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Framo Cargo Pumps
No. 1000-0121-401Rev.C 14Oct10/AGAa
Operation manual
SD100SD125SD150
SD200SD250SD300SD350
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Framo Cargo Pumps
OPERATION MANUAL
No.Date/Sign.:Page:Rev. C:
1000-0121-40108Jun98/AGAa2 of 2014Oct10/AGAa
CONTENTS
1 GENERAL DESCRIPTION ....................................................................................................... 2 1.1 Top plate ........................................................................................................................ 2 1.2 Pipe stack ...................................................................................................................... 2
1.3 Pump head .................................................................................................................... 2
2 OPERATING INFORMATION .................................................................................................. 4 2.1 Discharging .................................................................................................................... 4 2.2 Running of pumps in parallel ......................................................................................... 6
2.3 Stripping ........................................................................................................................ 8 2.4 Purging of cofferdam ................................................................................................... 11 2.5 Precautions to be taken when handling special types of cargoes ............................... 14
2.6 Tank cleaning / cleaning of pump ................................................................................ 15 2.7 Precautions if using cargo pumps in sea water ........................................................... 16
2.8 Loading of cargo tank .................................................................................................. 17
3 MAINTENANCE INFORMATION ........................................................................................... 18
4 TROUBLE SHOOTING........................................................................................................... 18
Reference to associated instructions1000-0109-4: Interchange of pump control valve1375-0027-4: Service manual for Pump control valve (STC)
1 GENERAL DESCRIPTION The Framo cargo pump is a hydraulically driven single stage centrifugal pump – with parts exposed tocargo in stainless steel as standard material. The pump is installed in the cargo tank with suction inletat the bottom of the tank.
1.1 Top plate The cargo pump is supported by a deck trunk welded to the deck. All the connections are at the topcover plate, to which the pump control valve STC (Speed Torque Controller) is also mounted. Thiscontrol valve for remote and local operation of the cargo pump regulates the inlet pressure to thehydraulic motor. Thereby the pump speed can be regulated step less from 0 – to max. speed.
1.2 Pipe stack The pipe stack connects the pump head to the top plate by a cargo pipe and a hydraulic section. Inaddition the stripping pipe, the check pipe and eventually temp. sensor pocket and vacuum drain pipe
are integrated in the pipe stack.
1.3 Pump headThe pump head is welded or flanged to the pipe stack/casing and supported by the bottom support.The hydr. motor is located inside the pump head and surrounded by low pressure hydraulic oil.The short shaft, supported by bearings lubricated by hydraulic oil, is connected to a single-stageimpeller. The hydraulic section is surrounded by a cofferdam that completely segregates the hydraulicoil from the cargo. Leakages to the cofferdam chamber will be purged through the cofferdam checkpipe and collected in the exhaust trap when cofferdam is purged.The seal arrangement consists of a mechanical oil seal, single cofferdam lip seal and a cargo seal.The cargo seal is only exposed to static head from the cargo.
The backstop unit installed on the shaft enables the pump to be used as a drop line.Wear rings are fitted between the impeller and the volute casing.
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Impeller
Bearings
Mechanicaloil seal
Cargo seal set
Wear rings
Volute casing
Back stop unit
Hydraulic motor
Cofferdamsurroundinghydraulic section
Cofferdam check pipe
Hydraulic Pipestack
Cofferdam pipe
Hydraulic pressure pipe
Hydraulic return pipe
Cargo stripping pipe
Cargo pipe
Flexible suspension
Exhaust trap
Cargopurging valve
Local control valve
Manometer
Pump control valve (STC)
Cofferdam purging connection Stripping valve
CargoDischarge valve
Deck trunk
Top plate
Fig. 1
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OPEN
Operation of pump from local control valve:
1) Open local control valve (by turning counterclockwise). Cargo discharge valve must be inclosed position.
HP service valve, OPENOnly to be closed when carryingout service work on the pump.
Stripping valve, CLOSED
Cargo discharge valve, CLOSED
Local controlvalve, OPENED
Cargo purging valveCLOSED(Purging hose disconnected)
2) Set the remote controlhandle in maximum position.(Remote control closed)
3) Start the pump byclosing the localcontrol valve(turn clockwise)
and let it run withhydraulic motorpressure 50 barfor approx. 1 minute.
4) Increase hydraulic motor pressure (turn thelocal control valve clockwise) until the cargodischarge pressure is above cargo manifoldpressure.
