2014-4800-1H-0003

SU TU TRANG FULL FIELD DEVELOPMENT – PHASE 1

DETAILED ENGINEERING AND PROCUREMENT ENGINEERING SUPPORT SERVICES

VALVING & ISOLATION PHILOSOPHY Doc. No.: 2014-4800-1H-0003

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REVISION RECORD SHEET

No. Rev. No. Content of Revision Date of

Revision

2 B Approved for Design (FEED) 27-11-14

3 C Issued for Review

Updating and developing from FEED stage 15-05-15

4 D Issued for Approval 29-06-15

5 E Approved for Design 30-07-15




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TABLE OF CONTENTS

1.0 INTRODUCTION 5

1.1 DESCRIPTION OF FACILITIES 5

1.2 DOCUMENT PURPOSE 5

1.3 ABBREVIATION AND DEFINITION 6

2.0 GENERAL OBJECTIVES 6

3.0 DEFINITIONS 7

3.1 SEVERE SERVICE 7

3.2 NON-SEVERE SERVICE 7

3.3 CRITICAL SERVICE 7

3.4 NON-CRITICAL SERVICE 7

3.5 POSITION ISOLATION 7

3.6 GENERAL ISOLATION 7

3.7 HIGH PRESSURE 7

3.8 LOW PRESSURE 7

3.9 DOUBLE BLOCK AND BLEED 8

3.10 DOUBLE BLOCK WITHOUT BLEED 8

3.11 SINGLE BLOCK AND BLEED 8

3.12 SINGLE BLOCK 8

3.13 INTERLOCKED OPEN / CLOSED 8

3.14 LOCKED OPEN / CLOSED 9

3.15 CAR SEAL OPEN / CLOSED 9

3.16 SHUTDOWN VALVE (SDV) 9

3.17 LIVE FACILITY 9

3.18 CONFINED SPACE 9

3.19 TRAIN 9

3.20 BLOWNDOWN VALVE 9

3.21 SOUR SERVICE 9

3.22 SWEET SERVICE 9

3.23 ABBREVIATION 10

4.0 SYSTEM ISOLATION AND VALVING REQUIREMENTS 10

4.1 GENERAL GUIDELINES 10

4.2 MAINTENANCE ISOLATION 15




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4.3 CONFINE SPACE ENTRY 15

4.4 EQUIPMENT 15

4.5 VALVES 16

4.6 PACKAGE EQUIPMENT 17

4.7 INSTRUMENT ISOLATION 18

4.8 DRAIN AND VENT 18

4.9 POWERED EQUIPMENT ISOLATION 19




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1.0 INTRODUCTION

1.1 DESCRIPTION OF FACILITIES

The Su Tu Trang (White Lion) field is located at the South end of Block 15-1 (approximately 20km’s South of STV) in approximately 56 meters of water. The Block 15-1 contract area is located in the Cuu Long Basin offshore southern Vietnam, 180 kilometres southeast of Ho Chi Minh City. The development of Su Tu Trang started in September 2012 with the Long term Production Testing Phase (LTPTP). It consists of a remote, unmanned wellhead platform (WHP-C) that produces to and is controlled from the Su Tu Vang CPP. The platform has the capability of handling up to 4 high pressure gas wells. Present production is 6,000 BPD of condensate and 50 MMSCFD of gas and all the STT produced fluids are exported for processing to the Su Tu Vang CPP via a multiphase 12” pipeline.

Production of the Su Tu Trang Field is now bottlenecked by the CPP process capacities, and most significantly by the gas export pipeline to shore and the gas sales demand in South Vietnam.

The purpose of the Phase 1 of Su Tu Trang Full Field Development is to face these restrictions by allowing the increase of the condensate production while keeping the gas export flow rate steady. It will also provide more reservoir information to support STT Full Field Development Phase 2 that will significantly increase gas production/export.

The Project consists of the installation of a reinjection platform (ST-PIP) bridge-linked to the existing WHP-C, the drilling of two new wells on ST-PIP and the conversion from producers into injectors of two existing wells on WHP-C. The outcome of the project will be a continuous production rate of 150 MMSCFD, a reinjection rate of 100 MMSCFD, an export rate of 50 MMSCFD to Bach Ho via CPP (no change), and an incremental condensate production of 13,000 BPD.

ST-PIP will be bridge-linked to a separated living quarters platform designed for 20 pax during Phase 1, but extendable to 60 pax at a later stage. In addition to accommodation, ST-LQ will be equipped with most of the utilities for ST-PIP. It is also designed to be bridge-linked to a separated Central Gas Facility Platform (CGF) in the future (Phase 2).

