled by the filter and the size of the contaminantwhich will be filtered out.

Filters do the following:

They prevent abrasive material entering pumps and turbines. They reduce pipewear due to erosion.

They keep valves clean so they can operate freely.They keep process fluids pure so that treating chemicals

operate properly.They keep towers and vessels clean.

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They keep heat exchangers and reboilers free of dirt.

They keep contaminants out of the sales products.

Filters also maintain good / correct instrumentation operation

They keep contaminants from blocking air lines to and from control valves.They keep contaminants from blocking or damaging small instrument orifices.They keep contaminants from blocking gauge glasses or level control column

legs.

All filters are made up of two main parts:

The housing (the outside case) which contains the fluid and the filter internals.

The filter element or elements. through which the fluids pass. This is the part

that traps the contaminants.

Some filters can be removed and cleaned when they become contaminated. Mostfilters have replaceable elements. These elements are specially designed to fit theparticular filter. When the element becomes contaminated it is changed. The usedelement is thrown away.

Most filters cause the fluid flowing through them to make a sharp turn. The largerparticles to be removed are too heavy to make the sharp turn. These drop to the

bottom of the filter. Other particles are trapped in the filter element.

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Figure 2-11 Edge Type Filter

A filter in which the element is not changed is shown in Figure 6-24.

This is called an edge type filter. It is used to remove impurities from an oil line. Thisfilter is also called a full flow filter. That means all the oil flows through the filter.The filter has a metal case with a large number of thin metal plates inside. Theplates are arranged on top of each other. The plates have small bumps on thesurface. Every second plate is connected to a shaft which can be rotated. The fluidflows down, across and between the plates.. Any particles or contaminants aretrapped between the plates and the small bumps.

To clean the filter the shaft is turned manually. This turns 50% of the plates so the

contaminants drop to the bottom of the case. These contaminants collect in thebottom of the filter (the sump). These contaminants can be drained off by removingthe drain plug when necessary.

Figure 2-12 Paper Filter / Cartridge Filter

In cartridge type filters either the filter element or the whole filter are replaceable.

The housing can be bolted in place or it is threaded so it can be screwed onto thefilter body. When the element becomes contaminated it is thrown away and a newelement is installed.

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The cartridge type filter has a large metal housing. The cartridge elements areridged cardboard or metal. They have cloth or paper type material inside. They arestrong and will not break under high differential pressure. These filters are used inprocess fluid systems.

Sock Type Filter

Figure 2-13 Sock Type Filter

These filters have a large metal housing. They have sock type filter elements.These are long circular tubes of cotton or cloth material through which the fluidpasses. The particles / contaminants are trapped in the fibres of the materials.

These filters are very good for handling large quantities of particles / contaminants.They are used for low differential pressures. This type of filter will break under highpressure. When the filter elements become blocked they are thrown away andreplaced. This type of filter is used in Amine systems.

Mixed Bed Filters

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Figure 2-14 Example of a Mixed Bed Filter

These filters have a large circular metal housing. They are filled with layers ofdifferent materials. e.g., gravel, sand and anthracite. The particles / contaminantsare trapped between the grains of gravel, sand and anthracite. The filter is cleanedwhen the fluid flow is reversed, The reversed flow forces the particles /contaminants out to drain. This type of filter is used for water purification.

Filters must be cleaned and replaced regularly. A blocked / plugged filter restrictsthe fluid flow in a line and this must not be allowed to happen. A defective filtersystem may allow contaminants to remain in the line. You must not forget tomaintain filters.

Precoat Filters

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Figure 2-15 Principle Operation of a Precoat Filter

Precoat filtration is used to remove very small solid particles, oil particles, and evenbacteria from water. This method is only used for small quantities of water whichcontain small quantities of contaminants.

Precoat filtration may be used after the normal clarification processes. It produceswater which contains very small amounts of suspended solids. It is used forspecific purposes. For example, precoat filters are often used to remove oil fromcontaminated steam condensate.

In precoat filtration, the precoat material can be organic, (contains living cells). Thisacts as a membrane between the two fluids. The base must prevent passage ofthe precoat material without restricting the flow of filtered water. It must be able tooperate under high pressure differentials. Filter cloths, porous stone tubes, andwire wound tubes are used as base materials.

