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    CHAPTER - 1

    PUMPS GENERAL

    1.1 DEFINITION AND DESCRIPTION

    It is a machine that imparts energy to a fluid. This energy infusion can cause a

    fluid to flow rise to a higher level, or both. The centrifugal pump is an extremely simple

    machine. It is a member of family known as rotary machines and consists of two basic

    parts:

    A). the rotary element or impeller and;

    B). the stationary element or casing (volute).

    Centrifugal pumps are often considered as simple components to be included in

    more complex circuits. In reality great care must be taken with regard to their

    configuration, which must always be considered in relation to the system's

    characteristics, pumping requirements and the user's individual needs. Selecting an

    impeller pump, in fact, requires in-depth knowledge of the specific operating conditions:

    whoever manufactures centrifugal pumps must know how to evaluate all information

    useful achieving the best possible hydrodynamic design. To guarantee the proper use of

    the plastic anti-corrosion pumps, the user must provide the manufacturer thorough

    details regarding the specific application and in particular the liquid that the pump is

    intended handle. Furthermore, to ensure that similar pumps work at full capacity and

    efficiently demonstrate their special characteristics, the pump itself must be installed

    carefully to evaluate the effects of operating conditions with the aggressive liquid.

    Machine designed to:

    a. Transport fluid and;

    b. Add energy.

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    1.2 TYPES OF PUMP

    There are two types of pump:

    i. Centrifugal pump.

    a. Single stage;

    b. Multi stage;

    c. Split casing and;

    d. Axial.

    ii. Positive displacement

    a. Reciprocating;

    b. Gear and;

    c. Rotary.

    1.2.1 CENTRIFUGAL PUMP

    Moderate pressure (up to 6000 m/WC )

    Moderate capacity ( up to 10000 m3/ hr )

    Up to 30000 m3/hr in case of concrete volute pump.

    1.2.2 POSSITIVE DISPLACEMENT (RECIPROCATING)

    High pressure ( up to 10000 m/ WC )

    Low capacity up to 1000 m3/hr.

    Lubrication oil pumps.

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    1.3 COMPONENTS OF CENTRIFUGAL PUMP

    FIGURE SHOWING THE FLOW AND PARTS OF CENTRIFUGAL PUMP (CS VIEW)

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    Figure representing General components of a Centrifugal Pump

    1.3.1 Stationary Components

    Casing

    Casings are generally of two types: volute and circular. The impellers are fitted inside

    the casings.

    1. Volute casings build a higher head; circular casings are used for low head and high

    capacity.

    o A volute is a curved funnel increasing in area to the discharge port. As the area of the

    cross-section increases, the volute reduces the speed of the liquid and increases the

    pressure of the liquid.

    o One of the main purposes of a volute casing is to help balance the hydraulic pressure

    on the shaft of the pump. However, this occurs best at the manufacturer's recommended

    capacity. Running volute-style pumps at a lower capacity than the manufacturer

    recommends can put lateral stress on the shaft of the pump, increasing wear-and-tear on

    the seals and bearings, and on the shaft itself. Double- volute casings are used when the

    radial thrusts become significant at reduced capacities.

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    2. Circular casing:

    Circular casing have stationary diffusion vanes surrounding the impeller

    periphery that convert velocity energy to pressure energy. Conventionally, the diffusers

    are applied to multi-stage pumps.

    o The casings can be designed either as solid casings or split casings.

    Solid casingimplies a design in which the entire casing including the discharge nozzle is

    all contained in one casting or fabricated piece. A

    Split casingimplies two or more parts are fastened together. When the casing parts are

    divided by horizontal plane, the casing is described as horizontally split or axially split

    casing. When the split is in a vertical plane perpendicular to the rotation axis, the casing

    is described as vertically split or radially split casing. Casing Wear rings act as the seal

    between the casing and the impeller.

    1.3.2 Rotating Components

    1. Impeller

    The impeller is the main rotating part that provides the centrifugal acceleration to

    the fluid. They are often classified in many ways.

    o Based on major direction of flow in reference to the axis of rotation

    Radial flow Axial flow

    Mixed flow

    o Based on suction type

    Single-suction: Liquid inlet on one side.

    Double-suction: Liquid inlet to the impeller symmetrically from both sides.

    o Based on mechanical construction

    Closed: Shrouds or sidewall enclosing the vanes.

    Open: No shrouds or wall to enclose the vanes.

    Semi-open or vortex type.

