bluuebunny/crossref_metadata_2025_split huggingface dataset:
Jacket Launch by Self-Propelled Launch Vessel: A Cost-Effective Method
Authors: Leenaars Cees E.J. 
Published: October 2008

ABSTRACT
During the month of March 1994 the first ever direct jacket launch from a self-propelled semi-submersible heavy-lift vessel was successfully completed.
The successful launch at Bombay High followed direct on the load-out and transportation of jacket and piles from Korea.
Shown is that jacket fabrication in low wage areas can result in substantial cost savings when using the advantages of transportation by a self-propelled launch - vessel.
The special characteristics of a self-propelled launch vessel are discussed.
Limits for the maximum jacket size are given based on the details of the conversion from heavy-lift vessel to launch vessel.
A short report of the actual launch operation at Bombay High is given.

INTRODUCTION
Traditionally the concept of transportation and launch by a tug and barge combination has restricted the range of suitable construction sites because of the required short transportation distances.
The longer the sailing distance for a tug and launch barge combination the more negative the exposure for the project, i.e.:High transportation costs as a result of potential high mobilisation time of the required launch barge;Long transportation time due to relative slow speed and weather sensitivity resulting inschedule uncertaintyHigher risks relating to damage and/or total loss during transportation, which results in higher costs for Marine Cargo Insurance coverage.
The introduction of a self-propelled launch unit opens up a large range of world-wide construction locations, eliminates the above mentioned negative exposures related to longer distances and offers arange of low wage construction areas.

FABRICATION COST SAVINGS
Fabrication cost savings can be obtained when a jacket is fabricated in a low wage area. In Figure 1 is indicated how much can be saved on building a jacket for West Africa in alternativeconstruction areas compared to fabrication in Northern Europe.
(Available In Full Paper)
Shown is that building in Vietnam - Philippines - China region can lead to savings over US$ 15 million.
As the situation on the international market changes continuously, possible savings have to be investigated for each project individually.
Traditionally the mobilisation from low wage areas by tug/barge combinations was thought not to be attractive due to the long distance.
The problems of mobilisation over a long distance by tug/barge areHigh risk; due to less control of the barge by the tow wire,Long transportation time;due to low speed of the barge/tug combination,High accelerations;resulting in extra steel weight of the jacket and the sea fastenings,High insurance costs; as a result of the above disadvantages.
These disadvantages can be avoided by transportation on a self-propelled launch vessel.

CHARACTERISTICS OF A SELF-PROPELLED LAUNCH VESSEL
By using a self-propelled launch vessel above mentioned problems can be captured.
Design, Fabrication, and Integration Testing of the Garden Banks 388 Subsea Production Template
Authors: Ledbetter W.R. , Smith D.W. , Pierce D.M. , Padilla J.R. 
Published: October 2008

INTRODUCTION

Project Profile
Enserch Exploration's Garden Banks 388 development has a production scheme based around a floating drilling and production facility and subsea drilling! production template. The Floating Production Facility (FPF) is a converted semisubmersible drilling rig that will drill and produce through a 24-well slot subsea template. This development is located in Block 388 of the Garden Banks area in the Gulf of Mexico approximately 200 miles southwest of New Orleans, Louisiana. The production system is beinginstalled in an area of known oil and gas reserves and will produce to a shallow water platform 54 miles away at Eugene Island 315.
The FPF will be permanently moored above the template. The subsea template has been installed in 2190 feet of water and will produce through a 2,000 foot free-standing production riser system to the FPF. The produced fluids are partially separated on the FPF before oil and gas are pumped through the template to export gathering lines that are connected to the shallow water facility. The system designed through-put is 40,000 BOPD of oil and 120 MMSCFD of gas.

