TR Consulting

                                     Double-click on pictures to enlarge.

 

 

Start

Company

Products

Services

News 

Download

 

MODULE AND CASSETTE INSTALLATIONS, GENERAL .

What is a cassette ?   Installation in the cellar deck   Outside platform   On top of cellar deck   Piggy-back 

Between modules    Bookshelf cassettes   Under the Platform  Previous page

Cassettes

You will find more details and pictures by clicking the text above.

Since the PEF installation method grant full and minute control during installation, the modules should preferably be designed as cassettes. This means that the module is designed with well defined interface areas to the platform in order to reduce offshore hook up time, hot work and labor cost. 

It is wise to design, fabricate and test out all systems on-shore before installation. Even if the module or systems are planned to have a lay-out over more than one module, this principle may be efficient and cost saving.  Also, in cases where the module is to bulky, has to little strength, or for other reasons will have to be installed in sections, the idea of making cassettes should always be investigated. 

The most typical cassette is a gas turbine driven gas compression cassette or water injection cassette. Some of the platform types designed by TRC is in fact based on the cassette principle altogether.

Advantages:

Fully tested and commissioned systems onshore
Easy installation by the use of defined interface areas
Reduced cost as offshore work is moved onshore.
Reduced cost of installation by using the PEF method
Installation possible under, inside, outside or on the weather deck of the platform.
Easy de-commissioning
Onshore maintenance and re-building made easy.
Shut down normally not required during installation.
Reduced hot work
Reduced offshore crew

Go to top

 

 

Cellar deck cassettes

You will find more details and pictures by clicking the text above.

In some cases, it may be required that the cassette is installed into an existing cellar deck. 

It is easy to comprehend that this is not an easy task for a floating crane or the platform cranes for that matter.

The PEF method, however, makes this a relatively easy task depending on the circumstances.

With the PEF method, it is possible to lift the cassette directly up and into the cellar deck. A horizontal movement is also possible by skidding or by using additional lifting jacks. 

 

Advantages:

Installs the module where the cranes cannot reach
Easy attachment to the cellar deck 
No bumpers and guides needed

 

 

Go to top

 

Cassettes on the outside of the platform

You will find more details and pictures by clicking the text above.

It is very efficient to install cassettes mounted on the outside of the platform. 

This may be done simply by applying our "bookshelf" principle.

If the platform has got available space on lay-down areas or platforms, cassettes may easily be installed here. 

The principles are well suited for platform extensions like compressor cassettes, water injection cassettes, satellite tie-up units, water treatment cassettes etc.

 

Advantages:

Reduces the need of making changes to the existing platform structure or systems
The cassettes may be top-suspended and simply bolted to the platform bracket.
Short installation time
Reduced hot work
Reduced number of offshore crew
Onshore test and commissioning
Better utilization of the existing platform 

Go to top

 

 

On top of cellar deck

You will find more details and pictures by clicking the text above.

The cassettes may also be installed like any other module on top of the cellar deck. 

On existing platforms, a special rig is then needed in order to move the cassette horizontally from the load transfer position into its final position. 

 

Advantages:

Better utilization of the available area
No bumpers and guides needed
The lift rig may be used as a lay-down area
The cassette may easily be removed later
Reduced cost of installation

 

 

Go to top

 

 

Piggy back installation

You will find more details and pictures by clicking the text above.

The cassettes may also be installed on top of other cassettes or on top of modules. 

This is possible to achieve with the PEF method and a horizontal skid arrangement.

 

Advantages:

Installation and removal of drilling modules
Permits flexible platform lay-out
Makes sequential platform development a reality

 

 

 

Go to top

 

 

 

 

 

 

Cassettes under the platform

You will find more details and pictures by clicking the text above.

No other lifting system may actually perform module installations under the platform. 

There are in fact many cases where this position is both favorable and necessary in order to make use of the available space.

 

Advantages:

Makes the "impossible" easy.
Permits more effective use of the platform space and capacity
May even be performed on a live platform

 

Go to top

 

 

 

 

 

Installing cassettes between existing modules

You will find more details and pictures by clicking the text above.

In some cases, it is necessary to install modules between existing ones. 

The contemporary installation method using floating cranes, requires the use of bumpers and guides. 

This inevitably reduces the available foot print, and makes the installation more expensive. 

The risk of damaging the surroundings, modules, process equipment etc is also a factor to consider.

The PEF method makes it possible to install cassettes very close to existing modules.

 

Advantages:

Better area usage factor
Reduced risk of damages
Shut down normally not needed

 

Go to top

 

 

Bookshelf cassettes

You will find more details and pictures by clicking the text above.

The method is one of the most efficient low cost ways of increasing the capacity of an existing platform. TRC has studied two main scenarios; sequential platform development and platform add-ons. 

For the existing platform, the add-on is made easy simply by loading cassettes to book-shelves fitted to the platform outside. This will off course require some modifications to the existing platform or module structure.

Since you never know for sure what the reservoir contain before it has been emptied, it will reduce project risk and increase profit by designing the platform for a sequential development scenario. 

The investment profile , hence the NPV of the project will be strongly effected by this.

Advantages:

Easy installation with a minimum of disturbances
Makes sequential development a real option
Makes the project more flexible during fabrication and installation
Makes the platform more flexible in terms of capacity increase, change-out, re-vamping, maintenance etc.

Take a look at some of the optimized new platform designs from TRC that take full advantage of this design strategy.

Go to top

 

TR Consulting, Joh. Falkb.gt. 10, 5538 Haugesund, Norway. Tel: +47 52729124, Fax: +47 52724196, C.E.O. Cell phone.  +47 90 616969  e-mail: trcons@online.no or trcons@start.no