Manifold pressure Discharge pressure
5) Open cargodischarge valve
6) Increase hydraulic motor pressure untilrequired discharge pressure or capacity isachieved.
7) End of discharging When the tank is close to empty reducepumping capacity to avoid loss of suction.This is indicated by a hunting hydraulicpressure, and should be avoided. Empty thecargo tank at reduced hydraulic motorpressure.
bar 0
100
200
300
400
Reduced capacity
8) When the cargo tank is empty the hydraulicmotor pressure will drop. Close cargodischarge valve and stop the pump by opening
the local control valve (by turning counterclockwise).
Open localcontrol valve
CLOSE
9) Reset for remote cont roloperation:Set the remote controlhandle in minimumposition (remote controlopen) and close thelocal control valve.
10) If the pump is to be restarted, relievethe vacuum in pump cargo pipe asdescribed in chapter 2.3, Stripping(page 9).
bar 0
100
200
300
400
300
225
150
75
0BAR
1P
ON
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300
225
150
75
0BAR
1P
ON
Manifoldpressure
Dischargepressure
2.2 Running of pumps in parallel
This is a general description for running pumpsin parallel.
1) Local control valve and cargo discharge valvemust be in closed position.
Local controlvalve, CLOSED
HP service valve, OPENOnly to be closed when carryingout service work on the pump.
Stripping valve, CLOSED
Cargo discharge valve, CLOSED
Cargo purging valveCLOSED(Purging hose disconnected)
2) Start the hydraulicsystem and set thesystem pressure toabout 100-150 bar.(Depending on pipingsystem, cargo sp.gr.,visc. etc.)
Also see performance diagram for actual pump.
3) Start the first pump andlet it run with hydraulicmotor pressure at approx.50 bar for1 minute.
4) Increase hydraulicmotor pressureuntil the cargodischargepressure is abovecargo manifoldpressure.(Ref.fig. 31 pos. A)
5) Open cargo dischargevalve.
(Ref. fig 31, pos. A-B)
6) Start offloading and raise the hydraulicmotor pressure command to maximum(fig.31, pos C).
300
225
150
75
0BAR
1P
ON
Manifold pressure
Discharge pressureNote!
Handle inmaximum
position.
7) Start the secondcargo pump againstclosed cargodischarge valve asdescribed in step 3.
8) Check that pump discharge pressure ishigher than manifold pressure. If necessaryadjust the motor pressure until the cargodischarge pressure is just above cargomanifold pressure and then open cargodischarge valve.
300
225
150
75
0BAR
2P
ON
Manifold pressure Dischargepressure
Note!Handle inmaximumposition.
9) Start offloading and raise the hydraulic motorpressure command to maximum (the handlein maximum position).Verify that the ullage in the tank is increasing.
SYSTEM PRESSURE
0
100 300
200
400
bar
PRESSURE SET
300
225
150
75
0BAR
1P
ON
Start
OPEN
300
225
150
75
0BAR
2P
ON
Start
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Pressure lossdischarge system
100%25%0 75%50% 125%
Flow Q
H e a d H
50%
0
100%
75%
25%
125%
20% dp
40% dp
60% dp
80% dp100% dp
A
B C
A)
A-B)
C)
D)
E)
F)
G-I)
Increase hydraulic motor pressure.Cargo discharge valve closed.
Open cargo discharge valve.
Increase hydraulic motor pressure.
Open cargo discharge valve - 2 pumps.
Open cargo discharge valve - 3 pumps.
Open cargo discharge valve - 4 pumps.
Increase hydraulic system pressure(4 pumps running).
100%25%0 75%50% 125%
Flow Q
H e a d H
50%
0
100%
75%
25%
125%
A
B C D EF
G
H
I
Pressure lossdischarge system
Typical capacity/head diagramfor cargo pump runningone
Typical capacity/head diagram for cargo pumps runningfour
Fig. 31
10) Start the next pumps, one by one, followingthe same procedure, ref. fig. 31 pos. E-F.Ensure that enough hydraulic power isavailable for the pumps to be run in parallel.
11) Increase the hydraulic system pressure untilrequired discharge pressure or capacity isachieved, ref. fig. 31 pos G-H-I.
12) During parallel pumping with differences intank ullage and pressure losses in deckpiping – it is sometimes required to readjustthe hydraulic motor pressure on some of thecargo pumps to adjust individual capacities.
