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Sungguh senang mengamati jalannya diskusi mengenai FPSO di Milis Migas Indonesia beberapa hari terakhir ini. Diskusi sudah berkembang menjadi masukan untuk BKI. Sebagai referensi, saya sudah upload softcopy presentasi Bpk. Harsono – IMAREST mengenai “International Safety Management Code” yang dibawakan pada Seminar Offshore Floating Structure Technology di ITB, 26 Juni 2009.

Pembahasan – Budhi Swastioko Suryanto

Sungguh senang mengamati jalannya diskusi mengenai FPSO di Milis Migas Indonesia beberapa hari terakhir ini. Diskusi sudah berkembang menjadi masukan untuk BKI. Sebagai referensi, saya sudah upload softcopy presentasi Bpk. Harsono – IMAREST mengenai “International Safety Management Code” yang dibawakan pada Seminar Offshore Floating Structure Technology di ITB, 26 Juni 2009. Silahkan mendownloadnya dari URL :

http://www.migas-indonesia.net/index.php?option=com_docman&task=cat_view&gid=311&Itemid=42.

Tanggapan 1 – Henry Margatama

Wah, akhirnya dipublish juga. Terima kasih byk.

Tanggapan 2 – Admin Migas

Ternyata setelah saya teliti folder Seminar Offshore Floating Structure Technology, Bpk. Harsono juga menyertakan lampiran-lampiran dokumen dari ISM Code. Dokumen ‘International Safety Management Code – Article’ dan terjemahan ISM Code Edisi 2002 ‘Kode Internasional Untuk Manajemen Pengoperasian Kapal-Kapal Dengan Aman Dan Untuk Pencegahan Pencemaran’ sangat baik dibaca untuk mengetahui isi dari slide presentasi beliau, apalagi bagi yang tidak hadir sewaktu seminar diadakan di ITB Bandung 26 Juni 2009. Silahkan download dari URL :

http://www.migas-indonesia.net/index.php?option=com_docman&task=cat_view&gid=311&Itemid=42.

Tanggapan 3 – Didik Pramono

Dari presentasi yang disampaikan Pak Justinus, floating platform (termasuk MOPU) masuk dalam kategori ship, sehingga harus memenuhi ketentuan UU No.17 tahun 2008 antara lain masuk Class dan mempunyai bendera.

Saya pernah menjumpai di salah satu operasi KKKS, jack-up platform (yang merupakan salah satu kategori MOPU) digunakan sebagai production platform, fix dan tidak pernah lagi berpindah-pindah seperti layaknya jacket platform. Bahkan deck level-nya pun sudah di set fix dan system hydroulic jack-nya sudah tidak difungsikan lagi.

Sesuai dengan ketentuan regulasi diatas, apakah jack-up ini masih ada kewajiban untuk memenuhi ketentuan regulasi diatas? Mohon pencerahan.

Tanggapan 4 – El Mundo

P. Budhi,

Sejak kapan addressnya di ganti?

Karena kita semua menginginkan BKI itu besar bukan saja di kandang sendiri tetapi juga di luar, terlampir persyaratan IACS utk seourang exlusive surveyor. mudah2an dapat menjadi bench mark bagi kawan2 yg berprofesi Class Surveyor.

Tanggapan 5 – El Mundo

Maksud Didik, jackup yg di pake ConocoPhillips utk Hang Tua field di Natuna?
Jika ya, Jackup tsb sudah berubah fungsi dan dikategorikan sbg fixed platform, sehingga tidak perlu di kelaskan atau mempunyai port of registry.

Tanggapan 6 – Didik Pramono

Hang Tuah MOgPU platform di fabrikasi di Ulsan, Korsel. Pada saat dia di tow (dry and wet) ke Natuna site, apakah tidak perlu diklaskan dan mempunyai bendera? Dengan pertimbangan lain sebagai kategori MOPU, dia mempunyai ability dapat di relocate to other area at any time during its design life. Mohon pencerahan.

