SIST EN ISO 13354:2014

Petroleum and natural gas industries - Drilling and production equipment - Shallow gas diverter equipment (ISO 13354:2014)

EN ISO 13354 specifies requirements for the selection of the diverter equipment for rigs used to drill shallow-gas-bearing formations. It covers both onshore and offshore drilling operations, and considers also the auxiliary equipment associated with floating rigs. The specified requirements concern the following diverter equipment: - annular sealing devices; - vent outlets; - diverter valves; - diverter piping. This International Standard highlights the concerns associated with the selection of a marine floating drilling support. It covers safety issues concerning key rig equipment, and important steps of action required prior to starting the drilling operations.This International Standard highlights the concerns associated with the selection of a marine floating drilling support. It covers safety issues concerning key rig equipment, and important steps of action required prior to starting the drilling operations. It provides only general guidelines regarding the response to be given to a shallow-gas flow.

Erdöl- und Erdgasindustrie - Shallow gas Diverterausrüstung (ISO 13354:2014)

Industries du pétrole et du gaz naturel - Équipements de forage et de production - Équipement déflecteur pour gaz de surface (ISO 13354:2014)

L'ISO 13354:2014 spécifie les exigences pour le choix de l'équipement déflecteur des appareils de forage qui sont requis pour forer des formations contenant du gaz de surface. Elle couvre les opérations terrestres et en mer, ainsi que les équipements auxiliaires requis sur les engins flottants.
Les exigences spécifiées concernent les équipements suivants:
? dispositif d'obturation annulaire;
? sorties d'évent;
? vannes du système déflecteur;
? conduites du système déflecteur.
L'ISO 13354:2014 met en lumière les préoccupations associées à la sélection d'un support de forage flottant. Elle couvre les aspects sécurité liés à des équipements essentiels de l'appareil de forage, ainsi que les actions importantes devant être réalisées avant le démarrage des activités de forage.
Elle ne fournit que des recommandations d'ordre général à propos des actions à mener en cas de venue de gaz de surface.

Industrija za predelavo nafte in zemeljskega plina - Vrtalna in proizvodna oprema - Oprema "Shallow gas diverter" (ISO 13354:2014)

Standard EN ISO 13354 določa zahteve za izbor opreme za preusmeritev za ploščadi, ki se uporabljajo za vrtanje plitvih formacij plinov. Zajema postopke kopenskega vrtanja in vrtanja v morsko dno ter dodatno opremo, povezano s plavajočimi ploščadmi. Določene zahteve se nanašajo na naslednjo opremo za preusmerjanje: obročaste tesnilne naprave; - prezračevalne odprtine; - preklopne ventile; - preklopne cevovode. Ta mednarodni standard izpostavlja težave, povezane z izbiro morske plavajoče podpore za vrtanje. Zajema vprašanja o varnosti v zvezi s ključno opremo za ploščadi in pomembne korake za ukrepanje, ki so potrebni pred začetkom vrtanja. Ta mednarodni standard izpostavlja težave, povezane z izbiro morske plavajoče podpore za vrtanje. Zajema vprašanja o varnosti v zvezi s ključno opremo ploščadi in pomembne korake za ukrepanje, ki so potrebni pred začetkom vrtanja. Zagotavlja le splošne smernice glede odzivov na tok plitvih formacij plina.

General Information

• Status: Published
• Public Enquiry End Date: 19-Jan-2014
• Publication Date: 28-Sep-2014
• ICS: 75.180.10 - Exploratory, drilling and extraction equipment
• Technical Committee: I13 - Imaginarni 13
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 24-Sep-2014
• Due Date: 29-Nov-2014
• Completion Date: 29-Sep-2014
• Ref Project: EN ISO 13354:2014 - Petroleum and natural gas industries - Drilling and production equipment - Shallow gas diverter equipment (ISO 13354:2014)

Standards Content (sample)

SLOVENSKI STANDARD
SIST EN ISO 13354:2014
01-november-2014

Industrija za predelavo nafte in zemeljskega plina - Vrtalna in proizvodna oprema -

Oprema "Shallow gas diverter" (ISO 13354:2014)

Petroleum and natural gas industries - Drilling and production equipment - Shallow gas

diverter equipment (ISO 13354:2014)
Erdöl- und Erdgasindustrie - Shallow gas Diverterausrüstung (ISO 13354:2014)

Industries du pétrole et du gaz naturel - Équipements de forage et de production -

Équipement déflecteur pour gaz de surface (ISO 13354:2014)
Ta slovenski standard je istoveten z: EN ISO 13354:2014
ICS:
75.180.10 Oprema za raziskovanje in Exploratory and extraction
odkopavanje equipment
SIST EN ISO 13354:2014 en

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN ISO 13354:2014
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SIST EN ISO 13354:2014
EUROPEAN STANDARD
EN ISO 13354
NORME EUROPÉENNE
EUROPÄISCHE NORM
May 2014
ICS 75.180.10
English Version
Petroleum and natural gas industries - Drilling and production
equipment - Shallow gas diverter equipment (ISO 13354:2014)

Industries du pétrole et du gaz naturel - Équipements de Erdöl- und Erdgasindustrie - Shallow gas

forage et de production - Équipement déflecteur pour gaz Diverterausrüstung (ISO 13354:2014)

de surface (ISO 13354:2014)
This European Standard was approved by CEN on 28 February 2014.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European

Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national

standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN member.

This European Standard exists in three official versions (English, French, German). A version in any other language made by translation

under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management Centre has the same

status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,

Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,

Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United

Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels

© 2014 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 13354:2014 E

worldwide for CEN national Members.
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SIST EN ISO 13354:2014
EN ISO 13354:2014 (E)
Contents Page

Foreword ..............................................................................................................................................................3

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SIST EN ISO 13354:2014
EN ISO 13354:2014 (E)
Foreword

This document (EN ISO 13354:2014) has been prepared by Technical Committee ISO/TC 67 "Materials,

equipment and offshore structures for petroleum, petrochemical and natural gas industries" in collaboration

with Technical Committee CEN/TC 12 “Materials, equipment and offshore structures for petroleum,

petrochemical and natural gas industries” the secretariat of which is held by AFNOR.