Discharge pressure
SYSTEM PRESSURE
0
100 300
200
400
bar
300
225
150
75
0BAR
4P
ON
300
225
150
75
0BAR
3P
ON
300
225
150
75
0BAR
2P
ON
300
225
150
75
0BAR
1P
ON
Manifold pressure
13) When a cargo tank becomes empty, closethe cargo discharge valve and stop thepump (handle in minimum position).
300
225
150
75
0BAR
1P
ON
Stop
14) If the pump is to be restarted, relieve thevacuum in pump cargo pipe as describedin chapter 2.3, Stripping (page 9).
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2.3 Stripping
Stripping is to remove remaining cargo in pump cargopipe upon completion of the discharge operation.
The stripping is done by running the pump locally atreduced hydraulic motor pressure against closeddischarge valve while purging the pump cargo pipe.The remaining cargo is then purged into the deck linethrough the stripping valve.
The pump impeller acts as a non-return valve,preventing cargo from returning to tank. If the pumpspeed (hydraulic motor pressure) is too low, cargo willflow through the impeller back to the tank.
The arrangement of deck piping must be taken into
consideration when stripping. Optimal procedure fortank stripping to be based on experience on board.
The best stripping result is obtained when strippingagainst lowest possible backpressure. At increasedback pressure cargo flow is reduced, and stripping timeis increased. High cargo viscosity will also increasestripping time.
Examples:Purging press. - Static head - Back press. = Available purging
pressure
I 7 bar - 2 bar - 0 bar = 5 barII 7 bar - 2 bar - 3 bar = 2 bar
0
1
2
3
4
5
6
7
8Pressure (bar)
Flow
Purgingmediumpressure
Reduced stripping flow atincreased back pressure
Stripping flow atmin. back pressure
Static headStatic head
Backpressure
Availablepurgingpressure
Availablepurgingpressure
Fig. 33
Estimated time to empty the pump cargo pipe(Backpressure 0 bar(g), 1cSt, spgr. 1.0) *
SD100 / SD125 / SD150 2 – 4 min.
SD200 / SD300 4 – 7 min
SD350 8 – 9 min
* Time will be influenced by pump length, back pressure, piping system, type of suction well, cargo,purging medium pressure etc.
Minimum required hydraulic pressure to prevent
backflow through impeller
0
2
4
6
8
60 80 100 120
Hydr. motor pressure (bar)
P u r g i n g m e d i u m p
r e s s u
r e
i n c a r g o p i p e ( b a r g )
Fig. 32
Statichead
Stripping pipe
Pumpcargo pipe
Strippingvalve (C)
Cargo dischargevalve (D)
Cargo deck lineback pressure
Purging mediumpressure
Local
control valve
Cargo purging valve/connection (B)
Purgingmediumsupply (A)
Fig. 34
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Stripping procedure
Relieving vacuum in pump cargo pipe
Stripping
Note!
Open stripping valve (C)
Open cargo purging valve (B) to start the stripping.
Continue stripping until pump cargo pipe is empty, identified by frequent speed variationsof pump.
Close stripping valve (C) and valve at cargo purging connection (B).
Stop the cargo pump.
If necessary, purge the cargo deck line and repeat the stripping sequence.
Close valve (A) and disconnect purging medium hose.
Do not run the pump unnecessary during stripping.
8)
9)
10)
11)
12)
13)
14)
Purging of cargo deck line
Purging
mediumsupplyOPEN
OPEN
CLOSED
CLOSED
Purge the cargodeck line either to terminal line,slop tank or other cargo tankin accordance withships procedure.
Close the manifoldvalve.
5)
Relieving deck line pressure
CLOSED
CLOSED
C OPEN/CLOSE
B CLOSED
CLOSED
Relieve the deckline pressure intothe tank by openand closestripping valve (C).
6)
Note!
Start the pump by using the local control valve, andincrease hydraulic pump pressure to 90-120 bar.
Optimum hydraulic pressure depends on cargo specificgravity and viscosity, purging medium pressure, statichead etc., and must be based on experience on board.
7)
Alternatively the pump can be stripped into a slop tank through a dedicated deck line.
It is also possible to strip to a cargo deck line at low manifold pressure, however stripping time will increase with increased cargo pressure.
A
Pump running
Purgingmediumsupply
CLOSED
CLOSED
CLOSED
C OPEN
A
B
Purgingmediumsupply
D CLOSED
A
B
Pumpstopped
Connect purging hoseto the purging mediumsupply (A) and cargopurging valve (B).