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    2. Shaft

    The basic purpose of a centrifugal pump shaft is to transmit the torques encountered

    when starting and during operation while supporting the impeller and other rotating

    parts. It must do this job with a deflection less than the minimum clearance between the

    rotating and stationary parts.

    1.3.3 Auxiliary Components

    Auxiliary components generally include the following piping systems for the

    following services:

    o Seal flushing , cooling , quenching systems

    o Seal drains and vents

    o Bearing lubrication , cooling systems

    o Seal chamber or stuffing box cooling, heating systems

    o Pump pedestal cooling systems

    Auxiliary piping systems include tubing, piping, isolating valves, control valves,

    relief valves, temperature gauges and thermocouples, pressure gauges, sight flow

    indicators, orifices, seal flush coolers, dual seal barrier/buffer fluid reservoirs, and all

    related vents and drains. All auxiliary components shall comply with the requirements as

    per standard codes like API 610 (refinery services), API 682 (shaft sealing systems) etc.

    1.4 WORKING MECHANISM OF A CENTRIFUGAL PUMP

    A centrifugal pump is one of the simplest pieces of equipment in any process

    plant. Its purpose is to convert energy of a prime mover (a electric motor or turbine) first

    into velocity or kinetic energy and then into pressure energy of a fluid that is beingpumped. The energy changes occur by virtue of two main parts of the pump, the impeller

    and the volute or diffuser. The impeller is the rotating part that converts driver energy

    into the kinetic energy. The volute or diffuser is the stationary part that converts the

    kinetic energy into pressure energy.

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    The process liquid enters the suction nozzle and then into eye (center) of a

    revolving device known as an impeller. When the impeller rotates, it spins the liquid

    sitting in the cavities between the vanes outward and provides centrifugal acceleration.

    As liquid leaves the eye of the impeller a low-pressure area is created causing more

    liquid to flow toward the inlet. Because the impeller blades are curved, the fluid is

    pushed in a tangential and radial direction by the centrifugal force. This force acting

    inside the pump is the same one that keeps water inside a bucket that is rotating at the

    end of a string.

    1.4.1 CAVITATION

    Cause:

    i. If suction pressure < Vapour pressure of liquid at operating temperature.

    Formation of vapour bubbles.

    ii. Increase in pressure at volute casing.

    Vapour bubbles collapse.

    Leads to cavitations.

    Remedies:

    i. Maintain Net Positive Suction Head (NPSH) above vapour pressure.

    ii. NPSH = (Total suction head ) (Vapour pressure of liquid @ operating

    pressure )

    1.4.2 EFFICIENCY

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    Actual efficiency:

    Normal efficiency ranges from 60% - 75%.

    Best efficiency ranges from 78% - 80% (up to 89% efficiency in case of horizontal split

    casing pumps).

    Worst efficiency ranges from 30% - 60%.

    1.4.3 Formulae:

    Calculation of efficiency

    1.4.4 PUMPS FORMULAE

    Capacity is directly proportional to the speed of the motor.

    i.e., Capacity RPM.

    Motor head is directly proportional to the square of the speed of the motor.

    i.e., Head (RPM).

    Power is directly proportional to the product of capacity and head of the pump.

    i.e., Power (Capacity Head) (RPM)

    If the RPM is reduced by say by 10%, which will reflect on the

    Capacity reduce by 10 %.

    Head reduce by 19 %.

    Power reduce by 27 %.

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    CHARACTERISTIC CURE OF A PUMP

    1.5 TYPES OF IMPELLER

    SL. NO TYPES FIGURE EFFICIENCY

    1 OPEN BEST 60 %

    2 SEMIOPEN 65 %

    3 CLOSED 80 %

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    BASED ON IMPELLER DIAMETER

    BASED ON SPEED

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    1.6 PUMP CAPACITY CONTROL

    On / Off type.

    Recirculation

    Valves control.

    Pump speed control.

    Mechanical system.

    Electrical system.

    Pump modification.

    Combination of small and big pumps.

    1.6.1 ON / OFF CONTROL

    On/off control is used in many situations where the object is simply to move a

    liquid from point A to point B and the exact pressure or flow rate is unimportant. A

    typical example is the sump pump. The simplest arrangement employs a level switch with

    a very broad dead band. This is used together with a Hand/Off/Auto switch to turn the

    pump on and off. The LSHL contact opens when the level is below its set points. "M"

    represents the motor contactor which energizes the motor whenever the contactor is

    energized. "M" also represents the auxiliary contact that is closed whenever thecontactor is energized.