1.2 DOCUMENT PURPOSE

This philosophy describes the provisions to be made for isolation of process equipment or sections of plant to permit safe operation and to provide access for maintenance and inspection while allowing continued safe operation where required. A basis for valve arrangements around control valves, relief valves, shutdown valves, blowdown valves, etc. is included.

Isolation is to be accomplished by the use of block valves and / or the insertion of spectacle blinds or spades, or the removal of spool pieces and the installation of blind flanges. The location of the isolation to enable maintenance and inspection is dependent upon the extent of shutdown, hazardous nature of the contained fluids, and the pressure rating of the piping system in question.

It is recognized that there may be individual instances where for safety reasons or significant engineering technicalities the philosophy detailed in this document cannot be achieved. In these




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cases a review will be carried out jointly by the relevant engineering group and Operations to establish a safe and justifiable alternative. Selection of valves or other isolation devices to accommodate any deviations from this basis of design shall only be made from types currently in similar service with a known performance and maintenance history.

Fully auditable documentation supporting any agreed changes shall be available and retained for future reference as part of the project files.

1.3 ABBREVIATION AND DEFINITION

1.3.1 Definition

Definitions used in this document are described below:

COMPANY

[CPY]

CUU LONG JOINT OPERATING COMPANY. [CLJOC]

EPCI CONTRACTOR

[CTR]

PTSC MECHANICAL & CONSTRUCTION CO., LTD.

[PTSC M&C]

DETAILED ENGINEERING INTEGRATED TEAM

[DE]

TECHNIP VIETNAM CO., LTD. [TPVN]

PTSC MECHANICAL & CONSTRUCTION CO., LTD. [PTSC M&C]

PETROVIETNAM ENGINEERING COMPANY. [PVE]

VENDOR Party responsible for manufacturing and/or packaging of equipment.

SUB-VENDOR Other entity employed by VENDOR to perform work and/or supply equipment.

1.3.2 Abbreviation

ST-PIP : Reinjection platform ST-LQ : Living quarter platform STT : Su Tu Trang

2.0 GENERAL OBJECTIVES

The methods of isolation required and precautions taken will be defined by the frequency and

level of risk that the work to be done on a system will involve. Where hazards are identified as

capable of causing injury to personnel or damage to plant, total and secure isolation from the risk

shall be achieved.This document describes the valving and isolation philosophy to be adapted for

the design of Su Tu Trang Complex. The objectives of this philosophy are:

To define safe isolation methods, draining, purging and venting provision for on-line plant

containing process (oil, gas, condensate, produce water and hazardous chemical), utility

liquid and gases, hence operation, maintenance and inspection can take place with minimum

plant shut down.




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To ensure necessary facilities are incorporated in the design.

To minimize cost impact whilst maintaining safety objectives.

3.0 DEFINITIONS

3.1 SEVERE SERVICE

All systems containing produced hydrocarbons

All systems containing hydrogen sulfide gas and Mercury

All systems at ASME 900# flange rating or above

Heating Medium

Hazardous liquids used above atmospheric pressure or with a flash point below 60ºC

(140ºF)

3.2 NON-SEVERE SERVICE

All systems not classified as severe service.

3.3 CRITICAL SERVICE

A process system (normally gas/liquid production), considered critical to maintain facility

production rates.

3.4 NON-CRITICAL SERVICE

All systems not classified as critical service.

3.5 POSITION ISOLATION

A physical barrier, where no leakage can be tolerated for safety or contamination reasons.

Positive isolation is provided by spectacle blinds, spades or removable spools that allow for the

installation of blind flanges.

3.6 GENERAL ISOLATION

Isolation for a specific work activity where the requirements are less critical than needed to

ensure Positive Isolation. Typically in non-hazardous and low pressure hazardous services.

3.7 HIGH PRESSURE

Service where the system pressure class rating is ANSI Class 300 or above.

3.8 LOW PRESSURE

Service where the system pressure class rating is ANSI Class 150 or below.




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3.9 DOUBLE BLOCK AND BLEED

An isolation system providing two seals against fluid flow and incorporating an intermediate

venting facility to monitor performance of the first seal and prevent pressure build up on the

second seal.

Double Block and Bleed can be provided by one of the following methods:

By two separate block valves with a vent valve on the interconnecting pipework.

By modular or mono-flange double block and bleed valve assemblies.