Relieve vacuum inpump cargo pipe byopening valves atpurging medium supply(valve A and B).
Close the cargo purgingvalve (B).
Note!Purging mediumpressure in the hosemust always behigher than thepressure in thecargo pipe.
2)
3)
4)
Preparations
When the tank isempty, close cargodischarge valve(D)and stop the pump.
1)
Fig. 35
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Water test procedure according to Marpol Annex II
Ensure that the cargo tank to be tested and itsassociated piping have been cleaned and thatthe cargo tank is safe for entry.
Provide 100kPa (1 atmosphere) backpressure at the cargo tank’s unloadingmanifold, see fig. 36.
- Fill the cargo tank with water to a depth necessary to carry out normal end of discharge operation.Water test with sea water must be followed by a thoroughly rinse with fresh water to remove
chlorides.
- Purge and relieve pressure in cargo piping according to “Stripping procedure” step 1 to 6.
- Follow the normal stripping procedure.Start timing when cargo purging valve is opened, ref. step 9. Stop timing when stripping valveis closed, ref. step 11.
- The time taken to be recorded.
- Residues to be collected and measured.
Note! Residues in cargo deck line to be measured separately.
Log the results
Tank noResidues (liter)
In suction well On tank topDuration (sec)
Water residuesin tank after water test.
Fig. 37
10m
Cargo piping
Manifoldvalve
Test hoseMin. Ø75mm
Fig. 36 Suggested back pressure manifold arrangement
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2.4 Purging of cof ferdam
This procedure describes purging of submerged cargopumps with «dry» cofferdam. (For submerged cargo pumps
with liquid filled cofferdam, refer to instruction 1000-0102-4.)
The cargo pump cofferdam is essential for segregation of thepump hydraulic section from the cargo – and for sealmonitoring. Purging to be carried out at regular intervals forthe purpose of:
- Leakage rate detection- Condition monitoring of the shaft seal system- Avoid that leakages are blocking the cofferdam
How to purge the cofferdam
CAUTION: Exhaust gas and liquid may be hazardous.Wear safety gear and avoid contact with drain from exhausttrap and venting line.
Preparation:1) Place a suitable container underneath the exhaust trap to
collect the leakage.
2) Check that drain valve at bottom of exhaust trap is notblocked.
3) Drain the purging medium supply line for condensedwater.
4) Connect purging hose (max. supply pressure 7 bar).
Purging:
5) Start the purging by opening the valve at purging mediumsupply line.
Note! A relief valve is fitted at cofferdam purging connection. Thisis set at 3-3,5 bar to limit the purging pressure for protection
of the pump seals. A small leakage from the relief valve isnormal when liquid is purged from cofferdam. The valve willalso open if the cofferdam is blocked.
6) Check that exhaust gas is coming out of the exhaust trapvent line (to verify that cofferdam is open).
CAUTION! Exhaust gas and liquid – watch out !
7) Purge cofferdam in several sequences if required.Drain exhaust trap between each sequence.
8) Disconnect purging hose.
9) Close exhaust trap drain valve.10) Log the amount of leakage, -evaluate the result.
Note! For handling special cargoes, ref. chapter 2.5.
Cofferdam purging connection
Purging medium supply
Exhaust gas
Cofferdamcheck pipe
Container tocollect the leakage
Relief valve
Exhaust trap
CLOSED
CLOSED
Purgingmedium
Flexible hose withsnap-on coupling
Vent. line
Drain valve
CLOSED
CLOSED
Fig. 38
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Purging intervals, - logging of purging result
LOADING VOYAGE DISCHARGE
1. Shortly beforeloading. 1. 1-2 days after loading. 1. Shortly beforedischarging.
2. If no leakage at step 1, purge every fortnight. 2. Shortly afterdischarging.
3. If leakage is detected at step 1, or at a later stageduring the voyage, purge this pump every day.
4. If pumps are used for cargo circulation during thevoyage, the cofferdam must be purged before startand after stop.
Note! Neglecting of purging can result in a blocked cofferdam and lack of leakage control.
The purging form should be filled in with the results from every purging operation. Each horizontalline in the form represents one cargo in one tank from loading till discharging. If a ship loads anddischarges some tanks more frequently than other, an extra form should be filled in for thosetanks.