This European Standard shall be given the status of a national standard, either by publication of an identical

text or by endorsement, at the latest by November 2014, and conflicting national standards shall be withdrawn

at the latest by November 2014.

Attention is drawn to the possibility that some of the elements of this document may be the subject of patent

rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent rights.

According to the CEN-CENELEC Internal Regulations, the national standards organizations of the following

countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech

Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece,

Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,

Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom.

Endorsement notice

The text of ISO 13354:2014 has been approved by CEN as EN ISO 13354:2014 without any modification.

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SIST EN ISO 13354:2014
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SIST EN ISO 13354:2014
INTERNATIONAL ISO
STANDARD 13354
First edition
2014-05-15
Petroleum and natural gas
industries — Drilling and production
equipment — Shallow gas diverter
equipment
Industries du pétrole et du gaz naturel — Équipements de forage et
de production — Équipement déflecteur pour gaz de surface
Reference number
ISO 13354:2014(E)
ISO 2014
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SIST EN ISO 13354:2014
ISO 13354:2014(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2014

All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form

or by any means, electronic or mechanical, including photocopying, or posting on the internet or an intranet, without prior

written permission. Permission can be requested from either ISO at the address below or ISO’s member body in the country of

the requester.
ISO copyright office
Case postale 56 • CH-1211 Geneva 20
Tel. + 41 22 749 01 11
Fax + 41 22 749 09 47
E-mail [e-mail]
Web www.iso.org
Published in Switzerland
ii © ISO 2014 – All rights reserved
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SIST EN ISO 13354:2014
ISO 13354:2014(E)
Contents Page

Foreword ........................................................................................................................................................................................................................................iv

Introduction ..................................................................................................................................................................................................................................v

1 Scope ................................................................................................................................................................................................................................. 1

2 Normative references ...................................................................................................................................................................................... 1

3 Terms and definitions ..................................................................................................................................................................................... 1

4 Diverter system equipment ....................................................................................................................................................................... 7

4.1 General purpose ..................................................................................................................................................................................... 7

4.2 Findings of blowout reports ........................................................................................................................................................ 7

4.3 Applications of diverter systems ............................................................................................................................................. 8

4.4 Layout considerations — Land rigs and bottom-supported marine structures ............................ 8

4.5 Layout considerations — Floating rigs ...........................................................................................................................18

5 Floating rigs — Specific aspects .........................................................................................................................................................26

5.1 Use of the marine riser ..................................................................................................................................................................26

5.2 Additional functions of the diverter system ...............................................................................................................28

5.3 Comparison of types of floating support .......................................................................................................................28

6 Preparation for shallow gas operations ....................................................................................................................................31

6.1 Call for tender .......................................................................................................................................................................................31

6.2 Important issues .................................................................................................................................................................................31

6.3 Pre-spud checks ..................................................................................................................................................................................32

6.4 Pre-spud meetings ............................................................................................................................................................................34

6.5 Pre-spud drills ......................................................................................................................................................................................35

6.6 Preparing the response to a shallow-gas flow ..........................................................................................................36

7 Diverter system inspection and maintenance ....................................................................................................................39

7.1 General ........................................................................................................................................................................................................39

7.2 Maintenance ...........................................................................................................................................................................................39

7.3 Inspection and testing ...................................................................................................................................................................39

7.4 Diverter system piping ..................................................................................................................................................................39

7.5 Manufacturer documentation .................................................................................................................................................40

Bibliography .............................................................................................................................................................................................................................41

© ISO 2014 – All rights reserved iii
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SIST EN ISO 13354:2014
ISO 13354:2014(E)
Foreword

ISO (the International Organization for Standardization) is a worldwide federation of national standards

bodies (ISO member bodies). The work of preparing International Standards is normally carried out

through ISO technical committees. Each member body interested in a subject for which a technical

committee has been established has the right to be represented on that committee. International

organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.

ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of

electrotechnical standardization.

The procedures used to develop this document and those intended for its further maintenance are

described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the

different types of ISO documents should be noted. This document was drafted in accordance with the

editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).

Attention is drawn to the possibility that some of the elements of this document may be the subject of

patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of any

patent rights identified during the development of the document will be in the Introduction and/or on

the ISO list of patent declarations received (see www.iso.org/patents).

Any trade name used in this document is information given for the convenience of users and does not

constitute an endorsement.

For an explanation on the meaning of ISO specific terms and expressions related to conformity

assessment, as well as information about ISO’s adherence to the WTO principles in the Technical Barriers

to Trade (TBT) see the following URL: Foreword - Supplementary information

The committee responsible for this document is ISO/TC 67, Petroleum and Natural gas industries,

Subcommittee SC 4, Drilling and production equipment.
iv © ISO 2014 – All rights reserved
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SIST EN ISO 13354:2014
ISO 13354:2014(E)
Introduction

Drilling into shallow-gas-bearing formations is a very delicate and challenging operation. If the drilling

operations are seriously complicated by the reduced safety margin available between kick and loss, the

situation in case of a gas influx becomes extremely hazardous, due to a combination of the following

adverse factors.

— Shallow gas flows are extremely fast-developing events; there is only a short transition time

between influx detection and well unloading, resulting in a reduced time for the driller to take the

right decision, and leaving little room for error.

— Past blowout reports have disclosed the magnitude of severe dynamic loads applied to surface

diverting equipment. One of the associated effects is erosion, which adds a high potential for fire

and explosion due to flow impingement on rig facilities which gives the gas flow access to various

sources of ignition.

— Many past shallow-gas kicks turned into uncontrolled blowouts due to the failure of former diverter

systems installed several decades ago. Failure is seen as a result of the system’s complexity, its lack

of functional reliability and its inability to cope with the severe dynamic loads.

— Certain drilling supports are exposed to specific threats associated with shallow gas blowouts, e.g.

risk of cratering, risk of ship-shaped vessel capsize.

— Unprepared or inadequately trained drilling crews experience a high level of stress when facing a

violent shallow gas flow.