By valve types which by nature provide two mechanically activated seats with a cavity bleed

(such as expanding slab, through conduit gate valve with body cavity vent). Such valves

require the provision of a body cavity relief valve which should be incorporated into the vent

assembly. Such valves also have a preferred orientation with regard to sealing direction if

the need to equalize across the valve to open it is to be avoided.

By special ball valves with dual seats and a body cavity vent.

Notes:

Use of a Shutdown Valve (fail closed) as the second valve in a DBB configuration is

acceptable provided that the SDV controls are deactivated.

Use of widely separated process block valves is acceptable provided the trapped volume

between the two block valves is less than 1.5m3.

3.10 DOUBLE BLOCK WITHOUT BLEED

An isolating system providing two seals against fluid flow using two independent valves. This is

generally used for vents and drains, etc. but exceptionally also used with a downstream vent to

provide for installation of positive isolation for equipment maintenance.

3.11 SINGLE BLOCK AND BLEED

A single valve with a bleed valve located on the downstream side so that leakage can be tested

prior to breaking a flange.

3.12 SINGLE BLOCK

Single valves are used to provide system isolation in non-severe service and to divert flows in

operating systems.

3.13 INTERLOCKED OPEN / CLOSED

An interlocking system where valves are always secured in the open or closed position to provide

safe operating conditions. Proper valve sequencing must be ensured by an interlocking system.




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3.14 LOCKED OPEN / CLOSED

A system where valves shall be secured in the Open or Closed position by keyed locks to provide

safe operational isolation.

3.15 CAR SEAL OPEN / CLOSED

A system where valves shall be always secured in the Open or Close position by car seals to

provide temporary operational isolation.

3.16 SHUTDOWN VALVE (SDV)

A block valve that is actuated through the SIS System. This valve is tested regularly and is not

used for any form of process control. The valve is fail closed.

3.17 LIVE FACILITY

Anytime the facility is processing produced fluids the facility is considered “live”. The facility is

considered “dead” only when the facility is isolated from producing pipelines or wells and the

facility has been completely blown down and drained of hydrocarbon liquids.

3.18 CONFINED SPACE

An area or vessel that normally contains a fluid or gas under pressure and that may have a limited

entry or exit provision (e.g. manway) and that may require entry for inspection or periodic

service.

3.19 TRAIN

A train is defined as comprising one or more pieces of equipment which are similar in function

and capacity and operate in parallel with another similar grouping, such that each grouping can

operate independently of one another (e.g. Lift Gas Compression)

3.20 BLOWNDOWN VALVE

A block valve that is actuated through the ESD System. This system is tested regularly as per

applicable safety regulation. It is not use for process control.

3.21 SOUR SERVICE

All severe service system containing more than 10 ppm Hydrogen Sulphide (H2S).

3.22 SWEET SERVICE

All severe service systems containing less than 10 ppm Hydrogen Sulphide (H2S).




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3.23 ABBREVIATION

DB Double Block

DBB Double Block and Bleed

IDBB Integral Double Block and Bleed

SBB Single Block and Bleed

SB Single Block

ILO Interlocked Open

ILC Interlocked Closed

LO Locked Open

LC Locked Closed

CSO Car Seal Open

CSC Car Seal Closed

NO Normally Open

NC Normally Closed

SDV Shutdown Valve

BDV Blowdown Valve

PSV Pressure Safety Valve (Relief Valve)

RO Restriction Orifice

FB Full Bore

RB Reduced Bore

VOC Volatile Organic Compound

4.0 SYSTEM ISOLATION AND VALVING REQUIREMENTS

4.1 GENERAL GUIDELINES

Isolation of sections of plant or equipment will be generally divided into two types:

4.1.1 Positive Isolation

Where an absolute guarantee of segregation (i.e. no leakage) is required between the isolated

section and the surrounding plant. Positive isolation is typically provided by non-valve methods,

such as spectacle blinds, spades, or removable spools that allow for installation of blind flange.




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The following table 4.1 provides general guideline on the application for positive isolation.

TABLE 4.1 : POSITIVE ISOLATION METHOD

Isolation Type / Application

Method

Positive Isolation

Used where no leakage can be tolerated, e.g.;

All confined space entries

To prevent cross contamination of

utilities with process

To isolate a process train from other

hazardous process / utilities for the

purpose of overhaul / inspection

Hot Work

For process fluids above ignition

temperature

Positive Isolation can be achieved by any of

the following:

Removable Spool & Blind Flange

Spade and Spacer

Spectacle Blind

The use of process isolation valves is NOT

acceptable for positive isolation.

