ADVANCES IN UNDERWATER TECHNOLOGY,

OCEAN SCIENCE AND OFFSHORE ENGINEERING

Volume 5

Submersible Technology

ADVANCES IN UNDERWATER TECHNOLOGY, OCEAN SCIENCE AND OFFSHORE ENGINEERING

Vol. 1 Developments in Diving Technology Vol. 2 Design and Installation of Subsea Systems Vol. 3 Offshore Site Investigation Vol. 4 Evaluation, Comparison and Calibration of

Oceanographic Instruments Vol. 5 Submersible Technology

ORGANISING COMMITTEE

Sir John Rawlins - Chairman

K. T. Bentley - Phillips Petroleum Co E-A Ltd

F. Bruen - Underwater Security Consultants Ltd

J. Dering - Ad1lliralty Research Establishment

C. Logan - Association of Offshore Diving Contractors

R. Mavin - Department of Enwf'gy

R. Marsh - Bennico Ltd

D. J. Partridge - British Underwater Engineering Ltd

D. W. Partridge - Qffshore Supplies Qffice

J. Pritchard - Society for Underwater Technology

D. Wardle - Society for Underwater Technology

T. A. Hollobone - Chairman

F. J. Alexander - Total Oil Marine pIc

N. Chambers - Sub Sea QffshoTe Ltd

S. Davey - COIIIKC Houlder Diving Ltd

J. E. Hendrick - Shell UK Exploration & Production Ltd

G. Mills - Oceaneering International Services Ltd

C. Smith - Wharton Williams

J. Smith - Che1J)"on Petl'Olelilll (UK) Ltd

G. Watson - BP Pet. Dev. Ltd.

First published in 1986 by

Graham & Trotman Limited Sterling House 66 Wilton Road London SWIV IDE UK

Graham & Trotman Inc. 13 Park Avenue Gaithersburg MD 20877 USA

British Library Cataloguing Publication Data

Subtech '85 (C01~ference: Aberdeen) Submersible technology: proceedings of an international conference (Sub tech '85).­(Advances in underwater technology, ocean science and offshore enginering, v. 5) 1. Ocean Engineering 2. Underwater construction I. Title II. Society for Underwater Technology III. Series 627'.7 TCI645

ISBN-13: 978-94-010-8365-2 e-ISBN-13: 978-94-009-4203-5 DOl: 10.1007/978-94-009-4203-5

Libra1!! of Congress Cataloging in Publication Data is available.

© Society for Underwater Technology 1986

This -publication is protected by international copyright laws. All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording or otherwise, without the prior permission of the publishers.

by Robert Hartnoll (1985) Ltd., Bodmin, Cornwall

ADVANCES IN UNDERWATER TECHNOLOGY,

OCEAN SCIENCE AND OFFSHORE ENGINEERING

Volume 5

Submersible Technology

Proceedings of an international conference (SUBTECH '85, 'Designing for Intervention' in association with 7th Underwater Engineering Symposium) organized by the

Society for Underwater Technology and the Association of Offshore Diving Contractors, and held in Aberdeen, UK, 29-30 October 1985

Published by Graham & Trotman Ltd.

Contents

Opening Address George C. Band

Part I Drilling

CHAPTER 1 Evaluation of the last five years of ADS/ROV in drilling

Xl

operations 3 H. B. Hansen and O. C. Andersen

CHAPTER 2 Dual ROV-manned vehicles 7 S. B. Boulton

CHAPTER 3 Designing for intervention drilling-ROY 15 F. R. Frisbie

CHAPTER 4 Dedicated vehicle: A new remotely operated vehicle specifically designed for support of exploration drilling 19 G. Hawkes, S. Earle and S. Etchemendy

Part II Platform Cleaning

CHAPTER 5 Antifouling techniques D. Sell

CHAPTER 6 Slippery paint D. Miller

CHAPTER 7 Water jetting by an ROV _ M. Clegg

CHAPTER 8 Hutton production risers-A novel cleaning problem J. A. G. Tyson

v

29

41

53

59

vi ADVANCES IN UNDERWATER TECHNOLOGY

Part III Commercial Aspects of Underwater Operations

CHAPTER 9 The real-life aspects of managing a lump sum contract M. C. Seeley

CHAPTER 10 Difficult contract clauses B. Moore

CHAPTER 11 Mobilization requirements for DSV s and diving systems J. E. Hendrick

CHAPTER 12 The roles of the client's representative and the diving superintendent M. L. G. Dane