    If it is important that the level never goes beyond the upper or lower set points, the

    Start/Stop arrangement is preferred. It is illustrated in The process sensing switch has a

    separate output for the upper set point (On) and the lower set point (Off). (Two switches

    may be required.) The manual switch consists of a Start and a Stop button or a combined

    Start/Run/Stop selector with a spring return to centre. The operator may start or stop the

    pump whenever the level is between the two set points. He cannot stop it when the level

    exceeds the high set point unless he locks it out. He cannot start the pump below the low

    set point. A variation of the circuit places the left connection of the start button to the left

    of the low level switch. With this arrangement it is possible to drain a vessel below the

    low set point by holding the start button on. The pump will stop as soon as the button is

    released.

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    With both of these arrangements, there must be sufficient dead band between the high

    and low set points to make certain that the pump does not cycle on and off too rapidly.

    Excessive wear of both the motor and its starter will result if this occurs. Rapid cycling is

    a sign of an over-sized pump.

    1.6.2 SPEED CONTROL

    There is, of course, one other means of adapting a pump to the changing demands

    of the process: Speed control. The virtue of this method is that it reduces the energy input

    to the system instead of dumping the excess. The curves reach all parts of the system

    curve below the full speed curve. Therefore this is an effective means of control. Note,

    however, that these curves have one feature in common with recycle control: At the far

    left end of the system curve the pump curve and the system curve are almost parallel.

    (The particular pump chosen for this example has a rather steeply rising curve near

    shutoff. Most are considerably flatter.) In mathematical terms this means that the

    intersection is poorly defined. In practical terms this means that it is difficult to maintain

    a precise operating point and that control is 'loose' at high turndown.

    In practice, variable speed drives for centrifugal pumps are still relatively uncommon.

    For small pumps the power savings are not significant and for large pumps the

    associated electronics become very expensive. Also, they do not have the high reliabilityof valves. Variable speed steam turbine drives are quite common in the larger

    horsepower ranges. Electric variable speed drives are used in certain specialized

    applications such as pumps that are embedded inside a high pressure vessel. In such

    cases there are no alternatives.

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    1.6.3 COMBINATION OF SMALL AND BIG PUMPS

    a) Parallel pump installation

    Centrifugal pumps are frequently operated in parallel. Their smooth operating

    curve allows this to be done without complication. If it is intended that the pumps are

    usually operated individually and not simultaneously, it is sufficient to have a common

    discharge throttling valve and suction block fire safety valve. However it is essential that

    each have its own recycle arrangements. Do not be swayed by the argument that the two

    pumps will never be run simultaneously. The most obvious reason for simultaneous

    operation is to switch from one to the other so that maintenance can be done without

    shutting down the process. In this case the pump that is being started will be operating

    against a blocked discharge check valve and is in no position to make use of a common

    recycle valve. Remember that the throttling valve is there to serve the process but the

    recycle is there to protect the machine. You don't share seat belts do you?

    Parallel variable speed pumps obviously have individual controls. The most effective

    arrangement is to provide constant flow controls to the majority of the pumps. The set

    points should be at the peak efficiency for each individual pump. The remaining pump

    should have its controller set to handle the swings. Note that is meaningless to have two

    pumps each on pressure control pumping into the same header. They will not share the

    load.

    b) Series pump installation

    Sometimes centrifugal pumps are operated in series. The usual situation is when

    a multistage pump has an NPSHR greater than what is available. In such a case, a

    single-stage pump with a low NPSHR is used as a booster. This is common with boiler

    feed pumps especially if the pump is drawing hot water whose vapour pressure is already

    elevated.

    Process demand control is applied to the high pressure pump. The booster pump should

    be on discharge pressure control. The author was involved in one situation where oil

    field injection water was drawn from a cistern connected directly to a river. In this case

    the booster pumps were pressure controlled by recycle back to the cistern. This allowed

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    the recycle water to keep the water in the cistern agitated, preventing an accumulation of

    silt.

    It is not unusual for a group of booster pumps in parallel to supply a group of high

    pressure pumps in parallel. In such cases care must be taken to ensure that the various

    operating combinations are matched in capacity.

    Every individual pump in a series installation must have its own minimum flow

    arrangement.

    EFFECT OF VARIOUS CAPACITY CONTROL

    1.7 THROTTLING

    1.7.1 Discharge Throttling

    Since the pump exists to serve the requirements of the process, and one of the

    primary purposes of instrumentation is to adapt the equipment to the process, let us

    consider the pump from the point of view of the process. It can be viewed as a constant

    pressure device with an internal restriction. It is the restriction that gives it the "curve".