In the aftermath of shallow gas blowouts during the last four decades, comprehensive inquiries and

reports have been carried out, in particular by the specialists involved in combating these events, and

significant findings and conclusions have been published. In the meantime, the manufacturing industry

has developed various equipment aimed at significantly improving the safety of shallow-gas drilling

operations.

This International Standard has been prepared taking these aspects into consideration.

© ISO 2014 – All rights reserved v
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SIST EN ISO 13354:2014
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SIST EN ISO 13354:2014
INTERNATIONAL STANDARD ISO 13354:2014(E)
Petroleum and natural gas industries — Drilling and
production equipment — Shallow gas diverter equipment
1 Scope

This International Standard specifies requirements for the selection of the diverter equipment for rigs

used to drill shallow-gas-bearing formations. It covers both onshore and offshore drilling operations,

and considers also the auxiliary equipment associated with floating rigs.
The specified requirements concern the following diverter equipment:
— annular sealing devices;
— vent outlets;
— diverter valves;
— diverter piping.

This International Standard highlights the concerns associated with the selection of a marine floating

drilling support. It covers safety issues concerning key rig equipment, and important steps of action

required prior to starting the drilling operations.

It provides only general guidelines regarding the response to be given to a shallow-gas flow.

2 Normative references

The following documents, in whole or in part, are normatively referenced in this document and are

indispensable for its application. For dated references, only the edition cited applies. For undated

references, the latest edition of the referenced document (including any amendments) applies.

ISO 13533, Petroleum and natural gas industries — Drilling and production equipment — Drill-through

equipment

API 16D (latest revision), Specification for Control Systems for Drilling Well Control Equipment and Control

Systems for Diverter Equipment
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
actuator

device used to open or close a valve by means of applied manual, hydraulic, pneumatic or electrical

energy
3.2
annular packing element

doughnut-shaped rubber/elastomer element that creates a seal in an annular preventer or diverter

Note 1 to entry: The annular packing element is displaced toward the bore centre by the upward movement of an

annular piston.
© ISO 2014 – All rights reserved 1
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SIST EN ISO 13354:2014
ISO 13354:2014(E)
3.3
annular sealing device

torus-shaped steel housing containing an annular packing element which facilitates closure of the

annulus by constricting to seal on the pipe or kelly in the wellbore

Note 1 to entry: Some annular sealing devices also facilitate shutoff of the open hole.

3.4
bag preventer
device that can seal around any object in the wellbore or upon itself

Note 1 to entry: Compression of a reinforced rubber/elastomer packing element by hydraulic pressure creates

the seal.
3.5
ball valve
valve that employs a rotating ball to open or close the flow passage
3.6
blowout

uncontrolled flow of well fluids and/or formation fluids from the wellbore or into lower-pressured

subsurface zones

Note 1 to entry: When the uncontrolled flow of fluids goes into lower-pressured subsurface zones, it is termed an

underground blowout.
3.7
blowout preventer stack
BOP stack

device that allows the well to be sealed to confine the well fluids in the wellbore

3.8
bottom-supported marine structure

drilling structure supported by the soil on the seabed while in the operating mode

Note 1 to entry: Rigs of this type include fixed platforms, submersibles, swamp barges and jack-up drilling rigs.

3.9
cleanout

point in the flow-line piping where the internal area of the pipe can be accessed to remove accumulated

debris and drill cuttings
3.10
closing unit

assemblage of pumps, valves, lines, accumulators and other items necessary to open and close the BOP

equipment and diverter system
3.11
control function

control system circuit (hydraulic, pneumatic, electrical, mechanical, or a combination thereof) used to

operate the position selection of a diverter unit, BOP, valve or regulator
EXAMPLE Diverter “close” function, starboard vent valve “open” function.
3.12
control function

each position of a diverter unit, BOP or valve and each regulator assignment that is operated by the

control system
2 © ISO 2014 – All rights reserved
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SIST EN ISO 13354:2014
ISO 13354:2014(E)
3.13
diverter

device attached to the wellhead or marine riser to close the vertical access and to direct any flow into a

set of vent lines and away from the drilling unit
3.14
diverter control system

assemblage of pumps, accumulators, manifolds, control panels, valves, lines, etc., used to operate the

diverter system
3.15
diverter housing

permanent installation under the rotary table which houses the insert-type diverter assembly

3.16
diverter packer
annular sealing device of the diverter
3.17
diverter piping
vent lines of the diverter
3.18
diverter system

assemblage, comprising an annular sealing device, flow control means, vent system components and

control system, which facilitates closure of the upward flow path of the well fluid and opening of the

vent to the atmosphere
3.19
diverter unit
device that embodies the annular sealing device and its actuating means
3.20
drill floor substructure

foundation structure on which the derrick, rotary table, draw-works and other drilling equipment are

supported
3.21
drilling spool

flanged joint placed between the BOP and casing-head that serves as a spacer or crossover

3.22
drill ship
self-propelled, floating, ship-shaped vessel equipped with drilling equipment
3.23
dump valve

device used to control bottom-riser annulus pressure by establishing direct communication with the

sea
3.24
dynamically positioned drilling vessel
DP drilling vessel

drill-ship or semi-submersible drilling rig equipped with computer-controlled thrusters which enable it

to maintain a constant position relative to a fixed point on the sea floor without the use of anchors and

mooring lines while conducting floating drilling operations
3.25
elastomer
any of various elastic compounds or substances resembling rubber
© ISO 2014 – All rights reserved 3
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SIST EN ISO 13354:2014
ISO 13354:2014(E)
3.26
fill-up line

line, usually connected into the bell nipple above the BOP, to allow addition of drilling fluid to the hole

while simultaneously pulling out of the hole to compensate for the metal volume displacement of the

drill string being pulled
3.27
flex/ball joint

device installed directly above the subsea BOP stack and at the top of the telescopic riser joint to permit

relative angular movement of the riser, thus reducing stresses due to vessel motions and environmental

forces
3.28
flow-line
shaker line

piping that exits the bell nipple and conducts drilling fluid and cuttings to the shale shaker and drilling

fluid pits
3.29
formation fracture pessure

value of pressure required to initiate a fracture in a subsurface formation (geologic strata)