Template Snapshot
The template's function is to provide a controlled drilling pattern for subsea wells and serve as a conduit to produce oil and gas to the FPF. The template has "slots" to accommodate 24 wells and provision to receive oil and/or gas production through two 12-inch pipelines from an adjacent field. The well slots on the template exterior rows can be either drilled and completed through the template structure or can tie in two 4-inch flowlines from satellite completions. The interior well slots can only be completed as template wells.
The primary structure of the GB-388 template is an all steel welded space frame fabricated from wide flange, rolled tubular sections, and flat plate. The structure is 167 feet long, 86 feet wide, and 20 feet high over the area covered by the 24 well slots. The elevation rises to 30 feet at the riser base end of the template. The structure is secured to the sea floor by eight 42 inch diameter piles.
A stiffened steel plate mudmat covers the base of the template, except the 24 well guides and the eight pile sleeves. The mudmat supported the 1,260 ton weight (lift weight) until the piles were driven. The template was leveled and locked into the piles by plastically deforming a section of each pile into premachined grooves in each of the 8 pile sleeves. The four piles in the wellbay area are 395 feet long and penetrate into the soil 350 feet. The four piles positioned around the base of the free-standing production riser are 305 feet long, with a penetration of 250 feet.
The template structure is protected from corrosion by a high quality, two coat epoxy paint system backed up with Galvalum III type (aluminum alloy) cathodic protection anodes.
The functional requirements for the GB-388 template include providing adequate space and structural support for drilling and completing up to 19 template wells.
Deep Water Installation - Heavy Mooring and Riser Systems
Authors: Alvheim N. 
Published: October 2008

While the move into deep water has provided exciting challenges often resulting in ingenious and novel equipment it is usually the equipment or the solution itself that is remembered and discussed.
Too often we over look just bow that novel equipment Was actually installed.
Perhaps one of the most exciting and ingenious equipment designs of recent times is the Submerged Turret Loading (STL) system. To date we have had the privilege of installing each of the 3 systems so far produced. Our work is well on course for installing the fourth during the coming summer.
This paper addresses the installation of two of these systems in the summer of 94 in 350m of the hostile Halten 13ankwaters as part of the Conoco Heidrun development. (Slide)
Because the Norwegian oil industry has always been atthe cutting edge of technology each new development results in the usual plethora of statistics which when presented in papers like this area companied with a long list of superlatives like tallest, heaviest deepest, quickest etc.etc. Installation work at Heidrun has a similar list.
Because the 2 STL systems at Heidrun (called Direct Shuttle Landing DSL) were to be installed in such deep water the sheer size of the system components are worthy of review.
Each DSL (see fig. 1) system is composed of the following individual components:One 130 T submerged turret buoy. Once installed the submerged turret buoy floats 50-60m below the surface.One 16" flexible riser.Eight mooring lines. each made up as followsOne 24T fluke anchor.One 120mm studless chain length 600m.One 130mm plastic coated spiral stranded lower segment wire. length 400rn.One 19T mooring line buoyancy elementOne 130mm plastic coated spiral stranded upper segment wire, length 200m.
Fig. 1 (Available In Full Paper)
With the two systems the quantity was of course doubled and therefore both the number and size of the components alone placed considerable constraints on the size and type of installation vessels.
Inconsequence we believe installation could not have been undertaken with the smaller conventional anchor handlers because that would have involved more frequent trips to port or necessitated difficult ship to ship transfers with all the inherent safety risks.
Moreover, several aspects of the system meant that considerable care had to be taken in handling system components,
The first of these being the plastic coated segment wires. Wt the plastic coating would enhance the life of the mooring this meant that the wires were to be handled at all times in such a manner that did not damage the coating.
Additionally the sheer size of the forces that would be encountered as the final connections were made to these wires produced an installation design that required very large items of equipment to be attached to the side of the installation vessel.
With apparently no other constraints it was intended to complete the most of the installation using the MSV Maxita, one of the largest offshore construction support vessels of its type.
Lease Based Production Services
Authors: Gisvold Kaare M. 
Published: October 2008

ABSTRACT
Built in 1986, the PETROJARL 1 production vessel finished its 7th consecutive contract on January 26,1995 after having produced 17.9 mill barrels of oil from the UK Hudson field for Amerada Hess UK.
Table 1 summarizes the main data relating to the 7 historic Petrojarl contracts, A total of 188 MMBBLS of oil has passed through the vessel in these 8 years, while working for 7 different operators. Max.water depth hasbeen 330 m (TROLL) and minimum 71 m. (ANGUS). Max. production has been 41,200 BOPD from HUDSON, while max throughput has been 310,000 BOPD acting as a FSO on FULMAR. Contractual regularity has been in excess of 98 'A, proving that a floater can deliver as well as the best gravity platforms even under North Sea conditions.
Throughout, the vessel, and the associatedshuttling services have been owned and operated by Golar-Nor Offshore AS, acting as a production contractor. Regularity and safety records have been remarkable, andwhat was perceived as exotic and unproven technology is today state-of-the art. The advantages of production contracting have become clear to the industry, and this new contracting niche is now poised for rapidgrowth in the years to come.
A result of this experience is that the Petrojarl 1 has now been contracted to ARCO British to produce their 24 MMBBLS BLENHEIM field over an expected period of 4 years.
A further result is the newbuilding project "Petrojarl 4", currently under construction to meet First Oil in early 1996 from the Foinaven field West of Shetland for BP, in 500 m of water. The contracts are novel intheir format and are further described below.
This paper examines the contract history that has led up to this situation and discusses the way ahead.