    It seems natural to put a valve on the discharge to further restrict the pump. This has the

    effect of rotating the curve of the pump/valve system clockwise around Ppm , as can be

    seen in Figure.

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    The combination of pump and valve will be presented as a "black box" with a single

    characteristic curve which terms the "modified" pump curve.

    The more traditional way of looking at the situation is from the point of view of the pump.

    It sees the process system curve as having rotated counter clockwise around Plm. Figureshows that the flow, Q1 , is the same for both cases. The difference between the two

    pressures is the Delta P across the valve. Since the purpose of the pump is to serve the

    process requirements, and the purpose of the valve is to adapt the pump to the process, it

    makes sense to consider the valve to be part of the pump system and to use the modified

    pump curve rather than the modified system curve in our discussion. In any case it can

    be seen that a discharge valve can be used to achieve any operating point on the system

    curve so long as the point is below the pump curve.

    1.7.2 Suction Throttling

    The second possibility for control using valves is to place the valve in the pump

    suction line. This would have an identical effect on the characteristic curve, but the

    method has a fatal flaw cavitation. Cavitation is a phenomenon that occurs when the

    pressure of a liquid is reduced below its vapour pressure and brought back up above the

    vapour pressure again. Bubbles of vapour form in the liquid and then collapse upon

    arriving at the higher pressure region. The collapse occurs at sonic speed ejecting

    minute jets of extremely high velocity liquid. Wherever these jets impinge on solid

    surface extreme erosion occurs. Over time even the hardest materials will be destroyed.

    Therefore it is of utmost importance that this pressure reduction never occurs. It is

    prevented by having sufficient pressure available at the pump suction so that the

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    pressure drops that occur as the liquid is drawn into the eye of the impeller are at all

    times above the vapour pressure of the liquid at its current temperature.

    An explanation of the term Net Positive Suction Head (NPSH) is in order. This is

    the pressure of the liquid at the pump suction in terms of feet or meters of liquid head

    above the vapour pressure of the liquid. The actual NPSH under operating conditions iscalled NPSHA and the minimum required by the pump to prevent cavitation is called

    NPSHR. Clearly NPSHA must be greater than NPSHR to avoid cavitation. It is safe to

    leave a margin of about one meter.

    These peculiar definitions are very reasonable in terms of the pumps actual

    characteristic but they cause some problems to the controls engineer. It means that the

    gauge pressure equivalent of a given NPSHA is proportional to the density of the liquid

    and is also affected by its temperature. The vapour pressure can rise dramatically as the

    temperature rises. This means that the NPSHA can fall without a noticeable change in

    pressure.

    Anything that would reduce the net positive pressure at the pump inlet below the

    NPSHR must be absolutely avoided. Thus suction throttling is never used to control

    pump flow.

    EFFECT OF VALVE THROTTLING

    Design:

    Capacity -85 lps.Head - 4 ksc.

    Existing - 4.8 ksc.

    Proposed - 3.0 ksc

    kWex - ( 55*48)/(102*0.7) = 37.0 kW

    kWp - (55*30)/(102*0.7) = 23.0 kW.

    Savings - 14 kW.

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    CHAPTER - 2

    CRITICAL PUMPS INSTALLATION AT

    IIL DOLVI

    2.1 BLAST FURNACE WATER SYSTEM

    The water system of Blast furnace is classified into three types.

    1. Soft water closed re-circulating system is provided to cool the furnace components

    I.e. tuyeres, staves, cooling boxes, under hearth and hot blast valves.

    2. Make up water and emergency water supply system are provided to replenish the

    losses in closed cooling system and to maintain interrupted supply of cooling water to the

    blast furnace during emergency.

    3. The industrial water surface cooling system is provided to cool the external surfaceof the hearth and furnace shell.

    2.1.1 CRITICAL PUMPS AT BLAST FURNACE

    Group

    No.

    Quantity

    (No.)

    Capacity

    m3/hr

    Head

    m

    Motor

    RatingkW Location MediumT W S

    I 4 2 2 1800 45 320 PH-1 Soft Water

    II 3 2 1 600 81 200 PH-1 Soft Water

    III 2 1 1 250 65 75 PH-1 Soft Water

    IV 4 3 1 1200 45 180 PH-1Industrial

    Water

    V 2 1 1 900 40 125 PH-3Industrial

    Water

    VI 2 1 1 200 70 75 PH-3Industrial

    Water

    VII 2 1 1 1100 30 125 PH-3Industrial

    Water

    X 2 1 1 150 85 55 PH-3Industrial

    Water

    XI 2 1 1 10 60 5.5 PH-2 Soft Water

    XII 2 1 1 100 60 30 PH-2 Soft Water

    XIII 2 1 1 100 80 37 PH-2 Soft Water

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    2.1.2 PROCESS DESCRIPTION GR-1 CIRCUIT

    1. Gr-1 Circuit supplying the soft water to Blast Furnace cooling element namely under

    hearth, staves, B1,B2,C1,C2,C3 ,BLT power pack, under Burdon probe & overburden

    probe.

