Wi-propane Storage System
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Transcript of Wi-propane Storage System
Q-SHE WORK INSTRUCTION WORK INSTRUCTION FOR PROPANEGAS STORAGE PLANT
ISO 9001: 2000 ISO 14001: 2004
BS OHSAS 18001:2007
7.5.1 4.4.6 4.4.6DOC NO: CR-UL/05/W PAGE: 1 OF 17 REV. NO.: 01EFF. DATE: 01/09/10
APPROVED BY ISSUED BY
1. Purpose
These working instructions serve as a reference document for operation & maintenance of Propane gas storage plant.
2. Scope
This document covers the operating instructions which are mandatory for
i. Unloading of Propane Gas from mobile tankers to storage tanks
ii. Safe Storage of gas in storage tanks iii. Gas distribution to all the users.Note: For process flow, please refer attached Annexure.
3. Cross Reference Operation & Maintenance manual, Logbooks and checklist.
4. Overall Responsibility HOD
Q-SHE WORK INSTRUCTION WORK INSTRUCTION FOR PROPANEGAS STORAGE PLANT
ISO 9001: 2000
ISO 14001: 2004
BS OHSAS 18001:2007
7.5.1 4.4.6 4.4.6DOC NO: CR-UL/05/W PAGE: 2 OF 17REV. NO.: 01EFF. DATE: 01/09/10
APPROVED BY ISSUED BY
S. No. Activity Responsibility Reference
Document
5 PROCEDURE FOR PROPANE HANDLING
Following precautions have to be taken care of at the time of unloading the gas.
SECURITY GAURD’S INSTRUCTION :
Following particulars to be checked before permitting the tanker to enter the storage area.
Driver has valid Driving License to drive the heavy motor vehicles (HMVs).
Surrender of mobile phone to security check post.
Surrender of any inflammable material (e.g. Match Box, Cigarette Lighter & Cell Torch etc)
DRIVER’S INSTRUCTION (UNDER OPEARTOR SUERVISION):Driver has to ensure followings a) Before entry of the vehicle in storage station
Whether he has adequate PPE’s to keep himself safe in case of any gas leakage.
Whether spark arrestor is fitted on the silencer of the vehicle or not.
b) Prior to switch OFF the vehicle engine & before startup of unloading.
Proper positioning of the vehicle over the hump made on vehicle parking inside storage area.
Wheel chocks are placed in front and back of the rear wheels of the tanker.
Lights and radio (if any the area) are in switched off position.
Section in-charge Operation
manual
Q-SHE WORK INSTRUCTION WORK INSTRUCTION FOR PROPANEGAS STORAGE PLANT
ISO 9001: 2000
ISO 14001: 2004
BS OHSAS 18001:2007
7.5.1 4.4.6 4.4.6DOC NO: CR-UL/05/W PAGE: 3 OF 17REV. NO.: 01EFF. DATE: 01/09/10
APPROVED BY ISSUED BY
S.
No.
Activity Responsibility Reference
Document
5.2
OPERATOR’S INSTRUCTION:
1. General Instructions
Check for any gas leakage from flange joints/ threaded joints of all the pipeline & fittings to be used during unloading
Check decanting hoses for any damage. Do not unload Propane Gas from the tanker
in case of lightening, thunderstorm or gas leakage.
Check electrical connections of pumps and compressor and to keep selector switch to local.
Ensure DCP fire extinguishers are close to the unloading area to avoid/control the unfair in case of fire.
Ensure Fire fighting pipeline, fire hydrants and monitors are pressurized with Standard pressure of 7Kg/Cm2.
Ensure Water sprinkling system is in running condition.
A. Unloading operationPrior to startup of unloading operation
Note down the % age of liquid available in each Propane tanks by magnetic level gauge (may be cross- checked by rotogauge)
Note down temperature of Propane from the thermo dial fitted on the tanks.
Check the Quantity of gas in storage tanks available in the tanks (referring volume v/s
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temperature chart) and estimate the quantity of gas can be filled in each tank.