3.30
function test
closing and opening (cycling) equipment to verify operability
3.31
gate valve
valve that employs a sliding gate to open or close the flow passage
3.32
hydrostatic head
true vertical length of fluid column
3.33
hydrostatic pressure

pressure that exists at any point in the wellbore due to the weight of the vertical column of fluid above

that point
3.34
inner barrel

part of the telescopic slip joint on a marine riser that is attached to the flex joint beneath the diverter

3.35
insert-type packer

diverter element that uses inserts designed to close and seal on specific ranges of pipe diameter

3.36
integral valve

valve embodied in the diverter unit that operates integrally with the annular sealing device

3.37
interlock

arrangement of control system functions designed to require the actuation of one function as a

prerequisite to actuate another
4 © ISO 2014 – All rights reserved
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SIST EN ISO 13354:2014
ISO 13354:2014(E)
3.38
kelly

joint of pipe with flat or fluted sides that is free to move vertically through a bushing in the rotary table

Note 1 to entry: The bushing is termed a “kelly bushing”, and it imparts torque to the kelly thereby rotating the

drill string.
3.39
kick

influx of gas, oil or other well fluids which, if not controlled, can result in a blowout

3.40
kill mud

drilling fluid with sufficient mud weight used to overcome the borehole pressure in case of well influx

3.41
knife valve
valve using a portal plate or blade to facilitate open and close operations

Note 1 to entry: A knife valve differs from a gate valve in that the bonnet area is open, i.e. not sealed.

3.42
lost circulation
loss of drilling fluid to the wellbore
3.43
marine riser

extension of the well-bore from the subsea conductor pipe housing or wellhead to the floating drilling

vessel which provides for fluid returns to the drilling vessel and guides tools into the well

3.44
moored vessel

offshore floating drilling vessel which relies on anchors, chain and mooring lines extended to the ocean

floor to maintain a constant location relative to the ocean floor
3.45
mud line
floor of an ocean, lake, bay or swamp
3.46
outer barrel

part of the telescopic slip joint on a marine riser that is attached to tensioner lines

Note 1 to entry: Tension is transferred through the outer barrel into the riser.
3.47
pre-spud
period of time which precedes the start of drilling activities
3.48
poor-boy separator

pressure vessel designed to provide effective separation of gas from drilling fluid at atmospheric

pressure while circulating out a wellbore kick through the choke manifold
3.49
primary well control

prevention of formation fluid flow by maintaining a hydrostatic pressure equal to or greater than the

formation pressure
© ISO 2014 – All rights reserved 5
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SIST EN ISO 13354:2014
ISO 13354:2014(E)
3.50
production platform

permanently installed bottom-supported/connected offshore structure, fitted with drilling and/or

production equipment for drilling and/or development of offshore oil and gas reservoirs

3.51
riser hydraulic connector

hydraulic latch which connects the 762 mm (30 in) conductor pipe housing and the bottom of the marine

riser
Note 1 to entry: O-ring seals prevent leaks between the latch and the housing.
3.52
rotary table

device through which the bit and drill string pass and which transmits rotational action to the kelly

3.53
subsea diverter
seabed diverter

set-up of equipment attached to the bottom of the marine riser and connected to the 762 mm (30 in)

subsea wellhead housing, designed to close the well in case of shallow-gas influx and to direct it through

two subsea lateral vent outlets
3.54
semi-submersible

floating offshore drilling vessel which is ballasted at the drilling location and conducts drilling operations

in a stable, partly submerged position
3.55
target

bull plug or blind flange at the end of a tee to reduce erosion at a point where change in flow direction

occurs
3.56
targeted

having a type of fluid piping system in which flow impinges upon a lead (or other material)-filled end

(target) or a piping tee when the fluid flow changes direction
3.57
telescopic joint packer

torus-shaped, hydraulically, pneumatically or mechanically actuated, resilient element between the

inner and outer barrels of the telescopic joint which serves to retain drilling fluid inside the marine riser

3.58
vent line

conduit that directs the flow of diverted wellbore fluids away from the drill floor and to the atmosphere

3.59
vent line valve

full-opening valve which allows passage of diverted wellbore fluids through the vent line

3.60
vent outlet

point at which fluids exit the wellbore below the annular sealing device via the vent line

3.61
wellhead

apparatus or structure, placed on the top of the casings, that supports the internal tubular, seals the well

and permits access to the casing annulus
6 © ISO 2014 – All rights reserved
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SIST EN ISO 13354:2014
ISO 13354:2014(E)
3.62
working pressure rating
WP rating
maximum internal pressure that the equipment is designed to contain or control
4 Diverter system equipment
4.1 General purpose

The diverter system is designed to permit the drilling crew to blow down shallow-gas accumulations

downwind of the rig. Until a sufficient casing length has been set to allow a well to be shut-in during a kick,

the diverter system is the only line of defence, and is only expected to contain the hazard temporarily,

although as long as possible.

The diverter system is not intended to be a well-control device. It simply allows the flow to be diverted

in a safe manner in order to allow enough time to attempt regaining primary control of the well and,

should the latter fail, enough time for proper evacuation of the drilling crew or for proper move-off of

the drilling unit from the location (floating rigs), until the flow stops due to gas accumulation blow-

down, hole bridging, hole collapse, etc.
Traditional diverter system components comprise:
— the annular sealing device;
— vent outlet(s) and vent line(s);
— valves;
— the control system.
4.2 Findings of blowout reports

Blowout inquiries have concluded that the original designs underestimated the fact that shallow-gas

blowouts produce huge amounts of gas, together with abrasive solids, flowing at very high speed,

producing severe dynamic loads, and eroding and destroying many parts of the existing diverter

systems.

The failure of these diverter systems led unfortunately to the loss of many lives.

It is therefore of paramount importance to select suitable equipment able to function in a reliable and safe

manner, i.e. able to operate whenever required under the worst possible
...