Part IV Survey

CHAPTER 13 Recent and future developments in undersea survey and

71

77

81

85

intervention 97 B. Grandvaux

CHAPTER 14 Intelligent transponder surveying 119 N. C. Kelland

CHAPTER 15 Autonomous vehicles in survey 129 J. R. McFarlane, M. Mullin and E. Jackson

Part V Subsea Production Facilities

CHAPTER 16 Subsea installation and intervention: How to utilise the potential of ROV techniques D. Schouw-Hansen

CHAPTER 17 ROV tooling technology: Montanazo D2 Field ROV

135

intervention system 147 D. Norman and D. Barnes

CHAPTER 18 The underwater shuttle 157 G. G. Santi

CHAPTER 19 A one-atmosphere transfer system for deep-water production support 165 E. Sj~holm

CONTENTS VI!

CHAPTER 20 A swage pile connection technique 175 J. M. Lowes

Part VI NDT

CHAPTER 21 NDE-Overview and legal requirements 183 H. Nordb~

CHAPTER 22 Improving subsea MPI consistency 189 K. P. Allen and A. W. Crawford

CHAPTER 23 ROV inspection system (ROVIS) 199 D. J. Brooker

CHAPTER 24 Electromagnetic inspection underwater 209 S. Hale

Part VII Problems and Requirements

CHAPTER 25 Marine recovery of a hyperbaric rescue vehicle 219 M. N. Young

CHAPTER 26 The design and development of a new class of self-propelled hyperbaric lifeboat for diver rescue 227 R. Morgan

CHAPTER 27 Hyperbaric evacuation 237 C. Logan

CHAPTER 28 Qualifications of offshore personnel: LSTs and diving supervisors 247 P. Blewett

CHAPTER 29 Qualifications of offshore personnel: Inspection personnel 253 G. Mills

Part VIII Inspection and Repair-Platforms/Pipelines

CHAPTER 30 The use of cofferdams for welded repairs to offshore structures 263 G. Harris

CHAPTER 31 Oil company view of future operations-Inspection and repair of deepwater structures 271 N. Eikas

CHAPTER 32 Automatic stud welder for surface and underwater applications 283 C. Smith

viii ADVANCES IN UNDERWATER TECHNOLOGY

CHAPTER 33 Grouted clamps for platform repair I. E. Tebbett

CHAPTER 34 Use of concrete mattresses K. E. J. Miller

CHAPTER 35 Trenching and burial of submarine pipelines A. C. Palmer

CHAPTER 36 Pipeline inspection by ROV N. F. Braathen and A. J. Sandford

CHAPTER 37 Seahorse II J. Haas

Part IX Vehicle Development

CHAPTER 38 Beyond +2000 Feet M. St. E. Cardew

CHAPTER 39 Designing reliability into systems H. R. Talkington

CHAPTER 40 The low-cost remotely operated vehicle (LCROV) D. Walsh

Part X Non-Oil Related Engineering

289

297

305

313

319

333

337

343

CHAPTER 41 Environmental monitoring through the use of ROVs 355 R. L. Allwood

CHAPTER 42 Power cable repair underwater 361 A. Homer

CHAPTER 43 Oceanographic tasks and tools-A survey of some recent developments 367 J. S. M. Rusby

Part XI The Cost Effectiveness of Underwater Operations

CHAP.TER 44 Statistical analysis of the time taken for various underwater tasks 385 G. W. Chew

CONTENTS ix

CHAPTER 45 Potential improvements in the efficiency of underwater operations 393 S. Parfitt

CHAPTER 46 Are ROV s efficient? 399 J. D. Smith

CHAPTER 4 7 DAVID: A versatile multipurpose submersible support system for remote control or diver-assisted performance 407 G. E. Marsland and K. Wiemer

The following papers presented at the conference were unfortunately not available for publication:

Competition, N. Chambers Case history of a major structural repair underwater, W. J. F. Thomas The incidence of decompression sickness in the deep air diving range, T. Shields

Opening Address-SUBTECH '85 George Band, Director-General, UK Offshore Operators Association

Ladies and Gentlemen,

I am honoured to be asked to make the open­ing address atSUBTECH '85 in these splen­did new and permanent Aberdeen Con­ference facilities which were inaugurated only last month at the opening of Offshore Europe '85 by the Prime Minister. I was particularly pleased to be able to say on that occasion that, by her presence, she was recognizing the importance of the offshore industry to the United Kingdom as a whole.