Q-SHE WORK INSTRUCTION WORK INSTRUCTION FOR PROPANEGAS STORAGE PLANT
ISO 9001: 2000 ISO 14001: 2004
BS OHSAS 18001:2007
7.5.1 4.4.6 4.4.6DOC NO: CR-UL/05/W PAGE: 4 OF 17REV. NO.: 01EFF. DATE: 01/09/10
APPROVED BY ISSUED BY
S. No. Activity Responsibility Reference
Document
Decide that in which tank, this gas (available in the tanker) quantity can be filled.
Note down the pressure (Kg/Cm2 or Psi) of each tanks.
Note down the differential pressure between tanks & tanker.
Drain out liquid moisture from the tank by first opening upper valve fitted on tank drain line and then opening lower valve and closing upper one.
1. Unloading of liquid gas by differential pressure available in tanker & tanks
a. Connection of liquid decanting hosepipe to liquid unloading point on tanker:
i. Ensure isolation valve for liquid unloading point on the tanker are closed.ii. Open the dummy flange of liquid unloading point of tanker by unscrewing the nut of fasteners.iii. Match the flange of unloading point on tanker with flange of liquid decanting hose by holding together and ensuring full penetration of threaded shank of fasteners through holes of matched flanges. This will result in ease of procedure during connection. iv. Put the flinches adjoining the mating flanges and tighten the nut by Ring & DE Spanner (non sparking type only).
b. Connect vapor-decanting hosepipe to
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vapor unloading point on tanker.i. Ensure isolation valve for vapour unloading point on the tanker are closed.
Q-SHE WORK INSTRUCTION WORK INSTRUCTION FOR PROPANEGAS STORAGE PLANT
ISO 9001: 2000 ISO 14001: 2004
BS OHSAS 18001:2007
7.5.1 4.4.6 4.4.6DOC NO: CR-UL/05/W PAGE: 5 OF 17REV. NO: 01EFF. DATE: 01/09/10
APPROVED BY ISSUED BY
S. No. Activity Responsibility Referenc
e
Documen
t
ii. Open the dummy flange of vapor unloading point of tanker by unscrewing the nut of fasteners.
iii. Match the flange of unloading point ontanker with flange of vapour decanting hose by holding together and ensuring full penetration of threaded shank of fasteners through holes of matched flanges. This will result in ease of procedure during connection. iv. Put the flinches adjoining the mating flanges and tighten the nut by Ring & DE Spanner (non sparking type only).
Note down pressure in tank and tanker. If tanker pressure is more than 20 psig than storage tank pressure. Open valve on liquid unloading point on tanker.
Ensure all other valves on the liquid line are closed.
Check gas leakage from flange joints of hose by applying soap solution on joints.
If any bubble formation appears on flange/threaded joints, it confirms the leakage of gas. This must be arrested by tightening the fasteners.
Open isolation valve on liquid unloading
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line of the storage tank to be filled. Ensure the flow of liquid gas by liquid flow
indicator and keep constant watch on the gas flow.
Q-SHE WORK INSTRUCTION WORK INSTRUCTION FOR PROPANEGAS STORAGE PLANT
ISO 9001: 2000
ISO 14001: 2004
BS OHSAS 18001:2007
7.5.1 4.4.6 4.4.6DOC NO: CR-UL/05/W PAGE: 6 OF 17REV. NO: 01EFF. DATE: 01/09/10
APPROVED BY ISSUED BY
S. No. Activity Responsibility Reference
Document
After some time, there would be no more flow of liquid gas due to equal pressure in both tanks and tanker.
Liquid decantation by pump Note: It is a recommended practice to take the unloading pump on line, when the pressure difference is 10/15 psig approximately.
Close the bypass valve of the pump. Open inlet & outlet valves of the pump. Open vapour unloading valve on tanker,
keeping all other valves on the line closed. Check gas leakage from flange joints of
hose by applying soap solution on it. If any bubble formation appears on the
joints, it confirms the leakage of gas. This must be arrested by tightening the fasteners.
Open valve on vapour balance line on the tank to be filled.
Switch on the pump. Monitor the flow of liquid propane through
liquid flow indicator. Always keep watch on level of liquid
propane in the tank through magnetic level
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manual
gauge. Stop the filling operation at the moment
alarm is heard on MCC through level switch.
A metallic sound from the pump will ensure all the liquid has been decanted and liquid flow indicator will not show any flow of gas.
Switch off the pump immediately to avoid dry run.