Tanggapan 7 – budi setyo

Yth Rekans MIGAS,

Hang Tuah Jack Up ini agak istimewa, karena memang dia didesign dengan sistem jacking system yang agak ‘unik’ kalau boleh dikatakan spesial.
Biasanya Jack-up untuk menaik turunkan lambung memakai jacking sytem yang terdiri, gigi gigi (rack) yang menempel pada kaki untuk tubular leg dan pada chord untuk truss leg dan gigi gigi pinion yang terletak diatas geladak lambung. Pinion ini seperti gir sepeda, berputar dengan tenaga motor atau hidrolik. Karena pinion menghubungkan rack pada kaki, maka begitu pinion berputar, maka kaki ikut juga bergerak (kebawah atau ke atas) bergantung desain arah putaran.

Hang Tuah didesain oleh ACE (Arup teknologi , kalau ndak salah, mohon koreksi kalau salah), sehingga nama awal project ini adalah ACE MOG POU, kemudian setelah jadi, diganti dengan Hang Tuah MoG POU. Hang Tuah di desain dengan suatu sistem jack up pakai wire rope, jadi tanpa gigi gigi rack pada kaki. Pada kaki bagian atas, ada puley yang dihubungkan dengan motor penggerak dibagian tengah antara geladak atas dengan puley. Ujung yang lain dihubungkan dengan bagian hul base bawah (ada 2 hull, satu yang nantinya ditenggelamkan sebagai mudmat). Sehingga kalau motor penggerak bekerja, akan menggulung atau mengendurkan tali, sehingga hull bagian bawah akan juga ikut bergerak, naik atau turun. Motor penggerak dirancang bisa dipasang dan bisa di lepas. Sistem jacking ini, diklaim oleh desainer sebagai yang lebih ekonomis dibanding dengan dengan sistem yang umum dipakai, pakai rack dan pinion.
Jadi menurut, pendapat saya yang awam ini, bukan kebetulan, bahwa jacking sistem pada Hang Tuah Platform dilepas dan struktur ini jadi sepenuhnya struktur fixed. Karena memang saat desain awal, jacking sistem bisa dilepas dan dipasang.

Kebetulan saya sedikit ikut ikutan project ini, melakukan studi dan analisa dengan pengujian sub scale model, kalau ndak salah th 1998, jadi sedikit tahu.

Untuk hubungan antara Clas dan flag untuk Jack Up, berikut saya cited salah satu paragraph dari suatu artikel ilmiah berjudul : ‘ Jack Up Unit, a Technical primer for the Offfshore primer for the offshore industrial profesional ‘ dibagian bawah e-mail ini.

Mohon dikoreksi dan ditambahi jika ada salah atau kurangnya.

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5. CLASS APPROVAL VS. SITE SPECIFIC ASSESSMENT

There are many parties involved in the safety regime for jack ups. These include Shelf States (national legislation), Flag States (national maritime legislation), Class Societies (class rules), and International Bodies (international codes, e.g, MODU code, etc.).

Jack ups may not require a flag but are free to move in international waters when carrying flag. In such case a jack up has to comply with safety regulations of the Maritime Authority in the country whose flag the unit is flying (the Flag State).

Jack up drilling units are normally registered with a Flag State Governmental Administration. The role of the Flag Administration, is to implement statutory requirements of the government for registering the unit. Normally, these statutory requirements are derived from internationally agreed regulations developed by the International Maritime Organization (IMO). Today, Flag Administrations largely delegate the tasks of verification of compliance with IMO Conventions to classification societies. Classification societies also issue Loadline, Tonnage and Marpol certificates on behalf of Flag Administrations.

Besides classification and statutory requirements, some governments require drilling units, regardless of flag, operating in their territorial waters to comply with their own safety and pollution requirements. A typical example is in the UK. The UK Health and Safety Executive’s Offshore Division enforces health and safety laws on offshore installations, including jack up drilling units.

