Hoat Dong Hang Hai DNV

DNV Marine Operations

DNV-OS-H203 - Transit and Positioning of Offshore Units

Arve Lepsøe / Per Øystein Alvær

09.11.2011

Innhold

Generelt (kort) om

oppdateringen av DNV marine

operasjons reglene!

Gjennomgang av innholdet i

DNV-OS-H203 med vekt på:

o Hva er nytt/oppdatert i H203

sammenlignet med VMO-

Reglene Pt.2 Ch.7 (Transit

and Positioning of Mobile

Offshore Units)

o Henvisninger til krav i DNV-

OS-H101 (Marine

Operations, General) som er

relevante for DNV-OS-H203

Version Slide 2 07 November 2011


F A B C D E

Rules to Standards – DNV Offshore Codes

Recommended Practices

Offshore Service Specifications

H

Offshore Standards


Rules to Standards – Overview (1)

DNV-OS-H102

Design & Fabr.

Pt.1 Ch.2

Pt.1 Ch.3

Pt.1 Ch.4

DNV-OS-H101

General

DNV-OSS-902 Marine Operations

Pt.0 Ch.1

Pt.1 Ch.1

User Information

Warranty Surveys

Planning of

Operations

Design Loads

Structural Design

Towing

Special Sea

Transportation

Risk based

verification

α-factor (JIP)

Load definitions

NDT (waiting time)

Friction

Pt.2 Ch.1

DNV-OS-H201

Load Transfer

Pt.2 Ch.3

Pt.2 Ch.2 DNV-OS-H202

Sea Transport

Load Transfer Operations JIP – Transport

Fatigue

Ship/HLV transports

elaborated

Seafastening

Rule Section New Standard Main Input/updates


Rules to Standards – Overview (2)

Pt.2 Ch.4

DNV-OS-H204

Offshore Inst.

Pt.2 Ch.5

DNV-OS-H205

Lifting

Pt.2 Ch.6

DNV-OS-H206

Subsea

Pt.2 Ch.7

DNV-OS-H203

Rig Moves

Offshore

Installation

Lifting

Sub Sea

Operations

Transit and

Positioning of

MOU

General update

Use of soft rope slings

Small lifts (<50 tonnes)

Sling safety factor

Complete update

MWS for Pipe laying.

Installation of umbilicals, spools, etc.

Safety factors fibre- & wire ropes.

Subsea installation systems

DNV-RP-H103

Lay-out update

Pre-laid anchors

Clearances

DP elaborated

Hook-up of FPSO’s

Lay-out update

Suction anchors


Rules to Standards – Status

DNV-OSS-902 Marine Operations

DNV-OS-H101 General

DNV-OS-H102 Design & Fabrication

DNV-OS-H201 Load Transfer

DNV-OS-H202 Sea Transport

DNV-OS-H204 Offshore Inst.

DNV-OS-H205 Lifting

DNV-OS-H206 Subsea

DNV-OS-H203 Rig Moves

NA

Hearing completed

Hearing completed

Nov-11

Jan-11

On hearing

Nov-11

Dec-11

Dec-11

New DNV Offshore Code Hearing

Oct-12

Issued

Dec-11

Mar-12

Apr-12

Feb-12

Mar-12

Apr-12

Apr-12

Planned

issued


OFFSHORE STANDARD

DNV-OS-H203

Transit and Positioning of

Offshore Units

FEBRUARY 2012

The electronic pdf version of this document found through http://www.dnv.com is the officially binding version

DET NORSKE VERITAS AS

VMO Rules Pt.2 Ch.7 to DNV-OS-H203

Text Lay-out and Distribution

DNV-OS-H203

Text columns: 1

Available on paper: No

On DNV homepage: Yes,

for free

Sections: 6

Text pages: 29

Paragraphs: 936

Words: 11 190

VMO-Rules Pt.2 Ch.7

Text columns: 2

Available on paper: Yes

for NOK 2.500 (Complete)

On DNV homepage: No

Sections: 4

Text pages: 13

Paragraphs: 507

Words: 6 785


Section Numbers and Titles

DNV-OS-H203 VMO-Rules Pt.2 Ch.7


Section 1 - Introduction

Section 2 – Planning and

Preparations

Section 3 - Transit

Section 4 - Positioning

Section 1 - Introduction

Section 2 – General

Requirements

Section 3 – Transit

Section 4 – Anchored

Units

Section 5 – Dynamically

Positioned Units

Section 6 – Self-

Elevating Units

Main References to Other Codes

DNV-OS-H203

New DNV OS (and RPs) for

Marine Operations

DNV-OSS-101 (DNV Rules for

Classification)

DNV-OS-C104 (Self-elv. Units)

DNV-OS-E301 Positioning

Mooring

DNV-OS-E302/E303/E304 & DNV-

RP-E301/E302 & E307 (Mooring lines,

anchors & DP)

VMO-Rules Pt.2 Ch.7

Other parts of VMO-Rules (DNV Rules for Planning and

Execution of Marine Operations)

DNV Rules for

Classifications of MOU

DNV-RP-E301/E302 (Anchor design and installation)


IMO MSC/Circ. 645

ISO 19901-7

API RP 2SK

NMD Reg. 10/70/09

DNV-OS-H203 Sec.1 - Introduction

Section 1 and called Introduction in Pt.2 Ch.7 as well

Application: Wording changed from …Mobile Offshore Units to

…Offshore Units for the positioning phase. (NB: and also on the

document itself!)