Close all the valves on liquid inlet line and vapor balance line.
Q-SHE WORK INSTRUCTION WORK INSTRUCTION FOR PROPANEGAS STORAGE PLANT
ISO 9001: 2000
ISO 14001: 2004
BS OHSAS 18001:2007
7.5.1 4.4.6 4.4.6DOC NO: CR-UL/05/W PAGE: 7 OF 17REV. NO: 01EFF. DATE: 01/09/10
APPROVED BY ISSUED BY
S. No. Activity Responsibility Reference
Document
Close the liquid & vapor unloading valve on the tanker.
Open vent valves on liquid & vapour unloading line of tanks and vent out the gas present in the hoses.
Open the mating flanges and disconnect both decanting hoses.
2. Liquid decantation by compressor
Note: It is a recommended practice to take compressor on line, when the pressure difference is 10/15 psig approximately. Primary Check ups:
i. Ensure sufficient level of lubricating oil in crank case of compressor.
ii. Ensure proper Belt tensioning in prime movers of pump to be used for unloading (if any)iii. In case, pressure difference (between tank
& tanker) ≥ 15 psi, open liquid connection valve on the tanker, keeping all other valves on the line closed
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Open liquid inlet valve and Remote Operated Valve ROV (if any) on the tank depending upon which tank has to be loaded.
Open Vapor unloading valve and Remote Operated Valve ROV (if any) of the tanker.
Open isolation valves of vapour balance line
of the tank.
Q-SHE WORK INSTRUCTION WORK INSTRUCTION FOR PROPANEGAS STORAGE PLANT
ISO 9001: 2000 ISO 14001: 2004 BS OHSAS 18001:2007
7.5.1 4.4.6 4.4.6DOC NO: CR-UL/05/W PAGE: 8 OF 17REV. NO: 01EFF. DATE: 01/09/10
APPROVED BY: ISSUED BY
S. No. Activity Responsibility Reference
Document
Ensure the four way valve of the compressor is in correct position. This is required to regulate vapor pressure available in storage tank to tanker.
Ensure compressor bypass valve is closed.
Open inlet valve & outlet valve of the compressor.
Switch on the compressor. Ensure pressure of the lubricant in crank
case of compressor is within the limits i.e. 25 psig.
Check the current drawn by the prime mover of the compressor.
Compressor will suck the vapors from the storage tank, compress it and discharge it to the delivery tank. This creates differential pressure and as a result pushing more liquid in to the tank.
Stop the filling operation at the moment alarm is heard on MCC through level switch.
Keep on checking the liquid level in the tanker by rotogauge.
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When rotogauge fitted on the tanker shows zero reading, & no liquid flow is seen through liquid flow indicator, stop the compressor.
Close the liquid line valve on tank & liquid unloading valve on tanker
Open vent valve on the liquid line & vent out the liquid gas present in the hoses.
Unscrew the nut of fasteners fitted on matched flanges of decanting hose and liquid unloading point on the tanker.
Disconnect the hose and recap it by the dummy flange.
Q-SHE WORK INSTRUCTION WORK INSTRUCTION FOR PROPANEGAS STORAGE PLANT
ISO 9001: 2000 ISO 14001: 2004
BS OHSAS 18001:2007
7.5.1 4.4.6 4.4.6DOC NO: CR-UL/05/W PAGE: 9 OF 17REV. NO: 01EFF. DATE: 01/09/10
APPROVED BY ISSUED BY
S. No. Activity Responsibility Reference
Document
3. Vapor recovery by using compressor: Change the position of ‘four way valve’
to desired position end ensure its right direction.
Open valve on vapor unloading line of tanker.
Open vapor recovery valve on the tank depending up on the tank has to be loaded.
Ensure compressor bypass valve is closed.
Ensure vapor connection valve connecting vapor balance line is closed.
Open inlet valve & outlet valve of the compressor.
Switch on the compressor. Compressor will suck the vapor from the
delivery tank, compress it and discharge it to the storage tank.
The compressor may continue to recovers vapors till the pressure in the tanker falls to 35 psig or so.
Switch off the compressor, as this
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completes the process. Close all the valves on vapor balance
line and vapor recovery line. Close the vapor unloading valve on
tanker. Open vent valve and vent out the gas
present in the hoses. Unscrew/Open the flanges of the hoses
and disconnect the liquid decanting hose.
