(f Burckhardt éy Compression UNIQUE RECIPROCATING COMPRESSOR SOLUTION FOR OFFSHORE APPLICATIONS PRODUCT DEVELOPMENT, TECHNICAL IMPLEMENTATION AND ITS FIRST INSTALLATION Rainer Duebi Compressors for a Lifetime

2 UNIQUE RECIPROCATING COMPRESSOR SOLUTION FOR OFFSHORE APPLICATIONS Rainer Duebi holds a degree in B.Sc. Mechanical Engineering and a master degree in advanced studies of Business Administration. He started his professional career as Commission-ing Engineer of large onshore gas turbine power stations for ABB and Alstom. In 2003, he joined the Compressor Sizing Department of Burckhardt Compression in Switzerland. As Sizing Engineer and Sizing Manager he conducted projects for LPG marine and LNG BOG onshore and offshore installations. Since 2010 he is Senior Sales Manager and heading a Sales Team....

UNIQUE RECIPROCATING COMPRESSOR SOLUTION FOR OFFSHORE APPLICATIONS 3 Burckhardt Compression has developed a unique reciprocating compressor aimed at a number of applications in the offshore market. The various duties that are specified for these applications need a highly flexible compression solution with variable suction conditions from cryogenic to ambient temperatures. The de-manding installation and operation requirements have been con-sidered in the mechanical design of the compressor and in the compressor package layout. This paper describes the development of the fully balanced Laby®-GI...

4 UNIQUE RECIPROCATING COMPRESSOR SOLUTION FOR OFFSHORE APPLICATIONS CHAPTER 2 and LPG carriers where these systems have been applied over decades.The extreme reduction of mechanical friction in the contactless labyrinth cylinder, results in an extraordinary long lifetime of sealing components. The high-pressure stages four and five employ conventional API 618 lubricated piston ring sealing technology. Six or four cylinders are mounted on top of a vertically arranged crankgear. The double-acting compression stages one to three with labyrinth sealing are typically of the same design as those employed...

UNIQUE RECIPROCATING COMPRESSOR SOLUTION FOR OFFSHORE APPLICATIONS 5 Laby®-GI may therefore be safely included in a machinery room on top of the cargo tank within acceptable structure vibration Limits. 2.3 MODULAR SYSTEM OF THE LABY®-GI COMPRESSOR The layout of the cargo handling equipment and the design of the supporting structure is a task for the navaL architects simiLar to the optimization of the LNG tank deck, where space is considered a premium. The total compressor size is given not only by the compressor itself, but also by the surrounding auxiliary systems such as gas piping, pulsation...

6 UNIQUE RECIPROCATING COMPRESSOR SOLUTION FOR OFFSHORE APPLICATIONS Fig. 5 Package size of LP250 and LP190 5'000 mm/ 197 in. For smaller compressor shaft power applications another smaller compressor frame with reduced stroke was introduced with the advantage of having a reduced plot area but with the same advan-tage as the Laby®-GI LP250 frame. With this smaller compressor LP190 most other applications below the current range of LP250 applications are believed to be covered. Fig. 5 The next chapter will highlight the engineering steps which have been conducted during the design of the Laby®-GI...

UNIQUE RECIPROCATING COMPRESSOR SOLUTION FOR OFFSHORE APPLICATIONS 7 3.1.3 CALCULATION PROCEDURE The calculation for the vibration analyses is carried out in two steps. The first step is the calculation of natural frequencies and mode shapes. This indicates which excitation frequencies will cause resonance effects, and which part of the system will be the most affected. This gives a general overview of the vibration behavior of the system. In step two, Burckhardt Compression per-forms a dynamic response analysis. The excitation comes from the shaking forces, which are a result of the pressure...

8 UNIQUE RECIPROCATING COMPRESSOR SOLUTION FOR OFFSHORE APPLICATIONS (article 3.3). The given design should also withstand sea water atmosphre and additionally shall compensate for unevenness of the structure. A combination of epoxy resin and adjustable supports from VIBRACON® is the recommendation of Burckhardt Compression. Fig. 6 3.6 DESIGN ASSESSMENT FOR TYPE APPROVAL AND CONDUCTED HAZID AND HAZOP STUDIES In the shipping industry, classification societies are non-governmen-tal organizations or groups of professionals, ship surveyors and representatives of offices that promote the safety and...

UNIQUE RECIPROCATING COMPRESSOR SOLUTION FOR OFFSHORE APPLICATIONS 9 Fig. 7 Golar Freeze LNG Carrier, before conversion Table 1 Laby®-GI 4LP250-3A operating data Suction pressure 1.04 to 1.70 bara Suction temperature -140 to -80 °C (transient up to +45 °C) Discharge pressure 45 bara Gas composition Methane (add. Ethane, Propane and Nitrogen) Rotational speed 445 rpm Rated Motor Power 1'300 kW Order date 4LP250-3A March 2008 Mechanical test run June 2009 (Compressor only at work shop Winterthur) Packaging completed October2009 Arrival at Keppel Yard November 2009 Installation completed December...

10 UNIQUE RECIPROCATING COMPRESSOR SOLUTION FOR OFFSHORE APPLICATIONS Fig.10 On-board installation area of the Laby®-GI 4LP250-3A on Golar Freeze FSRU Fig. 11 Laby®-GI 4LP250-3A packaged unit in the workshop (three module concept) The compressor package was designed to be installed on the port side between the first and second spherical tank. In addition, Burckhardt Compression also delivered the glycol/water closed cooling water system for this project. Fig. 10 4.2.1 DESIGN AND MODULAR CONCEPT The three module concept was used for the installation. The modules are packaged and pre-adjusted prior...

UNIQUE RECIPROCATING COMPRESSOR SOLUTION FOR OFFSHORE APPLICATIONS 11 Fig.12 Real installation of the Laby®-GI 4LP250-3A Golar Freeze CHAPTER 5 CONCLUSION The unique design of the Laby®-GI, extensive studies and detailed analysis led to a successful first installation of the 4LP250 on-board the Golar Freeze. Even though Burckhardt Compression is experienced in this kind of project execution, it was a remarkable job to conduct. With our in-house capabilities in combination with up-to-date engineering and design tools, it was possible to analyze and define the Laby®-GI 4LP250-3A in a very short...