PURGING ROUTINE FOR FRAMO SUBMERGED CARGO PUMPS
SHIP NAME:__________________________________ VOYAGE NO.: __________________________________Electronic copy: purging@framo.no
If pap er cop y: Frank Mohn Services AS
Ship owner: Electronic/ Paper co py
A B C D
NOTE:
In "Result" column:H= hydr. oilC= cargoW= water condensate In "Open cofferdam" column:Yes = air or liquid coming throughNo = Blocked cofferdam
Shortly
before loading
1-2 da ys
after loading
If no leakage at A go to C.
If leakage at A purge this pumpevery day
Shortly
before unloading
Shortly
after unloading
TankNo.
Cargo Date Result Opencoffer-
dam
Date Result Opencoffer-
dam
Date Result Opencoffer-
dam
Averageresult
Date Result Opencoffer-
dam
Date Result Opencoffer-
dam
State a ction ta ken,new pa rts installed, e tc.
Signed by: Chief Officer Chief Engineer Pump ma n
For long voyages with"no leakage a t A"
purge at least every
fortnight.
Tank no.Type of cargo
Date of purging
Open cofferdam:Yes= air or liquid coming throughNo = blocked cofferdam
Note action taken -new parts installed etc.
RESULT:If no leakage, write OK.If leakage, write amount of leakage in litres andtype of leakage.(Example: 1H= 1 litre hydraulic oil, 1C= 1 litre cargo,1 H/C= 1 litre mixture of hydraulic oil and cargo).
Fig. 39 Example of FRAMO purging form
Filled in purging form to be sent to Ship owner and to Framo (purging@framo.no).(Green copy for the ship, red copy for the Ship owner and white copy for Framo.)
Ship’s crew to evaluate the purging results and to take necessary action – however in case theship’s crew needs advice, contact a Framo Service Station.
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Evaluation of the purging result
Cargo leakage
A small leakage rate of up to about 0.5 l/day
(and higher with light cargoes) during pumpoperation is normal.
Acceptable leakage rate depends on the type ofcargo and possible consequences in case ofleakage.
- Risk for clogging of pump cofferdam
Cargoes like naphtha, condensate etc.penetrates the shaft seals more easily thanlubricating oils, vegetable oils and other viscouscargoes.
It is therefore recommended to carefully monitorthe leakage rate over a period of time,preferable with different type of cargoes.
For critical cargoes, when the leakage rate isabout 2 litres/day or higher, the pump must bepurged a couple of times daily and service(pressure test-repair) carried out at firstopportunity.
Intensify the purging if the leakage rate isexceeding acceptable limits. If this is not
sufficient to keep the leakage under control itmust, depending on the nature of the cargo, beconsidered to discharge the tank using theportable pump.
Cargo leakage to cofferdam normally indicatesshaft seal leakage. But the leakage might comefrom flange connections or damage (cracks/pinholes) in pump/pipe stack (ref. chapter 4,Trouble shooting).
The development of a cargo leakage can be
monitored if purging is done according toinstructions. Thereby maintenance work can beplanned, and unexpected shut down due toleakage can be avoided.
Hydraulic o il leakage
Hydraulic oil in the cofferdam normally
indicates shaft seal leakage, but might comefrom flange face seals in pipe stack/ pumphead or damage in the pipe stack/pump head.
A small leakage rate into the cofferdam up toabout 10 ml/h (0.25 l/day) from the mechanicaloil seal or lip seal during pump operation isnormal. For short periods of time, higherleakage peaks can occur.
If the leakage rate is increasing aboveacceptable level, the pump must be purged a
couple of times daily and inspected as soonas possible to find the reason for the leakage.Intensify the purging if the leakage rate isincreasing above the acceptable level. If thisis not keeping the leakage under control,close the hydraulic service valve. Dependingof the nature of the cargo consider to use theportable pump to discharge the cargo.
Blocked cofferdam
In general we do not recommend operatingthe cargo pump with blocked cofferdam.For advice, depending of type of cargo etc.,contact a Framo Service Station.
Note! Always remember to pressure test the cofferdam with 3 bar to locate the leakage prior to anydismantling of the cargo pump.