Drain out moisture/heavy impurities etc. from storage tank through drain valves.
Drain out moisture from the compressor through drain valve.
Unscrew the fasteners and open the flanges of the hoses and disconnect the liquid decanting hoses.
Q-SHE WORK INSTRUCTION WORK INSTRUCTION FOR PROPANEGAS STORAGE PLANT
ISO 9001: 2000 ISO 14001: 2004
BS OHSAS 18001:2007
7.5.1 4.4.6 4.4.6DOC NO: CR-UL/05/W PAGE. 10 OF 17REV. NO. 01EFF. DATE: 01/09/10
APPROVED BY ISSUED BY
S. No. Activity Responsibility Reference
Document
c) After completion of unloading The hoses are disconnected form the
tanker. Wheel chocks and barriers are removed. Earthing connections to the tankers are
removed. Check The level of tanks
PPE’s to Be Used During Handling of Propane Safety Helmet Safety shoes Full face gas mask Tight fitting safety goggles. Protective hand gloves (made of
rubber/leather) impervious to Propane. Protective pants & jackets impervious to
Propane Breathing apparatus in case of any gas
leakage.
B. Gas Storage
Liquid propane stored in the tank has pressure in the range of 8-10 Kg/Cm2.
If ambient temperature is >37°c (mostly in summer season), it’s safe to spray the water over the tanks by sprinkler system. This controls the temperature & pressure of the tanks.
Monitor and record Pressure, temperature and Level of the Storage tank’s every 2 hours.
Section in-
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Q-SHE WORK INSTRUCTION WORK INSTRUCTION FOR PROPANEGAS STORAGE PLANT
ISO 9001: 2000
ISO 14001: 2004 BS OHSAS 18001:2007
7.5.1 4.4.6 4.4.6DOC NO: CR-UL/05/W PAGE: 11 OF 17REV. NO: 01EFF. DATE: 01/09/10
APPROVED BY ISSUED BY
S. No. Activity Responsibility Reference
Document
C. Gas Supply to Process Plants
Generally, gas pressure range at Inlet & Outlet of PRV is about 7-8 Kg/Cm2 & is 1.5-2.5 Kg/Cm2 respectively. i. If pressure of gas at PRV Inlet is 6-7 Kg/Cm2, there is no need to make vapour through vaporizer.ii. When pressure at PRV Inlet is ≤ 4Kg/Cm2, vaporizer has to be started.
Start- up procedure for vaporizer
Cautions prior to startup Ensure that the steam must be dry and
saturated (not superheated or wet) for proper performance of the vaporizer.
Check dry steam pressure (3-4 Kg/Cm2) available at vaporizer inlet.
LPG vapor temp should be kept at or below 150°C.
Start- up procedure for vaporizer
Turn on electricity to the control box. Leave the vaporizer in the ‘off’ position.
Open the vaporizer steam inlet valve. Open the vaporizer steam inlet strainer
blow down valve. Blow the steam pipeline down until no
water is presents it ensures that steam is saturated.
Open the condensate return line when only steam is in the system.
Close the LPG outlet valve of vaporizer.
Section in-charge Operation
manual
Q-SHE WORK INSTRUCTION WORK INSTRUCTION FOR PROPANEGAS STORAGE PLANT
ISO 9001: 2000 ISO 14001: 2004 BS OHSAS 18001:2007
7.5.1 4.4.6 4.4.6DOC NO: CR-UL/05/W PAGE: 12 OF 17REV. NO: 01EFF. DATE: 01/09/10
APPROVED BY ISSUED BY
S. No. Activity Responsibility Reference
Document
Open all valves of liquid gas pipeline from LPG tank to the vaporizer.
Press the start button on the vaporizer. The LPG inlet solenoid will energize while the start button is pressed. Upon releasing the start button the solenoid will de- energize if the vapor temp. Is below approx.43°c, but the unit remains on. When the vapor temp. Reaches the low vapor temp. Switch set point the solenoid will energize and vaporization will start.
Check the system for leaks. The system is now ready for operation. To begin operation, open the vaporizer
outlet valve and start the LPG pump as applicable.