Table 4.2 and 4.3 provide the general limits of use for blinds, spacers and removable spools for

the different piping sizes and classifications.

TABLE 4.2 : LIMITS OF USE OF BLINDS, SPACERS AND SPOOLS – CARBON STEEL PIPING

Line Size (Inch NB)

150# (RF)

300# (RF)

600# (RF)

900# (RTJ)

1500# (RTJ)

2500# (RTJ)

API 10000#(RTJ)

¾”

SPECTACLE BLIND

1” 1½” 2” 3” 4” 6” 8” 10”

REMOVABLE SPOOL

& BLIND FLANGE

12”

14” SPACER & SPADE

Over 14”




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TABLE 4.3 : LIMITS OF USE OF BLINDS, SPACERS AND SPOOLS – NON-CARBON STEEL PIPING

Line Size (Inch NB)

150# (RF)

300# (RF)

600# (RF)

900# (RTJ)

API 10000# (RTJ)

¾” 1”

1½” 2”

SPECTACLE BLIND

3” 4” 6” 8” 10” 12” REMOVABLE SPOOL 14” SPACER & SPADE & BLIND FLANGE

Over 14”

In general the above selections are based upon use of a spade and spacer when the weight of a

spectacle blind exceeds 50 kg.

The following options exist for achieving Positive Isolation:

1) Spade Only

Spreading the flange and inserting a spade blind – limited to small bore piping only.

2) Spectacle Blind

Combined spacer and blind system used where weight is less than 50 kg.

3) Spacer and Spade Blind

Installation of a spacer of the same thickness as the fully rated spade blind. The spacer facilitates

the installation of the spade blind when required (via use of jacking screw)

4) Removable Spools and Blind Flange

These are normally used when:

Piping is too large to enable a flange to be sprung and a spade installed, but when a

permanent spacer is not justified

Insufficient flexibility exists to enable the use of a spectacle blind / spacer and spade.




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Vessel/Equipment relief system isolation

In general:

The final installation must be operable and maintainable

Jacking loads must be within the practical limits of what can be applied at site

Removable spools must be able to be swung or lifted out; i.e. adequate space and material

handling provisions supplied

Pre-investment in installed spectacle blinds or spacers must be justified based on frequency

of use and non-practicality of other means of isolation

The number of gaskets and potential leak points is to be minimized.

4.1.2 Valve Isolation

Where the isolation of the section is performed by one or more valve but the guarantee of

segregation is not required.

The following table 4.4 provides general guideline on the application for valve isolation.

TABLE 4.4 : VALVE ISOLATION METHOD

Isolation Type / Application Method

High Integrity Isolation (Double Block and Bleed)

To be used:

Where vessels and equipment rated at ANSI Class 600 and

above are to be isolated from live process and it is

anticipated that isolation will be required for an extended

period (i.e. longer than one shift) then Type 1 shall be

employed.

Where equipment and piping rated to ANSI Class 300 and

below are to be isolated from live process for extended

periods of maintenance then Type 2 may be used.

Where equipment is to be isolated from a large inventory

(e.g. pipeline) Type 1 to be employed.

For control valves or PSVs in ANSI Class 600 service or

above where the exposure time is limited (within one

shift). For control valves without a bypass, and a spec

break downstream to ANSI Class 300 or less, then a single

Achieved by:

Type 1

Double Block and Bleed

– Two separate valves

and bleed

Double Block and Bleed

– Two valves in one

body and bleed

Type 2

Integral Double Block and Bleed

valve (limited to ANSI Class

300 service)




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isolation valve on the downstream side is acceptable.

General Isolation

To be used when:

A level of segregation is required for non-hazardous

services or for low pressure, infrequent hazardous service

Isolation is required for individual items of equipment in

hazardous service within a system already isolated by DBB

as per Type 1. Note – This is to allow maintenance of

individual items without the need for full drainage and

purging; only system depressurization is required.

General Isolation can be

achieved by either of the

following:

Single block valve (SB)

Single Block and Bleed

(SBB)

Non return valves and control

valves may NOT be used for this

duty.

System Isolation

Used to isolate one hydrocarbon system from another.

System isolation can be

achieved by DBB for all systems

ANSI Class 300 and above and

class 150 with typically

flammable, corrosive or toxic

service.