    2. Group-1 circuit consist of 3 electrical motor driven pumps & 2 Engine operated

    pumps of capacity 1800 m3/hr & head- 45 mtr each.

    3. Normally 2 pumps are running 1 on MSEB power & 1 on 11.81 DG power in auto

    mode. Third pump is on auto stand by mode & comes in operation either of the pump

    trips.

    4. Hot return water from the Blast Furnace cooling members first pass through the Air

    Water Heat Exchanger. Parts of the flow pass through the Plate Heat exchanger for

    further cooling.

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    5. Make up to the Gr-1 closed circuit given through the 2 nos. of expansion tank of

    capacity 39 m3 each from Gr-XI or Gr-XII depending upon the expansion tank level

    limits in the pump suction line.

    6. Gr-1 circuit is also connected with the emergency overhead tank of capacity -550 m3.

    In case of power failure Gr-1 circuit is charged via FSV supply & return.

    2.1.3 PROCESS GROUP II AND III CIRCUIT

    2.1.3.1 PROCESS GROUP II CIRCUIT

    1. Gr-2 Circuit supplying the soft water to Tuyere, Tuyere cooler and Blast Furnace

    cooling element namely0th row cooling box and cigar coolers.

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    2. Group-2 circuit consist of 3 electrical motor driven pumps & 1 Engine operated

    pumps of capacity 600 m3/hr & head- 81 mtr each.

    3. Normally 2 pumps are running 1 on MSEB power & 1 on 11.81 DG power in

    auto mode. Third pump is on auto stand by mode & comes in operation either of

    the pump trips.

    4. Hot return water from the Blast Furnace cooling members passes through Plate

    Heat exchanger for cooling and recycling back to cooling elements.

    5. Make up soft water to Gr-2 closed circuit given through the 1 nos. of expansion

    tank of capacity 20 m3 automatically from Gr.1 circuit to maintain expansion

    tank level from 70-80%.

    6. Gr-2 circuit is also connected with the emergency overhead tank of capacity -550

    m3. In case of power failure Gr-2 circuit is charged via FSV supply & return

    2.1.3.2 PROCESS GROUP III CIRCUIT

    1. Gr-3 Circuit supplying the soft water to Hot Blast Valve Cooling circuit.

    2. Group-3 circuit consist of 2 electrical motor driven pumps & 1 Engine operated

    pumps of capacity 250 m3/hr & head- 65 mtr each.

    3. Normally 1 pump is running on 11.81 DG power in auto mode. 2nd pump is on

    auto stand by mode & comes in operation if the pump trips.

    4. Hot return water from the Hot Blast Valves cooling system passes through Plate

    Heat exchanger for cooling and recycling back to system.

    5. Make up soft water to Gr-3 closed circuit given through the 1 nos. of expansion

    tank of capacity 10 m3 automatically from Gr.1 circuit to maintain expansion tank

    level from 70-80% .

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    6. Gr-3 circuit is also connected with the emergency overhead tank of capacity -550

    m3. In case of power failure Gr-3 circuit is charged via FSV supply & return

    2.1.4 PROCESS GROUP - IV CIRCUIT

    1. 1. Gr-4 Circuit supplying the industrial water to Plate Heat Exchangers of Gr1,2

    &3, Blower House, Mudgun & drilling m/c hydraulics, Compressors and Gas

    expansion turbine for cooling.

    2. Group-4 circuit consist of 4 electrical motor driven pumps & 1 Engine operated

    pumps of capacity 1200 m3/hr & head- 45 mtr each.

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    3. Normally 3 pumps are running, 1 on MSEB power & 2 on 11.81 DG power in

    auto mode. Fourth pump is on auto stand by mode & comes in operation either of

    the pump trips.

    4. Hot return water from the process passes through Cooling tower -1 where it

    cools to 34 degC and reclining back to process .