Standby condition:
Perform the following procedure to place the unit in standby condition:
Close the vapor outlet valve. Leave open all LPG valves from the storage
system and pumps to liquid gas inlet to the vaporizer.
Leave open all the valves of steam supply. The vaporizer is ready to operate. All that is
needed to activate it is to open the vapor outlet valve and push the start button.
Start up procedure for Transfer pumpNote: Transfer pump is used to transfer the liquid gas from tanks to vaporizer when there is not sufficient availability of natural vapour and vaporizer has to be started.
Section in-
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Operation
manual
Q-SHE WORK INSTRUCTION WORK INSTRUCTION FOR PROPANEGAS STORAGE PLANT
ISO 9001: 2000 ISO 14001: 2004
BS OHSAS 18001:2007
7.5.1 4.4.6 4.4.6DOC NO: CR-UL/05/W PAGE: 13 OF 17REV. NO: 01EFF. DATE: 01/09/10
APPROVED BY ISSUED BY
S. No. Activity Responsibility Reference
Document
Primary Check ups
i. Ensure Inlet & outlet valves of the pump are open.ii. Ensure bypass valve of the pump is closed.
The valve on the liquid return line must be open.
As pump starts, check the direction of shaft rotation and confirm with the arrow marked on the pump.
With the pump in operation, slowly close the valve in the pump discharge line. This forces the pump output to go the tank through the liquid return line.
Subtract the pressure gauge readings of suction & discharge of the pump to obtain the system differential pressure that is determined by the adjustment on the separate bypass valve.
Adjust the bypass valve on liquid return line to obtain a system differential pressure that is at least 15 psig higher than the maximum required differential pressure. The pinned locknut, on the bypass valve adjustment screw sets the maximum Differential pressure permitted.
Close bypass valve (on liquid return line to the tank), and adjust the internal pump relief valve to a differential pressure that is 25 psig greater than the bypass valve differential.
Check the general performance of the pump- e.q. Discharge, noise level (if any), signs of overheating, Vibration and leakage etc.
Section in-
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Q-SHE WORK INSTRUCTION WORK INSTRUCTION FOR PROPANEGAS STORAGE PLANT
ISO 9001: 2000 ISO 14001: 2004 BS OHSAS 18001:2007
7.5.1 4.4.6 4.4.6
DOC NO: CR-UL/05/W PAGE: 14 OF 17REV. NO: 01EFF. DATE: 01/09/10
APPROVED BY ISSUED BY
MAINTENANCE OF INSTALLED EQUIPMENTS
1. Unloading Compressor:
Following Maintenance are done on unloading compressor as per schedule mentioned in the check list. a. Standard parameters:
Sl No. Description UoM Std. Max. tolerance1 V –Belt tension Inch 1/4- 3/82 Crankcase oil pressure (Std & Min) Psig 25 & >153 Piston clearance Inch 0.02-0.0354 Crankshaft end play Inch 0.0015- 0.0030
Note: For troubleshooting, Refer Appendix –I Page No. 21 of Operation & Maintenance manual of Propane storage & Distribution System
b. Periodic Check list of Unloading compressor
Service description DailyWeekl
yMonthl
y6
monthsYearly
Overall visual check Crankcase oil pressure Suction & Discharge pressure
Drain distance piece Drain liquid from accumulation points
Clean compressor cooling fins
Crankcase oil level* Mounting & anchor bolts V Belt tension Oil & external oil filter* Cleaning of Inlet filter/Strainer
Inspect valves Lubricate 4 Way valve Lubricate motor bearing Inspect Motor starter contact points
* Change oil every 1000 hrs of operation, or every six months whichever is earlier.
Q-SHE WORK INSTRUCTION WORK INSTRUCTION FOR PROPANEGAS STORAGE PLANT
ISO 9001: 2000
ISO 14001: 2004
BS OHSAS 18001:2007
7.5.1 4.4.6 4.4.6DOC NO: CR-UL/05/W PAGE: 15 OF 17REV. NO: 01EFF. DATE: 01/09/10
APPROVED BY ISSUED BY
2. Unloading Pump
a. Standard parameters:Sl No. Description UoM Std. Max. tolerance
1 Coupling alignment of pump InchParallel 0.005Angular 0.005
2 V –Belt tension of pump Inch/ inch of span 1/64
Note: For troubleshooting, Refer Appendix –H Page No. 11 of Operation & Maintenance manual of Propane storage & Distribution System
b. Periodic Checklist of Unloading pump:
Sl No. Description Frequency1 Cleaning of Strainer at pump inlet Monthly2 Checking of Bearings Grease * Monthly3 Checking of Belt tension Monthly
* Change grease of main & auxiliary bearings every 2 months.