Earlier in the year at the Houston Offshore Technology Con:ference, I noted that half the technical papers were devoted to activities in the North Sea, and that the top award for Technology was made to Conoco for its development of the Tension Leg Platform in the Hutton field. The North Sea is where many of the most exciting developments are still taking place these days.

The theme of this conference is 'Designing for Intervention'. At a time when con­ferences seem to be proliferating faster than field developments, it is good to see the

Xl

rationalization brought about by the merger of the Association of Offshore Diving Con­tractors' (AODC) 7th Underwater Enginee1"­ing Symposium and the Society for Under­water Technology's SUBTECH. These organizations are to be congratulated in pro­ducing a complementary and balanced pro­gramme. I hope this marks the start of a trend toward fewer but more topically directed events.

It is essential that these gatherings, like your conference planning committee, attract a good mix from both contractor and client companies. In the informal and hopefully friendly atmosphere that they generate there is an opportunity to make fresh con­tacts, improve communications and create a better understanding of each other's prob­lems. These problems can be particularly sensitive in the area of commercial arrange­ments where the client seeks to procure work at an attractive price and the contractor seeks to win competitive tenders, carry them out and remain successfully in business with­out verging on bankruptcy in the process. I

Xli

am therefore particularly looking forward to chairing the session this afternoon on Commercial Aspects of Underwater Opera­tions.

On the technical side, the conference sets out to address a range of underwater inter­vention techniques were the industry is becoming more and more sophisticated. Even so, we must not become complacent about safety standards. There is a school of thought which places more emphasis on deep water operations than those in shallow water. The AODC does not subscribe to that. We must recognize that a diving operation in 20 m of water can be just as hazard­ous-sometimes more so-than in 200 m.

The total volume of activity in the offshore sector inevitably results in the majority of the conference papers being devoted to that sector. Nevertheless, I hope that those dele­gates concerned with non-oil applications will find much to interest them. There is considerable potential for newer inter­vention techniques, particularly of remote operating vehicles (ROVs), to be applied to the civil engineering, onshore and scientific sectors.

In this address, I will not try to compete "vith the technical expertise oflater speakers but you may appreciate a general survey of the UK offshore scene (Fig. 1). On its 21st birthday this year, this young endeavour has come of age, cited by the Prime Minister from this lectern as 'one of the outstanding British industrial achievements of the 20th century'.

Within a few y~ars of the first licences being granted in 1964, gas discoveries enabled the nation to become largely self­sufficient. The first oil was brought ashore on 17 June, just a decade ago, and within five years we had attained net self-sufficiency \vith production around H million bid. Today at 2! million bid there is a net 1 million bid available for export contributing £7 billion to our nation's balance of payments. This development has required an increasing stream of expenditure which astonishingly now accounts for about one-quarter of all UK industrial investment (Fig. 2).

ADVANCES IN UNDERWATER TECHNOLOGY

NORTH SEA ­MAIN FIELDS

""""LO ~ GAS FIELD c:::> O .. PlPfU E:

GASPIPEUN!E

IHTERNJJJONAJ.. eOUNOAfty

THISTLE

DUNlIN

MAGNUS

MURCHISON STATFJORD BRE NT

_ HUTTON I NIN IAN

ULLOM " ~ALWYN VOE / i

, I

,' SRUCE n " I.,'7;RIGG

" ,,'I-,L.BEAYl , , ' , , i , , , , , , I ' ~ PI P EA

SLEIPNER BRAE MILLER

CYRUS \ MAUREEN

=-.-1111'---''T'"fORTIF.S _L_- , • MONTROSE

W. SOLE

\ ,.. UlA \. EKO FI SK

, . I

__ ~ VIKING \.

-------- ~ ~

,'. ~ ~ .. I

HEWETT ~INDEfAT IGABLE (Jc-\ \ 1.'1 .