List(s) of references and conditions for use included.

Definitions: Updated/expanded…..Shall/should defined.


DNV-OS-H203 Section 2

Title and sub-titles modified

Content updated/expanded

Risk management included under own heading


DNV-OS-H203 Section 3 - Transit

Title as in Pt.2 Ch.7

Content updated/expanded/re-

arranged

The requirements to emergency

(safe) jack up locations moved to

new section 6


Definition of temporary safe condition slightly modified, 10year

return criteria based on actual TR.

Requirements to planning phase elaborated.

Section 4 – Anchored Units


Requirements to 3 types of

mooring categories clarified

(illustrated on own slide

covering drag installed

anchors)

Requirements to clearances

updated (own slides)

Connection to pre-laid

mooring (included mainly to

cover hook-up of FPSOs)


Mooring category

1

Long-term or

permanent mooring

2

Mobile mooring

3

Weather restricted

mooring

Mooring period, P P > 5 years P < 5 years P = Operation reference

period (TR)

Typical unit involved Production/storage

unit or loading buoy

Drilling unit and

accommodation unit.

Installation vessel,

SSCV

Theoretical verification of

anchor resistance

As required by national governmental

regulations, or as given in:

DNV-OS-E301, DNV-RP-E301 and DNV-RP-

E302,

or equivalent recognised code/standard.

Calculations normally

not required. See ‎503

and ‎504.

Minimum test load and

procedure for verification

(testing) of anchor resistance

as installed on actual location

As approved in the anchor design. Any

applicable national governmental regulations to

be considered.

1.25 times the maximum

calculated line tension.

Maximum test load

Chain cable: Maximum of chain proof load and 0.66 MBL

Steel wire or fibre rope: 0.66 MBL

Minimum time for test load 15 minutes

Drag installed anchors - Summary

Survey interval

row removed

New name

Updated

Moved


Units/structures

involved

Text

references1)

Clearance during

positioning

Clearance in normal

operation

Vertical Horizontal Vertical Horizontal

Floating and fixed

units, or two floating

units

See ‎402

50 m

See ‎402

ALS: 10 m

Floating and fixed

units, or two floating

units, weather

restricted operations

‎C 300 50 m ULS: 5 m

ALS: 3 m

1) See ‎C 100 for general requirements in addition to the indicated text references.

402 The horizontal minimum clearances shall be maintained for all possible relative

vertical positions, including motions, between the units.

Clearances for Anchored Units

E.g. C104: Maximum motions due to the design environmental conditions during

the operation shall be considered in order to establish sufficient clearance.

Requirements to self-elevating units removed from table


Units/structures and

mooring elements involved

Text

references1)

Clearance during positioning Clearance in normal operation

Vertical Horizontal Vertical Horizontal

Line and a “hot” unit ‎502 30 m ULS: 10 m

ALS: No contact

Line and a “cold” unit ‎502 & ‎506 10 m ULS: 5 m

ALS: See ‎506

Line and a “hot” riser Infinite, i.e.

no crossing 150 m

Infinite, i.e. no

crossing

ULS: 100 m

ALS: 30 m

Line and unprotected

pipeline3) ‎503 30 m 150 m

ULS: 20 m

ALS: No

contact

ULS: 100 m

ALS: No

contact

Line and protected

pipeline3) ‎503 & ‎507 10 m 50 m

ULS: 10 m

ALS: See text

ULS: 50 m

ALS: See text

Line and sub-sea structure ‎509 Infinite, i.e.

no crossing 150 m

Infinite, i.e. no

crossing

ULS: 100 m

ALS: 50 m

Lines of two or more units ‎505 & ‎508 20 m - ULS: 10 m

ALS: See text -

Anchor and pipeline3) (line

crossing pipeline)

‎602 & ‎603 See ‎D.103

& ‎D.104

250 m - 250 m

Anchor and pipeline3) (line

not crossing pipeline) 150/50 m - 150/50 m

Anchor and sub-sea

structure 300/50 m - 300/50 m

Clearances for Lines & Anchors


No line area

Horizontal minimum clearance (H)

Vertical

minimum

clearance

(V) 30% of V

70% of H pipeline

Combined (V & H) Clearances

2_

2_ clearanceHorizontalclearanceVertical

502 The minimum clearances between lines and platforms (units) are in any direction, i.e.

≥ minimum clearance.