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Industrija za predelavo nafte in zemeljskega plina - Vrtalna in proizvodna oprema - Oprema "Shallow gas diverter" (ISO/FDIS 13354:2013)Erdöl- und Erdgasindustrie - Shallow gas Diverterausrüstung (ISO/FDIS 13354:2013)Industries du pétrole et du gaz naturel - Équipements de forage et de production - Équipement déflecteur pour gaz de surface (ISO/FDIS 13354:2013)Petroleum and natural gas industries - Drilling and production equipment - Shallow gas diverter equipment (ISO/FDIS 13354:2013)75.180.10Oprema za raziskovanje in odkopavanjeExploratory and extraction equipmentICS:Ta slovenski standard je istoveten z:FprEN ISO 13354kSIST FprEN ISO 13354:2014en,fr,de01-januar-2014kSIST FprEN ISO 13354:2014SLOVENSKI

STANDARD
kSIST FprEN ISO 13354:2014

© ISO 2013Petroleum and natural gas industries — Drilling and production equipment — Shallow gas diverter equipmentIndustries du pétrole et du gaz naturel — Équipements de forage et quipement dé Ôlecteur pour gaz de surfaceINTERNATIONAL STANDARDPlease see the administrative notes on page iiiReference numberISO/FDIS 13354:2013(E)ISO/FDIS13354ISO/TC 67/SC 4Secretariat: ANSIVoting begins on: 2013-1Voting terminates on: 2014-0RECIPIENTS OF THIS DRAFT ARE INVITED TO SUBMIT, WITH THEIR COMMENTS, NOTIFICATION OF ANY RELEVANT PATENT RIGHTS OF WHICH THEY ARE AWARE AND TO PROVIDE SUPPOR TING DOCUMENTATION.IN ADDITION TO THEIR EVALUATION AS

BEING ACCEPTABLE FOR INDUSTRIAL, TECHNO­LOGICAL, COMMERCIAL AND USER PURPOSES, DRAFT INTERNATIONAL STANDARDS MAY ON OCCASION HAVE TO BE CONSIDERED IN THE LIGHT OF THEIR POTENTIAL TO BECOME STAN­DARDS TO WHICH REFERENCE MAY BE MADE IN NATIONAL REGULATIONS.FINALDRAFTkSIST FprEN ISO 13354:2014

ISO/FDIS 13354:2013(E) ii © ISO 2013 – All rights reservedCOPYRIGHT PROTECTED DOCUMENT©

ISO 2013All rights reservedä Unless otherwise speci Ðiedá no part of this publication may be reproduced or utilized otherwise in any form or by any meansá electronic or mechanicalá including photocopyingá or posting on the internet or an intranetá without prior written permissionä Permission can be requested from either ISO at the address below or ISOïs member body in the country of the requester.ISO copyright of ÐiceTel. + 41 22 749 01 11Fax + 41 22 749 09 47Eæmail copyright 7isoäorgWeb www.iso.orgPublished in SwitzerlandkSIST FprEN ISO 13354:2014

ISO/CEN PARALLEL PROCESSING­cessed under the ISO-lead mode of collaboration as de Ðined in the Vienna Agreementä The

Ðinal draft was established on the basis of comments received during a parallel enquiry on the draftäThis

Ðinal draft is hereby submitted to the ISO member bodies and to the CEN member bodies for a parallel two­month approval vote in ISO and formal vote in CEN.Positive votes shall not be accompanied by comments.Negative votes shall be accompanied by the relevant technical reasons.ISO/FDIS 13354:2013(E) © ISO 2013 – All rights reserved iiikSIST FprEN ISO 13354:2014

ISO/FDIS 13354:2013(E) iv © ISO 2013 – All rights reservedContents PageForeword ..........................................................................................................................................................................................................................................vIntroduction ................................................................................................................................................................................................................................vi1 Scope .................................................................................................................................................................................................................................12 Normative references ......................................................................................................................................................................................1FuFTermsFandFdeFÐinitions .....................................................................................................................................................................................14 Diverter system equipment .......................................................................................................................................................................64.1 General purpose .....................................................................................................................................................................................64.2 Findings of blowout reports ........................................................................................................................................................7 vä u Applications of diverter systems .............................................................................................................................................7 vä v Layout considerations — Land rigs and bottom­supported marine structures ............................8 vä w La ...........................................................................................................................18FwFFloatingFrigsFFSpeciFÐicFaspects .........................................................................................................................................................265.1 Use of the marine riser ..................................................................................................................................................................26 wä t Additional functions of the diverter system ...............................................................................................................28 wä u Comparison of types of

Ðloating support .......................................................................................................................286 Preparation for shallow gas operations ....................................................................................................................................316.1 Call for tender .......................................................................................................................................................................................316.2 Important issues .................................................................................................................................................................................316.3 Pre­spud checks ..................................................................................................................................................................................326.4 Pre­spud meetings ............................................................................................................................................................................346.5 Pre­spud drills ......................................................................................................................................................................................35 xä x Preparing the response to a shallowægas

Ðlow ..........................................................................................................367 Diverter system inspection and maintenance ....................................................................................................................397.1 General ........................................................................................................................................................................................................397.2 Maintenance ...........................................................................................................................................................................................397.3 Inspection and testing ...................................................................................................................................................................39 yä v Diverter system piping ..................................................................................................................................................................397.5 Manufacturer documentation .................................................................................................................................................40Bibliography .............................................................................................................................................................................................................................41kSIST FprEN ISO 13354:2014

ISO/FDIS 13354:2013(E)Forewordthrough ISO technical committeesä Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizationsá governmental and nonægovernmentalá in liaison with ISOá also take part in the workä electrotechnical standardizationäThe procedures used to develop this document and those intended for its further maintenance are described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the different types of ISO documents should be notedä This document was drafted in accordance with the editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rightsä ISO shall not be held responsible for identifying any or all such patent rightsä Details of any the ISO list of patent declarations received (see www.iso.org/patents).Any trade name used in this document is information given for the convenience of users and does not constitute an endorsement.For an explanation on the meaning of ISO speci Ðic terms and expressions related to conformity assessment, as well as information about ISO’s adherence to the WTO principles in the Technical Barriers The committee responsible for this document is ISO/TC 67, Petroleum and Natural gas industries, Subcommittee SC 4, Drilling and production equipment. © ISO 2013 – All rights reserved vkSIST FprEN ISO 13354:2014