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The supporting base material is first precoated with a slurry of precoat material.More slurry (body feed) is usually added during the filter run. When the materialremoved by the filter has built up there will be a big pressure drop across the filter.Then the filter coating is removed by backwashing. The filter bed is then precoatedand returned to service. Chemical coagulants are not usually -needed. However, if

an extra pure effluent is needed, they may be used.

MICRON RATING

There are a number of different types of filters for different fluids and contaminantproblems. All filters are marked with a micron rating.

The micron rating tells you the size of the holes in the filter or the size of theparticles the filter will trap. A low micron rating means the filter element has smallholes. A higher rating means larger holes. The holes in ratings below 40 microncannot be seen with the naked eye.

2.6 STRAINERS

A strainer is a wire mesh screen. It is used to remove solid particles from a fluid.The fluid may be water, oil, gas, steam or any other fluid carried by a pipingsystem. Strainers are usually installed in front of valves, pumps or regulators forprotection. Particles allowed to flow through a piping system will cause pipe wallsand piping system to become worn. They may also cause valves, pumps andregulators to block so they cannot operate properly.

The size of the wire mesh used in a strainer will determine the size of the particles

which will be removed or blocked by the strainer. The strainers used in pipingsystems are usually designed to allow free fluid flow through the system with verylittle pressure loss. Most strainers contain a blow-out or clean-out plug. This allowsthe strainer to be cleaned.

There are various types of strainer:

Figure 2-16 Circular Strainer

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Circular Strainers are made of two circular screens separated by a small space.The inner screen has larger holes than the outer screen. The fluid flows from theinside out. These are used upstream of steam traps.

Figure 2-17 Disc Strainer

A Disc Strainers is a round plate or disc with holes in it. It is installed between twoflanges. It will hold small volumes of large particles. It is cheap to make and easy toinstall and remove. It is installed before pumps.

Figure 2-18 Cone Strainers

Cone Strainers are made in the shape of a cone. It can handle a large volume ofparticles / contaminants. This type of strainer is difficult to install and remove. It ismainly' used to protect equipment during the start-up phase of a process.

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Figure 2-19 Cone Strainer Installed between a Flange

Figure 2-20Y-Type Strainer

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Y-Type Strainers are usually used in pipelines of three inches or less. The fluidflows through the screen located in the leg. Any sediment is trapped there.

The screen can be removed and cleaned by opening the leg cover. The leg cover is

either threaded or flanged for this particular purpose. These Y-type strainers can beinstalled in the horizontal or vertical position. However, the leg must always pointDownwards.

Figure 2-21 Simplex Basket Strainer

Basket Strainers are generally used in larger piping systems but can sometimes beused in smaller piping systems. This type of filter allows a basket type screen to be

inserted or removed through the top of the strainer. It is usually flanged or has ayoke type cover which can be removed quickly. Basket strainers are installed eitheras a simplex or duplex. The simplex is used where the line can be shut down longenough to allow time for cleaning the basket. The duplex permits continuousoperation and does not require the system to be shut down for cleaning.

2.7 STEAM TRAPS

A steam piping system may contain a small amount of water along with the steam.This water must be removed from the steam line. Steam is used to operate highspeed turbines and other equipment. Water in a steam line can damage high speed

Turbines.

Water may also erode valve faces and seals. Impurities in the water can also cause

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erosion and damage.

The steam traps main function is to remove condensate (water) from the steam lineand to prevent steam from entering the condensate lines.

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A steam trap is an automatic valve. It is installed in a piping system. It allowsthe release of water (condensate) and air without releasing steam. There isno drop in line pressure when a steam trap operates.

Steam traps are installed in lines if the condensate must be drained off asquickly as it collects. They allow the condensate to be recovered

for heating, for hot water or for return to the boilers. They are used in steampiping, separators and all steam heated or steam operated equipment.

Water Hammer

If water is allowed to remain in a steam line it can cause problems such aswater hammer, erosion, corrosion and loss of efficiency.

Water hammer is a series of shocks produced by a sudden change in thespeed ofthe water flowing in a pipeline. This sudden change in the speed of

the water may be caused by a valve opening or closing very quickly. It canalso be caused by very fast condensation of a pocket of steam within thepipe.