    5. Cooling Tower-1 has 3 cells of capacity 1500 m3/hr each.

    6. Gr-4 circuit is also connected with side stream filters- 2nos of capacity 160 m3/hr

    each & 3 nos. of automatic self cleaning strainers which improve the quality of

    water

    2.1.5 BLAST FURNACE EXTERNAL SPRAY (PH 3) SYSTEM

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    2.1.5.1 PROCESS V, VI, VII, VIII, AND X CIRCUIT

    1. Gr-7 Circuit re-circulate the hot return industrial water from the furnace external

    spray to Cooling tower-2 where it cools & collected in PH-3 cold well of Group 5,6,7 &

    10.

    2. Group-7 circuit consist of 2 pumps, 2 electrical motor driven pump of capacity 1100

    m3/hr & head- 30 mtr each.

    3. Cooling Tower-2 has 2 cells of capacity 900 m3/hr each.

    4. Gr-5 circuit supply cooling water for Blast Furnace external spray, zeroth row spray

    cooling, tuyere half round spray cooling, hearth spray ring & under hearth spray

    cooling.

    5. Group-5 circuit consist of 2 pumps, 2 electrical motor driven pump of capacity 900

    m3/hr & head- 40 mtr each

    6. Gr-6 circuit supply cooling water for Blast Furnace external stack spray at B-1 & B-2

    zone. Group-6 circuit consist of 2 pumps, 2 electrical motor driven pump of capacity200 m3/hr & head- 70 mtr each.

    7. Gr-10 circuit supply cooling water for Blast Furnace top injection. Group-10 circuit

    consist of 2 pumps, 2 electrical motor driven pump of capacity 150 m3/hr & head- 85

    mtr each.

    2.2 EMERGENCY PROCEDURE DURING POWER FAILURE

    2.2.1 POWER FAILS

    Action To Be Taken

    1. Ensure from the control room that the supply & return emergency valves of the circuit

    should be open.

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    2. Ensure the one pump of Gr. I, II, III, IV, V & VII on 11.81 MW DG power is running.

    OR

    3. Ensure the DG pump set of Gr. I, II & IV running on auto mode if not start the pump

    manually. OR

    4. Call electrical person to start the DG for supplying the emergency power to one pump

    of each group.

    a. Start at least one pump of group II; III & IV in pump house 1 & stop DG

    pump set of Gr. II, III & IV.

    b. Start at least one pump of group VII & V in pump house 3.

    5. After starting the pumps ensure from the control room that the supply & returnemergency valves of the emergency circuit are closed.

    6. Emergency power to be given to the one pump of group XI,XII & XIII.

    7. If exp. tank overflows then action to be taken as per the point no.B.

    8. If exp. Tank level goes very low (0%) then action to be taken as per the point noC.

    9. Monitor the level of the emergency overhead tank & fill up the tank by starting group

    XIII pump if required.

    2.2.2 EXPANSION TANK OVERFLOWS THROUGH SAFETY VALVE

    Action To Be Taken

    1. Close the manual valve of group II & III of soft water make up line to the expansion

    tank.

    2. Stop the group XI & XII pump if it is running. At the same time ensure that group I

    expansion tank are full (80%) from control room.

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    3. Start the draining of expansion tank upto 80% level from vent valve given at the

    expansion tank.

    4. Ask instrument dept. to flush the instrument pipeline near the exp. Tank.

    5. Monitor the tank level from the control room until the system gets stabilized.

    2.2.3 EXPANSION TANK LEVEL GOES VERY LOW (0%)

    Action To Be Taken

    1. Close the isolation valve of nitrogen pipeline of exp. Tank.

    2. Open the vent valve at the expansion tank for venting out the nitrogen

    3. Start the one pump of group XI or group XII for filling the exp. Tank monitor the exp.

    Tank level through control room.

    4. Ensure from the control room that the supply & return emergency valves of emergency

    circuit is closed.

    5. Open the vent valves of system to vent out the entrapped air from the closed circuit.

    6. Once the exp. Tank level reaches to 80% open the isolation valve of nitrogen to

    pressurize the exp. Tank.

    7. Monitor the tank level from the control room until the system gets stabilized.

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    2.2.4 RESPONSIBILITY DURING POWER FAILURE

    Sr.NoAction to be taken Responsibility

    1 Ensure from the control room that the EOHT

    valves have got opened for Gr 1,2 and 3

    Shift engineer 01

    (Shift In-charge)

    2 Transfer the tuyere on Group 5 to Group 2 Shift technician 01

    3 Open Nitrogen to PW Gear box. Shift technician 02

    4 Check from the control room whether GSSV of

    the stove which was on gas cycle at the time ofpower failure has got closed or not, if not close it

    manually.

    Shift engineer 02

    5 Blower house engineer to ensure Emergency

    diesel Blower has started.