BA CTON -' LEMAN; . Fig. 1 UK offshore development (source: BP).

As the government acted in the late 1970s to obtain a higher proportion of the total revenue through increases in the Petroleum Revenue Tax, there was a hesitation in the rate of progress, and in two years (1980-81), only two oil developments were started, Alwyn and Clyde (Fig. 3). Today, four years later, the construction industry is still suffering from this hiatus. Fortunately, representations from all quar­ters of the industry led to a better under­standing and rapport with Government so that crucial changes in the 1983 Budget, to­gether with increased gas prices now being offered, somewhat hasitantly, by British Gas are leading to a resurgence of both oil and gas activity.

The level of exploration and appraisal activity-a useful barometer of activ-

16

~

12

o :3 8

a:; ...

4

SO

UR

CE

: CE

NT

RA

L S

TA

TIS

TIC

AL

OF

FIC

E

o . ..

.----

--.. --~

.....

---i

~,/"

/ 19

55

1960

19

65

1970

19

75

1980

o O

IL A

ND

GA

S D

EV

EL

OP

ME

NT

0

MA

NU

FA

CT

UR

ING

AN

D O

iliE

R E

NE

RG

Y

-O

IL A

ND

GA

S D

EV

EL

OP

ME

NT

AL

ON

E

Fig

. 2

UK

ind

ustr

ial

inve

stm

ent

(sou

rce:

She

ll U

K)

o 'i:I

to] Z

0-<

Z o ::c­ O

t:I ~

to]

UJ

UJ ~:

Vl

Ul

Z

Z o I­ w.. o Vl

sex)

4(X)

Z

:lex)

o :J

....I ~ I

Vl

Ul >

0::

Ul

Vl ~2()

()

Ul

....I co « 0:

: U

l > o u U

l 0:

: J(

X) o

'Au

k

*Bre

nt

Arg

yll

For

ties

Ber

yl A

Pip

er

1972

19

73

II

Hea

ther

Mon

tros

e

'"So

uth

Co

rmo

ran

t

* Dun

lin

Cla

ymor

e

Thi

stle

Sta

tfjo

rd

(UK

)

Nin

ian

1974

19

75

Fig

. 3

Bu

chan

Mau

reen

I 'M'oo

'N

ort

h

NW

C

orm

ora

nt

Hut

ton

Bea

tric

e

, l1

utan

B

rae

r:m N

OT

PR

OD

UC

ING

BY

EN

D 1

9114

~':'

:"""

""""

""':

" :.:.

: .......

;.:.: ...

:::::::,

Nor

th B

rae

Bal

mo

ral

Hig

hlan

der

Dun

can

-.,.,-.-

.-D

e-ve

ron

Inne

~

4 :l~ 8 <

rn

;>:l » CO

r rn ;>:l rn Vl rn ;>:l <

2 Bl I ~

r r (5 z Vl o ."

CO » ;>

:l

I~

G;

}""";~"

I' ·'"'m

., !':

:::C

1 Yd

e ::::

:::.

---l I

I

I I

f!!ii!~;~:

:iii!!!

":Jt:: Ber

yl B

iJli

J!!!i!!!J

~:

(:::

::}?

J!

Cyr

us

I L (

)

1976

19

77

1978

19

79

1911

0 19

111

1911

2 19

113

19H

4

YE

AR

IN

WH

ICH

DE

VE

LO

PM

EN

T C

OM

ME

NC

ED

'O

pera

ted

by S

hell

Exp

ro

Dev

elop

men

t: t

he

key

deci

sion

(so

urce

: S

hell

UK

).

:.< <' :>

t:::J

<:

:> z n M

w

.....

