1、 GUIDE FOR THE CLASSIFICATION NOTATION THRUSTER-ASSISTED MOORING (TAM, TAM-R, TAM (Manual) FOR MOBILE MOORING SYSTEMS JANUARY 2013 Guide to Color Coding Used in Online Version of the Guide The following summarizes the colors corresponding to Rule Changes, Corrigenda items and editorial changes in th
2、e Guide files which are available for download. Rule Changes: NOTICE NO. 1 December 2015 (effective 1 December 2015) Corrigenda: CORRIGENDA/EDITORIALS 1 February 2014 Editorials: Editorial Changes Guide for the Classification Notation THRUSTER ASSISTED MOORING (TAM, TAM (Manual) FOR MOBILE MOORING S
3、YSTEMS GUIDE FOR THE CLASSIFICATION NOTATION THRUSTER-ASSISTED MOORING (TAM, TAM-R, TAM (Manual) FOR MOBILE MOORING SYSTEMS JANUARY 2013 (Updated December 2015 see next page) American Bureau of Shipping Incorporated by Act of Legislature of the State of New York 1862 Copyright 2013 American Bureau o
4、f Shipping ABS Plaza 16855 Northchase Drive Houston, TX 77060 USA Updates December 2015 consolidation includes: February 2014 version plus Notice No. 1 February 2014 consolidation includes: January 2013 version plus Corrigenda/Editorials Foreword Foreword (1 December 2015) Due to the increased incor
5、poration of thruster-assisted mooring (TAM) capability in the design of mooring systems for mobile offshore units, there is a desire in the offshore industry for optional classification notations for TAM systems. This Guide is developed and issued in response to that desire. The evaluation procedure
6、 and technical requirements are to be used for verifying the eligibility of a TAM system (for mobile offshore units) for the optional notations TAM (Automatic position control system), TAM-R (Automatic position control system with redundancy), and TAM (Manual) (Manual position control system). It is
7、 anticipated that after publication of the subject Guide, industry will have established criteria for TAM, thereby allowing verification of the arrangements and potentially increasing the overall level of safety. This Guide becomes effective on 15 January 2013. Users are advised to check periodicall
8、y on the ABS website www.eagle.org to verify that this version of this Guide is the most current. We welcome your feedback. Comments or suggestions can be sent electronically by email to rsdeagle.org. ABSGUIDE FOR THE CLASSIFICATION NOTATION THRUSTER-ASSISTED MOORING FOR MOBILE MOORING SYSTEMS .2013
9、 iii Table of Contents GUIDE FOR THE CLASSIFICATION NOTATION THRUSTER ASSISTED MOORING (TAM, TAM-R, TAM (Manual) FOR MOBILE MOORING SYSTEMS CONTENTS SECTION 1 Introduction 1 1 General . 1 3 Application . 1 3.1 Class Notations 1 5 Definitions . 2 7 Plans and Particulars to be Submitted 2 9 References
10、 2 SECTION 2 Technical Requirements for Notations . 3 1 General . 3 3 Analysis Conditions for Thruster-Assisted Mooring (TAM, TAM-R) System 3 5 Mooring System 4 5.1 Anchoring Systems 4 5.3 Equipment . 5 5.5 Anchor Lines 5 5.7 Anchors . 6 5.9 Quality Control . 6 5.11 Control Stations . 6 7 Thrust Cap
11、acity . 6 9 Thruster-Assisted Mooring Analysis . 7 11 System Requirements . 7 11.1 Thruster System 7 11.3 Power Generation and Distribution System . 7 11.5 Environment Sensor and Position Reference System . 7 11.7 Control and Instrumentation System 7 11.9 Communications for Units with Thrust Assist
12、Capability 8 TABLE 1A ntact and Damaged TAM Definitions 3 TABLE 1B Intact and Damaged TAM-R Definitions . 3 TABLE 2 Mooring Line Factor of Safety . 4 TABLE 3 Allowable Thrust for Manual and Automatic Thrust Assist (TA) Systems 6 TABLE 4 Instrumentation at TA Control Station . 8 iv ABSGUIDE FOR THE C
13、LASSIFICATION NOTATION THRUSTER-ASSISTED MOORING FOR MOBILE MOORING SYSTEMS .2013 SECTION 3 Survey Requirements for Notations . 9 1 Survey During Construction 9 1.1 Thrusters and Associated Equipment 9 1.3 Control and Monitoring System Equipment . 9 3 Survey After Construction . 9 ABSGUIDE FOR THE C
14、LASSIFICATION NOTATION THRUSTER-ASSISTED MOORING FOR MOBILE MOORING SYSTEMS .2013 v This Page Intentionally Left Blank Section 1: Introduction SECTION 1 Introduction 1 General Thrusters may be used to assist the mooring system by reducing the mean environmental forces, controlling the offshore units
15、 heading, damping low frequency motions, or a combination of these functions. Thruster-assisted mooring (TAM) systems can be broadly categorized into manual and automatic position control, depending on the type of thrust assist (TA) system fitted on the unit. 3 Application (1 December 2015) The prov
16、isions of this Guide apply to mobile offshore units operating with TAM systems. Sections 2 and 3 of the Guide provide the technical requirements and survey requirements for the optional notations: TAM (Automatic position control system), TAM-R (Automatic position control system with redundancy), and
17、 TAM (Manual) (Manual position control system) for mobile offshore units. At the request of the Owners, the TAM system may be verified for compliance with the provisions of Sections 2 and 3, with the appropriate class notation assigned. This Guide may be used in tandem with Appendix 3-4-A1, “Guide f