    Blower house

    engineer

    6 Check whether one power source (DG/MESB) is

    available for water pumps.

    Shift engineer 01

    7 Check whether emergency DG Pumps havestarted. If not, start manually.

    Shift engineer 01

    8 Connect High pressure Nitrogen line to casthouse air buffer vessel ( Isolate the air vessel

    from the grid) for Drill machine operation.

    Shift engineer 02

    9 Confirm from the safety person that the engine

    operated fire water pump has been started

    Shift engineer 01

    10 Monitor the externally cooled parts of thefurnace; provide fire-fighting water if required.

    Shift engineer 02

    2.3 CRITICAL SYSTEM AT CSP AND MILL UTILITY

    CSP Utility mainly consist two types of cooling system which used to extract

    heat from Steel and Different auxiliaries during the steel making process at Caster and

    Mill Plants.

    Details of cooling system:

    Indirect Cooling System

    Direct Cooling System

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    2.3.1 INDIRECT COOLING SYSTEM

    In steel making process at Caster plant the hot molten metal is poured in mould

    to get hot rolled coils. During this process the temperature of mould and other

    auxiliaries raised beyond the metallurgical limit which may damage the

    equipments.

    For extracting heat indirect cooling water pump supply the water to heat

    exchanger and water jackets of different machines in closed loop system.

    As per the plant water requirement Indirect cooling system divided in four

    streams:

    1. Side Stream Pressure Filter(IC-1)

    2. Caster Machine Cooling(IC-2)

    3. Tunnel furnace Roll Cooling(IC-3)

    4. HSM Auxiliary cooling(IC-4)

    5. Secondary Mould Heat Exchanger(IC-5)

    Specification of Pumps

    PUMP

    NAME

    Quantity

    (No.)

    Capacity

    m3/hr

    Head

    m

    Motor

    Rating

    kW

    LocationMedium

    T W S

    IC 1 2 1 1 500 25 55 CT-2Industrial

    Water

    IC 2 3 3 0 325 80 110 CT-2Industrial

    Water

    IC 3 3 2 1 360 45 75 CT-2Industrial

    Water

    IC4 2 1 1 1200 60 310 CT-2Industrial

    Water

    IC 5 3 2 1 1120 45 20 CT-2Industrial

    Water

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    CSP UTILITY ICW SYSTEM LAYOUT

    2.3.2 DIRECT COOLING SYSTEM

    As the name indicates in this system water is directly comes in contact with hot

    rolled coils which extract heat from hot rolled coils and also gives a better

    surface finish by removing unwanted scale from surface of the coils which is

    known as de-scaling process.

    In DC cooling water system because of direct contact of water with hot rolled

    coils water carries huge quantity of scale which is to be removed before entering

    the cooling tower.

    For removal of scale from water the scale pit vertical turbine pump passes the

    water through seventeen number of Pressure filter arranged in between the

    processes and cooling tower .

    This DC System also divided into 4 steams which as follows :-.

    a) Caster Spray (DC-1)

    b) Mill Roll Cooling (DC-2)

    c) Mill De-scalier (DC-3)

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    d) Laminar Cooling (DC-4)

    Specification Of Pumps

    PUMP

    NAME

    Quantity

    (No.)

    Capac

    ity

    m3/hr

    Head

    M

    Motor

    Rating

    kW

    Locati

    onMedium

    T W S

    DC1

    ABC3 2 1 665 160 450 CT-1

    Industrial

    Water

    DC1 DE 2 2 0 360 160 270 CT-1Industrial

    Water

    DC 2 5 3 2 1300 115 630 CT-1Industrial

    Water

    DC 3 2 1 1 930 56 215 CT-1Industrial

    Water

    DC 4 2 1 1 2100 20 200 CT-1Industrial

    Water

    DC 2& 3R 3 2 1 2900 40 440 sp-1 Slurrywater

    DC1

    RA,RB,

    RC

    3 2 1 665 45 132 sp-3Slurry

    water

    DC1 RD 1 1 0 360 45 75 sp-3Slurry

    water

    DC4

    RA,RB2 1 1 2050 25 210 sp-2

    Slurry

    water

    DC 4

    RC,RD2 1 1 2250 40 340 sp-2

    Slurry

    water

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    CSP UTILITY DCW SYSTEM LAYOUT

    2.4 CRITICAL SYSTEM AT SMS UTILITY

    Basic function of water system is to remove heat generated by the steel making

    process in Steel Melting shop.