Z

c::::

Z

t:::J

M

~ ~ >-3

M ~

>-3

M

n ::z:: z o t-< o Q

...q

OPENING ADDRESS xv

180,-----------------------------------------------, 1eo 170 1eo 1S0 140 130 120 110 100 80 eo 70 eo so 40 30 20 10

18e4 18e6 18ee 1870 1872 1874 187e 1878 1880 1882 1884

ISS! EXPLORATION I?iZI APPRAISAL

Fig. 4 UK offshore exploration and appraisal wells drilled.

ity-shot up to record heights in both 1983 and 1984, with 128 and 182 wells respectively (Fig. 4). Initially, from discussions with our 40 Operators, I thought that this year might even exceed 1984. However, the need for one or two of our members to strengthen their financial defences against the depredations of Mr T. Boone Pickens or to pay for rather expensive mergers-neither of which have discovered a single barrel of additional hydrocarbons-plus the current softening of oil prices, have required some companies to trim their programmes. Even so, I still expect 1985 to match the level of 1983. Equally important, the level of exploration success in the UK Continental Shelf remains consistently high over the years, reported by the Dept. of Energy in 1984 as 1 well in 4.6, or 22%.

A year ago, the UK Offshore Operators Association (UKOOA) produced a more than usually detailed look at the future, based on the aggregated reserves and expected pro­duction profiles of all its members. Entitled 'Potential Oil and Gas production from the UK Offshore to the Year 2000', many of you will be familiar with its conclusions:

- That there was a good chance for the UK still to be producing close to self-

LIQUIDS PHOD.· ASSUMED RATE OF DEVELOPMENT K DPD NEW OIL FIELDS: 3000 NEW GAS FIELDS:

3 PLATFORMS/YR. 4 PLATFORMS/YR. I PLATFORM/YR. NEW GAS, CONDENSATE FIELDS:

2500..----...

2000

NEW CONDENSATE 1500

1000 COMMITIED

NEW OIL FIELDS 500

1984 1986 1988 1990 1992 1994 1996 1998 2000 YEAR

Fig.5 Potential liquids production from UKCS North Sea developments

GAS PHOD •• MM FT3/DAY

5000

4000

3000

2000

1000

ASSUMED RATE OF DEVELOPMENT NEW OIL FIELDS: 3 PLATFORMS./ YR. NEW GAS FIELDS: 4 PLATFORMS / YR. NEW GAS· CONDENSATE FIELDS: I PLATFORMS / YR.

OTHER COMMITTED

NEW GAS CONDENSATE

FIELDS

NEW GAS FIELDS

NEW ASSOC.

1984 1986 1908 1990 1992 1994 1996 1998 2000 YEAR

Fig. 6 Potential gas production from UKCS.

Dev

elop

m.e

nt fo

rcas

ts

1.98

.5

1.98

6 1.

987

1.98

8 1.

98.9

1.

9.90

1.9

.91

1.9.

92

1.9.

93

Tot

al n

ew d

evel

opm

ents

co

min

g on

str

eam

4

1 7

8 6

4 7

7 7

Mob

ile r

ig y

ears

35

37

39

.5

33.5

30

32

32

35

35

M

iles

of p

ipel

ine

buil

t 10

0 10

0 10

0 50

50

50

80

50

80

N

o. o

f off

shor

e pe

rson

nel

28,0

00

28,0

00

30,0

00

30,0

00

31,0

00

33,0

00

36,0

00

37,0

00

38,0

00

Fig

. 7

Sco

ttis

h D

evel

opm

ent

Ag

ency

-dev

elo

pm

ent

fore

cast

s.

1.

Div

ing

equi

pmen

t 3,

779

3,80

8 4,

481

5,15

7 5,

655

5,98

0 6,

483

7,04

1 7,

688

2.

Div

ing

serv

ices

, di

ving

sup

port

ve

ssel

s 75

,634

76

,203

89

,650

10

3,14

5 11

3,07

0 11

9,55

7 12

9,62

0 14

0,76

7 15

3,69

3 3.

D

ivin

g in

spec

tion

/ mai

nten

ance

15

,080

15

,208

18

,114

20

,970

23

,144

24

,483

26

,444

28

,771

31

,499

Tot

al

94,4

93

95,2

19

112,

245

129,

272

141,

869

150,

020

162,

547

176,

579

192,

880

Fig

. 8

Sco

ttis

h D

evel

opm

ent

Ag

ency

-div

ing

/un

der

wat

er s

ervi

ces.

1.9.

94 6 33

40

41,0

00

8,18

6

163,

618

33,6

73

205,

477

1.9.9.