503 Between lines and pipelines linear relationship between vertical and horizontal

clearances should be assumed. E.g. if the horizontal clearance is 70% of the required

minimum clearance the vertical clearance should be ≥ 30% of the minimum vertical

clearance corresponding to zero horizontal clearance. See Figure 4 1.

Pt.2 Ch.7

Section 5 – Dynamically Positioned Units

Pt.2 Ch.7 included only some general references, while DNV-OS-

H203 is detailing (through references were relevant) requirements to:

- Design conditions & design evaluations

- Planning and documentation

- DP operation versus DP equipment class (own slide)

- Field arrival

- Complex and close proximity DP operations

- Contingencies

- Annual DP trial

- Checklists

- Operational aspects



ACTIVITY CLASS a) Manned underwater operations (high risk) 3

b) Other manned underwater operations 2

c) Support vessels for manned underwater operations conducted

from work boats 2

d) Drilling and well activities 3

e) Facilities that produce hydrocarbons 3

f) Flotels with gangway connected 3

g) All activities within the safety zone 2

h) Activities with limited clearance to the facility where the vessel

represents a risk to the facility 3

i) Loading operations from FSUs and FPSOs (tank vessels) 2

j) Loading operations from buoys 1

k) Other well activities 2

l) Shallow drilling 1

DP equipment class selection

Section 6 – Self-Elevating Units

The technical content regarding self-elevating units is

not significantly updated.


The content has been

considerably re-arranged.

References to planning and

documentation requirements

are included/clarified.

Reference to general

operational requirements in

DNV-OS-H101 included.


101 Transit and positioning operations shall be planned and documented according to the requirements and

philosophies given in DNV-OS-H101, Section 2.

Guidance Note Extent of planning and documentation for a specific transit and/or positioning operation should reflect the operation complexity and existing experience with similar operations.

DNV-OS-H101 - Planning

A 100 Philosophy

101 Marine operations shall be planned according to safe and sound

practice, and according to defined codes and standards.

102 A marine operation shall be designed to bring an object from one

defined safe condition to another.

Guidance note:

“Safe Condition” is defined as a condition where the object is considered exposed to

normal risk (i.e. similar risk as expected during in-place condition) for damage or loss.

Mange andre krav som kan/må sees i sammenheng med GN


DNV-OS-H101 - Environmental Conditions

Some applicable items:

How to consider seasonal variations, e.g.:

February March April

Operation period

Return period to be considered based on reference period:

Reference Period, TR Return Period, Td

TR 3 days Td ≥ 1 month

3 days < TR 7 days Td ≥ 3 months

7 days < TR 30 days Td ≥ 1 year

30 days < TR 180 days Td ≥ 10 years

TR > 180 days Td ≥ 100 years


DNV-OS-H101 - Operation Periods

WF WF WF WF (Weather forecast issued) Operation starts

TPOP TC

TR

(Basis for selecting α-factor)

Required weather window with OPWF ≤ α x OPLIM

Estimated time for the operation

TR = Operation reference period

TPOP = Planned operation period

TC = Estimated maximum contingency time


Operational Limiting Criteria

The OPLIM (Limiting operational environmental criteria)

shall never be taken greater than the minimum of:

- The environmental design criteria.

- Maximum wind and waves for safe working- or transfer conditions for

personnel.

- Equipment (e.g. ROV and cranes) specified weather restrictions.

- Limiting weather conditions of diving system (if any).

- Limiting conditions for position keeping systems.

- Any limitations identified, e.g. in HAZID/HAZOP, based on operational

experience with involved vessel(s) etc.

The forecasted (monitored) operational criteria - OPWF

- is defined as OPWF = α x OPLIM.


DNV-OS-H101 - Alpha Factors

Operational

Period [h]

Design Wave Height [m]

Hs = 1 1 < Hs < 2 Hs =2= 2 2 < Hs < 4 Hs = 4 4 < Hs < 6 Hs ≥ 6

TPOP ≤‎12 0.65

Lin

ear

Inte

rpo

lati

on

0.76

Lin

ear

Inte

rpo

lati

on

0.79

Lin

ear

Inte

rpo

lati

on

0.80

TPOP ≤‎24 0.63 0.73 0.76 0.78

TPOP ≤‎36 0.62 0.71 0.73 0.76

TPOP ≤‎48 0.60 0.68 0.71 0.74

TPOP ≤‎72 0.55 0.63 0.68 0.72

The alpha factor for waves is defined by 5 Tables, below “Base Case”:

The other tables take into account combinations of

o Wave monitoring

o Weather forecast level

o Meteorologist at site

WWW.dnv.no (WWW.dnv.com)


http://www.dnv.no/


Any Questions?

Request for receiving DNV-OS-H203 for comments in the hearing period:

[email protected]

DNV-OS-H203 for Comments

© Det Norske Veritas AS. All rights reserved.

DNV Alpha factor

07 February 2011

CONFIDENTIAL

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