TABLE 4.5 : RECOMMENDED APPLICATION FOR GENERAL AND HIGH

INTEGRITY ISOLATIONS

Fluid / Nature Low Pressure

ANSI Class 150

High Pressure

ANSI Class 300 or higher

Process Fluids – Typically

flammable, corrosive or toxic.

DBB DBB

Utilities. Typically non-flammable,

non-corrosive and non-toxic.

SBB DBB

Process Fluids – Services requiring

frequent operator intervention (i.e.

pigging)

DBB DBB




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4.2 MAINTENANCE ISOLATION

4.2.1 Process Train Isolation

Dedicated isolation valves need not be provided for unspared equipment within a train except:

Where the equipment can be bypassed and the process allowed continuing in operation

To reduce system size to a reasonable value with respect to inventory vented (loss of

product and / or environmental considerations) and with respect to gas freeing and purging

requirements.

Equipment spared within the train must be provided with isolation at the inlet and outlet in

accordance with Table 4.1.

4.2.2 Flow line Isolation

Production flow lines shall be provided with DBB to allow isolation of individual flow lines and

wells. This is to allow access to choke valves or tie-ins of additional lines without the

requirement for shutting down and depressurizing the main manifold.

4.3 CONFINE SPACE ENTRY

An area or equipment normally containing a fluid that may have limited entry and exit provision

to allow entry for inspection and periodic service shall be provided with isolation as described

below:

Valve isolation as per Table 4.4

Positive isolation as per Table 4.1

Drain isolation as per section 4.8

PSV isolation as per section 4.5.2.

If entry is required to a vessel, a pump or compressor is dismantled, while the facilities is

live, the isolation valve should be provided to enable the blinds to be installed or spool pieces

removed.

4.4 EQUIPMENT

Equipment that is not within a train but which is spared and sufficiently critical to operations for

maintenance of services of this equipment while the facilities is live may be required, shall have

provision for positive isolation. (Including DBB if required by the service).

Equipment not intent to be disconnected of taken out of services while the facility is live does not

require isolation. However, isolation may still be provided to facilitate operation and

maintenance, and to minimize purging volumes and duration and reduce maintenance intervals.




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4.5 VALVES

4.5.1 Control Valves

Control valves shall be provided with inlet and outlet isolation valves. Requirements for single

block or double block are to be determined based on the guidelines provided in Table 4.4 and

Table 4.5 in conjunction with evaluation of service criticality.

Critical service is defined as that where facility production would stop if the valve failed or were

taken out of service. This also applies to control valves where two separate, parallel valves have

been provided to ensure availability. The spare valve or the one not specifically in service must

have provisions for adequate isolation for maintenance purposes.

Isolation valves shall be full line size and reducers, if required to match control valve size, shall

be located inside the block valves. Reducer spool pieces should be large enough to handle

increasing to the next larger control valve body size without modifications to the control valve

station isolation valves.

Control valve manifolds shall be provided with drain valves to allow venting / draining after

isolation, the number of valves shall be decided on a case by case basis depending on the failure

position and location of the control valves.

Check valves provided for prevention of backflow shall be provided downstream of the control

valve manifold and bypass connection to allow for maintenance and inspection. Bypass operation

is to be controlled by procedure and continuously attended.

Where a control valve capacity sets a downstream relief valve sizing basis, then the control valve

bypass valve, if provided, shall be Car Seal Closed and its operation controlled by procedure.

4.5.2 Relief Valves (PSVs)

Where relief valves are spared, the inlet isolation shall be provided such that the spares are

Interlocked together. This is to ensure controlled changeover and following of the correct

sequencing and can be achieved by either special inlet valve manifolds which automatically place

one valve in service when the other is isolated or by locking (and reliance upon procedure)

individual inlet block valves into position.

All relief valves discharging into a closed system shall be fully isolatable with each PSV having a

dedicated outlet isolation valve. Outlet block valves, including those for spare service, shall be

locked open.

All relief valves of size greater than 1.5” x 2” shall be equipped with inlet and outlet bleed rings

to allow testing in place. Relief valves of size 1.5” x 2” and smaller shall be equipped with bleed

valves within the isolation valves to allow testing in place.




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Testing in place provisions for relief valves located within packaged, but isolatable equipment

trains, will necessitate the installation of PSV inlet isolation valves and bleeds as noted above.

4.5.3 Shutdown Valves

High integrity valves will be used in key areas for shutdown valves. These valves will isolate

various portion of the process. Unless special circumstances exist, no isolation valves are

required for individual SDVs as the process system in question will be depressured prior to

maintenance of an SDV.