ISO/FDIS 13354:2013(E)IntroductionDrilling into shallowægasæbearing formations is a very delicate and challenging operationä If the drilling operations are seriously complicated by the reduced safety margin available between kick and lossá the situation in case of a gas in Ðlux becomes extremely hazardousá due to a combination of the following adverse factors. Shallow gas

Ðlows are extremely fastædeveloping eventsâ there is only a short transition time between in Ðlux detection and well unloadingá resulting in a reduced time for the driller to take the right decision, and leaving little room for error. Past blowout reports have disclosed the magnitude of severe dynamic loads applied to surface diverting equipmentä One of the associated effects is erosioná which adds a high potential for

Ðire and explosion due to
Ðlow impingement on rig facilities which gives the gas

Ðlow access to various sources of ignition. Many past shallowægas kicks turned into uncontrolled blowouts due to the failure of former diverter systems installed several decades agoä Failure is seen as a result of the systemïs complexityá its lack of functional reliability and its inability to cope with the severe dynamic loadsä Certain drilling supports are exposed to speci Ðic threats associated with shallow gas blowoutsá eägä risk of crateringá risk of shipæshaped vessel capsizeä Unprepared or inadequately trained drilling crews experience a high level of stress when facing a violent shallow gas

ÐlowäIn the aftermath of shallow gas blowouts during the last four decades, comprehensive inquiries and reports have been carried outá in particular by the specialists involved in combating these eventsá and signi Ðicant

Ðindings and conclusions have been publishedä In the meantimeá the manufacturing industry has developed various equipment aimed at signi Ðicantly improving the safety of shallowægas drilling operationsäThis International Standard has been prepared taking these aspects into consideration. vi © ISO 2013 – All rights reservedkSIST FprEN ISO 13354:2014

Petroleum and natural gas industries — Drilling and production equipment — Shallow gas diverter equipment1 ScopeThis International Standard speci Ðies requirements for the selection of the diverter equipment for rigs used to drill shallow­gas­bearing formations. It covers both onshore and offshore drilling operations, and considers also the auxiliary equipment associated with

Ðloating rigsäThe speci Ðied requirements concern the following diverter equipmentã annular sealing devicesâ vent outletsâ diverter valvesâ diverter pipingäThis International Standard highlights the concerns associated with the selection of a marine

Ðloating drilling supportä It covers safety issues concerning key rig equipmentá and important steps of action required prior to starting the drilling operations.It provides only general guidelines regarding the response to be given to a shallowægas

Ðlowä2 Normative referencesThe following documentsá in whole or in partá are normatively referenced in this document and are indispensable for its applicationä For dated referencesá only the edition cited appliesä For undated ISO 13533, Petroleum and natural gas industries — Drilling and production equipment — Drill-through equipmentAPI 16D (latest revision), Speci Ôication for Control Systems for Drilling Well Control Equipment and Control Systems for Diverter EquipmentFuFTermsFandFdeFÐinitionsFor the purposes of this documentá the following terms and de Ðinitions applyä3.1actuatordevice used to open or close a valve by means of applied manualá hydraulicá pneumatic or electrical energy3.2annular packing elementdoughnut­shaped rubber/elastomer element that creates a seal in an annular preventer or diverterNote

s to entryã The annular packing element is displaced toward the bore centre by the upward movement of an annular piston.FINAL DRAFT INTERNATIONAL STANDARD ISO/FDIS 13354:2013(E)© ISO 2013 – All rights reserved 1kSIST FprEN ISO 13354:2014

ISO/FDIS 13354:2013(E)3.3annular sealing devicetorus­shaped steel housing containing an annular packing element which facilitates closure of the annulus by constricting to seal on the pipe or kelly in the wellboreNote

s to entryã Some annular sealing devices also facilitate shutoff of the open holeä3.4bag preventerdevice that can seal around any object in the wellbore or upon itselfNote

s to entryã Compression of a reinforced rubber/elastomer packing element by hydraulic pressure creates the sealä3.5ball valvevalve that employs a rotating ball to open or close the

Ðlow passage3.6blowoutsubsurface zonesNote
s to entryã When the uncontrolled
Ðlow of

Ðluids goes into loweræpressured subsurface zonesá it is termed an underground blowout.3.7blowout preventer stackBOP stackdevice that allows the well to be sealed to con Ðine the well

Ðluids in the wellbore3.8bottom-supported marine structuredrilling structure supported by the soil on the seabed while in the operating modeNote

s to entryã Rigs of this type include

Ðixed platformsá submersiblesá swamp barges and jackæup drilling rigsä3.9cleanoutpoint in the

Ðlowæline piping where the internal area of the pipe can be accessed to remove accumulated debris and drill cuttings3.10closing unitassemblage of pumpsá valvesá linesá accumulators and other items necessary to open and close the BOP equipment and diverter system3.11control functionoperate the position selection of a diverter unit, BOP, valve or regulatorEXAMPLE Diverter “close” function, starboard vent valve “open” function.3.12control functioneach position of a diverter unitá BOP or valve and each regulator assignment that is operated by the control system3.13diverterdevice attached to the wellhead or marine riser to close the vertical access and to direct any

Ðlow into a set of vent lines and away from the drilling unit 2 © ISO 2013 – All rights reservedkSIST FprEN ISO 13354:2014

ISO/FDIS 13354:2013(E)3.14diverter control systemassemblage of pumps, accumulators, manifolds, control panels, valves, lines, etc., used to operate the diverter system3.15diverter housingpermanent installation under the rotary table which houses the insertætype diverter assembly3.16diverter packerannular sealing device of the diverter3.17diverter pipingvent lines of the diverter3.18diverter systemassemblageá comprising an annular sealing deviceá

Ðlow control meansá vent system components and control systemá which facilitates closure of the upward

Ðlow path of the well

Ðluid and opening of the vent to the atmosphere3.19diverter unitdevice that embodies the annular sealing device and its actuating means3.20drillFFÐloorFsubstructurefoundation structure on which the derrická rotary tableá drawæworks and other drilling equipment are supported3.21drilling spool Ðlanged joint placed between the BOP and casingæhead that serves as a spacer or crossover3.22drill shipselfæpropelledá