18、or Position Mooring Systems” of the ABS Rules for Building and Classing Mobile Offshore Drilling Units (MODU Rules). 3.1 Class Notations (1 December 2015) The requirements for conditions of Classification for the entire drilling units and offshore structures are contained in the ABS Rules for Condit
19、ions of Classification Offshore Units and Structures (Part 1). Additional requirements specific to thruster-assisted mooring systems are contained in this Guide. For TAM systems, which are fitted with a TA system that is capable of automatically maintaining the position and heading of the unit under
20、 specified maximum environmental conditions having an independent centralized manual position control with automatic heading control that have been built, installed and commissioned to the satisfaction of the ABS Surveyors to the full requirements of this Guide, where approved by the Committee for s
21、ervice for the specified design environmental conditions, will be classed and distinguished in the ABS Record by the notation null TAM. For TAM systems, which are fitted with a TA system that is capable of automatically maintaining the position and heading of the unit under specified maximum environ
22、mental conditions with redundancy as determined by failure mode and effects analysis (FMEA) having an independent centralized manual position control with automatic heading control that have been built, installed and commissioned to the satisfaction of the ABS Surveyors to the full requirements of t
23、his Guide, where approved by the Committee for service for the specified design environmental conditions, will be classed and distinguished in the ABS Record by the notation null TAM-R. For TAM systems, which are fitted with a TA system with centralized manual position control and automatic heading
24、control to maintain the position and heading under specified maximum environmental conditions that have been built, installed and commissioned to the satisfaction of the ABS Surveyors to the full requirements of this Guide, where approved by the Committee for service for the specified design environ
25、mental conditions, will be classed and distinguished in the ABS Record by the notation null TAM (Manual). This notation assumes continuous attention of a TA operator. The symbol “null” (Maltese-Cross) signifies that the system was built, installed and commissioned to the satisfaction of the ABS Surv
26、eyors. TAM systems that have not been built under survey to ABS, but which are submitted for Classification, will be subjected to special consideration. Where found satisfactory and thereafter approved by the Committee, it will be classed and distinguished in the Record by the notation described abo
27、ve, but the symbol “null” signifying survey during construction will be omitted. ABSGUIDE FOR THE CLASSIFICATION NOTATION THRUSTER-ASSISTED MOORING FOR MOBILE MOORING SYSTEMS .2013 1 Section 1 Introduction 5 Definitions Thrusters. Thrusters are devices capable of delivering side thrust or thrusts th
28、rough 360 to improve the vessels maneuverability, particularly in confined waters. For more details, refer to 4-3-5/1.5 of the ABS Rules for Building and Classing Steel Vessels (Steel Vessel Rules). Thrust Assist (TA) System. Thrust assist system is a hydro-dynamic system which utilizes thrusters an
29、d dynamic positioning capability to assist the mooring system in controlling or maintaining the position and heading of the vessel by centralized manual control or by automatic response to the variations of the environmental conditions within the specified limits. Specified Maximum Environmental Con
30、ditions. The specified maximum environmental conditions are the specified wind speed, current and wave height under which the unit is designed to carry out intended operations. Specified Operating Envelope. The specified operating envelope is the area within which the unit is required to stay in ord
31、er to satisfactorily perform the intended operations under the specified maximum environmental conditions. Damaged Condition. Damaged condition is defined as loss of single mooring line or loss of single thruster or single engine/generator. A failure in the TA system that results in thruster(s) inop
32、erability shall be considered equivalent to damaged condition. 7 Plans and Particulars to be Submitted The general arrangements of the thruster(s) installation, its location of installation, together with its supporting auxiliary machinery systems, fuel oil tanks, foundations, watertight boundary fi
33、ttings, etc., are to be submitted. The rated power/rpm and the rated thrust are to be indicated. For azimuthal thrusters, the mechanical and control systems for rotating the thruster assembly or for positioning the direction of thrust are to be submitted. Thruster specifications and calculations for