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Liquidsupply
Liquidreturn
CLOSED
CLOSEDCLOSED
Valve for regulation of flow
OPEN
Flexible hose withsnap-on coupling Fig. 41
2.5 Precautions to be taken when handling special types of cargoes
The main rule is to have the cofferdam clean, dry and vented to atmosphere through the exhaust trapvent line, in order to detect leakages easily. However, when handling certain groups of cargoes it may be
an advantage to fill the cofferdam with liquid to improve the seal lifetime and to avoid solidifying cargoblocking the cofferdam. Recommended type of liquid to be filled into the cofferdam for some groups ofcargoes is given below.This is a general advice, only experience can define which liquid gives the best result for the greatnumber of different types of cargoes.
FillingTo fill liquid in the cofferdam, disconnect the
exhaust trap piping from the pump top plate. Usinga suitable adapter, fill the liquid through thecofferdam check pipe. Open the purging connectionto ventilate the cofferdam during filling. (Connect anopen female coupling or similar).
Circulation A circulation of liquid through the cofferdam canbe arranged in the following way:- Connect liquid supply to the purging connection.
The supply line must also be equipped with a
valve to regulate the liquid flow.- Open drain valve on the exhaust trap, and
collect the return liquid here.
Note!When filling or circulating liquid in the cofferdam,it is important that the hydraulic oil return pressurealways is higher than the pressure in the cofferdam.This is especially important on hydraulic systemswith non-pressurised return line.
Solidify ing cargoes (in cargo tanks with heating coils )To prevent the cargo to get solid (freeze) inside the suction well, circulate the cargo at intervals bystarting the cargo pump.
Ac id cargoes After discharging and purging is finished, itmay be an advantage to circulate freshwater through the cofferdam to remove allresidues after a leakage.
Phenol, caustic soda etc. A circulation of hot water through the cofferdamcan avoid clogging.Note! Remember that some of these types of
cargoes are very hazardous.
Polymerising cargoes. (TDI, MDI)
Fill cofferdam with dioctyl phthalate(DOP) tolimit the risk of blocking the cofferdam.
Heated oil products (fuel oil, crude oil)
Fill cofferdam with diesel oil/white spirit to keepany leakage into cofferdam in liquid form. (This isespecially important after stripping and duringtank cleaning.)Crystallizing cargoes (molasses, etc.)
Fill cofferdam with fresh water. Thecofferdam may also be arranged with asmall water circulation.
CLOSED
Vent. line
CLOSED
CLOSED
Open purgingconnection
Fig. 40
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2.8 Loading of cargo tank
In general it is recommended to start the loading slowly to avoid pressure surges in the cargo pipe lineand the pump. Correct operation of valves is important. Open / close valves slowly !
If a separate drop line is installed,it is recommended to load throughthe drop line only.
If required to load through the pump,use following procedure:
Note! For sampling procedures,ref. charterer's requirements.
- Keep manifold valve closed until
the cargo reach the manifold.
- Open manifold valve partly to fillcargo line on deck.
- Open cargo pump discharge valveand drop line valve slowly.
- Open manifold valve slowly untilrequired pressure/capacity is reached.
Note! Maximum acceptable loadingpressure when loading throughthe pump is 8 bar at the pumptop plate.
Cargo line
Cargo discharge valveCLOSED
Drop line
OPEN valve
Loading pressureMax. 8 bar
Fig. 45 Arrangement with separate drop line
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3 MAINTENANCE INFORMATION
Prior to entering a cargo tank for doingservice it is essential to become familiar
with the ship's safety rules andrequirements regarding cargo-handlingequipment. Do not enter a cargo tank beforethe tank is confirmed gas free and safe.Before doing service on pump, always closeand lock the hydraulic pressure inlet valveand purge the cofferdam. Purge cofferdamaccording to chapt.2.4.
Close the cargo discharge valve. Ensurethat the valve is in closed position until thework/service is finished (info sign to be
placed at the control panel/computer).
Caution: Venting gas and liquid may behazardous.
To prevent skidding and minimize the risk offire it is important to remove oil spill duringmaintenance and servicing work. Theoperator should be confident that all flangeconnections are in satisfactory condition soas to prevent hydraulic oil and cargo spills.
4 TROUBLE SHOOTING
Warning: To prevent damage from hazardous cargoes, take necessary precautions, wear safetygear and avoid contact with spray/gases.
Symptom: Possible reason: Remedy: *)
COP operational problem
(First it is necessary to
verify if the problem is inthe pump control system
or in the pump unit itself).