Ðloatingá shipæshaped vessel equipped with drilling equipment3.23dump valvedevice used to control bottomæriser annulus pressure by establishing direct communication with the sea3.24dynamically positioned drilling vesselDP drilling vesseldrill­ship or semi­submersible drilling rig equipped with computer­controlled thrusters which enable it to maintain a constant position relative to a

Ðixed point on the sea
Ðloor without the use of anchors and mooring lines while conducting

Ðloating drilling operations3.25elastomerany of various elastic compounds or substances resembling rubber3.26FÐillæupFlinelineá usually connected into the bell nipple above the BOPá to allow addition of drilling

Ðluid to the hole while simultaneously pulling out of the hole to compensate for the metal volume displacement of the drill string being pulled © ISO 2013 – All rights reserved 3kSIST FprEN ISO 13354:2014

ISO/FDIS 13354:2013(E)3.27Fjointdevice installed directly above the subsea BOP stack and at the top of the telescopic riser joint to permit relative angular movement of the riser, thus reducing stresses due to vessel motions and environmental forces3.28FÐlowælineshaker linepiping that exits the bell nipple and conducts drilling

Ðluid and cuttings to the shale shaker and drilling

Ðluid pits3.29formation fracture pessurevalue of pressure required to initiate a fracture in a subsurface formation (geologic strata)3.30function test3.31gate valvevalve that employs a sliding gate to open or close the

Ðlow passage3.32hydrostatic headtrue vertical length of

Ðluid column3.33hydrostatic pressurepressure that exists at any point in the wellbore due to the weight of the vertical column of

Ðluid above that point3.34inner barrelpart of the telescopic slip joint on a marine riser that is attached to the

Ðlex joint beneath the diverter3.35insert-type packerdiverter element that uses inserts designed to close and seal on speci Ðic ranges of pipe diameter3.36integral valvevalve embodied in the diverter unit that operates integrally with the annular sealing device3.37interlockarrangement of control system functions designed to require the actuation of one function as a prerequisite to actuate another3.38kellyjoint of pipe with

Ðlat or

Ðluted sides that is free to move vertically through a bushing in the rotary tableNote

s to entryã The bushing is termed a òkelly bushingóá and it imparts torque to the kelly thereby rotating the drill string.3.39kickin Ðlux of gasá oil or other well

Ðluids whichá if not controlledá can result in a blowout 4 © ISO 2013 – All rights reservedkSIST FprEN ISO 13354:2014

ISO/FDIS 13354:2013(E)3.40kill muddrilling

Ðluid with suf Ðicient mud weight used to overcome the borehole pressure in case of well in Ðlux3.41knife valvevalve using a portal plate or blade to facilitate open and close operationsNote

s to entryã A knife valve differs from a gate valve in that the bonnet area is opená iäeä not sealedä3.42lost circulationloss of drilling

Ðluid to the wellbore3.43marine riserextension of the wellæbore from the subsea conductor pipe housing or wellhead to the

Ðloating drilling vessel which provides for

Ðluid returns to the drilling vessel and guides tools into the well3.44moored vesseloffshore

Ðloating drilling vessel which relies on anchorsá chain and mooring lines extended to the ocean

Ðloor to maintain a constant location relative to the ocean

Ðloor3.45mud line Ðloor of an oceaná lakeá bay or swamp3.46outer barrelpart of the telescopic slip joint on a marine riser that is attached to tensioner linesNote

s to entryã Tension is transferred through the outer barrel into the riserä3.47pre-spudperiod of time which precedes the start of drilling activities3.48poor-boy separatorpressure vessel designed to provide effective separation of gas from drilling

Ðluid at atmospheric pressure while circulating out a wellbore kick through the choke manifold3.49primary well controlprevention of formation

Ðluid

Ðlow by maintaining a hydrostatic pressure equal to or greater than the formation pressure3.50production platformproduction equipment for drilling and/or development of offshore oil and gas reservoirs3.51riser hydraulic connectorhydraulic latch which connects the

y x t m iriserNote

s to entryã Oæring seals prevent leaks between the latch and the housingä © ISO 2013 – All rights reserved 5kSIST FprEN ISO 13354:2014

ISO/FDIS 13354:2013(E)3.52rotary tabledevice through which the bit and drill string pass and which transmits rotational action to the kelly3.53subsea diverter seabed diverterset­up of equipment attached to the bottom of the marine riser and connected to the 762 mm (30 in) subsea wellhead housingá designed to close the well in case of shallowægas in Ðlux and to direct it through two subsea lateral vent outlets3.54semi-submersible Ðloating offshore drilling vessel which is ballasted at the drilling location and conducts drilling operations in a stableá partly submerged position3.55targetbull plug or blind

Ðlange at the end of a tee to reduce erosion at a point where change in

Ðlow direction occurs3.56targeted3.57telescopicFjointFpackertorusæshapedá hydraulicallyá pneumatically or mechanically actuatedá resilient element between the inner and outer barrels of the telescopic joint which serves to retain drilling

Ðluid inside the marine riser3.58vent lineconduit that directs the
Ðlow of diverted wellbore
Ðluids away from the drill

Ðloor and to the atmosphere3.59vent line valvefullæopening valve which allows passage of diverted wellbore

Ðluids through the vent line3.60vent outletpoint at which

Ðluids exit the wellbore below the annular sealing device via the vent line3.61wellheadapparatus or structure, placed on the top of the casings, that supports the internal tubular, seals the well and permits access to the casing annulus3.62working pressure ratingWP ratingmaximum internal pressure that the equipment is designed to contain or control4 Diverter system equipment4.1 General purposeThe diverter system is designed to permit the drilling crew to blow down shallowægas accumulations downwind of the rigä Until a suf Ðicient casing length has been set to allow a well to be shutæin during a kická

6 © ISO 2013 – All rights reservedkSIST FprEN ISO 13354:2014

ISO/FDIS 13354:2013(E)the diverter system is the only line of defenceá and is only expected to contain the hazard temporarilyá although as long as possible.The diverter system is not intended to be a wellæcontrol deviceä It simply allows the