    SMS Utility mainly consist following types of cooling system

    1. EAF soft water closed circuit.

    2. EAF DM water closed circuit.

    3. GCP SOFT water closed circuit.

    4. SECONDARY COOLING circuit (COOLING TOWER).

    Specification of Critical Pumps at SMS

    30

    C A P A C I T YH E A D M O T O R

    T O T A W S / B C U M /H RM W C K W

    P -0 1 A ,B ,C 3 2 1 2 1 50 5 6 4 80 P H A S E 1 R C P H 1S O FT W A T

    P -0 2 A , B 2 1 1 60 1 0 0 3 7 P H A S E 1 R C P H 1D M W A T E R

    P -0 2 C , D 2 1 1 60 1 0 0 3 7 P H A S E 1 R C P H 1D M W A T E R

    P -0 3 A , B 2 1 1 4 3 0 5 6 1 10 P H A S E 1 R C P H 1D M W A T E R

    P -0 4 A , B 2 1 1 4 0 0 4 0 7 5 P H A S E 1 R C P H 1S O FT W A T

    P -0 4 C 1 1 0 4 0 0 4 0 7 5 P H A S E 1 R C P H 1S O FT W A T

    P -0 4 D 1 1 0 5 5 0 5 0 1 10 P H A S E 1 R C P H 1S O FT W A T

    P -1 9 A , B , C , D ,E 5 3 2 1 8 00 3 5 2 38 P H A S E 1 R C P H 1S O FT W A T

    P -1 5 A ,B ,C 3 1 2 4 3 00 3 3 5 50 P H A S E 1 R C P H 2R A W W A T

    P -1 7 A , B 2 1 1 6 0 0 2 0 5 5 P H A S E 1 R C P H 2R A W W A T

    P -1 0 A ,B ,C 3 2 1 5 0 0 5 5 1 25 P H A S E 1 R C P H 2R A W W A T

    P -1 2 A , B 2 1 1 1 3 0 5 5 3 7 P H A S E 1 R C P H 2S O FT W A T

    C N T G 1 ,2 2 1 1 9 0 0 4 0 1 25 S IP R ES E R V O IRR A W W A T

    P - 1 0 1 A , B , C , D , E ,F6 3 3 1 6 00 4 0 3 75 P H A S E 2 R C P H 1S O FT W A T

    P -1 0 3 A ,B 2 1 1 5 2 5 6 0 1 50 P H A S E 2 R C P H 1D M W A T E R

    P -1 1 0 A ,B ,C 3 1 2 6 2 00 2 4 7 00 P H A S E 2 R C P H 1R A W W A T

    P -1 1 2 A ,B 2 1 1 8 0 0 3 3 1 10 P H A S E 2 R C P H 1R A W W A T

    P - 1 1 4 A , B , C , D , E ,F6 3 3 1 8 00 3 5 2 40 P H A S E 2 R C P H 1S O FT W A T

    D E S I G N A T I OQ U A N T I T Y

    L oc a tio n M e d i u m

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    2.4.1 EAF SOFT water cooling system

    SMS soft water system is designed to extract heat generated during steel making

    process. Medium for heat removal is soft Water and soft water will remove heat

    from Shell panels, Roof Panels and Elbow.

    Heated soft water will then be cooled in plate type heat exchangers by raw

    water and is re-circulated in the system (closed re-circulation)

    EAF SOFT WATER COOLING SYSTEM

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    2.4.2 EAF DM water cooling system

    Basic function of SMS DM Water system is to remove heat from current carrying

    parts, electrode arms transformer and to cool top lances of Shell no 1,2 and Shell

    3,4.

    Medium for heat removal is De-mineralized water and DM Water will remove

    heat from current carrying parts, electrode Arms transformer and top lances.

    Heated DM water will then be cooled in plate type heat exchangers by raw water

    and is re-circulated in the system (closed recirculation)

    EAF DM WATER COOLING SYSTEM

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    2.4.3 SECONDARY raw water cooling system

    Basic function of secondary cooling water is to remove heat of DM water & Soft

    Water of SMS in plate type heat exchangers by raw water.

    Raw water is Cooled in cooling tower and re-circulated (open recirculation)

    SECONDARY RAW WATER COOLING SYSTEM

    2.4.4 GCP SOFT water system

    Basic function of GCP soft water system is to remove heat generated by the steel

    making process from gases evolved due to process.

    GCP soft water system is designed to extract heat generated during steel making

    process. Medium for heat removal is soft Water and soft water will remove heat

    from water cooled ducts.

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    Heated soft water will then be cooled in Fin fan coolers. (closed recirculation)

    GCP SOFT WATER SYSTEM

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