What is FSRU?

4 11 2009

FSRU (Floating Storage Regasification Unit) is special floating vessel that stores gas and regasifies the LNG tanker.

FSRU berthing

Studies on FSRU have been developed by many engineering and oil & gas company and some of them have been approved by ABS (American Bureau Standard). Currently several FSRU is under construction and will be operating in the near time. FSRU incorporate many of the same safety features as an LNG carrier and each of the technologies and components involved are tried, tested, and reliable. Floating offshore facilities similar to the FSRU have been employed around the world for more than 25 years and have a proven record of accomplishment of safe operation, with some operating continuously in the most severe weather conditions.

Arun, Bontang, Donggi Senoro and Tangguh are major gas field that have gas wells already drilled and capped. Alternatively, FSRU would be suitable LNG terminal. In fact, several islands in Indonesia need of gas that can almost solely be provided by LNG.

Terminal Cost Comparison

Advantages of a FSRU:

• Lower port management & maintenance

• Replacement for mini LNG Terminal

• Environmentally friendly

• Easier to get approval from local authorities

• Replacing existing “high” emission solutions

• More economic than on-shore solution

• Shorter start-up & construction time

• Particular for conversion solutions

• Bridging solution for smaller volumes

• Flexible, can be relocated, can trade as a vessel

• Can be SRV (shuttle), stationary, moored offshore or dockside

Related articles are:

(CJP-041009)





Crawler crane considerations

5 09 2009

Operating crawler crane

As construction activity in oil industry is increasing in Indonesia, EPCI Company should ensure all lifting operation goes properly. Usually, contractors will use many types of equipment such as sling, shackle, load cell, which are known as lifting accessories or rigging equipment. The other important to do is to check crane regularly prior to main activity. This topic will focus on crawler crane in order to test it safely and properly. As few references are available in the nation, worldwide regulations can be an alternative instead of PP No.70 1996.

Many guidance or directions provide description, method, configuration and sequence of crane load test. Regulation explains many aspects which mandatory for basic crane testing. The following must be counted into consideration:

  1. Work force (Operator, rigger, leader, etc.) requirements
  2. Lifting equipments
  3. Relevant guidance, recommendation and practice

mammoet-demag-cc-1800-photo

Each data should be defined corresponding appropriate specification. First criterion, for instance, incidental operator must possess a current license (Valid SIO), rigger & supervisor must have competence experiences.

Testing method used must appropriate with crane instruction or operating manual. Load test might use steel plate or concrete block to test the crane for both of static and dynamic testing.

Crane configuration can be carried out used with or without any additional counterweight attached. This should define the configuration in conjunction with load chart, crane capacity, dead/live load, and other relevant factor. Finally, lifting ratio should be more than 1,00 (Load < Actual Capacity). From this moment, Load test should be safely designed.

(CJP-050909)





FPSO

22 08 2009

FPSO (Floating Production Storage and Offloading) is a processing vessel or barge built to meet especially deepwater need. In the latest exploration in deep water development, the requirement to install floating structure is increasing. Fixed structure is almost impossible to be installed in the deep water region.
FPSO is basically a floating tanker with production and processing unit/modules placed on its topdeck. After receiving hydrocarbon from the subsea well, it processing the hydrocarbon into the final product and store them in its own tanker waiting to be pickup by transport vessel or export them with pipeline to shore.

fpso_5422

The main elements of FPSO are:

  1. Hull, the main part of FPSO, this is where FPSO deposit its hydrocarbon. In some of the world FPSO should be double hull.
  2. Topdeck, this is where the modules placed and determined product of the FPSO itself.
  3. Turret, centre of the mooring system of the FPSO and connector production and
    control line to subsea facilities. Turret must be designed in such way that it can
    hold the worst sea condition of where the FPSO operating. The turret design is
    unique that the FPSO can do 360° rotation to do weathervaning.

Turret_6022

Compared to fixed structure, FPSO have economic benefit and reversibility in utilizing such facilities. In many cases it has been the only economic means to an offshore oil field as company explore in remote and deep water with existing infrastructure, and smaller marginal fields are developed in mature areas. Secondly, technology in the area of mooring design and subsea production system has reached an advanced stage where increased feasibility, reliability and unit cost reduction have a favorable impact.
Currently FPSO has become major floating structure produce in offshore production. Not only has it served for deep water (above 500m) it also has become main answer for shallower water. The main advantages of FPSO are:

  1. Short construction and installation schedule especially if second-hand vessel is converted
  2. Can be constructed in low cost-base shipyards
  3. Integral between storage, production and offloading
  4. Relatively insensitive to topside weight
  5. Can operate under various water depth
  6. Low abandonment costs
  7. Safe (ability to disconnect or escape from worst operation condition (eg.cyclone, storm, etc))

There are several articles that you might interest: What is an FPSO?, Flow Near an FPSO Helideck, (FPSO) Vessels.

