Criterios de izajes pesados (superestructuras)

GUIDELINES FOR MARINE OPERATIONS

MARINE LIFTING

February 1998

London Offshore Consultants GUIDELINES FOR MARINE OPERATIONS LIFTING

TABLE OF CONTENTS 1. INTRODUCTION................................................................................................................... 4 1.1 1.2 1.3 1.4 2. Scope of Guidelines Definitions Reference Documents Certificates of ApprovalPLANNING OF MARINE LIFTS ........................................................................................ 7 2.1 2.2 2.3 2.4 2.5 2.6 General Site Survey Lifting Manual Documentation Design Calculations Operational Aspects

3.

LOADS AND ANALYSIS...................................................................................................... 9 3.1 3.2 3.3 3.4 3.5 3.6 3.7 3.8 3.9 3.10General Module Design Weight Rigging Weight Centre of Gravity and Tilt of Module - Single Crane Static Hook Load - Single Crane Lift Static Hook Load - Dual Crane Lift Dynamic Lift Load Derivation of Lifting Point Loads - Single Crane Lifts Derivation of Lifting Point Loads - Dual Crane Lifts Lifting Through Water

4.

STRUCTURES...................................................................................................................... 16 4.1 4.2 4.3 4.4 4.5 4.6 4.7 4.8 4.9 4.10 General Consequence Factors Method of Analysis of Module Strength of Module Padeye Design Padears and Trunnions Cast Lifting Points Fabrication and Installation of Lifting Points Seafastening Bumpers and Guides

London Offshore Consultants GUIDELINES FOR MARINE OPERATIONS LIFTING

5.REQUIREMENTS FOR LIFTING EQUIPMENT ......................................................... 21 5.1 5.2 5.3 5.4 5.5 General Sling Force Distribution Shackles Spreader Beams Hydraulic Lifting Devices

6.

CRANE AND CRANE VESSELS ...................................................................................... 24 6.1 6.2 6.3 6.4 6.5 General Allowable Load Crane Radius Curve Minimum Clearances CraneVessel Stability

APPENDICES Appendix A1: Summary of Stages in Design/Analysis of Single Crane Lift Appendix A2: Summary of Stages in Design/Analysis of Dual Crane Lift

London Offshore Consultants GUIDELINES FOR MARINE OPERATIONS LIFTING

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1.
1.1

INTRODUCTION
SCOPE OF GUIDELINES These guidelines are a basis for the planning, design and operational aspects of marinelifting. Guidelines for loadout and transportation are covered in the two preceding chapters. The purpose of them is to specify appropriate standards, based on sound engineering and good marine practice in order to ensure that lifting operations maintain an acceptable level of safety at all times. These guidelines are intended to cover any lifting operations which are subject to approval by the MarineWarranty Surveyor. For example:C C C Topsides Module Lifting Subsea Structure Lifting Jacket Lifting

Other considerations may apply for other categories of lift. These guidelines are based on experience over a large number of lifting operations. However, as knowledge advances in specific areas, Marine Warranty Surveyors should recognise that lifting operations may use alternative or newmethods. The fundamental principle to be followed by the introduction of novel or alternative methods is that the overall level of safety of a lifting operation should not be reduced. The Marine Warranty Surveyor for a project will require to review the following for any lifting operation requiring approval:C C C C Design specifications Proposed lifting procedure Rigging design Crane vessel detailsThis information should be made available to the MWS in sufficient time to enable completion of these reviews well before the planned operations.

1.2

DEFINITIONS Company: Warranted Company or representatives acting on their behalf.

GuidLFT. February 1996

London Offshore Consultants GUIDELINES FOR MARINE OPERATIONS LIFTING

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MWS: Marine Warranty Surveyor and/or Marine...