SDVs on vessel liquid outlets should be located as near to the vessel outlet flange as practical.

The need for pressurization bypasses shall be determined by the start up procedure and

philosophy. The size of a bypass shall be based upon the volume of the system to be pressurized

and the initial pressure differential across the valve. All SDVs with start-up bypass shall have a

differential pressure permissive to prevent the SDV from opening under high differential

pressure. All transmitter tapping points used for differential pressure permissives shall be local

to the valve (within 3 meters).

Manual pressurization valves should be Locked Closed when not in use. These valves should be

globe valves capable of throttling across large pressure differentials.

4.5.4 Blowdown Valves

All blowdown valves shall have upstream and downstream isolation valves so that they may be

isolated from both the process and the relief system. These valves shall be Locked Open.

Where needed, a Restriction Orifice (RO) may be provided on the downstream side of the BDV.

The RO shall be sized such that in high pressure systems the pressure drop occurs across the

orifice rather than the BDV itself.

RO’s shall be located within the BDV station isolation valves.

Inlet BDV isolation valves may be reduced port. Isolation valves downstream of the BDV and

RO assembly shall be full port.

4.6 PACKAGE EQUIPMENT

Package equipment connected to the process and utility systems will be provided with flange,

isolation valves and if necessary, blinding facilities at the skid limits.

Yard valves provided within the compression package shall only be used for isolation of the

associated package equipment and controlled / actuated from its local control panel. These yard

valves shall not be used the main SDV for process system isolation (i.e. not connected to the PSD

system).




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4.7 INSTRUMENT ISOLATION

4.7.1 Level Instrumentation

For 150#

Level instrumentation on all vessels shall be provided with single ball valve assembly as the

process isolation.

For 300# and above

Level instrumentation on all vessels shall be provided with integral double block and bleed

assembly as the process isolation.

4.7.2 Pressure Instrumentation

For 150#

Pressure instrumentation shall be provided with an integral single block and bleed, single ball

valve for piping class ‘A8’ assembly as the process isolation.

For 300# and above

Pressure instrumentation shall be provided with an integral double block and bleed assembly as

the process isolation.

4.7.3 Small Bore Pipework

Small bore pipework (e.g. level bridles) of size 40 mm and below can be isolated using general

isolation (SB) except for high pressure systems class 600 or more where DBB shall be used. This

can be reviewed on a case by case basis based on normal operating conditions.

4.8 DRAIN AND VENT

4.8.1 Vessel Vents

Manual maintenance vent connections, routed to the flare, shall be provided as required and as

indicated by the P&IDs. The vent connections shall comprise a globe valve (process side)

followed by an isolation valve.

Minimum size for vent connections to closed relief systems is 2”.

4.8.2 Vessel Drains

Vessel Drainage in Hazardous Areas

Vessels in hydrocarbon service shall be provided with a drain connection to the Closed Drain

Header. The drain connection may be either directly off the vessel or on the liquid outlet piping

assuming that it is at a low point and adequate natural drainage is provided.

Closed Drain System connections shall consist of a globe valve (process side) followed by an

isolation valve. A Restriction Orifice may be provided to limit gas blow by throughput.




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Ball valve only connections to the Closed Drain System may be considered for low pressure,

non-flashing service subject to COMPANY approval.

Vessel Drainage in Non-Hazardous Areas

Vessels in non-hazardous areas will be provided with a single drain valve. The drained fluids

will be routed to the Non-Hazardous Open Drain System via tundish or deck drain.

4.9 POWERED EQUIPMENT ISOLATION

Powered equipment isolations can be segregated by driver type. Specifically:

Electrically Driven

Pneumatically Driven or Hydraulically Driven

Engine or Turbine Driven

4.9.1 Electric Drives

Electrically power equipment shall be capable of being properly isolated under the Cuulong

Electrical Isolation Procedures and Permit to Work System.

4.9.2 Pneumatic or Hydraulic Drives

Hydraulic or pneumatic powered equipment shall be capable of being isolated by lockable

isolation valves and breaking of the motive source and return lines. Any reservoirs in the supply

side shall have lockable vents and / or drains.

4.9.3 Engine or Turbine Drives

Engine or turbine driven equipment shall be isolated by locking off the fuel supply to the engine

and the isolation of all starting systems. If the driver is part of a package then the package shall

include a master lockable isolation device to prevent any start up sequence from being initiated.

Documents

2014-4800-1H-0003