(CJP-220809)





Lifting Operation

21 07 2009

Installing TopsideThis article endeavours to give sound advice to ensure that all lifting operations are carried out in safe manner. It also addresses types of lift and the safe use of lifting equipment and lifting accessories. The persons involved in the planning and implementation of lifting operations are crane operator, rigger, supervisor, safety person, lifting engineer, company & third party representative. They must have suitable & experience to ensure that a safe system of work is executed. Generally lifting supervisor will be delegated to have overall control of each specific lifting operation. However, for heavy/complicated lifts, he may also act as risk assessment team leader. Contractor team, engineer and supervisor, should participate in the assessment and planning stage of the operation and consultation or discussion of information/ plans with others where necessary. This plan, also known as engineering procedure, is subject to company and third party approval. They should ensure that adequate inspection and maintenance of the lifting equipment has been undertaken and certification is within date. Installing Topside 2According LOLER SI 1998, all lifting operations will be categorized in two conditions: Routine or Non-Routine. The routine lift is the job has been performed before. It is also completed with Job Risk Assessment, The experienced team or crew, and in non-sensitive area. Routine lifting should be categorized into simple or complex lift. The most important thing is that generic lift plans or procedures and risk assessments must be reviewed and amended immediately the risks change from those present when the generic plan was written. For example a change of risk could be new/different equipment used, less experienced personnel being involved, different site hazard, etc.

(CJP-210709)





Marine Spread for Transportation Solution

19 06 2009

Actually, this topic is still interesting. We realize that it’s hard to find marine spread solution especially if we have no relevant experiences regarding this issue. Fortunately, Indonesia have many vendors or brokers that can help us to give what we need with competitive price. www.indonesianship.com is one of the site that offers best and accurate information to the customers with a strong promise of quality services. Yes, we can find a lot of ships, tugs, barges, etc here in Indonesia. But most importantly we should know what we need for our cargo during sea transportation. Finding the correct barge and tug boat is challenge. In fact, we will face with engineering problem and available budget. We can see simple diagram below

FlowchartThis internal flowchart describe the sequence of finding marine spread solution. We, as cargo and client specification have been specified, can define barge, tug and applied load. We should combine it into one engineering calculation sheet. Each sheet has certain calculation model. Barge & tug boat should fulfill its stability criteria and bollard pull requirements.

1Stern tug 'Jul Sofus K' towing Black Marlin into the JacketBelow is a more detailed look at what’s to be considered in choosing a marine spread:

•Overall size of the barge & tug boat capacity

•Barge deck strength check

•Towing method during transportation

•Ocean route and duration

•Valid weather forecast

•etc

After all, we should concern whether available the budget is ok or not before we propose to client within engineering procedure. Just evaluate closely the location of site installation first and maximize marine spread & equipment utilization. We should considerate cost as economical as possible and select the sub-con/vendor whom fulfill their delivery obligation & competitive offers.

(CJP-190609)





Fixed Platform (Part 1)

18 05 2009

Currently, Indonesia have a lot of offshore platforms. Most of them are fixed platform. These main structures can be divided into 3 parts :

  • Jacket

The lower part of main structure will act as covered layer of pile and support upper deck. As you see the image, they may have a lot of braces and other structural support such as can, barge bumper, skirt pile guide and mudmat framing.

Marine Milestones

  • Pile

A Tubular pipe that made of steel will penetrate into seabed through jacket till certain depth below the mudline. Pile consist of main part, stabbing guide, cutoff, transition piece and skirt. 

Piling Proccess

  • Topside/Deck

The upper part of oil platform consist of single or multi module. These module will be supported by main and additional framing through main or cellar or mezanine deck.

 

Upper Deck

Structure installation would be done after load out activity is completed. Installation using lifting method has more benefit than float over method as it will save time and manpower. However additional studies have to conducted before any method can be used to install the module.

(CJP-180509)





The Seafastening

20 04 2009

As we know, this seafastening document will always relate with transportation and offloading documents prior to site fabrication and construction.

Seafastening is activity that fasten the structures such as jackets, decks, modules and other equipments to the deck’s of barge/ vessel. The job can be done either through manual welding, lacing, bolting or by using automation tools. The equipment, consumables, and supervision will be required.

Seafastening by welding

Engineering procedure will be applied in accordance with client and other relevant specification. In fact, minor change of construction plan is only accepted through the reasonable practicable. The document should include the following:

  • Scope of work
  • Arrangment of seafastening & detail drawing
  • Calculation sheet
  • Weather forecast
  • Equipment check list
  • NDE document
  • JSA document

Input data can be obtained through valid weather forecast such as significant wave height, current and wind load. Engineer should make sure that all of these input data are still updated. 

(CJP-200409)