5 6 33

40

43,0

00

8,62

6

172,

417

35,4

71

216,

514

~

~. >

t:J

-<: > z o tIj r.n

...... z e z t:J

tIj ~ ~ tIj ~

>-3

tIj o ::q

Z o l'

o Q

>-<

OPENING ADDRESS

sufficiency in both oil and gas as we enter the 21st century. The hypothetical but very reasonable forecasts generated from an assumed pace of development of 3 oil, 4 gas and 1 condensate field per year are shown in Fig. 5 for oil plus condensate and Fig. 6 for gas.

-Also, given reasonable economic con­ditions, we predicted there could be a fresh wave of opportunity for those British­based contractors and equipment sup­pliers ready to go out and compete to win the highest possible proportion of the £60 million (in 1984 money) that will need to be spent by the operators and co-licensees on future exploration, new field develop­ment, operating and maintenance costs over the next 15 years.

More recent studies, for example by the Grampian Regional Council and by the Scottish Development Agency, are reinforcing these conclusions. The former's development forecasts for the next decade (Fig. 7) have been fed into a model developed for the latter to give operators' expenditure forecasts in the same 77 categories of products and ser­vices as are currently used by the Offshore Supplies Office in compiling operators' Quarterly Returns. The forecast total of orders placed increases during the period from £3 billion in 1985 to £4 billion in 1990 and then remains at that level. The tabu­lation for Diving and Underwater Services will be of particular interest to this audi­ence (Fig. 8), showing an increase from £88m in 1984 to £94m in 1985, and increas­ing steadily thereafter to over £200m in 1995 (still at 1984 prices). This growth indicates that Diving and

Underwater Services have an increasingly important part to play in future field developments which seem to be moving in three directions while making the maximum use of the existing infrastructure already in place.

First, the conventional fixed platform is being streamlined, with lighter topsides and, when drilling is finished, possibly even

Notional Development Only. Not in First Phose.

KITTIWAKE

xvii

GANNET FACILITIES

SCHEMATIC DIAGRAM

- Gas lines •• _ •• Oil lines

11111111111, Injection water

'.... Gas lif! • ••• , •• Glycol

D._,ngNo,U·18J99181W1

Fig. 9 Gmmet Cluster Field Layout (source: Shell UK).

unmanned like the planned ShelljEsso Eider project, or in a cluster of smaller accumu­lations like Gannet (Fig. 9).

Secondly, the floating production system like the pioneering Argyll, Buchan, and Balmoral or the revolutionary Hutton TLP (Fig. 10).

Thirdly, the totally underwater concept: the Cormorant UMC (Fig. 11), the Highlander project or the recently approved Scapa, all of them so far needing to be tied in to a rela­tively nearby platform.

Last month at Offshore Europe and again at this conference, we are able to hear and learn about the latest technical develop­ments and innovations which will enable the oil and gas fields of the future to be developed

xviii ADVANCES IN UNDERWATER TECHNOLOGY

Fig. 10 The Hutton Field Tension Leg Platform (source: CONOCO (UK) Ltd.).

profitably in smaller and increasingly com­plex accumulations and, if they can be found, in deeper waters and in the new frontier areas opened in the ninth and subsequent rounds of licensing. The Government

encouragement for 'Generation of New Technology', as one of the criteria in the Ninth Round Licensing applications, has revealed that the current total of on-going Research, Development and Demonstration

OPENING ADDRESS

MUL TI- PURPOSE SERVICE VESSEL

(MSV)

UNDERWATER MANIFOLD

CENTRE (UMC)

SATELLITE WELL CHRISTMAS TREES .~~

REMOTE MAINTENANCE

SYSTEM (RMS)

P1 SATELLITE WELL

xix

Fig. 11 South Cormorant Underwater Production System (source: Shell UK).

projects of the upstream oil and gas industry in the UK already amounts to some £140 million.

As the Prime Minister said to us last month: 'We have a fantastic story to tell: Britain today is at the very forefront of technological development and, in some cases, ahead of the rest of the world'.

Let us all here today accept the goal to make the UK the premier centre of deep water offshore technology in the world.

Thank you for the attention, and may I wish you a stimulating and successful con­ference.