Classification societies are independent, third party organizations that serve as a verification system for a number of parties who have special interest in the safety and quality of jack ups. These may include regulatory authorities, insurance underwriters, owners, building yards and sub-contractors, finance institutions, and charterers.

5.1 CLASSIFICATION SOCIETIES

Classification is a comprehensive verification service providing assurance that a set of requirements laid down in rules and standards established by the classification society are met during design and construction and maintained during operation of the jack up. The rules and standards ensure safety against hazards to the unit, personnel and the environment. Each classification society, such as the American Bureau of Shipping (ABS), Det Norske Veritas (DNV), Lloyds Register (LR), etc., has its own rules for classification of jack ups. However, many aspects of classification rules of different classification societies are harmonized through the International Association of Classification Societies (IACS). Like ships and other marine structures, jack up drilling units are designed and constructed to satisfy the rules of classification societies. While classification certificates issued by a classification society attest to compliance with such

Rules, they also indicate that the unit meets a minimum industry standard for structural and mechanical fitness. To maintain the unit in class, classification societies require periodical surveys to check that the unit is adequately maintained.

The class structural scope includes structural strength, materials, welding, fabrication and corrosion protection for jack up hull, superstructures, legs, spudcans, etc. The rig’s ultimate strength in different operation modes, like storm survival, elevated operations, transit, preloading and jacking, etc. are considered. Possible accidental conditions and fatigue are also examined. Design conditions used as bases for the strength approval, such as hull weights, water depths, environmental conditions, etc., are presented in the rig’s operation manual. Assumed foundation fixities may be considered and in such cases included in the operation manual. However, foundation capacity and safety is not part of class structural approval for a jack up rig.

It is the owner’s responsibility to operate the jack up within the conditions used as basis for class approval, and to confirm that the unit can safely operate at a particular site.

Classification rules (e.g. ABS Rules for Building and Classing Mobile Offshore Drilling Units) typically address the following areas:

o Materials of construction and fabrication

o Structural integrity

o Afloat stability

o Safety issue such as structural fire protection and means of escape

o Machinery and systems

o Periodical survey

Since jack up units are mobile in nature and can be expected to operate in any part of the world, the rules for structures are not associated with the environmental, geotechnical and operational conditions of any specific area. The owner and designer define the environmental and operational conditions to which the unit has been designed; these are the design criteria and theoretical operating envelope of the unit. Designers and owners must assess the desired operating modes and site conditions to ensure they are within the approved envelope.

Classification rules require global analyses of the primary structure of the unit in the jacked up and afloat modes of operation. In the transit (afloat) condition leg structures are assumed subjected to defined roll characteristics and gravity bending moment, with correspondingly more demanding criteria in severe storm condition. In addition to the global structural analysis, fatigue analyses are required for classification of all new construction jack ups. Machinery and systems classification requirements are derived mainly from rules for ships, except for specific equipment, such as jacking gears, and safety requirements related to hazards of drilling operations, such as definition of hazardous areas and the installation of electrical equipment in such areas, high pressure piping systems related to drilling, fire safety systems, emergency shutdown systems, and others.

Classification rules impose stability criteria for jack up units in all afloat conditions, including temporary conditions, such as lowering leg structures. Two sets of criteria are specified: intact stability and damage stability criteria. While classification of a jack up unit signifies its compliance with a set of minimum standards (Classification Rules), it does not imply that the jack up is adequate to operate in any specific area. In fact, in each case, the owner/operator of the unit should assess the adequacy of the jack up taking into consideration the water depth, environmental, geotechnical, seismic and climatic conditions of the area of operation. For this purpose, industry has developed a standard: SNAME T&R Bulletin 5-A

5A Guidelines for Site Specific Assessment of Mobile Drilling Units, which can be used as a guide for performing such assessments

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