34、 thruster forces and power to counteract environmental forces are to be submitted. In addition, plans of each component and of the systems associated with the thruster are to be submitted. In addition, plans showing the arrangement and complete details of the anchoring system, including anchors, sha
35、ckles, anchor lines consisting of chain, wire or rope, together with details of fairleads, windlasses, winches and any other components of the anchoring system and their foundations and attachments to the unit are to be submitted. Mooring analysis describing method of load calculations and analysis
36、of dynamic system to determine the mooring line design loads is to be submitted. Specifications and calculations for all components of the anchoring system are to be submitted. The type and design of anchors are to be submitted for review, together with documentation estimating their holding power i
37、n various types of soil. Model test report when the design loads are based on model tests is to be submitted, if applicable. 9 References Some of the applicable requirements of the following Rules, Guides, Codes and Standards are referenced in this Guide are listed below: ABS Rules for Building and
38、Classing Mobile Offshore Drilling Units ABS Rules for Building and Classing Steel Vessels ABS Guide for the Certification of Offshore Mooring Chain ABS Guidance Notes on the Application of Fiber Ropes for Offshore Mooring API RP 2SK Design and Analysis of Stationkeeping Systems for Floating Structur
39、es API Spec 9A Specification for Wire Rope 2 ABSGUIDE FOR THE CLASSIFICATION NOTATION THRUSTER-ASSISTED MOORING FOR MOBILE MOORING SYSTEMS .2013 Section 2: Technical Requirements for Notations SECTION 2 Technical Requirements for Notations 1 General (1 December 2015) In evaluating the capability of
40、the TAM system for mobile offshore units with the intent of assigning the optional notation TAM, TAM-R, or TAM (Manual), the provisions in this Section are to be complied with as applicable. 3 Analysis Conditions for Thruster-Assisted Mooring (TAM, TAM-R) System (1 December 2015) The TAM or TAM-R sy
41、stem shall be designed for the intact and damaged conditions as defined in Section 2, Tables 1A and 1B. TABLE 1A Intact and Damaged TAM Definitions TAM Definition and Mooring Line Factor of Safety Mooring System Condition Thrust Assist (TA) System Condition Intact Intact Intact Damaged Intact Damage
42、d Damaged Damaged Intact TABLE 1B Intact and Damaged TAM-R Definitions (1 December 2015) TAM-R Definition and Mooring Line Factor of Safety Mooring System Condition Thrust Assist (TA) System Condition Intact Intact Intact Damaged Intact Damaged with redundancy as determined by failure mode and effec
43、ts analysis (FMEA). Damaged Damaged Intact Damaged condition is defined as loss of a single mooring line or loss of a single thruster or single engine/ generator. A failure in the TA system that results in thruster(s) inoperability shall be considered equivalent to damaged condition. The mooring lin
44、e factor of safety is specified in Section 2, Table 2. For additional design considerations of the mooring system, refer to Appendix 3-4-A1 of the MODU Rules. ABSGUIDE FOR THE CLASSIFICATION NOTATION THRUSTER-ASSISTED MOORING FOR MOBILE MOORING SYSTEMS .2013 3 Section 2 Technical Requirements for No
45、tations TABLE 2 Mooring Line Factor of Safety Analysis Condition Mooring Line Factor of Safety (FOS) Quasi-Static Analysis Dynamic Analysis Operating Intact 2.70 2.25 Damaged 1.80 1.57 Transient 1.40 1.22 Severe Storm Intact 2.00 1.67 Damaged 1.43 1.25 Transient 1.18 1.05 5 Mooring System 5.1 Anchor
46、ing Systems 5.1.1 An analysis of the anchoring arrangements expected to be utilized in the units operation is to be submitted. Among the items to be addressed include: i) Design environmental conditions of waves, winds, currents, tides and ranges of water depth ii) Description of analysis methodolog
47、y 5.1.2 The anchoring system should be designed so that a failure of any single component will not cause progressive failure of the remaining anchoring arrangements. 5.1.3 Anchoring system components should be designed utilizing adequate factors of safety (FOS) (see Section 2, Table 2) and a design
48、methodology suitable to identify the most severe loading condition for each component. In particular, sufficient numbers of heading angles together with the most severe combination of wind, current and wave are to be considered, usually from the same direction, to determine the maximum tension in ea
49、ch mooring line. The effects of the thrust assist (TA) system (see Subsection 2/9) shall be considered. The owner is to specify the environmental conditions for which the TAM system is to be designed for. 5.1.4 When a quasi-static analysis method is applied, the tension in each anchor line is to be calculated at the maximum excursion for each design condition defined in Section 2, Table 2, combining the following steady state and dynamic responses of the unit: i) Steady mean offset due to the defined wind, current and steady wave forces. ii) Maximum surge/sw