PETROJARL 1 employment history

General
The PETROJARL 1 (see Table 2 and Fig, 1) was conceived in 1983, and after extensive technical detail work and thorough market studies, ordered in mid-1984 from NKK in Japan. On ordering the vessel, it was uncontracted, although several companies had expressed interest in using such a vessel, were it only available. In effect, the PETROJARL 1 has created its own market, In retrospect, the timing was perfect. 1984 was a year when oil prices were soaring towards the $30 mark, and finance institutions were bullish and active for new business. All this changed dramatically before the vessel was delivered in May 1986. The world has not looked the same again.

OSEBERG
The vessel secured its first contract for long term testing of the OSEBERG field in Norway, for operator Norsk Hydro late in 1985, after a lengthy negotiation which focused mainly on technology aspects, At that time, the OSEBERG field had already been declared commercial and the purpose of the test was optimisation of well layout, perforation depths and depletion strategy. As a result of the test, some wells were saved, and recovery was increased by approx, 5 mill BBLS. In gross terms, this test alone paid for the vessel, although the greatest beneficiary was the Norwegian government.
The Norne Production Ship - Topside Design and Construction Strategy
Authors: Solberg L. , Urdahl P. 
Published: October 2008

ABSTRACT
Development of the Norne field at 380 m of water depth was dependent of a floating structure with the production capacity to meet the need of 27500 Sm3/SDA Y(770,000bLS/day), and a storage capacity of 115,000 m3. This challenge was met by the selection of the Tentech 850 monohull design and the development of a topside design that meets these requirements. The critical element in selection of the chosen concept, was the solution for the turret and swivel area. Particularly the swivel concept is at the borderline of proven technology so far in the industry, and need special attention during he development phases in 1995-1996. The contracting philosophy in the development of the production ship was to make use of the industries know how in the most efficient way, and design and procure the topside based on a system approach. Thus benefit from utilizing the best know- how and experience in the industry. This paper describes how this is done based on functional specifications, and with a design and layout of the topside to make this system approach possible.

INTRODUCTION
Total reservoir reserve for the Norne field is estimated at 160 mill. Sm3 of oil and 29 mrd. Sm3 of gas.
The reservoir driving mechanism will be a combination of water and gas injection. Produced gas will be reinjected into the gas cap and water will be injected into the water zone.
The topside design has to meet the following Design capacity:
(Available In Full Paper)
After the evaluation of several concepts in the summer of 1993, Statoil and the partners decided that the production and storage monohull vessel combined with a subsea installation was the best technical and economical solution for the development of the field, In the autumn of 1993 the further development of a solution for the vessel in combination with the layout and the main process philosophy for the deck arrangementcontinued in order to chose the best conceptual design for the vessel. The contracting strategy was to chose a concept for the ship in order to develop the building specificationstogether with an engineering contractor to obtain a lump sum contract for the ship during autumn 1994. The emphasis was further to select a topside engineeringcontractor in spring 1994 in order to develop the design for the topside based on functional specifications and place the orders for the main system packages duringautumn 1994 (Fig. 1- Schedule).

TOPSIDE DESIGN

General Layout
The monohull production vessel has some particular advantages compared to other floaters with integrated topsides.
During the operation, weather vaneing around the turret will provide that the ship is headed against the wind and waves at all times. This reduces the movements of the ship, thus minimizing tilting problems in the process equipment. Furthermore, positioning the ship so that the prevailing wind is slightly from the port side forces the exhaust gases to drift quickly to the side of the platform rather than along the process deck.
EURIPIDES, Load Tests on Large Driven Piles in Dense Silica Sands
Authors: Zuidberg H.M. , Vergobbi P. 
Published: October 2008

Abstract
In 1995 an extensive load testing program was conducted on 30' pipe piles in dense silica sands similar to those found in the southern North Sea. A highly instrumented pile was driven at one location, extracted and redriven at a second location. A total of twelve static compression and tension load tests were performed at three penetration depths between 30 and 47 meters.
Test objectives included acquiring reliable data on capacity of offshore type piles in sands which hitherto were hardly available and to understand the failure mechanisms in order to improve current foundation design.
The paper describes the design of the testing programme and project organisation and funding. Details of the lest pile and instrumentation to measure the loads in the pile and the pile-sand interaction are highlighted with an emphasis on quality of the measurements. The field-work and innovative testing facilities are also described.