If a pump stops suddenly because of a power failure this can cause waterhammer. This happens because the water in the pump discharge line willstop and reverse its direction of flow. The rapid closing of the check valve atthe pump will cause water hammer.

Water hammer will also happen if steam goes into a pipe that contains somewater or condensate. As the steam passes over the water it condenses.

This-rapid condensation causes a vacuum to form in the pocket. the waterrushing into this vacuum will produce water hammer. This can cause damageto the pipework and fittings.

Erosion can occur when water enters high speed turbine blades. This causeserosion damage (rapid wear) to the turbine blades.

Corrosion can occur when water lays in low sections of pipework and turbinecasings.

Loss of efficiency will occur when water enters reboilers and heat exchangers

because it lowers the heat energy that is available. Loss of efficiency will alsooccur when water enters steam ejectors as it reduces their pumpingefficiency.

2.8 TYPES OF STEAM TRAPS

THERMOSTATIC TRAP

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Figure 2-22 Thermostatic Trap

The thermostatic steam trap responds -to The Temperature difference between thesteam and the condensate. Both steam and condensate may enter the trap. Whensteam enters -.he trap the fluid inside the bellows expands and evaporates. Thisexpands the bellows and closes the valve. (See Figure 2-22)

When the fluid in the trap cools and condenses to water the fluid in the bellowscondenses This makes the bellows contract. This opens the outlet valve and thecondensate escapes into the condensate line. When hot steam re-enters the trap itagain expands the bellows and closes the valve.

Figure 2-23 Float Thermostatic Trap

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FLOAT THERMOSTATIC TRAP

When hot steam enters the trap inlet it cannot move the float. So, the trap remainsclosed. When the steam condenses to water, the water will cause the float to rise.This will open the outlet and allow the condensate to leave the trap and enter thecondensate line.

INVERTED BUCKET TRAP

Figure 2-24 Inverted Bucket Trap

When there is only steam in the trap, the steam pressure will hold the bucket up andkeep the outlet valve closed. When the bucket fills with condensate the bucket willsink to the bottom of the trap and open the outlet valve. This allows the condensateto leave the trap.

Figure 2-25 Open Bucket Trap

THERMODYNAMIC TRAP

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Figure 2-26 Thermodynamic Trap

Thermodynamic traps use the heat energy in steam or in hot condensate to openand close the trap. When cool condensate or air enter the trap they flow upwardthrough the inlet orifice. They tilt the disc upward to pass through a hole in the seatplate. They then flow through the discharge ports to the trap outlet. If steam entersthe trap it flows at high speed under the disc. This causes pressure to build up inthe chamber above the disc.

The build-up of pressure forces the disc down which closes the trap. If hotcondensate enters the trap it will flash into steam as it leaves the inlet orifice. Thisflash steam will also flow at high speed under the disc. This causes a reduction inpressure and flash steam above the disc will again force the trap to close. The trapstays closed until the steam above the disc condenses.

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Figure 2-27 Trap operation

Method of checking steam trap operation

Listen to it:

A properly working steam trap will be silent except when it opens to allow thecondensate to pass out.

Check upstream and downstream drains:

Upstream should be straight steam.Downstream only hot water.

Check upstream and downstream pressure gauges:

Upstream should have steam header pressure (250 psig). Downstream should havecondensate pressure only (35 psig).

Check temperature before and after the steam trap (Wearing gloves)

Upstream side should be hotter

Where are steam traps installed:

Bottom of large steam headers.

End of steam headers.

Before steam turbines.

Bottom of steam turbine cases.

Outlet of steam turbines.

Before reboilers.

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On all steam lines.


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Figure 2-28 Typical Steam System

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Steam Separators

Figure 2-29 Typical Steam Separators

Steam separators, (sometimes called steam purifiers) are devices which purifysteam. When they are installed in the steam line they will remove moisture dropletsand other suspended impurities in the steam. To do this, the separator causes thesteam to suddenly change its direction of flow it causes the steam to start circulatingquickly. Both of these actions cause the moisture and other particles to be thrownout of the flow of steam. The moisture particles collect at the bottom and pass outthrough a drain.

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7:Pipingsystems

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2-Pip

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unit 2 pipe fittings

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