General Ref. system service manual - Trouble shooting
section
The pump will not start a) Cargo pump remote
control system failure
b) Pump control valve
failure
c) Pump impeller stuck.
c1)Frozen /solidified cargo
c2)Foreign objects stuck in
pump or other
mechanical problem
a) Ref. instruction for Pump remote control
b) Ref. Instruction for Pump control valve (STC)
c1) Heat the cargo in the pump suction well.
c2) Pump unit to be inspected.
Pump is vibrating heavily a) Control system problem
b) Rotating parts out of
balance.
a) Ref. instr. for Pump control system.
b) Impurities stuck in impeller or othermechanical problem.
Too low pumping capacity a) Control system problem
b) Worn wear rings.Impurities stuck inimpeller, or othermechanical problem
a) Ref. instr. for Pump control system and instr.for Pump control valve.(If required interchange pump control valveas described in instr. 1000-0109-4)
b) Pump unit to be inspected
*) Ref. instruction for maintenance and repair for actual pump.
8/19/2019 framo operational manual
19/20
Framo Cargo Pumps
OPERATION MANUAL
No.Date/Sign.:Page:Rev. C:
1000-0121-40108Jun98/AGAa19 of 2014Oct10/AGAa
Symptom: Possible reason: Remedy: *)
Noise(non return valve)
and vibration when loadingthrough the pump.
Damaged back stop unit
Check hydraulic motor inlet pressure –
pressure above 15-20 bar indicatesmalfunctioning back stop unit.
Change back stop unit.
Contact a Framo Service Station.
Not possible to purge thecofferdam (no air, inert gasor liquid coming out of thecheck pipe when purging)
(See also chapter 2.4)
a) No or insufficient
purging medium supply
b) Blocked cofferdam
system
Note!
In case steam is used in
attempt to clear a blockage
in pump cofferdam system
pay special attention not to
over pressurize the
pump/pipe stack
a) Check valves, hose connections andpurging medium relief valve (open at approx.3 bar).
b) Check the exhaust trap and the piping ondeck for blockage. Open if possible.
b1) Disconnect check pipe from pump unit(lower seal house) – watch out for possiblepressurized liquid in cofferdam!!By carefully purging check if the blockage islocated in the check pipe or in the pump/pipe stack cofferdam.Depending on the nature of the mediumblocking the cofferdam system use steam orsolvent to dissolve the blockage.Dismantling of pump might be required.
Note! Pressure test pump after assembly.
Cargo leakage to pumpcofferdam.
(See also chapter 2.4)
General
Note! Always pressure test pumpprior to and afterdismantling. This is requiredto locate possible leakageand to confirm no leakageupon completion of repair.
a) Worn cargo seal
Note; If no leakage isdetected by pressure testit is likely that the cargoleakage to cofferdam iscaused by worn cargoseal. (the upper seal lip issealing when pressurizingcofferdam).
b) Leaking seal element inflange connection
c) Crack/pinhole in piping
Pressure test pump cofferdam system at approx.3 bar.Check for leakage – if required spray with soapywater to locate the leakage.
a) Replace cargo seal set.
Also, carefully check ceramic sleeve forpossible damage-wear.
b) Check for loose bolts and for pitting corrosionin seal faces – in case of corrosion repair isrequired.When assemble, renew damaged seal
element.
c) Contact a Framo Service Station.
*) Ref. instruction for maintenance and repair for actual pump.
8/19/2019 framo operational manual
20/20
Framo Cargo Pumps
OPERATION MANUAL
No.Date/Sign.:Page:Rev. C:
1000-0121-40108Jun98/AGAa20 of 2014Oct10/AGAa
Symptom: Possible reason: Remedy: *)
Hydraulic oil leakage to
pump cofferdam.(See also chapter 2.4)
General
a) Leaking shaft seal
b) Leaking seal element in
flange connection.
c)Crack/pinhole in piping
Drain the pump return side prior to dismantling.
Disconnect pump head/unit from pipestack/casing.Pressurize pump unit return side at approx 4 barand check for leakage to cofferdam side.Pressure test pump pipe stack / casing at max 7bar on cofferdam side and check for leakage toreturn side.
a)Replace shaft seal (replaced seal to bereconditioned if feasible)
b) Check sealing surface for possible damage –
repair if damaged.When assemble, renew damaged sealelement.
c) Contact a Framo Service Station.
*) Ref. instruction for maintenance and repair for actual pump.
Note!Evaluate if changed parts as sleeves, mechanical seals etc. are possible to recondition.Send these parts to a Framo Service Station and ask for an evaluation.
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