Introduction
Estimates of axial capacity of open-ended pipe piles in sand are an area of great uncertainty. Various authors (e.g. Pelletier et al., 1993) have argued that the world-wide used API recommended practice (RP2A, 1982-1991) does not properly account for fundamental parameters (pile length, plug behaviour, horizontal stresses, driving history, etc.) and underestimates the capacity of driven piles in very dense sands. On the other hand no other widely recognised design method is currently available.
The base for a design method should be an understanding of the pile-sand load transfer in parallel with representative full scale pile load tests to confirm this (Hobbs, 1992). Some new promising design methods have been published in recent years (Randolph et nf., 1992, Lehane et al., 1992), but the existing data base on pile tests in sand is limited to piles of relatively small size and/or low capacity. Moreover few tests provide instrumented data of enough quality and resolution to confirm the load transfer in detail.
While this unsatisfactory situation has been recognised by most parties involved in foundation design it appeared very difficult to resolve because high capacity pile tests in sand are relatively costly. In 1985 Heerema and Fugro developed a plan to test three 42' piles in very dense sands nearshore Eemshaven in The Netherlands (Fig. 1). On each pile compression and tension tests were foreseen at four penetration depths with a potential ultimate compression load of 90 MegaNewton (MN). The programme costs were estimated at US$ 12 million. Even though a 40% European subsidy was available not enough support from industry could be generated. This contrasts with the fact that about US$ 50 million is spent annually on pile foundations in the southern North Sea and a 30% increase in allowable load could lead to a saving of about US$ 60,000 per pile installed (van Zandwijk, 1986).
Marine Dredging for Gold, Offshore Alaska
Authors: Gamett R.T. 
Published: October 2008

Abstract
Following the discovery of gold in 1900 on the beaches of Nome, a major offshore extension was partially drilled in 1963 and 1972. To mine the marine deposit, WestGold purchased second-hand the world's largest, ocean-going, bucket-ladder dredge, the ‘Bima’. Designed for original use on a very different tin deposit in Indonesian waters, the dredge arrived in Nome in 1986. With an overall length of 140m and &gt;7,000 hp installed, it could dig to 45m depth at a rate of 2,000 m3/hr. Ttreoffshore conditions in Alaska, however, were entirely different from those where the dredge had operated previously. The highest gold grades were in the uppermost 2m, and the sediments were much coarser and very resistant (o digging. The marine conditions were considerably more onerous and the wind/wave conditions grossly exceeded design specifications. Sea ice limited operations to the months June through November, reducing the availability to an average of about 70%. The throughput rate averaged 457 mshour over 4 years. Very high operating costs necessitated an elevated cutoff grade and much more drilling than originally anticipated in order to define a dredge course, Altogether, 1I8,078 oz. of gold were recovered from 1987 to 1990, inclusive, when the operation was stopped because of the low gold price and structural failure. The experience illustrates the need to match marine mining equipment to each unique deposit and to delineate the reserves ahead of mining start-up.

Introduction
Gold was discovered in 1900 on the beach of Nome, Alaska, and in the adjacent shallow water of the Bering Seal. Onshore, the Alaska Gold Company has, until recently, continued to employ two bucket ladder dredges, each of 225 liter (9 ft3)bucket capacity on placer gold production. The company has successfully worked ground similar to that existing offshore but in which the permafrost has been thoroughly thawed in preparation.
Offshore, small scale dredging for gold has been attempted in vain several times this century, Only one company, however, Western Gold Exploration and Mining Company, Limited Partnership (WestGold) has been successful in achieving a significant production. The Nome bucket-ladder dredging operation from 1986 to 1990, inclusive, constituted a unique marine mining experience in the EEZ of the U.S.A.
Six offshore leases were acquired by WestGold from Power Resources Corporation. Extending from the coastline to the 3- mile (4.8km) offshore limit, the total lease area of 8,722 ha already had been partially explored over one third of its extent. Following some geophysical work, sampling had been undertaken with a Becker AP- 1000 hammer drill: in 1963 by Shell Oil Company and in 1972 by Asarco.