Ðlow to be diverted in a safe manner in order to allow enough time to attempt regaining primary control of the well andá should the latter fail, enough time for proper evacuation of the drilling crew or for proper move­off of down, hole bridging, hole collapse, etc.Traditional diverter system components compriseã the annular sealing deviceâ v valvesâ the control systemä4.2 Findings of blowout reportsBlowout inquiries have concluded that the original designs underestimated the fact that shallow­gas blowouts produce huge amounts of gasá together with abrasive solidsá

Ðlowing at very high speedá producing severe dynamic loadsá and eroding and destroying many parts of the existing diverter systemsäThe failure of these diverter systems led unfortunately to the loss of many livesäIt is therefore of paramount importance to select suitable equipment able to function in a reliable and safe manner, i.e. able to operate whenever required under the worst possible conditions. Diverter equipment shall also be able to cope with the prevailing dynamic loads and associated effectsäThe most frequent

Ðindings from blowout reports are as followsä Insertætype diverters have too many componentsä The locking mechanism of insertætype diverters is not really designed to contend with severe dynamic loadsä Insertætype diverter packers cannot close on openæhole and on some drilling assembliesä Pistonæactuated bag preventers are stronger and less complexá but close too slowlyä Diverter outlets often promote erosionä Diverter vent lines are usually thinæwalledá too small in diameterá have a tortuous pathá and are inadequately supportedá fastened and securedä Some valve systems are inadequate and unreliableä Layouts for control systems are too complexä Power sources of some control systems are not reliableä The maintenance of diverter systems is not given the same importance compared to BOPsä4.3 Applications of diverter systemsDiverters are primarily used to divert

Ðlow from the rig in three situationsã shallow
Ðluid and gas

Ðlowsâ drilling with a rotating headâ © ISO 2013 – All rights reserved 7kSIST FprEN ISO 13354:2014

ISO/FDIS 13354:2013(E) drilling with a marine riseräThis International Standard will not discuss the speci Ðic aspects associated with rotatingæhead drillingä4.4 Layout considerations — Land rigs and bottom-supported marine structures4.4.1 GeneralDrilling operations into shallow­gas­bearing formations include drilling from a land rig, or from a marine structure supported by a matætype baseá by legsá or drilling from a barge that rests on the bottomá eägä jackæup drilling rigsá production platforms rigs and swampæbarge rigsäLand rigs and bottom­supported marine structures have at their disposal a wide range of equipment to build diverter arrangements.4.4.2 Types of annular sealing devices in use4.4.2.1 Insert-type diverter assemblyIn the insertætype diverter assemblyá the insert packing is latched in place into a diverter assemblyá which in turn is locked inside the support housing. This housing provides two outlets, one for the mud returns Figure 1).The rig substructure and the diverter assembly locking dogs shall be able to withstand the upward forces of the diverted

Ðluidä4.4.2.2 Annular packing elementTFigure 2).The connections shall be in accordance with the applicable provisions of ISO 13533. The annular packing element should be of suf Ðicient internal diameter to pass the various bottomæhole assemblies and casing/liner strings required for subsequent drilling operations.NOTE For the purposes of this provision, ANSI/API 16A is equivalent to ISO 13533. 8 © ISO 2013 – All rights reservedkSIST FprEN ISO 13354:2014

ISO/FDIS 13354:2013(E)Key1insert packing2piston3support housing4 Ðlow line outlet5vent line outletFigureFFsFFExampleFofFinsertætypeFdiverterFassembly © ISO 2013 – All rights reserved 9kSIST FprEN ISO 13354:2014

ISO/FDIS 13354:2013(E)5231466789Key1 bell nipple t
Ðlow line u

Ðillæup line4 annular packing element w standard bagætype preventer6 vent line7 diverter spool z hydraulically operated full opening valve9 drive/conductor pipeFigureFFtFFExampleFofFdiverterFassemblyFwithFannularFpackingFelement4.4.2.3 Comparison of systemsThe two systems can be compared as followsä Insertætype diverter assembly 10 © ISO 2013 – All rights reservedkSIST FprEN ISO 13354:2014

ISO/FDIS 13354:2013(E) Advantagesã quick assemblyâ
Ðlowælineá

Ðillæup line and vent line permanently hooked upâ faster shutæin timeâ light equipmentá not cumbersomeä Drawbacksã the insertætype diverter system cannot withstand more than

v v y k ppackerâ this can be a problem when coping with severe gas

Ðlowsâ insertætype packer never providing complete packæoff on open holeâ requires a signi Ðicant number of valvesá adding potential failure pointsâ requires complex sequencing operations and interlocks to activate the vent and

Ðlowæline valvesâ rperform the closing sequenceá adding potential failure pointsâ location likely to create potential erosion points in the

Ðlowæline if the latter is not properly designedâ overshot packer located below the diverter systemá hence exposed to shallow gas

Ðlowâ ease of hookæup is largely outweighed by the potential for failure and leaksä Classical annular packing assembly Advantagesã d reduced number of remotely controlled valvesá due to the system position directly on top of the

Ðirst casing and below the

Ðlowælineâ fullæbore closing capacity often availableâ no more overshot packer exposed to gas

Ðlow pressure below the diverter systemä Drawbacksã cumbersome equipmentâ longer nipplingæup and nippleædown operationsá hence including more initial expenseâ vent lines require handling and adjustmentá excessive closing time of packing elementä4.4.2.4 Requirements for safe operation4.4.2.4.1 GeneralSafe operation requires a standard hookæup including a bagætype preventerá together with a twoæoutlet The bag preventer shall be full­bore closing, with adequate internal diameter, and the response time kept equal to or even below the value given in API

s xDä This can be achieved by means of eägä bigger control lines, twin control lines, boosters. © ISO 2013 – All rights reserved 11kSIST FprEN ISO 13354:2014

ISO/FDIS 13354:2013(E)Different sizes of bagætype preventers existá eägä from
w r z mm to
y v {á u m i idifferent pressure
...