DAF - Spreader Bar

[hungrydinosaur]

Hi All,

As per DNV Rules for Lifting Appliance, what is the DAF we need to use for a spreader bar of SWL 400 Tonnes? Also, any idea on what GL mentions for this? Thanks in advance.

HD

 

[msquared48]

FYINO.

Mike McCann
MMC Engineering

 

[BAretired]

ME2.

BA

 

[ztengguy]

Whats DNV, DAF and GL?

 

[dhengr]

HD:
You left the “T” off the end of “DAF.” If you want any meaningful help, we shouldn’t have to waste our time looking up and guessing at the meaning of acronyms, however smart their usage may make you think you look. And, some of us won’t have copies of the DNV standards either, but might still be helpful if you define your problem better. Show a sketch of the spreader beam and its fittings, and attachments (copies) of the code sections and formulas you are having trouble with, so we can see what you’re dealing with. The various codes and stds. may vary a little, but the basic engineering mechanics don’t change, and some of us have likely seen essentially the same problem under another code.

 

[boo1]

DNV = Det Norske Veritas, Norwegian maritime classification society
GL = Germanischer Lloyd, German maritime classification society
DAF = Dynamic Amplification Factor, which is a function of load and sea condition. Typically table DAFs are used for
different load groups and inshore and offshore lift in air in minor sea states, typically Hs <2-2.5m

DNV and GL have joined societies;

http://www.dnvgl.com/

 

[boo1]

GL says, DAF varies depending on structure lift weight, crane motions and whether lift is in air, submerged or partly submerged, water depth and current regime. Simplified in-air DAF factors are maximum factors, and are often used in lieu of a DAF analysis where a DAF analysis is required (limiting sea state derivation, actual motions.)"

See GL doc attached