3. Transfer Pump
a. Standard parameters:
Sl No. Description UoMMax. permissible limit of deviation
1 Coupling alignment InchParallel 0.005Angular 0.005
2 V –Belt tension Inch/ inch of span 1/64Note: For troubleshooting, Refer Appendix –J Page No. 11 of Operation & Maintenance manual of Propane storage & Distribution System
Q-SHE WORK INSTRUCTION
WORK INSTRUCTION FOR PROPANEGAS STORAGE PLANT
ISO 9001: 2000
ISO 14001: 2004 BS OHSAS 18001:2007
7.5.1 4.4.6 4.4.6DOC NO: CR-UL/05/W PAGE: 16 OF 17REV. NO: 01EFF. DATE: 01/09/10
APPROVED BY ISSUED BY
4. Propane Vaporizer
a. For General Maintenance of the components of vaporizer refer Appendix –K Page No. 16, 17 & 18 of Operation & Maintenance manual of Propane storage & Distribution System
b. Maintenance ScheduleDescription Monthly As reqd. Six months Yearly Two yearlySolenoid valve checkTemperature Transmitter
Recalibrate
Condensate Strainer check cleanLPG Inlet Strainer check cleanCondenser Tube Clean as
reqd.Steam strainers check cleanBolt Connectors Tighten
Note: For troubleshooting, Refer Appendix –K Page No. 20 of Operation & Maintenance manual of Propane storage & Distribution System
Safety Precautions
Filling operation is to be carried out between sunrise & sunset only. Strainer on the liquid line must be cleaned once in a month. The tank must never be overfilled, as it may result in to very serious
accident. Do not ever run the pump and the compressor when their outlet valves
are closed. Only trained personnel should be employed for carrying out unloading
operation. As the properties of Propane differ in a no. of aspects from those of many
general products, all people concerned with handling Propane must be instructed in safe procedure before taking up their duties.
Source of ignition must never be taken near any Propane/ LPG liquid or vapor.
Smoking in the battery limit should be strictly forbidden. Only flame proof lamps & torches of approved make should be used with
in the battery limit.
Incendiary sparks can be produced when tools strike concrete & stone , whether the tool are ferrous or non ferrous .To avoid it always use non sparking tools for.
Q-SHE WORK INSTRUCTION WORK INSTRUCTION FOR PROPANEGAS STORAGE PLANT
ISO 9001: 2000
ISO 14001: 2004
BS OHSAS 18001:2007
7.5.1 4.4.6 4.4.6DOC NO: CR-UL/05/W PAGE: 17 OF 17REV. NO: 01EFF. DATE: 01/09/10
APPROVED BY ISSUED BY
6. Reference Document/Record
a).Checklist (Common for Both Old & New Propane Storage Plants) : Refer Annexure for format
Sl no Description Format no. 1. Preventive checklist for LPG/ Propane JSL/CRD/SAFETY/O4, Rev.011. Checklist For LPG/Propane unloading CR-UL/05-A/CL
b). Log Books (Refer Annexure for format)Sl no Description Format no. Old LPG/Propane storage plant1. Log sheet For Propane unloading CR-UL/05-D/CL2 Log sheet for Equipment Handling CR-UL/05-B/LBNew LPG/Propane storage plant3 Log sheet For Propane unloading CR-UL/05-D/CL/NEW4 Log sheet for Equipment Handling CR-UL/05-B/LB/NEW
c). Operation & Maintenance Manual.
7. Retention & Distribution:
Retention:ISO department for a period of two years from the date of super cession thereof shall preserve the master copy of this document or of individual pages.
Distribution:
Sr. No.
Custody Location Remarks
1
2
3
Gas Plant
Gas plant Operation in-charge
Maintenance Shift in-charge
Gas Plant
Shift Cabin
Master Copy
Controlled Copy
Controlled Copy